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CONTENTS HOW TO USE MANUAL 1-2 BOATING SAFETY 1-4 SAFETY IN SERVICE 1-11 TROUBLESHOOTING 1-11 TOOLS AND EQUIPMENT 1-15 TOOLS 1-17 FASTENERS, MEASUREMENTS AND CONVERSIONS 1-24 SPECIFICATIONS 1-25 ENGINE AND DRIVE MAINTENANCE FLUIDS AND LUBRICANTS LUBRICATION POINTS BOAT MAINTENANCE WINTER STORAGE ORDERS SPRING COMMISSIONING SPEClFlCATlONS ENGINE MECHANICAL SPECIFICATIONS ENGINE MECHANICAL EXPLODED VIEWS SPECIFICATIONS ENGINE MECHANICAL EXPLODED VIEWS SPECIFICATIONS ENGINE MECHANICAL EXPLODED VIEWS SPECIFICATIONS ENGINE 7-2 FUEL AND COMBUSTION CARBURETEDFUELSYSTEM ROCHESTER 2 BBL ROCHESTER 4 BBL HOLLEY 2300 2 BBL HOLLEY 41501416014175 4 BBL DIAGRAMS SPECIFICATIONS CONTENTS FUEL AND COMBUSTION FORD ELECTRONIC MULTI-POINT FUEL INJECTION (MFI) SYSTEM DIAGNOSIS GM MULTI-POINT FUEL INJECTION SPEClFlCATlONS SCHEMATICS DIAGNOSTIC TROUBLE CODE (DTC) CHARTS FUEL FLOW DIAGRAMS COMPONENT LOCATIONS UNDERSTANDING AND TROUBLESHOOTING ELECTRICAL SYSTEMS BATTERY CHARGING SYSTEM STARTER CIRCUIT IGNITION SYSTEM BREAKER POINT IGNITION SYSTEM ELECTRONIC SPARK TIMING (EST) SYSTEM DISTRIBUTOR IGNITION SYSTEM INTEGRAL BREAKERLESS INDUCTIVE DISTRIBUTOR (BID) SYSTEM ENGINE MANAGEMENT (EMM) SYSTEM FORD THICK INTEGRATED IGNITION SYSTEM (TFI-IV) INSTRUMENTS AND GAUGES SENDING UNITS AND SWITCHES DIAGRAMS SPECIFICATIONS COOLING SYSTEM MAINTENANCE AND TESTING FLOW DIAGRAMS STERN DRIVE COBRA, KlNG COBRA, SP, SX, SX COBRA, DP AND DP MODELS UPPER GEAR HOUSING LOWER GEAR HOUSING UNIT) TRANSOM ASSEMBLY SPECIFICATIONS SELECT (POWER) AND COBRA AND KlNG COBRA POWER AND 1989-98 COBRA, KlNG COBRA, AND DP SCHEMATICS MANUAL POWER MASTER INDEX BASIC OPERATING PRINCIPLES 1-12 2-STROKE MOTORS 1-12 4-STROKE ENGINES 1-14 COMBUSTION 1-14 BOATING SAFETY .................... 1-4 COURTESY MARINE EXAMINATIONS 1-11 EQUIPMENT NOT REQUIRED BUT RECOMMENDED 1-10 REGULATIONS FOR YOUR BOAT REQUIRED SAFETY EQUIPMENT ....... 1-5 CHEMICALS 1-15 CLEANERS 1-16 LUBRICANTS PENETRANTS ......... 1-15 SEALANTS 1-16 COURTESY MARINE EXAMINATIONS 1-11 ELECTRONIC TOOLS 1-21 BATTERY CHARGERS 1-21 BATTERY TESTERS 1-21 GAUGES 1-22 (DVOMS) 1-21 EQUIPMENT NOT REQUIRED BUT RECOMMENDED 1-10 ANCHORS 1-10 BAILING DEVICES 1-10 FIRST KIT 1-10 SECOND MEANS OF PROPULSION 1-10 TOOLS AND SPARE PARTS 1-1 0 VHF-FM RADIO 1-10 FASTENERS. MEASUREMENTS AND CONVERSIONS 1-24 BOLTS. NUTS AND OTHER THREADED RETAINERS 1-24 STANDARD AND METRIC MEASUREMENTS 1-24 TORQUE 1-24 HAND TOOLS 1-17 BREAKER BARS 1-18 HAMMERS 1-20 PLIERS 1-20 SCREWDRIVERS 1-20 SOCKET SETS 1-17 TORQUE WRENCHES 1-18 WRENCHES 1-19 HOW TO USE MANUAL AVOIDING THE MOST COMMON MISTAKES 1-3 AVOIDING TROUBLE 1-2 CAN YOU DO IT? 1-2 AND LOCATIONS 1-2 MAINTENANCE OR REPAIR? 1-2 PROFESSIONAL HELP 1-3 PURCHASING PARTS ......... WHERE TO BEGIN MEASURING TOOLS ........... INDICATORS ............ DEPTH GAUGES MICROMETERS CALIPERS ... TELESCOPING GAUGES ....... OTHER COMMON TOOLS ....... REGULATIONS FOR YOUR BOAT . CAPACITY INFORMATION ...... CERTIFICATE OF COMPLIANCE . DOCUMENTING OF VESSELS ... HULL IDENTIFICATION NUMBER . LENGTH OF BOATS ........... NUMBERING OF VESSELS ..... REGISTRATION OF BOATS ..... SALES AND TRANSFERS ...... VENTILATION VENTILATION SYSTEMS ....... REQUIRED SAFETY EQUIPMENT . TYPES OF FIRES ............. EXTINGUISHERS ........ PERSONAL FLOTATION DEVICES SOUND PRODUCING DEVICES . . VISUAL DISTRESS SIGNALS .... WARNING SYSTEM ........... SAFETY IN SERVICE ........... DO'S DON'TS SAFETY TOOLS EYE AND EAR PROTECTION .... WORK CLOTHES WORK GLOVES .............. SPECIAL TOOLS ............... SPECIFICATIONS .............. CONVERSION FACTORS ....... METRIC BOLTS .TYPICAL TORQUE VALUES ............ U.S. STANDARD BOLTS VALUES TROUBLESHOOTING BASIC OPERATING PRINCIPLES . TOOLS ELECTRONIC TOOLS .......... HAND TOOLS MEASURING TOOLS .......... OTHER COMMON TOOLS ...... SPECIAL TOOLS ............. TOOLS AND EQUIPMENT ....... CHEMICALS SAFETY TOOLS 1-2 GENERAL INFORMATION. SAFETY AND TOOLS This manual is designed to be a handy reference guide to maintaining and repairing your OMC engine and drive system. We strongly believe that regardless of how many or how few year's experience you may have, there is something new waiting here for you. This manual covers the topics that a factory service manual (designed for factory trained mechanics) and a manufacturer owner's manual (designed more by lawyers than boat owners these days) covers. It will take you through the basics of maintaining and repairing your system, step-by-step, to help you understand what the factory trained mechanics already know by heart. By using the information in this manual, any boat owner should be able to make better informed decisions about what they need to do to maintain and enjoy their OMC. Even if you never plan on touching a wrench (and if so, we hope that we can change your mind), this manual will still help you understand what a mechanic needs to do in order to maintain your engine. If you are not the type who is prone to taking a wrench to something, NEVER FEAR. The procedures provided here cover topics at a level virtually anyone will be able to handle. And just the fact that you purchased this manual shows your interest in better understanding your OMC. You may find that maintaining your system yourself is preferable in most cases. From a monetary standpoint, it could also be beneficial. The money spent on hauling your boat to a marina and paying a tech to service the engine could buy you fuel for a whole weekend's boating. If you are unsure of your own mechanical abilities, at the very least you should fully understand what a marine mechanic does to your boat. You may decide that anything other than maintenance and adjustments should be performed by a mechanic (and that's your call), but know that every time you board your boat, you are placing faith in the mechanic's work and trusting him or her with your well-being, and maybe your life. It should also be noted that in most areas a factory-trained mechanic will command a hefty hourly rate for off site service. This hourly rate is often charged from the time they leave their shop to the time that they return home. The cost savings in doing the job yourself might be readily apparent at this point. Of course, if even a seasoned or a Professional you'll find'the procedures, specifications, special tips as well as the schematics and illustrations when tacklina a new iob on an engine. To help you decide if a task is within your skill level, procedures will often be rated using a wrench svmbol in the text. When the number of wrench& designates how difficult we feel the procedure to be on a 1-4 scale. For more details on the wrench icon ratina svstem. please refer to the information under Skill Levels at the of this manual. Before spending any money on parts, and before removing any nuts or bolts, read through the entire procedure or topic. This will give you the overall view of what tools and supplies will be required to perform the procedure or what questions need to be answered before purchasing parts So read ahead and plan ahead. Each operation should be approached logically and all procedures thoroughly understood before attempting any work. Some procedures in this manual may require you to "label and disconnect . . . a group of lines, hoses or wires. Don't be lulled into thinking you can remember where everything goes -you won't. If you reconnect or install a part incorrectly, the engine may operate poorly, if at all. If you hook up electrical wiring incorrectly, you may instantly learn a very expensive lesson. A piece of masking tape, for example, placed on a hose and another on its fitting will allow you to assign your own label such as the letter "A, or a short name. As long as you remember your own code, you can reconnect the lines by matching letters or names. Do remember that tape will dissolve when saturated in some fluids (especially cleaning solvents). If a component is to be washed or cleaned, use another method of identification. A permanent felt-tipped marker can be very handy for marking metal parts; but remember that some solvents will remove permanent marker. A scribe can be used to carefully etch a small mark in some metal parts, but be sure NOT to do that on a gasket-making surface. SAFETY is the most important thing to remember when performing maintenance or repairs. Be sure to read the information on safety in this manual. Proper maintenance is the key to long and trouble-free engine life, and the work can yield its own rewards. A properly maintained engine performs better than one that is nealected. As a conscientious boat owner, set aside a Saturday morning, at once a month, to perform a of items that could cause oroblems. vour own loa to down which services you how the cost bate, and the amount of hours on the engine at the time. Keep all receipts for parts purchased, so that they may be referred to in case of related problems or to determine operating expenses. As a do-it-yourselfer, these receipts are the only proof you have that the required maintenance was performed. In the event of a warranty problem (on new engines), these receipts can be invaluable. It's necessary to mention the difference between maintenance and repair. Maintenance includes routine insoections, adiustments, and reolacement of parts that show signs of normal wear. for wear or deterioration. Repair implies that something has broken or is not working. A need for repair is often caused by lack of maintenance. For example: draining and refilling the oil is maintenance recommended by all manufacturers at specific intervals. Failure to do this can allow internal corrosion or damage and impair the operation of the engine, reauirina expensive repairs. While no maintenance can items from breaking or wearing out, a general rule stated: MAINTENANCE IS CHEAPER THAN REPAIR. See Figure 1 Two basic rules should be mentioned here. First, whenever the Port side of the engine (or boat) is referred to, it is meant to specify the left side of the engine when you are sitting at the helm. Conversely, the Starboard means your right side. The Bow is the front of the boat and the Stern or Aft is the rear. PORT (LEFT SIDE) --FORWARD (FRONT) STARBOARD (RIGHT SIDE) STERN --AFT Fig. 1 Common terminology used for reference designation on boats of all size. These terms are used though out the manual GENERAL INFORMATION, SAFETY AND TOOLS 1-3 Most screws and bolts are removed by turning counterclockwise, and tightened by turning clockwise. An easy way to remember this is: tighty; lefty-loosey. Corny, but effective. And if you are really dense (and we have all been so at one time or another), buy a ratchet that is marked ON and OFF (like ratchets), or mark your own. This can be especially helpful when you are bent over backwards, upside down or otherwise turned around when working on a boat-mounted component. Occasionally, there are some things when working on an engine or drive system that are beyond the capabilities or tools of the average Yourselfer This shouldn't include most of the topics of this manual, but you will have to be the judge. Some engines require special tools or a selection of special parts, even for some basic maintenance tasks. Talk to other boaters who use the same model of engine and speak with a trusted marina to find if there is a particular system or component on your engine that is difficult to maintain. You will have to decide for yourself where basic maintenance ends and where professional service should begin. Take your time and do your research first (starting with the information in this manual) and then make your own decision. If you really don't feel comfortable with attempting a procedure, DON'T DO IT. If you've gotten into something that may be over your head, don't panic. Tuck your tail between your legs and call a marine mechanic. Marinas and independent shops will be able to finish a job for you. Your ego may be damaged, but your boat will be properly restored to its full running order. So, as long as you approach jobs slowly and carefully, you really have nothing to lose and everything to gain by doing it yourself. On the other hand, even the most complicated repair is within the ability of a person who takes their time and follows the steps of a procedure. A rock climber doesn't run up the side of a cliff, takes it one step at a time and in the end, what looked difficult or impossible was conquerable. Worry about one step at a time. See Figures 2 and 3 When purchasing parts there are two things to consider. The first is quality and the second is to be sure to get the correct part for your engine. To get quality parts, always deal directly with a reputable retailer. To get the proper parts always refer to the information tag on your engine prior to calling the parts counter. An incorrect part can adversely affect your engine performance and fuel economy, and will cost you more money and aggravation in the end. Just remember, a tow back to shore will cost plenty. That charge is per hour from the time the towboat leaves their home port, to the time they return to their home port. Get the picture...$$$? Fig. 2 By far the most important asset in purchasing parts is a knowledgeable and enthusiastic parts person I Fig. 3 Parts catalogs, giving application and part number information, are provided by manufacturers for most replacement parts So whom should you call for parts? Well, there are many sources for the parts you will need. Where you shop for parts will be determined by what kind of parts you need, how much you want to pay, and the types of stores in your neighborhood. Your marina can supply you with many of the common parts you require. Using a marina as your parts supplier may be handy because of location (just walk right down the dock) or because the marina specializes in your particular brand of engine. In addition, it is always a good idea to get to know the marina staff (especially the marine mechanic). The marine parts jobber, who is usually listed in the yellow pages or whose name can be obtained from the marina, is another excellent source for parts. In addition to supplying local marinas, they also do a sizeable business in over-the-counter parts sales for the do-it-yourselfer. Almost every boating community has one or more convenient marine chain stores. These stores often offer the best retail and the convenience of one-stop shopping for all your needs'. Since they cater to the do-it-yourselfer, these stores are almost always open weeknights, Saturdays, and Sundays, when the jobbers are usually closed. The lowest prices for parts are most often found in discount stores or the auto department of mass merchandisers. Parts sold here are name and private brand parts bought in huge quantities, so they can offer a competitive price. Private brand parts are made by major manufacturers and sold to large chains under a store label. And, of course, more and more large automotive parts retailers are stocking basic marine supplies. There are 3 common mistakes in mechanical work: Following the incorrect order of assembly, disassembly or adjustment. When taking something apart or putting it together, performing steps in the wrong order usually just costs you extra time; however, it CAN break something. Read the entire procedure before beginning disassembly. Perform everything in the order in which the instructions say you should, even if you can't immediately see a reason for it. When you're taking apart something that is very intricate, you might want to draw a picture of how it looks when assembled at one point in order to make sure you get everything back in its proper position. When making adjustments, perform them in the proper order; often, one adjustment affects another, and you cannot expect satisfactory results unless each adjustment is made only when it cannot be changed by subsequent adjustments. Digital cameras are handy. you've got access to one, take pictures of intricate assemblies during the disassembly process and refer to them during assembly for tips on part orientation. 1-4 GENERAL INFORMATION, SAFETY AND TOOLS 2. Overtorquing (or undertorquing). While it is more common for overtorquing to cause damage, undertorquing may allow a fastener to vibrate loose causing serious damage. Especially when dealing with plastic and aluminum parts, pay attention to torque specifications and utilize a torque wrench in assembly. If a torque figure is not available, remember that if you are using the right tool to perform the job, you will probably not have to strain yourself to get a fastener tight enough. The pitch of most threads is so slight that the tension you put on the wrench will be multiplied many times in actual force on what you are tightening. 3. Cross-threading. This occurs when a part such as a bolt is screwed into a nut or casting at the wrong angle and forced. Cross-threading is more likely to occur if access is difficult. It helps to clean and lubricate fasteners, then to start threading with the part to be installed positioned straight inward. Always start a fastener, with your fingers. If you encounter resistance, unscrew the part and start over again at a different angle until it can be inserted and turned several times without much effort. Keep in mind that some parts may have tapered threads, so that gentle turning will automatically bring the part you're threading to the proper angle, but only if you don't force it or resist a change in angle. Don't put a wrench on the part until it has been tightened a couple of turns by hand. If you suddenly encounter resistance, and the part has not seated fully, don't force it. Pull it back out to make sure it's clean and threading properly. In 1971 Congress ordered the Coast Guard to improve recreational boating safety. In response, the Coast Guard drew up a set of regulations. Aside from these federal regulations, there are state and local laws you must follow. These sometimes exceed the Coast Guard requirements. This section discusses only the federal laws. State and local laws are available from your local Coast Guard. As with other laws, "Ignorance of the boating laws is no excuse." The rules fall into two groups: regulations for your boat and required safety equipment on your boat. Most boats on waters within Federal jurisdiction must be registered or documented. These waters are those that provide a means of transportation between two or more states or to the sea. They also include the territorial waters of the United States. DOCUMENTING OF VESSELS A vessel of five or more net tons may be documented as a yacht. In this process, papers are issued by the Coast Guard as they are for large ships. Documentation is a form of national registration. The boat must be used solely for pleasure. Its owner must be a citizen of the a partnership of citizens, or a corporation controlled by citizens. The captain and other officers must also be citizens. The crew need not be. you document your yacht, you have the legal authority to fly the yacht ensign. You also may record bills of sale, mortgages, and other papers of title with federal authorities. Doing so gives legal notice that such instruments exist. Documentation also permits preferred status for mortgages. This gives you additional security, and it aids in financing and transfer of title. You must carry the original documentation papers aboard your vessel. Copies will not suffice. REGISTRATION OF BOATS If your boat is not documented, registration in the state of its principal use is probably required. If you use it mainly on an ocean, a gulf, or other similar water, register it in the state where you moor it. If you use your boat solely for racing, it may be exempt from the requirement in your state. Some states may also exclude dinghies, while others require registration of documented vessels and non-power driven boats. All states, except Alaska, register boats. In Alaska, the Coast Guard issues the registration numbers. If you move your vessel to a new state of principal use, a valid registration certificate is good for 60 days. You must have the registration certificate (certificate of number) aboard your vessel when it is in use. A copy will not suffice. You may be cited if you do not have the original on board. NUMBERING OF VESSELS A registration number is on your registration certificate. You must paint or permanently attach this number to both sides of the forward half of your boat. Do not display any other number there. The registration number must be clearly visible. It must not be placed on the obscured underside of a flared bow. If you can't place the number on the bow, place it on the forward half of the hull. If that doesn't work, put it on the superstructure. Put the number for an inflatable boat on a bracket or fixture. Then, firmly attach it to the forward half of the boat. The letters and numbers must be plain block characters and must read from left to right. Use a space or a hyphen to separate the prefix and suffix letters from the numerals. The color of the characters must contrast with that of the background, and they must be at least three inches high. In some states your registration is good for only one year. In others, it is good for as long as three years. Renew your registration before it expires. At that time you will receive a new decal or decals. Place them as required by state law. You should remove old decals before putting on the new ones. Some states require that you show only the current decal or decals. If your vessel is moored, it must have a current decal even if it is not in use. If your vessel is lost, destroyed, abandoned, stolen, or transferred, you must inform the issuing authority. If you lose your certificate of number or your address changes, notify the issuing authority as soon as possible. SALES AND TRANSFERS Your registration number is not transferable to another boat. The number stays with the boat unless its state of principal use is changed. HULL IDENTIFICATION NUMBER A Hull Identification Number (HIN) is like the Vehicle Identification Number (VIN) on your car. Boats built between November 1, 1972 and July 31, 1984 have old format Since August 1, 1984 a new format has been used. Your boat's HIN must appear in two places. If it has a transom, the primary number is on its starboard side within two inches of its top. If it does not have a transom or if it was not practical to use the transom, the number is on the starboard side. In this case, it must be within one foot of the stern and within two inches of the top of the hull side. On pontoon boats, it is on the aft crossbeam within one foot of the starboard hull attachment. Your boat also has a duplicate number in an unexposed location. This is on the boat's interior or under a fitting or item of hardware. LENGTH OF BOATS For some purposes, boats are classed by length. Required equipment, for example, differs with boat size. Manufacturers may measure a boat's length in several ways. Officially, though, your boat is measured along a straight line from its bow to its stern. This line is parallel to its keel. The length does not include bowsprits, boomkins, or pulpits. Nor does it include rudders, brackets, outboard motors, outdrives, diving platforms, or other attachments. CAPACITY INFORMATION See Figure 4 Manufacturers must put capacity plates on most recreational boats less than 20 feet long. Sailboats, canoes, kayaks, and inflatable boats are usually exempt. Outboard boats must display the maximum permitted horsepower of their engines. The plates must also show the allowable maximum weights of the people on board. And they must show the allowable maximum combined weights of people, and gear. lnboards and stern drives need not show the weight of their engines on their capacity plates. The capacity plate must appear where it is visible to the operator when underwav. This serves to remind of the of your boat under normal circumstances. You should ask vourself. mv boat loaded above its recommended capacity" and, my boat for the present sea and wind conditions?" If you are stopped by a legal authority, you may be cited if you are overloaded. GENERAL INFORMATION, SAFETY AND TOOLS ST, ANAHEIM, CALIF Fig. 4 A Coast Guard certification plate indicates the amount of occupants and gear appropriate for safe operation of the vessel CERTIFICATE OF COMPLIANCE See Figure 4 Manufacturers are required to put compliance plates on motorboats greater than 20 feet in length. The plates must say, "This boat," or "This equipment complies with the U. S. Coast Guard Safety Standards in effect on the date of certification." Letters and numbers can be no less than eighth of an inch high. At the manufacturer's option, the capacity and compliance plates may be combined. VENTILATION A cup of gasoline spilled in the bilge has the potential explosive power of 15 sticks of dynamite. This statement, commonly quoted over 20 years ago, may be an exaggeration; however, it illustrates a fact. Gasoline fumes in the bilge of a boat are highly explosive and a serious danger. They are heavier than air and will stay in the bilge until they are vented out. Because of this danger, Coast Guard regulations require ventilation on many powerboats. There are several ways to supply fresh air to engine and gasoline tank compartments and to remove dangerous vapors. Whatever the choice, it must meet Coast Guard standards. The following is not intended to be a complete discussion of the regulations. It is limited to the majority of recreational vessels. Contact your local Coast Guard office for further information. General Precautions Ventilation systems will not remove raw gasoline that leaks from tanks or fuel lines. If you smell gasoline fumes, you need immediate repairs. The best device for sensing gasoline fumes is your nose. Use it! If you smell gasoline in an engine compartment or elsewhere, don't start your engine. The smaller the compartment, the less gasoline it takes to make an explosive mixture. Ventilation for Open Boats In open boats, gasoline vapors are dispersed by the air that moves through them. So they are exempt from ventilation requirements. To be "open," a boat must meet certain conditions. Engine and fuel tank compartments and long narrow compartments that join them must be open to the atmosphere." This means they must have at least square inches of open area for each cubic foot of net compartment volume. The open area must be in direct contact with the atmosphere. There must also be no long, unventilated spaces open to engine and fuel tank compartments into which flames could extend. Ventilation for All Other Boats Powered and natural ventilation are required in an enclosed compartment with a permanently installed gasoline engine that has a starter motor. A compartment is exempt if its engine is open to the atmosphere. Diesel powered boats are also exempt. VENTILATION SYSTEMS There are two types of ventilation systems. One is "natural ventilation." In it, air circulates through closed spaces due to the boat's motion. The other type is "powered ventilation." In it, air is circulated by a motor-driven fan or fans. Natural Ventilation System Requirements A natural ventilation system has an air supply from outside the boat. The air supply may also be from a ventilated compartment or a compartment open to the atmosphere. Intake openings are required. In addition, intake ducts may be required to direct the air to appropriate compartments. The system must also have an exhaust duct that starts in the lower third of the compartment. The exhaust must be into another ventilated compartment or into the atmosphere. Each supply opening and supply duct, if there is one, must be above the usual level of water in the bilge. Exhaust openings and ducts must also be above the bilge water. Openings and ducts must be at least three square inches in area or two inches in diameter. Openings should be placed so exhaust gasses do not enter the fresh air intake. Exhaust fumes must not enter cabins or other enclosed, ventilated spaces. The carbon monoxide gas in them is deadly. Intake and exhaust openings must be covered by cowls or similar devices. These registers keep out rain water and water from breaking seas. Most often, intake registers face forward and exhaust openings aft. This aids the flow of air when the boat is moving or at anchor since most boats face into the wind when properly anchored. Power Ventilation System Requirements See Figure 5 Powered ventilation systems must meet the standards of a natural svstem. Thev must also have one or more exhaust blowers. The blower duct serve the exhaust duct for natural ventilation if fan blades do not obstruct the air flow when not powered. Openings in engine compartment, for carburetion are in addition to ventilation system requirements. Fig. 5 Typical blower and duct system to vent fumes from the engine compartment Coast Guard regulations require that your boat have certain equipment aboard. These requirements are minimums. Exceed them whenever you can. TYPES OF FIRES There are four common classes of fires: Class A-fires are of ordinary combustible materials such as paper or wood. Class B-fires involve gasoline, oil and grease. Class C-fires are electrical. Class D-fires involve ferrous metals 1-6 GENERAL INFORMATION. SAFETY AND TOOLS One of the greatest risks to boaters is fire. This is why it is so important to carry the correct number and type of extinguishers The best fire extinguisher for most boats is a Class B extinguisher. Never use water on Class B or Class C fires, as water spreads these types of fires. Additionally, you should never use water on a Class C fire as it may cause you to be electrocuted. EXTINGUISHERS See Figure 6 If your boat meets one or more of the following conditions, you must have at least one fire aboard. The conditions are: Inboard or sternbrive engines Closed compartments under seats where portable fuel tanks can be stored Double bottoms not sealed together or not completely filled with flotation materials Closed living spaces Closed stowage compartments in which combustible or flammable materials are stored Permanently installed fuel tanks Boat is 26 feet or more in length. Fig. 6 An approved fire extinguisher should be mounted close to the operator for emergency use Contents of Extinguishers Fire extinguishers use a variety of materials. Those used on boats usually contain dry chemicals, Halon, or Carbon Dioxide Dry chemical extinguishers contain chemical powders such as Sodium baking soda. Carbon dioxide is a colorless and odorless gas when released from an extinguisher. It is not poisonous but caution must be used in entering compartments filled with it. It will not support life and keeps oxygen from reaching your lungs. A fire-killing concentration of Carbon Dioxide can be lethal. If you are in a compartment with a high concentration of C02, you will have no difficulty breathing. But the air does not contain enough oxygen to support life. Unconsciousness or death can result. Halon Extinguishers Some fire extinguishers and 'built-in' or 'fixed' automatic fire extinguishing systems contain a gas called Halon. Like carbon dioxide it is colorless and odorless and will not support life. Some Halons may be toxic if inhaled. To be accepted by the Coast Guard, a fixed Halon system must have an indicator light at the vessel's helm. A green light shows the system is ready. Red means it is being discharged or has been discharged. Warning horns are available to let you know the system has been activated. If your fixed Halon system discharges, ventilate the space thoroughly before you enter it. There are no residues from Halon but it will not support life. Although Halon has excellent fire fighting properties; it is thought to deplete the earth's ozone layer and has not been manufactured since January 1994. Halon extinguishers can be refilled from existing stocks of the gas until they are used up, but high federal excise taxes are being charged for the service. If you discontinue using your Halon extinguisher, take it to a recovery station rather than releasing the gas into the atmosphere. Compounds such as FE 241, designed to replace Halon, are now available. Fire Extinguisher Approval Fire extinguishers must be Coast Guard approved. Look for the approval number on the nameplate. Approved extinguishers have the following on their labels: "Marine Type USCG Approved, Size Type 162.2081," etc. In addition, to be acceotable bv the Coast Guard, an extinauisher must be in serviceable and in its bracket. An not mounted in its bracket will not be considered serviceable durina a inspection. Care and Treatment Make certain your extinguishers are in their stowage brackets and are not damaged. Replace cracked or broken hoses. Nozzles should be free of obstructions. Sometimes, wasps and other insects nest inside nozzles and make them inoperable. Check your extinguishers frequently. If they have pressure gauges, is the pressure within acceptable limits? Do the locking pins and sealing wires show they have not been used since recharging? Don't try an extinguisher to test it. Its valves will not properly and the remaining gas will leak out. When this happens, the extinguisher is useless. Weigh and tag carbon dioxide and Halon extinguishers twice a year. If their weight loss exceeds 10 percent of the weight of the charge, recharge them. Check to see that they have not been used. They should have been inspected by a qualified person within the past six months, and they should have tags showing all inspection and service dates. The problem is that they can be partially discharged while appearing to be fully charged. Some Halon extinguishers have pressure gauges the same as dry chemical extinguishers. Don't rely too heavily on the gauge. The extinguisher can be partially and still show a good gauge reading. Weighing a Halon extinguisher is the only accurate way to assess its contents. If your dry chemical extinguisher has a pressure indicator, check it frequently. Check the nozzle to see if there is powder in it. If there is, recharge it. Occasionally invert your dry chemical extinguisher and hit the base with the palm of your hand. The chemical in these extinguishers packs and cakes due to the boat's vibration and pounding. There is a difference of opinion about whether hitting the base helps, but it can't hurt. It is known that caking of the chemical powder is a major cause of failure of dry chemical extinguishers. Carry spares in excess of the minimum requirement. If you have guests aboard, make certain they know where the extinguishers are and how to use them. Using a Fire Extinguisher A fire extinguisher usually has a device to keep it from being discharged accidentally. This is a metal or plastic pin or loop. If you need to use your extinguisher, take it from its bracket. Remove the pin or the loop and point the nozzle at the base of the flames. Now, squeeze the handle, and discharge the extinguisher's contents while sweeping from side to side. Recharge a used extinguisher as soon as possible. If you are using a Halon or carbon dioxide extinguisher, keep your hands away from the discharge. The rapidly expanding gas will freeze them. If your fire extinguisher has a horn, hold it by its handle. Legal Requirements for Extinguishers You must carry fire extinguishers as defined by Coast Guard regulations. They must be firmly mounted in their brackets and immediately accessible. A motorboat less than 26 feet long must have at least one approved hand-portable, Type extinguisher. It the boat has an approved fire extinguishing system, you are not required to have the Type B-I extinguisher. GENERAL INFORMATION. SAFETYANDTOOLS 1-7 Also, if your boat is less than 26 feet long, is propelled by an outboard motor, or motors, and does not have any of the first six conditions described at the beginning of this section, it is not required to have an extinguisher. Even so, it's a good idea to have one, especially if a nearby boat catches fire, or if a fire occurs at a fuel dock. A motorboat 26 feet to under 40 feet long, must have at least two Type B- approved hand-portable extinguishers. It can, instead, have at least one Coast Guard approved Type If you have an approved fire extinguishing system, only one Type B-1 is required. A motorboat 40 to 65 feet long must have at least three Type B-1 approved portable extinguishers. It may have, instead, at least one Type B-1 plus a Type If there is an approved fixed fire extinguishing system, two Type or one Type is required. WARNING SYSTEM Various devices are available to alert you to danger. These include fire, smoke, gasoline fumes, and carbon monoxide detectors. If your boat has a galley, it should have a smoke detector. Where possible, use wired detectors. Household batteries often corrode rapidly on a boat. There are many ways in which carbon monoxide (a by-product of the combustion that occurs in an engine) can enter your boat. You can't see, smell, or taste carbon monoxide gas, but is lethal. As little as one part in 10,000 parts of air can bring on a headache. The symptoms of carbon monoxide poisoning-headaches, dizziness, and nausea-are like seasickness. By the time you realize what is happening to you, it may be too late to take action. If you have enclosed living spaces on your boat, protect yourself with a detector. PERSONAL FLOTATION DEVICES Personal Flotation Devices (PFDs) are commonly called life preservers or life jackets. You can get them in a variety of types and sizes. They vary with their intended uses. To be acceptable, PFDs must be Coast Guard approved. Type PFDs A Type I life jacket is also called an offshore life jacket. Type I life jackets will turn most unconscious from facedown to a vertical or backward position. The adult gives a minimum of 22 pounds of" buovancv. The child size has at least ' I iackets more to their wearers than any type of jacket. I life jackets are bulkier and less comfortable than other types. Furthermore, there are only two sizes, one for children and one for adults. Type I life jackets will keep their wearers afloat for extended periods in rough water. They are recommended for offshore cruising where a delayed rescue is probable. Type PFDs + See Figure 7 A Type life jacket is also called a near-shore buoyant vest. It is an approved, wearable device. Type life jackets will turn some unconscious people from facedown to vertical or slightly backward positions. The adult size gives at least 15.5 pounds of buoyancy. The medium child size has a minimum of 11 pounds. And the small child and infant sizes give seven pounds. A life iacket is more comfortable than a I but it does not have as buoyancy. It is not recommended for long hours in rough water. Because of this. are recommended for inshore and inland cruising on calm water. them only where there is a good chance of fast rescue. Type PFDs Type life jackets or marine buoyant devices are also known as flotation aids. Like Type they are designed for calm inland or close offshore water where there is a good chance of fast rescue. Their minimum buoyancy is 15.5 pounds. They will NOT turn their wearers face up. Type devices are usually worn where freedom of movement is necessary. Thus, they are used for water skiing, small boat sailing, and fishing among other activities. They are available as vests and flotation coats. Flotation coats are useful in cold weather. Type come in many sizes from small child through large adult. Life jackets come in a variety of colors and patterns-red, blue, green, camouflage, and cartoon characters. From purely a safety standpoint, the best color is bright orange. It is easier to see in the water, especially if the water is rough. Type PFDs + See Figures 8 and 9 Type ring life buoys, buoyant cushions and horseshoe buoys are Coast Guard approved devices called throwables. They are made to be thrown to people in the water, and should not be worn. Type cushions are often used as seat cushions. But, keep in mind that cushions are hard to hold onto in the water, thus, they do not afford as much protection as wearable life jackets. The straps on buoyant cushions are for you to hold onto either in the water or when throwing them, they are NOT for your arms. A cushion should never be worn on your back, as it will turn you face down in the water. Type throwables are not designed as personal flotation devices for unconscious people, non-swimmers, or children. Use them only in emergencies. They should not be used for, long periods in rough water. Ring life buoys come in 18, and 30 inch diameter sizes. They usually have grab lines, but you will need to attach about 60 feet of polypropylene line to the grab rope to aid in retrieving someone in the water. If you throw a ring, be careful not to hit the person. Ring buoys can knock people unconscious Type V PFDs Type V PFDs are of two kinds, special use devices and hybrids. Special use devices include boardsailing vests, deck suits, work vests, and others. They are approved only for the special uses or conditions indicated on their labels. Each is designed and intended for the particular application shown on its label. They do not meet legal requirements for general use aboard recreational boats. Hybrid life jackets are inflatable devices with some built-in buoyancy provided by plastic foam or kapok. They can be inflated orally or by cylinders of compressed gas to give additional buoyancy. In some hybrids the gas is released manually. In others it is released automatically when the life jacket is immersed in water. The inherent buoyancy of a hybrid may be insufficient to float a person unless it is inflated. The only way to find this out is for the user to try it in the water. Because of its limited buoyancy when deflated, a hybrid is recommended for use by a non-swimmer only if it is worn with enough inflation to float the wearer. If they are to count against the legal requirement for the number of life jackets you must carry, hybrids manufactured before February 8, 1995 must be worn whenever a boat is underway and the wearer must not go below decks or in an enclosed space. To find out if your Type V hybrid must be worn to satisfy the legal requirement, read its label. If its use is restricted it will say, "REQUIRED TO BE WORN" in capital letters. Hybrids cost more than other life jackets, but this factor must be weighed against the fact that they are more comfortable than Types I, or life jackets. Because of their greater comfort, their owners are more likely to wear them than are the owners of Type I, or life jackets. The Coast Guard has determined that improved, less costly hybrids can save lives since they will be bought and used more frequently. For these reasons, a new federal regulation was adopted effective February 8, 1995. The regulation increases both the deflated and inflated buoyancys of hybrids, makes them available in a greater variety of sizes and types, and reduces their costs by reducing production costs. Even though it may not be required, the wearing of a hybrid or a life jacket is encouraged whenever a vessel is underway. Like life jackets, hybrids are now available in three types. To meet legal requirements, a Type I hybrid can be substituted for a Type I life jacket. Similarly Type and hybrids can be substituted for Type and Type life jackets. I hybrid, when inflated, will turn most unconscious people from facedown to vertical or slightly backward positions just like a Type I life jacket. Type and hybrids function like Type and life jackets. If you purchase a new hybrid, it should have an owner's manual attached that describes its life jacket type and its deflated and inflated buoyancys. It warns you that it may have to be inflated to float you. The manual also tells you how to don the life jacket and how to inflate it. It also tells you how to change its inflation mechanism, recommended testing exercises, and inspection or maintenance procedures. 1-8 GENERAL INFORMATION, SAFETY AND TOOLS Fig. 7 Type are recommended for Fig. 9 Type throwables, such as this ring Fig. 8 Type buoyant cushions are thrown inshore and inland cruising on calm water life buoy, are not designed for unconscious to people in the water. if you can squeeze air (where there is a good chance of fast rescue) people, non-swimmers, or children out of the cushion, it should be replaced The manual also tells you why you need a life jacket and why you should wear it. A new hybrid must be packaged with at least three gas cartridges. One of these may already be loaded into the inflation mechanism. Likewise, if it has an automatic inflation mechanism, it must be packaged with at least three of these water sensitive elements. One of these elements may be installed. Legal Requirements A Coast Guard approved life jacket must show the manufacturer's name and approval number. Most are marked as Type I, 11, or V. All of the newer hybrids are marked for type. You are required to carry at least one wearable life jacket or hybrid for each person on board your recreational vessel. If your vessel is 16 feet or more in length and is not a canoe or a kayak, you must also have at least one Type on board. These requirements apply to all recreational vessels that are propelled or controlled by machinery, sails, oars, paddles, poles, or another vessel. Sailboards are not required to carry life jackets. You can substitute an older Type V hybrid for any required Type I, or life jacket provided: Its approval label shows it is approved for the activity the vessel is engaged in 2. It's approved as a substitute for a life jacket of the type required on the vessel 3. It's used as required on the labels and 4. It's used in accordance with any requirements in its owner's manual (if the approval label makes reference to such a manual.) A water skier being towed is considered to be on board the vessel when judging compliance with legal requirements. You are required to keep your Type I, or life jackets or equivalent hybrids readily accessible, which means you must be able to reach out and get them when needed. All life jackets must be in good, serviceable condition. General Considerations The proper use of a life jacket requires the wearer to know how it will perform. You can gain this knowledge only through experience. Each person on your boat should be assigned a life jacket. Next, it should be fitted to the person who will wear it. Only then can you be sure that it will be ready for use in an emergency. This advice is good even if the water is calm, and you intend to boat near shore. Boats can sink fast. There may be no time to look around for a life jacket. Fitting one on you in the water is almost impossible. Most drownings occur in inland waters within a few feet of safety. Most victims had life jackets, but they weren't wearing them. Keeping life jackets in the plastic covers they came wrapped in, and in a cabin, assures that they will stay clean and unfaded. But this is no way to keep them when you are on the water. When you need a life jacket it must be readily accessible and adjusted to fit you. You can't spend time hunting for it or learning how to fit it. There is no substitute for the experience of entering the water while wearing a life jacket. Children, especially, need practice. If possible, give your guests this experience. Tell them they should keep their arms to their sides when jumping in to keep the life jacket from riding up. Let them jump in and see how the life jacket responds. Is it adjusted so it does not ride up? Is it the proper size? Are all straps snug? Are children's life jackets the right sizes for them? Are they adjusted properly? If a child's life jacket fits correctly, you can lift the child by the jacket's shoulder straps and the child's chin and ears will not slip through. Non-swimmers, children, handicapped persons, elderly persons and even pets should always wear life jackets when they are aboard. Many states require that everyone aboard wear them in hazardous waters. Inspect your lifesaving equipment from time to time. Leave any questionable or unsatisfactory equipment on shore. An emergency is no time for you to conduct an inspection. Indelibly mark your life jackets with your vessel's name, number, and calling port. This can be important in a search and rescue effort. It could help concentrate effort where it will do the most good. Care of Life Jackets Given reasonable care, life jackets last many years. Thoroughly dry them before putting them away. Stow them in dry, well-ventilated places. Avoid the bottoms of lockers and deck storage boxes where moisture may collect. Air and dry them frequently. Life jackets should not be tossed about or used as fenders or cushions. Many contain kapok or fibrous glass material enclosed in plastic bags. The bags can rupture and are then unserviceable. Squeeze your life jacket gently. Does air leak out? If so, water can leak in and it will no longer be safe to use. Cut it up so no one will use it, and throw it away. The covers of some life jackets are made of nylon or polyester. These materials are plastics. Like many plastics, they break down after extended exposure to the ultraviolet light in sunlight. This process may be more rapid when the materials are dyed with bright dyes such as "neon" shades. Ripped and badly faded fabrics are clues that the covering of your life jacket is deteriorating. A simple test is to pinch the fabric between your thumbs and forefingers. Now try to tear the fabric. If it can be torn, it should definitely be destroyed and discarded. Compare the colors in protected places to those exposed to the sun. If the colors have faded, the materials have been weakened. A life jacket covered in fabric should ordinarily last several boating seasons with normal use. A life jacket used every day in direct sunlight should probably be replaced more often. SOUND PRODUCING DEVICES All boats are required to carry some means of making an efficient sound signal. Devices for making the whistle or horn noises required by the Navigation Rules must be capable of a four-second blast. The blast should be audible for at least one-half mile. Athletic whistles are not acceptable on boats 12 meters or longer. Use caution with athletic whistles. When wet, some of them come apart and loose their "pea." When this happens, they are useless. If your vessel is 12 meters long and less than 20 meters, you must have a power whistle (or power horn) and a bell on board. The bell must be in operating condition and have a minimum diameter of at least (7.9 in.) at its mouth. GENERAL INFORMATION, SAFETY AND TOOLS 1-9 VISUAL DISTRESS SIGNALS See Figure 10 Visual Distress Signals (VDS) attract attention to your vessel if you need help. They also help to guide searchers in search and rescue situations. Be sure you have the right types, and learn how to use them properly. It is illegal to fire flares improperly. In addition, they cost the Coast Guard and its Auxiliary many wasted hours in fruitless searches. If you signal a distress with flares and then someone helps you, please let the Coast Guard or the appropriate Search And Rescue (SAR) Agency know so the distress report will be canceled. Recreational boats less than 16 feet long must carry visual distress signals on coastal waters at night. Coastal waters are: The ocean (territorial sea) The Great Lakes Bays or sounds that empty into oceans Rivers over two miles across at their mouths upstream to where they narrow to two miles. Recreational boats 16 feet or longer must carry VDS at all times on coastal waters. The same requirement applies to boats carrying six or fewer passengers for hire. Open sailboats less than 26 feet long without engines are exempt in the daytime as are manually propelled boats. Also exempt are boats in organized races, regattas, parades, etc. Boats owned in the United States and operating on the high seas must be equipped with VDS. A wide variety of signaling devices meet Coast Guard regulations. For pyrotechnic devices, a minimum of three must be carried. Any combination can be carried as long as it adds up to at least three signals for day use and at least three signals for night use. Three signals meet both requirements. If possible, carry more than the legal requirement. The American flag flying upside down is a commonly recognized distress signal. It is not recognized in the Coast Guard regulations, though. In an emergency, your efforts would probably be better used in more effective signaling methods. Types of VDS VDS are divided into two groups; daytime and nighttime use. Each of these groups is subdivided into pyrotechnic and non-pyrotechnic devices. Daytime Non-Pyrotechnic Signals A bright orange flag with a black square over a black circle is the simplest VDS. It is usable, of course, only in daylight. It has the advantage of being a continuous signal. A mirror can be used to good advantage on sunny days. It can attract the attention of other boaters and of aircraft from great distances. 10 Internationally accepted distress signals Fig. 11 Moisture protected flares should be carried any vessel for use as a distress signal Mirrors are available with holes in their centers to aid in "aiming." In the absence of a mirror, any shiny object can be used. When another boat is in sight, an effective VDS is to extend your arms from your sides and move them up and down. Do it slowly. If you do it too fast the other people may think you are just being friendly. This simple gesture is seldom misunderstood, and requires no equipment. Daytime Pyrotechnic Devices Orange smoke is a useful daytime signal. Hand-held or floating smoke flares are very effective in attracting attention from aircraft. Smoke flares don't last long, and are not very effective in high wind or poor visibility. As with other pyrotechnic devices, use them only when you know there is a possibility that someone will see the display. To be usable, smoke flares must be kept dry. Keep them in airtight containers and store them in dry places. If the "striker" is damp, dry it out before trying to ignite the device. Some pyrotechnic devices require a forceful "strike" to ignite them. All hand-held pyrotechnic devices may produce hot ashes or slag when burning. Hold them over the side of your boat in such a way that they do not burn your hand or drip into your boat. Nighttime Non-Pyrotechnic Signals An electric distress light is available. This light automatically flashes the international morse code SOS distress signal ). Flashed four to six times a minute, it is an unmistakable distress signal. It must show that it is approved by the Coast Guard. Be sure the batteries are fresh. Dated batteries give assurance that they are current. Under the Inland Navigation Rules, a high intensity white light flashing 50-70 times per minute is a distress signal. Therefore, use strobe lights on inland waters only for distress signals. Nighttime Pyrotechnic Devices See Figure 11 Aerial and hand-held flares can be used at night or in the daytime. Obviously, they are more effective at night. Currently, the serviceable life of a pyrotechnic device is rated at 42 months from its date of manufacture. Pyrotechnic devices are expensive. Look at their dates before you buy them. Buy them with as much time remaining as possible. Like smoke flares, aerial and hand-held flares may fail to work if they have been damaged or abused. They will not function if they are or have been wet. Store them in dry, airtight containers in dry places. But store them where they are readily accessible. . . I I aid kit board for the the to secure the boat without dragging I I a pair of pliers can be very helpful to crew and guests make emergency repairs , . ... . .. . . 12 Alwavs carrv an adeauatelv stocked a Aerial depending on their type and the conditions they are used in, may not go very high. Again, use them only when there is a good chance they will be seen. A serious disadvantage of aerial flares is that they burn for only a short time; most burn for less than seconds. Most parachute flares burn for less than 45 seconds. If you use a VDS in an emergency, do so carefully. Hold hand-held flares over the side of the boat when in use. Never use a road hazard flare on a boat, it can easily start a fire. Marine type flares are specifically designed to lessen risk, but they still must be used carefully. Aerial flares should be given the same respect as firearms since they are firearms! Never point them at another person. Don't allow children to play with them or around them. When fire one, face from the wind. Aim it downwind and upward at an angle of about 60 degree's to the horizon. If there is a strong wind, aim it somewhat more vertically.Never fire it straight up. Before you discharge a flare pistol, check for overhead obstructions that miaht be damaaed bv the flare. An obstruction miaht deflect the flare to it will or damage. Disposal of VDS Keep outdated flares when you get new ones. They do not meet legal requirements,but you might need them sometime, and they may work. It is illegal to fire a VDS on federal navigable waters unless an emergency exists. Many states have similar laws. Emergency Position Radio Beacon (EPIRB) There is no requirement for recreational boats to have Some commercial and fishing vessels, though, must have them if they operate beyond the three-mile limit. Vessels carrying six or fewer passengers for hire must have under some circumstances when operating beyond the three-mile limit. If you boat in a remote area or offshore, you should have an EPIRB. An is a small (about 6 to 20 inches high), battery-powered, radio transmitting buoy-like device. It is a radio transmitter and requires a license or an endorsement on your radio station license by the Federal Communications Commission (FCC). are either automatically activated by being immersed in water or manually by a switch. Although not required by law, there are other pieces of equipment that are good to have SECOND MEANS OF PROPULSION All boats less than 16 feet long should carry a second means of propulsion. A paddle or oar can come in handy at times. For most small boats, a spare trolling or outboard motor is an excellent idea. If you carry a spare motor, it should have its own fuel tank and starting power. If you use an electric trolling motor, it should have its own battery. BAILING DEVICES All boats should carry at least one effective manual bailing device in addition to any installed electric bilge pump. This can be a bucket, can, scoop, hand-operated pump, etc. If your battery "goes dead" it will not operate your electric pump. FIRST AID KIT + See Figure 12 All boats should carry a first aid kit. It should contain adhesive bandages, gauze, adhesive tape, antiseptic, aspirin, etc. Check your first aid kit from time to time. Replace anything that is outdated. It is to your advantage to know how to use your first aid kit. Another good idea would be to take a Red Cross first aid course. ANCHORS See Figure 13 All boats should have anchors. Choose one of suitable size for your boat. Better still, have two anchors of different sizes. Use the smaller one in calm water or when anchoring for a short time to fish or eat. Use the larger one when the water is rougher or for overnight anchoring. Carry enough anchor line, of suitable size, for your boat and the waters in which you will operate. If your engine fails you, the first thing you usually should do is lower your anchor. This is good advice in shallow water where you may be driven aground by the wind or water. It is also good advice in windy weather or rough water, as the anchor, when properly affixed, will usually hold your bow into the waves. VHF-FM RADIO Your best means of summoning help in an emergency or in case of a breakdown is a VHF-FM radio. You can use it to get advice or assistance from the Coast Guard. In the event of a serious illness or injury aboard your boat, the Coast Guard can have emergency medical equipment meet you ashore. TOOLS AND SPARE PARTS See Figures 14 and 15 Carry a few tools and some spare parts, and learn how to make minor repairs. Many search and rescue cases are caused by minor breakdowns that boat operators could have repaired. Carry spare parts such as propellers, fuses or basic ignition components (like spark plugs, wires or even ignition coils) and the tools necessary to install them. Fig. 15 A flashlight with a fresh set of batteries is handy when repairs are needed at night. It can also double as a signaling device GENERAL INFORMATION, SAFETY AND TOOLS 1-11 is be told to the One of the roles of the Coast Guard Auxiliary is to promote recreational If your vessel qualifies, you will be awarded a safety decal. The decal boating safety. This is why they conduct thousands of Courtesy Marine does not carry any special privileges, it simply attests to your interest in safe Examinations each year. The auxiliarists who do these examinations are boating. well-trained and knowledgeable in the field. These examinations are free and done only at the consent of boat owners. To pass the examination, a vessel must satisfy federal equipment requirements and certain additional requirements of the coast guard auxiliary. If your vessel does not pass the Courtesy Marine Examination, no It is virtually impossible to anticipate all of the hazards involved with maintenance and service, but care and common sense will prevent most accidents. The rules of safety for mechanics range from "don't smoke around gasoline," to "use the proper for the job." The trick to avoiding injuries is to develop safe work habits and to take every possible precaution. Whenever you are working on your boat, pay attention to what you are doing. The more you pay attention to details and what is going on around you, the less likely you will be to hurt yourself or damage your boat. Do keep a fire extinguisher and first aid kit handy. Do wear safety glasses or goggles when cutting, drilling, grinding or prying, even if you have 20-20 vision. If you wear glasses for the sake of vision, wear safety goggles over your regular glasses. Do shield your eyes whenever you work around the battery. Batteries contain sulfuric acid. In case of contact with the eyes or skin, flush the area with water or a mixture of water and baking soda; then seek immediate medical attention. Do use adequate ventilation when working with any chemicals or hazardous materials. Do disconnect the negative battery cable when working on the electrical system. The secondary ignition system contains EXTREMELY VOLTAGE. In some cases it can even exceed 50,000 volts. Furthermore, an accidental attempt to start the engine could cause the propeller or other components to rotate suddenly causing a potentially dangerous situation. Do follow manufacturer's directions whenever working with potentially hazardous materials. Most chemicals and fluids are poisonous if taken internally. Do properly maintain your tools. Loose hammerheads, mushroomed punches and chisels, frayed or poorly grounded electrical cords, excessively worn screwdrivers, spread wrenches (open end), cracked sockets, or slipping ratchets can cause accidents. Likewise, keep your tools clean; a greasy wrench can slip off a bolt head, ruining the bolt and often harming your knuckles in the process. Do use the proper size and type of tool for the job at hand. Do select a wrench or socket that fits the nut or bolt. The wrench or socket should sit straight, not cocked. Do, when possible, pull on a wrench handle rather than push on it, and adjust your stance to prevent a fall. Do be sure that adjustable wrenches are tightly closed on the nut or bolt and pulled so that the force is on the side of the fixed jaw. Better yet, avoid the use of an adjustable if you have a fixed wrench that will fit. Do strike squarely with a hammer; avoid glancing blows. Do use common sense whenever you work on your boat or motor. If a situation arises that doesn't seem right, sit back and have a second look. It may save an embarrassing moment or potential damage to your beloved boat. Don't run the engine in an enclosed area or anywhere else without proper ventilation-EVER! Carbon monoxide is poisonous; it takes a long time to leave the human body and you can build up a deadly supply of it in your system by simply breathing in a little every day. You may not realize you are slowly poisoning yourself. Don't work around moving parts while wearing loose clothing. Short sleeves are much safer than long, loose sleeves. Hard-toed shoes with neoprene soles protect your toes and give a better grip on slippery surfaces. Jewelry, watches, large belt buckles, or body adornment of any kind is not safe workina around anv craft or vehicle. Lona hair should be tied back under a hat: Don't use for toolboxes. A fall or can drive a screwdriver deep into your body. Even a rag hanging from back pocket can around a spinning shaft. Don't smoke when working around gasoline, cleaning solvent or other flammable material. Don't smoke when working around the battery. When the battery is being charged, it gives off explosive hydrogen gas. Actually, you shouldn't smoke anyway. Save the cigarette money and put it into your boat! Don't use gasoline to wash your hands; there are excellent soaps available. Gasoline contains dangerous additives that can enter the body through a cut or through your pores. Gasoline also removes all the natural oils from the skin so that bone dry hands will suck up oil and grease. Don't use screwdrivers for anything other than driving screws! A screwdriver used as an prying tool can snap when you least expect it, causing injuries. At the very least, you'll ruin a good screwdriver. Troubleshooting can be defined as a methodical process during which one discovers what is causina a oroblem with enaine Althouah it is often a feared process to there reason to believe you cannot figure out what is wrong with an engine, as long as you follow a few basic rules. To begin with, troubleshooting must be systematic. Haphazardly testing one component, then another, uncover the problem, but it will more likely waste a lot of time. True troubleshooting starts by defining the problem and performing systematic tests to eliminate the largest and most likely causes first. Start all troubleshooting by eliminating the most basic possible causes; begin with a visual inspection of the boat, engine and drive. If the engine won't crank, make sure that the kill switch or safety lanyard is in the proper position. Make sure there is fuel in the tank and the fuel system is primed before condemning the carburetor or fuel injection system. Make sure there are no blown fuses, the battery is fully charged, and the cable connections (at both ends) are clean and tight before suspecting a bad starter, solenoid or switch. The majority of problems that occur suddenly can be fixed by simply identifying the one small item that brought them on. A loose wire, a clogged passage or a broken component can cause a lot of trouble and are often the cause of a sudden performance problem. The next most basic step in troubleshooting is to test systems before components. For example, if the engine doesn't crank on an electric start motor, determine if the battery is in good condition (fully charged and properly connected) before testing the starting system. If the engine cranks, but doesn't start, you know already know the starting system and battery (if it cranks fast enough) are in good condition, now it is time to look at the ignition or fuel systems. Once you've isolated the problem to a particular system, follow the procedures in the section for that system to test either sub-systems (if applicable, for example: the starter circuit) or components (starter solenoid). 1-12 GENERAL INFORMATION, SAFETY AND TOOLS . a a the in See Figures 16 and 17 Before attempting to troubleshoot a problem with your engine, it is important that you understand how it operates. Once normal engine or system operation is understood, it will be easier to determine what might be causing the trouble or irregular operation in the first place. System descriptions are found throughout this manual, but the basic mechanical operating principles for both 2-stroke engines and 4-stroke engines (like are aiven here. A basic understandina of both of enaines is useful not in understanding and OMC,but also for dealing with other motors in your life. All engines covered by this manual (and probably MOST of the motors you own) operate according to the Otto cycle principle of engine operation. This means that all engines follow the stages of intake, compression, power 2-stroke motors (as the name suggests) the cycles take in 2 movements (one up and one down) of the piston. Again, as the name suggests, the cycles take place in 4 movements of the piston for 4-stroke engines. 2-STROKE MOTORS The 2-stroke engine differs in several ways from a conventional stroke (automobile or marine) engine. The method bv which the fuel-air mixture is delivered to the combustion chamber. 2. The complete lubrication system. 3. The frequency of the power stroke. Let's discuss these differences briefly (and compare 2-stroke engine operation with 4-stroke engine operation.) Deflector Piston I Exhaust , Intake port Intake Compression Reed rod Ignition power stroke Fig. 16 The complete piston cycle of a 2-stroke motor (intake, compression, power and exhaust) closed Exhaust Fig. 17 The complete piston cycle of a engine (intake, compression, power and exhaust) Compression 3. Ignition 4. Exhaust GENERAL INFORMATION, SAFETY AND TOOLS See Figure 18 Two-stroke engines utilize an arrangement of port openings to admit fuel to the combustion chamber and to purge the exhaust gases after burning has been completed. The ports are located in a precise pattern in order for them to be open and closed off at an exact moment by the piston as it moves up and down in the cylinder. The exhaust port is located slightly higher than the fuel intake port. This arrangement opens the exhaust port first as the piston starts downward and therefore, the exhaust phase begins a fraction of a second before the intake phase. Actually, the intake and exhaust are spaced so closely together that both open almost simultaneously. For this reason, many 2-stroke engines utilize deflector-type pistons. This design of the piston top serves two purposes very effectively. First, it creates turbulence when the incoming charge of fuel enters the combustion chamber. This turbulence results in a more complete burning of the fuel than if the piston top were flat. The second effect of the type piston crown is to force the exhaust gases from the cylinder more rapidly. These systems of intake and exhaust are in marked contrast to individual mechanical of utilize valve train employed by most some it is verv 2-stroke that engines use a circular valve or rotating disc that contains a port opening around part of one edge of the disc. As the engine (and disc) turns, the opening aligns with the intake port at and for a predetermined amount of time, closing off the port again as the opening passes by and the solid portion of the disc covers the port. Lubrication A 2-stroke engine is lubricated by mixing oil with the fuel. Therefore, various parts are lubricated as the fuel mixture passes through the crankcase and the cylinder. In contrast, four-stroke engines have a crankcase containing oil. This oil is pumped through a circulating system and returned to the crankcase to begin the routing again Power Stroke The combustion cycle of a 2-stroke engine has four distinct phases lntake 2. Compression 3. Power It should 4. Exhaust I n Exhaust 'lntake port Intake Exhaust Fig. 18 The intake and exhaust cycles of a two-stroke Cross flow (CV) design shown The four phases of the cycle are accomplished with each up and down stroke of the piston, and the power stroke occurs with each complete revolution of the crankshaft. Compare this system with a four-stroke engine. A separate stroke of the piston is required to accomplish each phase of the cycle and the power stroke occurs only every other revolution of the crankshaft. Stated another way, two revolutions of the four-stroke engine crankshaft are required to complete one full cycle, the four phases. Physical Laws See Figure 19 The 2-stroke enaine is able to function because of two verv simple . . physical laws. One: Gases will flow from an area of pressure to an area of lower pressure. A tire blowout is an example of The high-pressure air escapes if the tube is TWO: If a is compressed into a smaller area, the pressure increases, and if a gas expands into a larger area, the pressure is decreased. If these two laws are kept in mind, the operation of the 2-stroke engine will be easier understood. Induced low air pressure \ Atmospheric air pressure Fig. 19 Air flow principal for a modern carburetor. Operation See Figure 16 The engine described here is of a carbureted type. Beginning with the piston approaching top dead center on the compression stroke: the intake and exhaust ports are physically closed (blocked) by the piston. During this stroke, the reed valve is open (because as the piston moves upward, the crankcase volume increases, which reduces the crankcase to less than the outside (creates a vacuum the piston). The spark plug fires; the compressed fuel-air mixture is ignited; and the power stroke begins. As the piston moves downward on the power stroke, the combustion chamber is filled with burning gases. As the exhaust port is uncovered, the gases, which are under great pressure, escape rapidly through the exhaust ports. The piston continues its downward movement. Pressure within the crankcase (again, under the piston) increases, closing the reed valves against their seats. The crankcase then becomes a sealed chamber so the air-fuel mixture becomes compressed (pressurized) and ready for delivery to the combustion chamber. As the piston continues to move downward, the intake port is uncovered. The fresh fuel mixture rushes through the intake port into the combustion chamber striking the top of the piston where it is deflected along the cylinder wall. The reed valve remains closed until the piston moves upward again. When the piston begins to move upward on the compression stroke, the reed valve opens because the crankcase volume has been increased, 1-14 GENERAL INFORMATION, SAFETY AND TOOLS reducing crankcase pressure to less than the outside atmosphere. The intake and exhaust ports are closed and the fresh fuel charge is compressed inside the combustion chamber. Pressure in the crankcase (beneath the piston) decreases as the piston moves upward and a fresh charge of air flows through the carburetor picking up fuel. As the piston approaches top dead center, the spark plug ignites the air-fuel mixture, the power stroke begins and one complete Otto cycle has been completed. 4-STROKE ENGINES The engine may be easier to understand for some people, either because of its prevalence in automobile and street motorcycle engines today, or perhaps because each of the four strokes corresponds to one distinct phase of the Otto cycle. Essentially, a engine completes one Otto cycle of intake, compression, ignitionlpower and exhaust using two full revolutions of the crankshaft and four distinct movements of the piston (down, up, down and up). lntake The intake stroke begins with the piston near the top of its travel. As crankshaft rotation begins to pull the piston downward, the exhaust valve closes and the intake opens. As volume of the combustion chamber increases, a vacuum is created that draws in the airlfuel mixture from the intake manifold. Compression Once the piston reaches the bottom of its travel, crankshaft rotation will begin to force it upward. At this point the intake valve closes. As the piston rises in the bore, the volume of the sealed (both intake and exhaust valves are closed) combustion chamber decreases and the airlfuel mixture is compressed. This raises the temperature and pressure of the mixture and increases the amount of force generated by the expanding gases during the stroke. As the piston approaches top dead center (the highest point of travel in the bore), the spark plug will fire, igniting the airlfuel mixture. The resulting combustion of the airlfuel mixture forces the piston downward, rotating the crankshaft (causing other pistons to move in other phaseslstrokes of the Otto cycle on multi-cylinder engines). Exhaust As the piston approaches the bottom of the stroke, the exhaust valve opens. When the piston begins its upward path of travel once again, any remaining unburned gasses are forced out through the exhaust valve. This completes one Otto cycle, which begins again as the piston passes top dead center, the intake valve opens and the Intake stroke starts. COMBUSTION Whether we are talking about a 2-or engine, all Otto cycle, internal combustion engines require three basic conditions to operate properly, Compression 2. (Spark), 3. A lack of any one of these conditions will prevent the engine from operating. A problem with any one of these will manifest itself in hard-starting or poor performance. Compression An engine that has insufficient compression will not draw an adequate supply of airlfuel mixture into the combustion chamber and, subsequently, will not make sufficient power on the power stroke. A lack of compression in just one cylinder of a multi-cylinder engine will cause the engine to stumble or run irregularly. But, keep in mind that a sudden change in compression is unlikely in stroke motors (unless something major breaks inside the crankcase, but that would usually be accompanied by other symptoms such as a loud noise when it occurred or noises during operation). On engines, a sudden change in compression is also unlikely, but could occur if the timing belt or chain was to suddenly break. Remember that the timing is used to synchronize the valve train with the crankshaft. If the valve train suddenly ceases to turn, some intake and some exhaust valves will remain open, relieving compression in that cylinder. Ignition (Spark) Traditionally, the ignition system is the weakest link in the chain of conditions necessary for engine operation. Spark plugs may become worn or fouled, wires will deteriorate allowing arcing or misfiring, and poor connections can place an undue load on coils leading to weak spark or even a failed coil. The most common question asked by a technician under a start condition is: "do I have spark and fuel" (as they've already determined that they have compression). A quick visual inspection of the spark will answer the question as to whether or not the islart worn or fouled. While the engine is shut OFFa physical check of the connections could show a loose primary or secondary ignition circuit wire. An obviously physically damaged wire may also be an indication of system problems and certainly encourages one to inspect the related system more closely. If nothing is turned up by the visual inspection, perform the Spark Test provided in the lgnition System section to determine if the problem is a lack of or a weak spark. If the problem is not compression or spark, it's time to look at the fuel system. Fuel If compression and spark is present (and within spec), but the engine won't start or won't run properly, the only remaining condition to fulfill is fuel. As usual, start with the basics. Is the fuel tank full? Is the fuel stale? If the engine has not been run in some time (a matter of months, not weeks), there is a good chance that the fuel is stale and should be properly disposed of and replaced. Depending on how stale or contaminated (with moisture) the fuel is, it may be burned in an automobile or in yard equipment, though it would be wise to mix it well with a much larger supply of fresh gasoline to prevent moving your driveability problems to that engine. But it is better to get the lawn tractor stuck on stale gasoline than it would be to have your boat engine quit in the middle of the bay or lake. For hard-starting engines, is the primer system operating properly. Remember that the prime should only be used for cold starts. A true cold start is really only the first start of the day, but it may be applicable to subsequent starts on cooler days, if the engine sat for more than a few hours and completely cooled off since the last use. Applying the primer to the engine for a hot start may flood the engine, preventing it from starting properly. One method to clear a flood is to crank the engine while at open throttle (allowing the maximum amount of air into the engine to compensate for the excess fuel). But, keep in mind that the throttle should be returned to idle immediately upon engine start-up to prevent damage from over-revving. Fuel delivery and pressure should be checked before delving into the or fuel injection system. Make sure there are no clogs in the fuel line or vacuum leaks that would starve the engine of fuel. Make sure that all other possible problems have been eliminated before touching the carburetor. It is rare that a carburetor will suddenly require an adjustment in order for the engine to run properly. It is much more likely that an improperly stored engine (one stored with untreated fuel in the carburetor) would suffer from one or more clogged carburetor passages sometime after shortly returning to service. Fuel will evaporate over time, leaving behind gummy deposits. If untreated fuel is left in the carburetor for some time (again typically months more than weeks), the varnish left behind by evaporating fuel will likely clog the small passages of the carburetor and cause problems with engine performance. If you suspect this, remove and disassemble the carburetor following procedures under Fuel System. The electronics of the fuel injection system used on some models will monitor the condition of the circuitry. Don't suspect a fuel injection problem unless the CHECK ENGINE indicator of gauge remains illuminated during engine operation. If so, refer to the information on the Fuel Injection system regarding Trouble Codes and fuel injection diagnostics. GENERAL INFORMATION, SAFETY AND TOOLS 1-15 WORK GLOVES See Figure 20 Unless you think scars on your hands are cool, enjoy pain and like wearing bandages, get a good pair of work gloves. Canvas or leather gloves are the best. And yes, we realize that there are some jobs involving small parts that can't be done while wearing work gloves. These jobs are not the ones usually associated with hand injuries. A good pair of rubber gloves (such as those usually associated with dish washing) or vinyl gloves is also a great idea. There are some liquids such as solvents and penetrants that don't belong on your skin. Avoid burns and rashes. Wear these gloves. And lastly, an option. If you're tired of being greasy and dirty all the time, go to the drug store and buy a box of disposable latex gloves like medical professionals wear. You can handle greasy parts, perform small tasks, wash parts, etc. all without getting dirty! These gloves take a surprising amount of abuse without tearing and aren't expensive. Note however, that it has been reported that some people are allergic to the latex or the powder used inside some gloves, so pay attention to what you buy. EYE AND EAR PROTECTION See Figures 21 and 22 Don't begin any job without a good pair of work goggles or impact resistant glasses! When doing any kind of work, it's all too easy to avoid eye injury through this simple precaution. And don't just buy eye protection and leave it on the shelf. Wear it all the time! Things have a habit of breaking, chipping, splashing, spraying, splintering and flying around. And, for some reason, your eye is always in the way! If you wear vision-correcting glasses as a matter of routine, get a pair made with polycarbonate lenses. These lenses are impact resistant and are available at any optometrist. Often overlooked is hearing protection. Engines and power tools are noisy! Loud noises damage your ears. It's as simple as that! The simplest and cheapest form of ear protection is a pair of noise-reducing ear plugs. Cheap insurance for your ears! And, they may even come with their own, cute little carrying case. More substantial, more protection and more money is a good pair of noise reducing earmuffs. They protect from all but the loudest sounds. Hopefully those are sounds that you'll never encounter since they're usually associated with disasters. WORK CLOTHES Everyone has "work clothes." Usually these consist of old jeans and a shirt that has seen better days. That's fine. In addition, a denim work apron is a nice accessory. It's rugged, can hold some spare bolts, and you don't feel bad wiping your hands or tools on it. That's what it's for. When working in cold weather, a one-piece, thermal work outfit is invaluable. Most are rated to below freezing temperatures and are ruggedly constructed. Just look at what local marine mechanics are wearing and that should give you a clue as to what type of clothing is good. There is a whole range of chemicals that you'll find handy for maintenance and repair work. The most common types are: lubricants, penetrants and sealers. Keep these handy. There are also many chemicals that are used for detailing or cleaning. When a particular chemical is not being used, keep it capped, upright and in a safe place. These substances may be flammable, may be irritants or might even be caustic and should always be stored properly, used properly and handled with care. Always read and follow all label directions and be sure to wear hand and eye protection! LUBRICANTS & PENETRANTS See Figure 23 Anti-seize is used to coat certain fasteners prior to installation. This can be especially helpful when two dissimilar metals are in contact (to help prevent corrosion that might lock the fastener in place). This is a good practice on a lot of different fasteners, BUT, NOT on any fastener that might vibrate loose causing a problem. If anti-seize is used on a fastener, it should be checked periodically for proper tightness. Lithium grease, chassis lube, silicone grease or synthetic brake caliper grease can all be used pretty much interchangeably. All can be used for coating rust-prone fasteners and for facilitating the assembly of parts that are a tight fit. Silicone and synthetic greases are the most versatile. Silicone dielectric grease is a non-conductor that is often used to coat the terminals of wiring connectors before fastening them. It may sound odd to coat metal portions of a terminal with something that won't conduct electricity, but here is it how it works. When the connector is fastened the metal-to-metal contact between the terminals will displace the grease (allowing the circuit to be completed). The grease that is displaced will then coat the non-contacted surface and the cavity around the terminals, SEALING them from atmospheric moisture that could cause corrosion. Silicone spray is a good lubricant for hard-to-reach places and parts that shouldn't be up with grease. Penetrating oil may turn out to be one of your best friends when taking something apart that has corroded fasteners. Not only can they make a job easier, they can really help to avoid broken and stripped fasteners. The most familiar penetrating oils are Liquid Wrench@ and A newer penetrant, PB works very well (and has become a mainstay in our shops). These products have hundreds of uses. For your purposes, they are Fig. 20 Three different types of work gloves. The box contains latex gloves Fig. 21 Don't begin major repairs without a pair of goggles for your eyes and earmuffs to protect your hearing Fig. 22 Things have a habit of, splashing, spraying, splintering and flying around during repairs GENERAL INFORMATION, SAFETY AND TOOLS Fig. 23 Anti-seize, penetrating oil, lithium I1Fig. 24 Sealants are essential for preventing grease, electronic cleaner and silicone spray should be a part of your chemical collection Fig. 25 On some engines, RTV is used instead of gasket material to seal components Before disassembling any part, check the fasteners. If any appear rusted, soak them thoroughly with the penetrant and let them stand while you do something else (for particularly rusted or frozen parts you may need to soak them a few days in advance). This simple act can save you hours of tedious work trying to extract a broken bolt or stud. SEALANTS See Figures 24 and 25 Sealants are an indispensable part for certain tasks, especially if you are trying to avoid leaks. The purpose of sealants is to establish a leak-proof bond between or around assembled parts. Most sealers are used in conjunction with gaskets, but some are used instead of conventional gasket material. The most common sealers are the non-hardening types such as No. 2 or its equivalents. These sealers are applied to the mating surfaces of each part to be joined, then a gasket is put in place and the parts are assembled. A sometimes overlooked use for sealants like RTV is on the threads of vibration prone fasteners. One very helpful type of non-hardening sealer is the "high tack" type. This type is a very sticky material that holds the gasket in place while the parts are being assembled. This stuff is really a good idea when you don't have enough hands or fingers to keep everything where it should be. The stand-alone sealers are the Room Temperature Vulcanizing (RTV) silicone aasket makers. On some enaines, this material is used instead of a gasket. those instances, a gasket not be available or, because of the of the matina surfaces, a aasket shouldn't be used. This stuff, when in a gasket, produces the surest'bonds. RTV does have its limitations though. When using this material, you will have a time limit. It starts to set-up within 15 minutes or so, so you have to assemble the parts without delay. In addition, when squeezing the material out of the tube, don't drop any glops into the engine. The stuff will form and set and travel around a cooling passage, possibly blocking it. Also, most types are not fuel-proof. Check the tube for all cautions. CLEANERS + See Figures 26 and 27 There are two basic types of cleaners on the market today: parts cleaners and hand cleaners. The parts cleaners are for the parts; the hand cleaners are for you. They are NOT interchangeable-please resist that urge to use parts cleaner on your hands when they are really bad!! There are many good, non-flammable, biodegradable parts cleaners on the market. These cleaning agents are safe for you, the parts and the environment. Therefore, there is no reason to use flammable, caustic or toxic substances to clean your parts or tools. As far as hand cleaners go; the waterless types are the best. They have always been efficient at cleaning, but they used to all leave a pretty smelly odor. Recently though, most of them have eliminated the odor and added stuff that actually smells good. Fig. 26 Citrus hand cleaners not only work well, but they smell pretty good too. Choose one with pumice for added cleaning power Fig. 27 The use of hand lotion seals your hands and keeps dirt and grease from sticking to your skin Make sure that you pick one that contains lanolin or some other replenishing additive. Cleaners not only remove grease and oil but also skin oil. Most women already know to use a hand lotion when you're all cleaned up. It's okay. Real men DO use hand lotion too! Believe it or not, using hand lotion BEFORE your hands are dirty will actually make them easier to clean when you're finished with a dirty job. Lotion seals your hands, and keeps dirt and grease from sticking to your skin. GENERAL INFORMATION, SAFETY AND TOOLS 1-17 See Figure 28 Tools; this subject could fill a completely separate manual. The first thing you will need to ask yourself, is just how involved do you plan to get. If you are serious about maintenance and repair you will want to gather a quality set of tools to make the job easier, and more enjoyable. BESIDES, TOOLS ARE FUN!!! Almost every do-it-yourselfer loves to accumulate tools. Though most find a way to perform jobs with only a few common tools, they tend to buy more over time, as money ailows. So gathering the tools necessary for maintenance or repair does not have to be an expensive, overnight proposition. When buying tools, the saying "You get what you pay for is absolutely true! Don't go cheap! Any hand tool that you buy should be drop forged chrome vanadium. These two qualities tell you that the tool is strong enough for the job. With any tool, go with a name that you've heard of before, or, that is recommended buy your local professional retailer. Let's go over a list of tools that you'll need. Most of the world uses the metric system. However, many American-built engines and aftermarket accessories use standard fasteners. So, accumulate your tools accordingly. Any good should have a decent set of both and metric measure tools. Don't be confused by terminology. Most advertising refers to "SAE and metric", or "standard and metric." Both are misnomers. The Society of Automotive Engineers (SAE) did not invent the English system of measurement; the English did. The SAE likes metrics just fine. Both English (U.S.) and metric measurements are SAE approved. Also, the current "standard" measurement IS metric. So, if it's not metric, it's measurement. Fig. 28 Socket holders, especially the magnetic type, are handy items to keep tools in order SOCKET SETS See Figures and 35 Socket sets are the most basic hand tools necessary for repair and maintenance work. For our purposes, socket sets come in three drive sizes: 114 in., 318 in. and 112 in. Drive size refers to the size of the drive lug on the ratchet, breaker bar or speed handle. A 318 in. set is probably the most versatile set in any mechanic's toolbox. It allows you to get into tight places that the larger drive ratchets can't and gives you a range of larger sockets that are still strong enough for heavy- duty work. The socket set that you'll need should range in sizes from 114 in. through 1 in. for standard fasteners, and a 6mm through for metric fasteners. You'll need a good 112 in. set since this size drive lug assures that you won't break a ratchet or socket on large or heavy fasteners. Also, torque wrenches with a torque scale high enough for larger fasteners are usually 112 in. drive. Plus, 114 in. drive sets can be very handy in tight places. Though they usually duplicate functions of the 318 in. set, 114 in. drive sets are easier to use for smaller bolts and nuts. As for the sockets themselves, they come in shallow (standard) and deep lengths as well as 6 or 12 point. The 6 and 12 points designation refers to how many sides are in the socket itself. Each has advantages. The 6 point socket is stronaer and less to which would strir, a bolt head or nut. 12 point sockets are less and can operate better in tight places where the ratchet handle can't swing far. Standard length sockets are good for just about all jobs, however, some stud-head bolts, hard-to-reach bolts, nuts on long studs, etc., require the deep sockets. Fig. 29 A 318 inch socket set is probably the most versatile tool in any mechanic's tool box Fig. 31 Ratchets come in all sizes and Fig. 30 A swivel (U-joint) adapter (left), a in. adapter (center) and a 318 in.-to- 114 in. adapter (right) Fig. 32 Shallow sockets (top) are good for most jobs. But, some bolts require deep configurations from rigid to swivel-headed sockets (bottom) 1-18 GENERAL INFORMATION. SAFETY AND TOOLS Most marine manufacturers use recessed hex-head fasteners to retain See Fig. 33 Hex-head fasteners require a socket with a hex shaped driver See Fig. 34 drivers ... See Fig. 35 . . .and tamper resistant drivers are required to remove special fasteners many of the engine parts. These fasteners require a socket with a hex shaped driver or a large sturdy hex key. To help prevent torn knuckles, we would recommend that you stick to the sockets on any tight fastener and leave the hex keys for lighter applications. Hex driver sockets are available individually or in sets just like conventional sockets. More and more, manufacturers are using TorxB head fasteners, which were once known as tamper resistant fasteners (because many people did not have tools with the necessary odd driver shape). Since TorxB fasteners have become commonplace in manv tool boxes, manufacturers designed newer tamper resistant fasteners that are essentially TorxB head bolts that contain a small in the center the driver to contain a small hole to slide over the protrusion. resistant fasteners are often used where the manufacturer would prefer only knowledgeable mechanics or advanced work. Torque Wrenches 4 See Figure 36 In most applications, a torque wrench can be used to ensure proper installation of a fastener. Torque wrenches come in various designs and most stores will carry a variety to suit your needs. A torque wrench should be used any time you have a specific torque value for a fastener. Keep in mind that because there is no worldwide standardization of fasteners, so charts or figure found in each repair section refer to the manufacturer's fasteners. Any general guideline charts that you might come across based on fastener size (they are sometimes included in a repair manual or with torque wrench packaging) should be used with caution. Just keep in mind that if you are using the right tool for the job, you should not have to strain to tighten a fastener. Beam Type 4 See Figures 37 and 38 The beam type torque wrench is one of the most popular styles in use. If used it can be the most accurate also. Fig. 36 Three types of torque wrenches. Top to bottom: a 318 in. drive beam-type that reads in inch a 112 in, drive clicker-type and a 112 in. drive beam-type Fig. 37 Parts of a beam-type torque wrench head that of the flexible beam (shaft) to a scale located near the . . It consists of a pointer attached to the head that runs the length of the flexible beam (shaft) to a scale located near the handle. As the wrench is pulled, the beam bends and the pointer indicates the torque using the scale. Click (Breakaway) Type 4 See Figures 39 and 40 Another toraue wrench desian is the The mechanism'makes the torque easy most use a ratchetina head for ease of bolt installation. To use the wrench it to a torque setting. Once the torque is reached, wrench has a reflex signaling feature that causes a momentary breakaway of the torque wrench body, sending an impulse to the operator's hand. But be careful, as continuing the turn the wrench after the momentary release will increase torque on the fastener beyond the specified setting. GENERAL INFORMATION, SAFETY AND TOOLS 1-19 Fig. 39 A click-typeor breakaway torque wrench-note this one has a pivoting head Fig. 40 Setting the torque on a click-type wrench involves turning the handle until the specificationappears on the dial Fig. 41 Breaker bars are great for loosening Breaker Bars See Figure 41 Breaker bars are long handles with a drive lug. Their main purpose is to provide extra turning force when breaking loose tight bolts or nuts. They come in all drive sizes and lengths. Always take extra precautions and use the proper technique when using a breaker bar (pull on the bar, don't push, to prevent skinned knuckles). WRENCHES See Figures and 46 Basically, there are 3 kinds of fixed wrenches: open end, box end, and combination. Open-end wrenches have 2-jawed openings at each end of the wrench. These wrenches are able to fit onto just about any nut or bolt. They are extremely versatile but have one major drawback. They can slip on a worn or rounded bolt head or nut, causing bleeding knuckles and a useless fastener. Line wrenches are a special type of open-end wrench designed to fit onto more of the fastener than standard open-end wrenches, thus reducing the chance of rounding the corners of the fastener. Box-end wrenches have a circular jaw at each end of the wrench. They come in both 6 and 12 point versions just like sockets and each type has some of the same advantages and disadvantages as sockets. Combination wrenches have the best of both. They have a open end and a box end. These wrenches are probably the most versatile. As for sizes, you'll probably need a range similar to that of the sockets, about in. through 1 in. for standard fasteners, or through for metric fasteners. As for numbers, you'll need 2 of each size, since, in many instances, one wrench holds the nut while the other turns the bolt. On most fasteners, the nut and bolt are the same size so having two wrenches of the same size comes in handy. Although you will typically just need the sizes we specified, there are some exceptions. Occasionally you will find a nut that is larger. For these, you will need to buy ONE expensive wrench or a very large adjustable. Or you can always just convince the spouse that we are talking about SAFETY here and buy a whole (read expensive) large wrench set. One extremely valuable type of wrench is the adjustable wrench. An adjustable wrench has a fixed upper jaw and a moveable lower jaw. The lower jaw is moved by turning a threaded drum. The advantage of an adjustable wrench is its ability to be adjusted to just about any size fastener. The main drawback of an adjustable wrench is the lower jaw's tendency to move slightly under heavy pressure. This can cause the wrench to slip if it is not facing the right way. ... ... ... DECIMAL 1 3/16" 1 5/16" 7/16" 1 9/16" 5 11/16" ......... ... ............ ... ........................... ......... ......... DECIMAL MILLIMETERS 3mm 4mm ... ...... ... ......... ...... .............. ..... ......... ...... 13mm ......... ...... 16mm Fig. 42 Comparisonof measure and metric wrench sizes 13/16" 22mm 15/16" 24mm 1 25mm 1-20 GENERAL INFORMATION, SAFETY AND TOOLS Fig. 43 Always use a back-up wrench to prevent rounding flare nut fittings Fig. 44 Note how the flare wrench sides are extended to grip the fitting tighter and prevent rounding Fig. 45 Several types and sizes of adjustable wrenches Pulling on an adjustable wrench in the proper direction will cause the jaws to lock in place. Adjustable wrenches come in a large range of sizes, measured by the wrench length. PLIERS See Figure 47 Pliers are simply mechanical fingers. They are, more than anything, an extension of your hand. At least 3 pairs of pliers are an absolute standard, needle nose and slip-joint. In addition to standard pliers there are the slip-joint, multi-position pliers such as pliers and locking pliers, such as Vise Slip-joint pliers are extremely valuable in grasping oddly sized parts and fasteners. Just make sure that you don't use them instead of a wrench too often since they can easily round off a bolt head or nut. Locking pliers are usually used for gripping bolts or studs that can't be removed conventionally, You can get locking pliers in square jawed, nosed and pipe-jawed. Locking pliers can rank right up behind duct tape as the handy-man's best friend. SCREWDRIVERS You can't have too many screwdrivers. They come in 2 basic flavors, either standard or Phillips. Standard blades come in various sizes and thickness for all types of slotted fasteners. Phillips screwdrivers come in sizes with number designations from 1 on up, with the lower number designating the smaller size. Screwdrivers can be purchased separately or in sets. HAMMERS See Figure 48 You need a hammer for just any kind of work. You need a ball-peen hammer for most metal work when using drivers and other like tools. A plastic hammer comes in handy for hitting things safely. A soft-faced blow hammer is used for hitting things safely and hard. Hammers are also VERY useful with non air-powered impact drivers. There are a lot of other tools that every will eventually need (though not all for basic maintenance). . include: Funnels , Chisels Punches Files Hacksaw Portable Bench Vise Tap and Die Set Flashlight Magnetic Bolt Retriever Gasket scraper Putty Knife Extractors Hacksaws have just one things off. You may wonder why you'd need one for something as simple as maintenance or repair, but you never know. Among other things, guide studs to ease parts installation can be made from old bolts with their heads cut off. Fig. 46 You may find a nut that requires a particularly large or small wrench (it is usually available at your local tool store Fig. 47 Pliers and cutters come in many shapes and sizes. You should have an assortment on hand Fig. 48 Three types of hammers. Top to bottom: ball peen, rubber dead-blow, and plastic GENERAL INFORMATION, SAFETY AND TOOLS 1-21 Fig. 49 Almost every marine engine around Fig. 50 The Battery is more than Fig. 51 Multimeters, such as this one from today requires at least one special tool to just a battery charger; when left connected it UEI,are an extremely useful tool for perform a certain task keeps battery fully charged troubleshootina electrical problems I I I A tap and die set might be something you've never needed, but you will eventually. It's a good rule, when everything is apart, to clean-up all threads, on bolts, screws or threaded holes. Also, you'll likely run across a situation in which you will encounter stripped threads. The tap and die set will handle that for you. Gasket scrapers are just what you'd think, tools made for scraping old gasket material off of parts. You don't absolutely need one. Old gasket material can be removed with a putty knife or single edge razor blade. However, putty knives may not be sharp enough for some really stubborn gaskets and razor blades have a knack of breaking just when you don't want them to, inevitably slicing the nearest body part! As the old saying goes, "always use the proper tool for the job. If you're going to use a razor to scrape a gasket, be sure to always use a blade holder. Putty knives really do have a use in a repair shop. Just because you remove all the bolts from a component sealed with a gasket doesn't mean it's going to come off. Most of the time, the gasket and sealer will hold it tightly, Lightly driving a putty knife at various points between the two parts will break the seal without damage to the parts. A small 8-10 inches (20-25 centimeters) long - is extremely useful for removing stuck parts. Never use a screwdriver as a Screwdrivers are not meant for prying. Screwdrivers, used for prying, can break, sending the broken shaft flying! extractors are used for removing broken bolts or studs that have broke off flush with the surface of the part. See Figure 49 Almost every engine around today requires at least one special tool to perform a certain task. In most cases, these tools are specially designed to overcome some unique problem or to fit on some oddly sized component. When manufacturers the trouble of a tool, it is usually necessary to to that the job will right. A special tool might be designed to make a job easier, or it might be used to keep you from damaging or breaking a part. Don't worry, MOST maintenance procedures can either be performed without any special tools OR, because the tools must be used for such basic things, they are commonly available for a reasonable price. It is usually just the low production, highly specialized tools (like a super thin 7-point shaped socket capable of 150 ft. Ibs. (203 Nm) of torque that is used only on the crankshaft nut of the limited production what-dya-callit engine) that tend to be outrageously expensive and hard to find. Hopefully, you will probably never need such a tool. Special tools can be as inexpensive and simple as an adjustable strap wrench or as complicated as an ignition tester. A few common specialty tools are listed here, but check with your dealer or with other boaters for help in determining if there are any special tools for YOUR particular engine. There is an added advantage in advice from others, chances are they may have already found the special tool you need, and know how to get it cheaper (or even let you borrow it). BATTERY TESTERS The best way to test a non-sealed battery is using a hydrometer to check the specific gravity of the acid. Luckily, these are usually inexpensive and are available at most parts stores. Just be careful because the larger testers are usually designed for larger batteries and may require more acid than you will be able to draw from the battery cell. Smaller testers (usually a short, squeeze bulb type) will require less acid and should work on most batteries. Electronic testers are available and are often necessary to tell if a sealed battery is usable. Luckily, many parts stores have them on hand and are willing to test your battery for you. BATTERY CHARGERS See Figure 50 If you are a weekend boater and take your boat out every week, then you will most likely want to buy a battery charger to keep your battery fresh. There are many types available, from low amperage trickle chargers to electronically controlled battery maintenance tools that monitor the battery voltage to prevent over or undercharging. This last type is especially useful if you store your boat for any length of time (such as during the severe winter months found in many Northern climates). Even if you use your boat on a regular basis, you will eventually need a battery charger. The charger should be used anytime the boat is going to be in storage for more than a few weeks or so. Never leave the dock or loading ramp without a battery that is fully charged. Also, some batteries are shipped dry and in a partial charged state. Before placing a new battery of this type into service it must be filled and properly charged. Failure to properly charge a battery (which was shipped dry) before it is put into service will prevent it from ever reaching a fully charged state. MULTIMETERS (DVOMS) See Figure 51 Multimeters or Digital Volt Ohmmeter (DVOMs) are an extremely useful tool for troubleshooting electrical problems. They can be purchased in analog or digital form and have a price range to suit any budget. A multimeter is a voltmeter, ammeter and ohmmeter (along with other features) combined into one instrument. It is often used when testing solid state circuits because of its high input impedance (usually 10 or more). A brief description of the multimeter main test functions follows: Voltmeter-the voltmeter is used to measure voltage at any point in a circuit, or to measure the voltage drop across any part of a circuit. Voltmeters usually have various scales and a selector switch to allow the reading of different voltage ranges. The voltmeter has a positive and a negative lead. To avoid the possibility of damage to the meter, whenever possible, connect the negative lead to the negative (-) side of the circuit (to ground or nearest the ground side of the circuit) and connect the positive lead to the positive side of the circuit (to the power source or the nearest power source). Luckily, most quality DVOMs can adjust their own polarity internally and will indicate (without damage) if the leads are reversed. 1-22 GENERAL INFORMATION, SAFETY AND TOOLS Note that the negative voltmeter lead will always be black and that the Vacuum Gauge positive voltmeter will always be some color other than black (usually red). Ohmmeter-the ohmmeter is designed to read resistance (measured in See Figures 53 and 54 ohms) in a circuit or component. Most ohmmeters will have a selector switch which permits the measurement of different ranges of resistance (usually the selector switch allows the multiplication of the meter reading by 10, 100, 1,000 and 10,000). Some ohmmeters are "auto-ranging" which means the meter itself will determine which scale to use. Since the meters are powered bv an internal batterv, the ohmmeter can be used like a self-oowered test light. When the is connected, current from the ohmmeter flows the circuit or component beina tested. Since the ohmmeter's internal and voltage are known values, the amount of current flow through the meter depends on the resistance of the circuit or component being tested. The ohmmeter can also be used to perform a continuity test for suspected open circuits. In using the meter for making continuity checks, do not be concerned with the actual resistance readings. Zero resistance, or any ohm reading, indicates continuity in the circuit. Infinite resistance indicates an opening in the circuit. A high resistance reading where there should be little or none indicates a problem in the circuit. Checks for short circuits are made in the same manner as checks for open circuits, except that the circuit must be isolated from both power and normal ground. Infinite resistance indicates no continuity, while zero resistance indicates a dead short. Never use an ohmmeter to check the resistance of a component or wire while there is voltage applied to the circuit. Ammeter-an ammeter measures the amount of current flowing through a circuit in units called amperes or amps. At normal operating voltage, most circuits have a characteristic amount of amperes, called "current draw" which can be measured using an ammeter. By referring to a specified current draw rating, then measuring the amperes and comparing the two values, one can determine what is happening within the circuit to aid in diagnosis. An open circuit, for example, will not allow any current to flow, so the ammeter reading will be zero. A damaged component or circuit will have an increased current draw, so the reading will be high. The ammeter is always connected in series with the circuit being tested. All of the current that normally flows through the circuit must also flow through the ammeter; if there is any other path for the current to follow, the ammeter reading will not be accurate. The ammeter itself has very little resistance to current flow and, therefore, will not affect the circuit, but, it will measure current draw only when the circuit is closed and electricity is flowing. Excessive current draw can blow fuses and drain the battery, while a reduced current draw can cause engines to run slowly, lights to dim and other components to not operate properly. GAUGES Compression Gauge See Figure 52 An important element in checking the overall condition of your engine is to check compression. This becomes increasingly more important on engines with high hours. Compression gauges are available as screw-in types and hold-in types. The screw-in type is slower to use, but eliminates the possibility of a faulty reading due to pressure escaping by the seal. A compression reading will uncover many problems that can cause rough running. Normally, these are not the sort of problems that can be cured by a tune-up. Eventually, you are going to have to measure something. To do this, you will need at least a few precision tools. MICROMETERS CALIPERS Micrometers and calipers are devices used to make extremely precise measurements. The simple truth is that you really won't have the need for many of these items just for routine maintenance. But, measuring tools, such as an outside caliper can be handy during repairs. And, if you decide to tackle a major overhaul, a micrometer will absolutely be necessary. Should you decide on becoming more involved in boat engine mechanics, such as repair or rebuilding, then these tools will become very important. The success of any rebuild is dependent, to a great extent on the ability to check the size and fit of components as specified by the manufacturer. These measurements are often made in thousandths and thousandths of an inch. Micrometers See Figure 55 A micrometer is an instrument made up of a precisely machined spindle that is rotated in a fixed nut, opening and closing the distance between the end of the spindle and a fixed anvil. When measuring using a micrometer, don't overtighten the tool on the part as either the component or tool may be damaged, and either way, an incorrect reading will result. Most micrometers are equipped with some form of thumbwheel on the spindle that is designed to freewheel over a certain light touch (automatically adjusting the spindle and preventing it from overtightening). Outside micrometers can be used to check the thickness of parts such shims or the outside diameter of components like the crankshaft journals. They are also used during many rebuild and repair procedures to measure the diameter of components such as the pistons. The most common type of micrometer reads in 111000 of an inch. Micrometers that use a vernier scale can estimate to 1110 of an inch. Inside micrometers are used to measure the distance between two parallel surfaces. For example, in engine rebuilding work, the "inside mike" measures cylinder bore wear and taper. Inside mikes are graduated the same way as outside mikes and are read the same way as well. Remember that an inside mike must be absolutely perpendicular to the work being measured. When you measure with an inside mike, rock the mike gently from side to side and tip it back and forth slightly so that you span the widest part of the bore. Just to be on the safe side, take several readings. It takes a certain amount of experience to work any mike with confidence. Metric micrometers are read in the same way as inch micrometers, except that the measurements are in millimeters. Each line on the main scale equals lmm. Each fifth line is stamped 5, 10, 15 and so on. Each line on the thimble scale equals 0.01 mm. It will take a little practice, but if you can read an inch mike, you can read a metric mike. Fig. 52 Cylinder compression test results are extremely valuable indicators of internal engine condition Fig. 53 Vacuum gauges are useful for Fig. 54 You can also use the vacuum gauge troubleshooting including testing some fuel on a hand-operated vacuum pump for tests GENERAL INFORMATION, SAFETY AND TOOLS 1-23 Fig. 55 Outside micrometers measure the Fig. 56 Calipers are the fast and easy way to Fig. 57 Calipers can also be used to measure depth . .. thickness of parts like shims or the diameter make precise measurements of a shaft Fig. 58 . . .and inside diameter measurements, usually to 0.001 inch accuracy Calipers See Figures and 58 Fig. 59 This dial indicator is measuring the end-play of a crankshaft during an engine rebuild Fig. 60 Telescoping gauges are used during engine rebuilding procedures to measure the diameter Inside and outside calipers are useful devices to have if you need to measure something quickly and absolute precise measurement is not necessary. Simply take the reading and then hold the calipers on an accurate steel rule. Calipers, like micrometers, will often contain a thumbwheel to help ensure accurate measurement. INDICATORS See Figure 59 A dial indicator is a gauge that utilizes a dial face and a needle to register measurements. There is a movable contact arm on the dial indicator. When the arms moves, the needle rotates on the dial. Dial indicators are calibrated to show readings in thousandths of an inch and typically, are used to measure end-play and on various shafts and other components. Dial indicators are quite easy to use, although they are relatively expensive. A variety of mounting devices are available so that the indicator can be used in a number of situations. Make certain that the contact arm is always parallel to the movement of the work being measured. TELESCOPING GAUGES See Figure 60 A telescope gauge is really only used during rebuilding procedures (NOT during basic maintenance or routine repairs) to measure the inside of bores. It can take the place of an inside mike for some of these jobs. Simply the gauge in the hole to be measured and lock the plungers after they have contacted the walls. Remove the tool and measure across the plungers with an outside micrometer. DEPTH GAUGES See Figure 61 A depth gauge can be inserted into a bore or other small hole to determine exactly how deep it is. One common use for a depth gauge is measuring the distance the piston sits below the deck of the block at top dead center. Some outside calipers contain a built-in depth gauge so you can save money and buy just one tool. Fig. 61 Depth gauges are used to measure the depth of bore or other small holes GENERAL INFORMATION, SAFETY AND TOOLS See Figures 62 and 63 Although there are a great variety of fasteners found in the modern boat engine, the most commonly used retainer is the threaded fastener (nuts, bolts, screws, studs, etc). Most threaded retainers may be reused, provided that they are not damaged in use or during the repair. Some retainers (such as stretch bolts or torque prevailing nuts) are designed to deform when tightened or in use and should not be reused. Whenever possible, we will note any special retainers which should be replaced during a procedure. But you should always inspect the condition of a retainer when it is removed and you should replace any that show signs of damage. Check all threads for rust or corrosion that can increase the torque necessary to achieve the desired clamp load for which that fastener was originally selected. Additionally, be sure that the driver surface itself (on the fastener) is not compromised from rounding or other damage. In some cases a driver surface may become only partially rounded, allowing the driver to catch in only one direction. In manv of these occurrences, a fastener mav be installed and tightened, but the would not be able to grip and the fastener again. (This could lead to frustration down the line should that component ever need to be disassembled again). Fig. 63 Thread gauges measure the threads-per-inch and the pitch of a bolt or stud's threads If you must replace a fastener, whether due to design or damage, you must always be sure to use the proper replacement. In all cases, a retainer of the same design, material and strength should be used. Markings on the heads of most bolts will help determine the proper strength of the fastener. The same material, thread and pitch must be selected to assure proper installation and safe operation of the engine afterwards. Thread gauges are available to help measure a bolt or stud's thread. Most part or hardware stores keep gauges available to help you select the proper size. In a pinch, you can use another nut or bolt for a thread gauge. If the A Length B Diameter (major diameter) C Threads per inch or mm Thread length E Size of the wrench required F Root diameter (minor diameter) bolt you are replacing is not too badly damaged, you can select a match by finding another bolt that will thread in its place. you find a nut that will thread properly onto the damaged bolt, then use that nut as a gauge to help select the replacement bolt. If however, the bolt you are replacing is so badly damaged (broken or drilled out) that its threads cannot be used as a gauge, you might start by looking for another bolt (from the same assembly or a location) which will thread into the damaged bolt's mounting. If so, the other bolt can be used to select a nut; the nut can then be used to select the replacement bolt. In all cases, be absolutely sure you have selected the proper replacement. Don't be shv, vou can alwavs ask the store clerk for Be aware that when you find a bolt with damaged threads, you may also find the nut or tapped bore into which it was threaded has also been damaged. If this is the case, you may have to drill and tap the hole, replace the nut or otherwise repair the threads. Never try to force a replacement bolt to fit into the damaged threads. Torque is defined as the measurement of resistance to turning or rotating. It tends to twist a body about an axis of rotation. A common example of this would be tightening a threaded retainer such as a nut, bolt or screw. Measuring torque is one of the most common ways to help assure that a threaded retainer has been properly fastened. When tightening a threaded fastener, torque is applied in three distinct areas, the head, the bearing surface and the clamp load. About 50 percent of the measured torque is used in overcoming bearing friction. This is the friction between the bearing surface of the bolt head, screw head or nut face and the base material or washer (the surface on which the fastener is rotating). Approximately 40 percent of the applied torque is used in overcoming thread friction. This leaves only about 10 percent of the applied torque to develop a useful clamp load (the force that holds a joint together). This means that friction can account for as much as 90 percent of the applied torque on a fastener. Specifications are often used to help you determine the condition of various components, or to assist you in their installation. Some of the most common measurements include length (in. or torque (ft. Ibs., inch Ibs. or Nm) and pressure (psi, in. Hg, or mm Hg). In some cases, that value may not be conveniently measured with what is available in your toolbox. Luckily, many of the measuring devices that are available today will have two scales so or Metric measurements may easily be taken. If any of the various measuring tools that are available to you do not contain the same scale as listed in your specifications, use the accompanying conversion factors to determine the proper value. The conversion factor chart is used by taking the given specification and multiplying it by the necessary conversion factor. For instance, looking at the first line, if you have a measurement in inches such as "free-play should be 2 in." but your ruler reads only in millimeters, multiply 2 in. by the conversion factor of 25.4 to get the metric equivalent of Likewise, if a specification was given only in a Metric measurement, for example in Newton Meters (Nm), then look at the center column first. If the measurement is 100 multiply it by the conversion factor of 0.738 to get 73.8 ft. Ibs. GENERAL INFORMATION, SAFETY AND TOOLS 1-25 CONVERSION FACTORS LENGTH-DISTANCE = Inches Feet (ft.) Inches (in.) = Millimeters (mm) = Feet Miles = Meters (m) = Miles = Kilometers (km) VOLUME = in3 IMP Pints (IMP pt.) = Cubic Centimeters Cubic Inches = IMP pt. IMP Quarts (IMP qt.) = Liters (L) = IMP qt. IMP Gallons (IMP gal.) = Liters (L) = IMP gal. IMP Quarts (IMP qt.) = Liters (L) = IMP qt. IMP Gallons (IMP gal.) = US Quarts (US qt.) = IMP gal. Ounces = US Gallons (US gal.) = Ounces US Pints (US pt ) = Milliliters = Pints US Quarts (US qt.) = Liters (L) = Quarts US Gallons (US gal.) = Liters (L) = Gallons = Liters (L) MASS-WEIGHT = Ounces Pounds (lb.) Ounces (oz.) = Grams (g) = Pounds = Kilograms (kg) PRESSURE = psi Inches of Mercury (Hg) = Kilopascals Pounds Per Sq. In. (psi) = Hg Inches of Mercury (Hg) = psi = Hg Inches of Water = Kilopascals = = Inches of Mercury = = psiInches of Water = Inches of Water = Kilopascals TORQUE = in-lb Pounds-Force Feet (ft-lb) Pounds-Force Inches (in-lb) = Newton Meters (N = ft-lb = Newton Meters VELOCITY = MPHMiles Per Hour (MPH) = Kilometers Per Hour (KPH) x POWER Horsepower (Hp) = Kilowatts x 1.34 = Horsepower FUEL CONSUMPTION* Miles Per Gallon IMP (MPG) x = Kilometers Per Liter Kilometers Per Liter x 2.352 = IMP MPG Miles Per Gallon US (MPG) x = Kilometers Per Liter Kilometers Per Liter x 2.352 = US MPG *It is common to covert from miles per gallon (mpg) to kilometers km), where mpg (IMP) x km = 282 and mpg (US) x km = 235. TEMPERATURE Degree Fahrenheit ("F) = ("C x 1.8) 32 Degree Celsius ("C) = ("F -32) x .56 1-26 GENERALINFORMATION, SAFETYANDTOOLS Metric Bolts Relative Strength Marking 4.6, 4.8 8.8 Bolt Markings Usage Frequent Infrequent Bolt Size Maximum Torque Maximum Torque Thread Size x Pitch Ft-Lb Nm Ft-Lb Nm SAE Bolts SAE Grade Number 5 Bolt Markings Manufacturers' marks may vary-number of lines always two less than the grade number. Usage Frequent Frequent lnfrequent Bolt Size Maximum Maximum Maximum Torque Torque Torque Ft-Lb kgm Nm Ft-Lb Ft-Lb Nm 5 0.7 6.8 8 1.1 10.8 10 1.4 13.5 -28 6 0.8 8.1 10 1.4 13.6 2-2 ENGINE AND DRIVE MAINTENANCE M = Mechanical Engine Size in Litres I PRAMH I I ,Engine Size in Cubic Inches E = Either R = Right Hand L = Left Hand We estimate that 75% of engine repair work can be directly or indirectly attributed to lack of proper care for the engine. This is especially true of care during the off-season period. There is no way on this green earth for a mechanical engine to be left sitting idle for an extended period of time, say for six months, and then be ready for instant satisfactory service. Imagine, if you will, leaving your car or truck for six months, and then expecting to turn the key, having it roar to life, and being able to drive off in the same manner as a daily occurrence. Therefore it is critical for an engine to either be run (at least once a month), preferably, in the water properly maintained between uses or for it to be for storaae and serviced aaain immediatelv before the start season. Only through a regular maintenance program can the owner expect to receive lona life and satisfactorv at minimum cost. Many if an engine is performing properly, the owner will "nurse" it through the season with good intentions of working on the unit once it is no longer being used. As with many New Year's resolutions, the good intentions are not completed and the engine may lie for many months before the work is begun or the unit is taken to the marine shop for repair. Imagine, if you will, the cause of the problem being a blown head gasket. And let us assume water has found its way into a cylinder. This water, allowed to remain over a long period of time, will do considerably more damage than it would have if the unit had been disassembled and the repair work performed immediately. Therefore, if an is not functioning properly, do not stow it away with promises to at it when you get because the work and exoense will onlv aet worse. the lonaer corrective action is postponed. In the example of blown head a relatively simple and inexpensive repair job could very well develop into major overhaul and rebuild work. OK, perhaps no one thing that do as boaters will protect us from risks involved with enjoying the wind and the water on a powerboat. But, each time we perform maintenance on our boat or motor, we increase the likelihood that we will find a potential hazard before it becomes a problem. Each time we inspect our boat and motor, we decrease the possibility that it could leave us stranded on the water. In this way, performing boat and engine service is one of the most important ways that we, as boaters, can help protect ourselves, our boats, and the friends and family that we bring aboard. An engine specifications decal can generally be found on top of the flame arrestor, on the side of the thermostat housing, or on the of the rocker arm cover, usually near the line (most models); all pertinent serial number information can be found here-engine and drive designations, serial numbers and model numbers. Unfortunately this decal is not always legible on older engines and it can be quite difficult to find, so please refer to the following procedures for each individual unit's serial number location. Serial numbers tags are frequently difficult to see when the engine is installed in the boat; a mirror can be a handy way to read all the numbers. ENGINE See Figures, and 7 The engine serial numbers are the manufacturer's key to engine changes. These alpha-numeric codes identify the year of manufacture, the horsepower rating and various modelloption differences. If any correspondence or parts are required, the engine serial number must be used for proper identification. Remember that the serial number establishes the year in which the engine was produced, which is often not the year of first installation. The engine specifications decal contains information such as the model number or code, the serial number (a unique sequential identifier given ONLY to that one engine) as well as other useful information. An engine specifications decal can generally be found on top of the flame arrestor, on the side of the thermostat housing (early engines), or on the inner side of the rocker arm cover, usually near the line (port side on most models) all pertinent serial number information can be found here-engine and drive designations, serial numbers and model B = Second Model Released, etc. I 1 Decoding the engine model number is easy ENGINE AND DRIVE MAINTENANCE 2-3 numbers. Unfortunately this decal is not always legible on older boats and it's also quite difficult to find, so please refer to the following procedures for each individuals unit's serial number location. Serial numbers tags are frequently difficult to see when the engine is installed in the boat; a mirror can be a handy way to read all the numbers. The engine seriallmodel number is sometimes also stamped on the port rear side of the engine where it attaches to the bell housing; although on most later models it may instead be a metal plate attached in the same location. If your engine has a stamped number it will simply be the serial number; if you have a plate (and you should), it will always show a Model number and then the actual Serial number. Additionally, most models will also have this plate or sticker on the transom bracket. The first two characters identify the engine size in liters (L); 30 represents the 43 represents the 50 represents the and so forth. Please note though, that there were a few King Cobra engines that listed the engine size in cubic inches; the 1989 460 for example used the first three characters and showed 460 rather than the 75 that it would normally show. The third character identifies the fuel delivery system; 2 designates a 2 bbl carburetor, 4 is a 4 bbl carburetor, and F is a fuel injected engine. Remember those King Cobras we just discussed? If the engine designation is in cubic inches rather than liters, the third character will not be used to designate the type of fuel delivery. The fourth character designates a major engine or horsepower change-it doesn't let you know what the change was, just that there was some sort of change. A means it is the first model released, B would be the second, and so forth The fifth character designates what type of steering system was used; M would be manual steering and P would be power steering. Now here's where it gets interesting; on engines and 1994-98 engines, the sixth, seventh and eighth characters designate the model year. The sixth and seventh actually show the model year, while the eighth is a random model year version code. KWB and WXS represent 1986; and ARJ, ARF, FTC, SRC or SRY show 1987. MDA is 1994, HUB is 1995, NCA is LKD is 1997 and BYC is 1998. On engines, the sixth character designates the direction of propeller rotation. is right hand, L is left hand and E is either. Also on 1988-93 engines, the seventh, eighth and ninth characters designate the model year. The seventh and eighth actually show the model year, while the nineth is a random model year version code. GDE or GDP is 1988, MED or MEF is 1989, PWC, PWR or PWS is 1990, RGD or RGF is 1991, AMH or AMK is 1992 and JVB or JVN is 1993. Any remaining characters are proprietary. So in example, a Model number on the ID plate that reads would designate a 1987 engine with a 4 bbl carburetor and manual steering, first model released. A number reading designate a 1993 engine with fuel injection, power steering and a right hand propeller, first release; get the picture? STERN DRIVE Figures 8 and 9 The stern drive seriallmodel number plate can be found on the center port side of the unit, just under and beneath the cylinder. Both the serial number and the gear ratio should be on the tag. Make sure you don't confuse the two! You may also find the model number included on the transom assembly tag. TRANSOM ASSEMBLY See Figure 9 The transom assembly serial number can be found on the upper starboard end of the unit. In a marine engine compartment, the minimal amount of dust and dirt in the air mean that a marine air filter requires less maintenance than its counterpart in the automotive world. However, the maintenance of a marine air filter is equally important. Fig. 4 Engine serial number sticker-V6 and Fig. 2 Engine serial number Fig. 3 Engine serial number V8 engines engines and engine similar) engines Fig. 6 On many early engines, the sticker is found on the thermostat housing Fig. 5 The engine serial number sticker on Fig. 7 You should also be able to find a plate injected Ford motors can be found on the on the transom bracket I I Thick Film module bracket enaines 2-4 ENGINE AND DRIVE MAINTENANCE The marine filter prevents dirt from entering the engine. This lessens consumption and extends the engine's life. The air filter on some engines is also used as an intake silencer to quiet the intake air sound as it rushes into the cylinder head from the intake ports. Over time, the air filter element will become clogged with dirt and oil, decreasing the amount of air entering the engine and lowering engine output. If an excessive amount of oil is clogging the filter, this could be an indication of worn cylinders or piston ring failure causing high pressure in the crankcase. The maintenance interval for flame arrestor cleaning is at the end of the first boating season, and then every 100 hours of engine operation or once a year, whichever comes first on 1986-90 engines. On 1991-98 engines, the interval is decreased to every 50 hours of engine operation or once a season, whichever comes first. REMOVAL INSTALLATION All Models Or TBI See Figures 12, 13 and 14 Remove or open the engine compartment cover. 2. Many models utilize a plastic cover over the flame arrestor-if so equipped, remove the retaining nut and lift off the cover. . 3. Tag and disconnect crankcase ventilation hose and bracket from the arrestor and the rocker arm cover. TBI models and later carbureted models will have two hoses and brackets. 2. Remove the nut and washer securing the flame arrestor cover to the carburetor. 3. Lift off the flame arrestor. Unscrew the stud if necessarv. Early and engine utilize a gasket between the arrestor and the carburetor-remove this gasket and discard it. 4. On TBI models, lift the injector baffle off of the stud. To install: 5. Clean the arrestor in solvent and dry with compressed air if possible; otherwise make sure that it dries completely by air. Clean the and then inspect them for cracks or deterioration. Replace if necessary. 6. Install the injector baffle if removed. 7. If you remove the stud, thread it into the carburetor (or throttle body) and tighten it to 65-80 inch Ibs. (7.3-9 Nm). 8. Install a new gasket onto the carburetor on engines if equipped. 9. Position the arrestor over the stud and reconnect the ventilation and 10. Install the washer and nut, tightening it to 30-40 inch Nm) on carbureted models; or 25-35 inch Ibs. Nm) on TBI models. 11. Install the flame arrestor cover (if equipped) and tighten the nut inch Ibs. (3.4-4 Nm) on carbureted models; or 25-35 inch Ibs. (2.8-4 Nm) on TBI models. 12. Close the engine compartment. Ford Engines With MFI + See Figures and 17 Remove or open the engine compartment cover. 2. Remove the four screws securing the plastic flame arrestor cover to the engine and lift off the cover. Set it aside where you won't step on they break easy and they're expensive! 3. Remove the two bolts and washers securing the flame arrestor to the throttle body. 8 Stern drive unit location Fig. 9 Transom assembly serial number tag Fig. 10-Many models will have a decorative cover over the arrestor cover... retaining nut and remove the breather Notice that not all models have a bracket for the hose--this late model has the connection built-in... Make sure you secure the lower bracket while removing the bolts as it will fall free when the bolts are removed. ENGINE AND DRIVE MAINTENANCE Fig. 13 ...and then lift off the arrestor I Fig. 14 Here's a good shot of the breather hose 4. Cut the plastic tie strap securing the breather hose to the oil filler fitting and wiggle the hose off the nipple. 5. Lift off the flame arrestor. To install: 6. Clean the arrestor in solvent and dry with compressed air if possible; otherwise make sure that it dries completely by air. 7. Check the rubber gasket around the throttle body throat for any cracks, tears or other obvious signs of deterioration. Replace if necessary and make sure that it seats properly. The little nipple must be facing downward. We would replace it whether it needs it or insurance; but you make the call. 8. Position the arrestor over the throttle body throat and move the lower bracket into position so the nipple in the gasket fits into the hole on the bracket. Install the bolts finger-tight. When tightening the flame arrestor, you must have pressure on it while tightening the mounting bolts in order to ensure against any air leaks. 9. Have an assistant press the arrestor in, and against, the throttle body while you tighten the two mounting bolts to 24-48 inch Ibs. (2.75-4.8 Nm). 10. the breather hose back into position on the filler nipple and . . secure it a new plastic tie. 11. Install the plastic cover and tighten the four screws securely. Make sure don't tighten them too much or crack the cover. Close engine compartment. Fig. 15 Remove the 4 screws and lift off the plastic cover Fig. 16 Remove the 2 bolts and lift off the flame arrestor GM Engines With MFI Except 1998 Engines See Figures and 20 Remove or open the engine compartment cover. 2. Carefully wiggle the crankcase ventilation hoses off of their necks on the sides of the arrestor. 3. Remove the nut securing the flame arrestor to the throttle body. 4. Lift off the flame arrestor. Take note of the positioning of the arrestor prior to removal. Many models use a baffle to ensure correct air distribution and must be installed in the same position that they were in when removed. 5. Remove the rubber gasket from the lip on the arrestor. To install: 6. Clean the arrestor in solvent and dry with compressed air if possible; otherwise make sure that it dries completely by air. 7. Check the rubber gasket for any cracks, tears or other obvious signs of deterioration. Replace if necessary and make sure that it seats properly. We would replace it whether it needs it or not-its cheap insurance; but you make the call. 8. Position the arrestor, install the retaining nut and washer and tighten securely but not so tightly as to dimple the cover. 9. Check the breather hose ends for cracks or deterioration and then slide then back into position. 10. Close the engine compartment. 2-6 ENGINE AND DRIVE MAINTENANCE Fig. 17 Make sure the nipple on the gasket in positioned correctly Fig. 19 ...and then make sure it is positioned correctly before reinstalling Fig. 18 Remove the gasket before cleaning the arrestor ... Fig. 20 Tighten the mounting bolt before installing the hoses A fuel filter is designed to keep particles of dirt and debris from entering the carburetors or the fuel injection system and clogging the tiny internal passages of either. A small speck of dirt or sand can drastically affect the ability of the fuel system to deliver the proper amount of air and to the engine. If a filter becomes clogged, the flow of gasoline will be impeded. This could cause lean fuel mixtures, hesitation and stumbling and idle problems in carburetors. Although a clogged fuel passage in a fuel injected engine could also cause lean symptoms and idle problems, dirt can also prevent a fuel injector from closing properly. A fuel injector that is stuck partially open by debris would likely cause the engine to run rich due to the unregulated fuel constantly spraying from the pressurized injector. Regular cleaning or replacement of the fuel filter (depending on the type or types used) will decrease the risk of blocking the flow of fuel to the engine, which could leave you stranded on the water. It will also decrease the risk of damage to the small passages of a carburetor or fuel injector that could require more extensive and expensive replacement. Keep in mind that fuel filters are usually pretty inexpensive (at lease when compared to a tow) and replacement is a simple task. Service your fuel filter on a regular basis to avoid fuel delivery problems. All filters should be replaced no less than once a season or every 50 hours of operation, although halving this interval is cheap insurance! The type of fuel filter used on your engine will vary with the year and model. Because of the number of possible variations it is impossible to accurately give instructions based on model. Instead, we will provide 1998 Engines With MFI See Figures 21 and 22 Remove or open the engine compartment cover. 2. Remove the nuts (one or two, depending on from the plastic cover and lift off the cover. Set it aside where you won't step on it-they break easy and they're expensive! 3. Tag and disconnect the MAP sensor harness connector on the 8.1 L and move it aside. Press inward on the grey plastic lip while carefully pulling down on the lower half of the connector. 4. Back off the adjusting screw on the arrestor clamp until the clamp is loose. 5. Lift off the flame arrestor. Take note of the positioning of the arrestor prior to removal. Many models use a baffle to ensure correct air distribution and must be installed in the same position that they were in when removed. To install: 6. Clean the arrestor in solvent and dry with compressed air if possible; otherwise make sure that it dries completely by air. 7. Position the arrestor, install the retaining clamp and tighten the adjusting screw securely. 8. Reconnect the MAP sensor on the 8.1 L. 9. Install the plastic cover and tighten the securely 10. Close the engine compartment. ENGINE AND DRIVE MAINTENANCE 2-7 instructions for the different types of filters the manufacturer used on various families of motors or systems with which they are equipped. To determine what are utilized by your engine, trace the fuel line from the tank to the fuel pump and then from the pump to the carburetors or throttle body. As a general rule of thumb, the majority of engines covered here utilize a canister-type in-line water separating filter. Most and engines have the filter incorporated into the fuel pump; but may also have an in-line water separating filter. Additionally, most carbureted engines will further utilize a small in the carburetor. As mentioned previously, most new engines have a factory-installed water separating fuel filter. This type filter is also available as an accessory fcr all other engines and should be installed at the earliest possible convenience. Such a kit is not expensive, and contains instructions for correct installation. A water separating filter, as its name suggests, removes water and other fuel system contaminants before they reach the carburetor and helps minimize potential problems. The presence of water in the fuel will alter the proportion of mixture to the "lean" side, resulting in a higher operating temperature and possible damage to pistons, if not corrected. The filter consists of a mounting plate and disposable canister filter (much like an oil filter). The filter is installed between the fuel tank and the fuel REMOVAL INSTALLATION Observe all applicable safety precautions when working around fuel. Whenever servicing the fuel system, always work in a well-ventilated area. Do not allow fuel spray or vapors to come in contact with a spark or open flame. Do not smoke while working around gasoline. Keep a dry chemical fire extinguisher near the work area. Always keep fuel in a container saecifically designed for fuel storage; also, always properly seal fuel containers to avoid the Fuel Pump And Engines See Figures 23 and 24 All engines and MOST engines are equipped with this style filter, but not all-1986-90 engines should have the filter canister in the top half of the fuel pump, 1991-94 engines should have no filter in the fuel pump and use a standard canister filter, while 1995-98 . engines should have the filter in the lower half of the fuel pump. Further, any of these engine may also use a standard in-line canister filter, and they all should have a small in-line filter at the carburetor. Fig. 21 A good shot of the arrestor retaining clamp Fig. 22 Removing the flame Engines ail . I Filter, I I I Gasket, Bowl Fig .23 Some engines have the filter in the top half of the fuel pump... Gasket Fuel Pump Canister 24 ...while others have it in the lower half of the pump 2-8 ENGINE AND DRIVE MAINTENANCE Observe all applicable safety precautions when working around fuel. Whenever servicing the fuel system, always work in a well-ventilated area. Do not allow fuel spray or vapors to come in contact with a spark or open flame. Do not smoke while working around gasoline. Keep a dry chemical fire extinguisher near the work area. Always keep fuel in a container specifically designed for fuel storage; also, always properly seal fuel containers to avoid the possibility of fire or explosion. 1. Remove or open the engine compartment hatch. 2. Disconnect the negative battery cable and then remove the flame arrestor. 3. Remove the safety wire from the screw at the bottom (or top) of the 4. Loosen the screw and release the filter bowl bail from the housing. It's not necessary to remove the bail completely, you can usually swing the bail to the side far enough to allow removal of the There will be fuel in the bowl, so have plenty of rags available. 5. Carefully pry the bowl from the pump housing and remove the spring, filter element and gasket. To install: 6. Clean all parts carefully and check for any cracks, deterioration or other damage. 7. Position the spring, new filter and gasket into the bowl. Make sure that the open end faces the pump. 8. Hold the bowl in position on the pump and snap the retaining bail into place. 9. Tighten the screw securely, but not too tight, and then install the safety wire (if equipped). 10. Reconnect the battery cable, install the flame arrestor and start the engine. Check that there are no fuel leaks and then install or close the engine compartment hatch. Carburetor Fuel Filter See Figures 25and 26 Observe all applicable safety precautions when working around fuel. Whenever servicing the fuel system, always work in a well-ventilated area. Do not allow fuel spray or vapors to come in contact with a spark or open flame. Do not smoke while working around gasoline. Keep a dry chemical fire extinguisher near the work area. Always keep fuel in a container specifically designed for fuel storage; also, always properly seal fuel containers to avoid the possibility of fire or explosion. 1. Remove or open the engine compartment cover. 2. Disconnect the negative battery cable. 3. Remove the flame arrestor as detailed in this section. 4. Position an flare wrench on the fuel inlet filter nut at the carburetor. Position another wrench on the fuel line nut. Loosen the fuel line nut while holding the inlet nut with the other wrench and pull out the fuel line. Make sure you plug the line to prevent any fuel from spilling and carefully position it out of the way. 5. Loosen and then carefully remove the inlet nut from the carburetor body. Pull out the (one or two), the filter element and the spring. On models with a non-replaceable filter, the inlet nut will simply have a filter screen attached to its inner end. There will be no small washer, filter element or spring. To install: 6. Although most elements can be cleaned and reused, we recommend replacement with a new one whenever possible. Certain models do not utilize a replaceable filter, instead they will have a filter screen attached to the inner end of the inlet nut which can only be cleaned and reused. 7. On models with a replaceable filter: a. Insert the spring into the carburetor and then slide in the filter element. Be sure that the open end of the filter faces out (toward the inlet nut). b. Position the large gasket over the inlet nut threads and the small one inside the nut. Screw the nut into the carburetor and tighten it securely; but not too tight. 8. On models with a non-replaceable filter: a. Slide the washer over the inlet nut threads. b. Screw the nut into the carburetor and tighten it securely; but not too tight. 9. Clean the threads and position the fuel line nut into the inlet, seat it a few turns with your fingers and then tighten it to 11-13 ft. Ibs. (14.9-17.6 Nm). 10. Install the flame arrestor and connect the battery cable. Start the engine and check for fuel leaks. 11. Install or close the engine compartment. Water Separating Canister Filter See Figures 27and 28 Observe all applicable safety precautions when working around fuel. Whenever servicing the fuel system, always work in a well-ventilated area. Do not allow fuel spray or vapors to come in contact with a spark or open flame. Do not smoke while working around gasoline. Keep a dry chemical fire extinguisher near the work area. Always keep fuel in a container specifically designed for fuel storage; also, always properly seal fuel containers to avoid the possibility of fire or explosion. 1. Remove or open the engine compartment hatch. 2. Disconnect the negative battery cables. 3. Remove the canister filter from the mounting plate by rotating the canister counterclockwise-as viewed from the bottom end of the filter canister. An oil filter strap wrench may be necessary to break the filter free. Keep the filter upright to avoid spilling fuel. Properly dispose of the fuel and fuel saturated canister. Make sure you have plenty of rags handy just in case! The old canister filter cannot be cleaned and used a second time. Never attempt to reuse the filter! To install: 4. Coat the sealing of a NEW canister filter with clean engine oil (there may be two rings so make-sure that the old one comes out and the new one goes in!). 5. Install the filter onto the mounting plate and tighten it securely by hand-approximately 112 of a turn after the gasket makes initial contact with the flange. Never use an oil filter wrench to tighten the canister. 6. Reconnect the battery cables and start the engine. Check that there are no fuel leaks and then close the engine hatch. INSPECTION See Figures and 33 V-belts should be inspected on a regular basis for signs of glazing or cracking. A glazed belt will be perfectly smooth from slippage, while a good belt will have a slight texture of fabric visible. Cracks will usually start at the inner edge of the belt and run outward. All worn or damaged drive belts ENGINE AND DRIVE MAINTENANCE 2-9 lnlet Bracket Element Fig. 27 Typical water separating fuel filter Fig. 26 ...while models with a non-replaceable inlet filter will look like this should be replaced immediately. It is best to replace all drive belts at one time, as a preventive maintenance measure, during this service operation. Inspect the alternator, power steering, sea-water supply pump and water pump V-belts every 50 hours or twice a season (whichever comes first) for evidence of wear such as cracking, fraying, and incorrect tension. New belts should be checked after the first hours of operation. Determine the V-belt tension at a point halfway between the pulleys by pressing on the belt with moderate thumb pressure. The belt should deflect in. on all engines. If the defection is found to be too much or too little, make adjustments as necessary. Always test the tension between the component pulley and the engine circulating pump (water lnlet nut screen Fig. 28 The filter canister is usually mounted at the front of the engine, on either side depending upon the application An alternate method (and actually much more accurate) is to use an OMC tension gauge or an equivalent tension gauge and check that the tension is 44-55 Ibs. (20-25 kg). When replacing belts, we recommend cleaning the inside of the belt pulleys to extend the service life of the belts. Never use automotive belts, marine belts used on your engine are heavy duty and not interchangeable. Fig. 29 An example of a healthy drive belt Fig 30 Deep cracks in this belt will cause Fig. 31 The cover of this belt is worn, flex, building up heat that will eventually lead exposing the critical reinforcing cords to to belt failure excessive wear 2-10 ENGINE AND DRIVE MAINTENANCE Fig. 32 Installing too wide a belt can result in serious belt wear breakage Fig. 33 Check the drive belt tension with your thumb ROUTING DIAGRAMS See Figures 34 thru 40 Power Steering Water Fig. Fig. 34 Drive belt routing-2.31 engines 35 Drive belt routing-1986-93 and Ford engines Fig. 37 Drive belt routing-1987-93 and GM and 1990-95 GM engines Water Alternator \ I Pump Fig. 36 Drive belt routing1994- 96 and Ford engines ENGINE AND DRIVE MAINTENANCE 2-11 Fig. 38 Drive belt routing-1994-98 Pump engines Pump Fig. 39 Drive belt routing-1994-98 and GM engines GM enaines ADJUSTMENT Alternator See Figure 41 Although most alternators can be found on the upper port side of the engine, certain Ford engines will have it located on the lower port side. Remove or open the engine hatch and disconnect the battery cables. 2. Loosen the nut on the lower pivot bolt at the bottom of the alternator. 3. Loosen the bolt on the adiustment bracket behind the assemblv. 4. Carefully insert a in. bar into the space between alternator and a sturdy spot on the engine block, and then pivot the alternator away from the engine. 5. Check that the tension is now within specifications and tighten the bolt and nut while keeping steady pressure on the breaker bar. 6. Recheck the belt tension and connect the cable. 7. Close the engine Fig. 41 A good shot of the adjustment bracket and bolt (upper) and the pivot bolt shown Power Steering Pump SY All Engines Except See Figures 42 and 43 Although on most engines the power steering pump can be found on the lower port side of the engine; engines have it located on the lower starboard side, while Ford engines will have it on the upper port side. Remove or open the engine hatch and disconnect the battery cables. 2. Loosen the power steering pump mounting bolts nuts-usually two, but the engine use four (3 in the front and 1 in the back). 3. Insert a in. breaker bar into the square hole on the mounting bracket and then pivot the pump assembly away from the engine. Never pry against the reservoir or filler neck. 4. Check that the tension is now within specifications and tighten the mounting bolts or nuts while keeping steady pressure on the breaker bar. 5. Recheck the belt tension and connect the battery cable. 6. Close the engine compartment. Fig. 40 Drive belt routing-1987-90 Ford engines 2-12 ENGINE AND DRIVE MAINTENANCE And Engines + See Figure 44 Although on the two GM engines the power steering pump can be found on the lower port side of the engine; engines will have it located on the lower starboard side. 7. Remove or open the engine hatch and disconnect the battery cables. 8. Loosen the pump mounting bracket bolts or nuts. 9. Insert a long screw driver-like breaker bar into the space between the pump and the engine and then pry against the corner of the timing chain cover and the tab on the pump mounting bracket. Never pry against the reservoir or filler neck. 10. Check that the is now within specifications and tighten the bolt closest to the tab. Tighten the remaining bolts while keeping steady pressure on the breaker bar. 11. Recheck the belt tension and connect the batterv cable. 12. Close the engine compartment. Fig. 42 Use the square hole in the bracket to adjust the power steering pump-most GM engine similar I Fig. 43 Use the square hole in the bracket to adjust the power steering Ford engines I Fig. 44 Use the square hole in the bracket to adjust the power steering Ford engines Raw Water Supply Pump See Figure 45 The supply pump is always located on the starboard side of the engine on all applications. Remove or open the engine hatch and disconnect the battery cables. 2. Loosen the mounting bracket bolts. 3. Insert a 112 in. breaker bar (we actually prefer a wooden broom handle) between the pump housing and a sturdy point on the engine and then pivot the pump assembly away from the engine. 4. Check that the tension is now within specifications and tighten the bolts while keeping steady pressure on the breaker bar. Recheck the belt tension and connect the battery cable. 6. Close the engine compartment. REMOVAL INSTALLATION The replacement of the belt on multi-belted mav the removal of the To replace loosen the pivot and mounting bolts of the component which the belt is driving, then, using a wooden lever or equivalent, pry the component inward to relieve the tension on the drive belt; always be careful where you locate the or damage to components may result. Slip the belt off the component pulley, and match the new belt with the old belt for length and width. Fig. 45 A good shot of the adjustment bracket and bolt ENGINE AND DRIVE MAINTENANCE 2-13 These measurements must be equal. It is normal for an old belt to be slightly longer than a new one. After a new belt is installed correctly, properly adjust the tension. When removing more than one belt, be sure to mark them for identification. This will help avoid confusion when replacing the belts. The thermostat is a simple temperature sensitive valve that opens and closes to control cooling water flow through the engrne. In operation, the thermostat hovers somewhere between open and closed. As engine load and temperature increase, the thermostat opens to allow more cooling water into the engine. As temperature and load decrease, the thermostat closes. A sticking thermostat will either allow the temperature to rise well above the normal operating temperature before it opens, or, if stuck in the open position, will never allow the enqine to reach temperature. All thermostats are rated on the at which they open and this ratina should alwavs be stamoed somewhere on the thermostat. usually on area. engines covered here utilize a 160F thermostat except for the engines which use a thermostat rated at 140F.; or models with a closed cooling system which generally use a 170F thermostat. On all engines covered here, the thermostat housing can be found on the front, top of the engine--easily identifiable by the large hoses attached to it. Serious damage may result from operating your engine without a thermostat! Don't even consider this! NEVER use an automotive thermostat in a marine engine. No matter how tempting this may seem, forget it!! REMOVAL & INSTALLATION And Engines-1986-96 See Figures 46 and 47 On all engines covered here, the thermostat housing can be found on the front, top of the identifiable by the large hoses attached to it. Fig. 46 A good shot of the thermostat engines Serious damage may result from operating your engine without a thermostat! Don't even consider this! NEVER use an automotive thermostat in a marine engine. remove the engine hatch cover and disconnect the negative battery cables. 2. Drain all water from the cylinder block and exhaust as detailed in the Cooling System section. 3. Locate the thermostat housing at the front of the engine, loosen the hose clamps and then wiggle all coolant hoses off of the thermostat housing. In many cases you may have to use a small to persuade them off of the fitting-be careful that you don't damage the hose end in the process. Although it is not absolutely necessary to remove the coolant hoses, we feel that it makes the job easier. 4. Loosen and remove the alternator bracket mounting bolt on engines. 5. Remove the 4 mounting bolts (2 on the with their lock washers and then remove the thermostat housina cover. Some models mav have a lifting eye incorporated in the note of its 6. Remove the gasket and be sure to scrape of any remaining material from the two mating surfaces. 7. Lift out the thermostat and discard it. If you are not sure that it is inoperable, perform the testing procedures outlined in this section. Don't forget to remove the cork seal if it doesn't come out with the thermostat. To install: 8. Once again, make sure that any remaining gasket material has been removed from the thermostat housing and cover. 9. Position a NEW cork seal in the housing. 10. Insert a new thermostat (160F) into the housing. The element must be pointing into the housing so that the pointy end of the thermostat is facing upward on the or outward on the Make sure that a new cork seal is positioned over the base of the thermostat. 11. Coat both sides of a new housina aasket with OMC Gasket Sealing compound (or similar) and position it housing so that the holes line up. UPPER I THERMOSTAT SEAL, LOWER THERMOSTAT HOUSING RE Fig. 47 Exploded view of the thermostat and housing-3.01 engines 2-14 ENGINE AND MAINTENANCE Install the upper housing cover and mounting and tighten to 5-7 ft. Ibs. (7-9 Nm) on the On the engine, install the housing and bolts, long bolt in the lower hole, and then tighten to 20-25 ft. Ibs. (27-34 13. Reconnect the hoses and tighten the clamps being careful not to pinch the hose. This is a good time to inspect the hoses! 14. Reattach the alternator mounting bracket, recheck the belt tension adjustment and then tighten the bolt securely. 15. Connect the batteries and then start the engine and check for leaks. On all engines covered here, the thermostat housing be found on the front, top of the identifiable by the large hoses attached to it. -- Serious damage may result from operating your engine without a thermostat! Don't even consider this! NEVER use an automotive thermostat in a marine engine. 1. Open or remove the engine hatch cover and disconnect the negative battery cables. 2. Drain all water from the cylinder block and exhaust as detailed in the Cooling System section. 3. Locate the thermostat housing at the front of the engine, loosen the hose clamps and then wiggle the four coolant hoses off of the thermostat housing. In many cases you may have to use a small to persuade them off of the fitting-be careful that you don't damage the hose end in the process. 4. Tag and disconnect (unscrew the nut) the coolant temperature sender lead from the front of the housing and position it out of the way. 5. Loosen the alternator adjusting bolt. Loosen and remove the alternator bracket mounting bolt and pivot it out of the way. 6. Remove the two mounting bolts with their lock washers and then remove the thermostat housing. 7. Remove the gasket and be sure to scrape of any remaining material from the two mating surfaces. 8. Lift out the thermostat and discard it. If you are not sure that it is inoperable, perform the testing procedures outlined in this section. Don't forget to remove the O-ring if it doesn't come out with the thermostat-it holds the thermostat in place, so it should already be out. To install: 9. Once again, make sure that any remaining gasket material has been removed from the thermostat housing and cylinder head. 10. anew thermostat (160F) into the housing. The element must be facing you and the pointed end should be pointing into the housing. 11. Position a NEW O-ring into the groove in the housing so that it retains the thermostat. 12. Position a new housing gasket onto the cylinder head so that the holes line up. 13. Install the housing and tighten the bolts to 12-16 ft. Ibs. (16-22 Nm). 14. Reattach the alternator mounting bracket and tighten the bolt to 30 ft. Ibs. (35-41 Nm). Adjust the belt tension and then tighten the adjusting bolt. 15. Attach the coolant temperature sender lead to the front of the housing and tighten the nut securely. 16. Reconnect the hoses and tighten the clamps being careful not to pinch the hose. This is a good time to inspect the hoses! 17. Connect the batteries and then start the engine and check for leaks. and V8 Engines See Figures and 52 On all engines covered here, the thermostat housing can be found on the front, top of the engine-easily identifiable by the large hoses attached to it. Serious damage may result from operating your engine without a thermostat! Don't even consider this! NEVER use an automotive thermostat in a marine enaine. 1. Open or remove the engine hatch cover and disconnect the negative battery cables. 2. Drain all water from the cylinder block and exhaust as detailed in the Cooling System section. 3. Locate the thermostat housing at the front of the engine, loosen the hose clamps and then wiggle the four coolant hoses off of the thermostat housing. In many cases you may have to use a small to persuade them off of the fitting-be careful that you don't damage the hose end in the process. I models will have five hoses that need to be removed. 1. Remove the two mounting bolts with their lock washers and then remove the thermostat housing. Some models may have a lifting eye attached to the housing-take note of its positioning before removing it. On certain later models you will also need to unscrew the temperature sender and move it out of the way. 2. Remove the gasket and be sure to scrape off any remaining material from the two mating surfaces. 3. Pry out the O-ring that holds the thermostat in place and then lift out the thermostat and discard it. If vou are not sure that it is inoperable, perform the testing procedures outlined this section. HOSE 48 Exploded view of the thermostat and housing-typical, but models similar ENGINE AND DRIVE Fig. 49 Thermostat housing--4.31 engines (Gi shown) Fig. 51 Thermostat Ford engines Fig. 50 Thermostat engines Fig. 52 Thermostat housing-75L engines To install: 4. Once again, make sure that any remaining gasket material has been removed from the thermostat housing and cylinder head. 5. Insert a new thermostat (160F except which use a 140F) into the housing. The element must be facing you when installed in the housing so that it goes into the engine when installed. 6. Position a NEW O-ring into the groove in the housing so that it retains the thermostat. Make sure the O-ring is fully seated in the groove! 7. Coat both sides of a new housing gasket with OMC Gasket Sealing compound (or similar) and position it onto the manifold so that the holes line 8. Install the housing and lifting eye, then tighten the bolts to 20-25 ft. Ibs. (27-34 Nm). 9. Reconnect the hoses and tighten the clamps being careful not to pinch the hose. This is a good time to inspect the hoses! Always ensure that the water supply hose is attached to the correct nipple. On the side with three hoses (or four) it's the lower one in the middle. 10. Connect the batteries and then start the engine and check for leaks. TESTING See Figures and 56 1. Inspect the thermostat at room temperature. If the thermostat is fully open, it is defective and must be replaced. Hold the thermostat up to the light and check it for leaks. A light leak around the perimeter indicates the thermostat is not closing, and therefore, it must be replaced. 2. Attach a length of thread to the thermostat. Now, suspend the thermostat and a thermometer inside a container filled with water (do not use distilled water or ethylene glycol!). Take care to be sure neither the thermostat or the thermometer touches the container. If either one does touch the container, the test will be unreliable 3. Heat the water until the thermostat just begins to open when this happens confirm that the temperature is the same as the thermostat rating. The thermometer reading must agree with the rating stamped on the thermostat; 157-1 for a 160F thermostat, or 138-142F for the unit. If the unit fails the test, it must be replaced. 4. Continue to heat the water until a temperature of 182F is reached; on engines, it should reach 162F. At this time the thermostat should be completely open to 5/32 in. if not, replace it. 5. Turn the heat off and allow the water to cool to a temperature below the rating. The thermostat should now be completely closed; if not, replace it. 2-16 ENGINE AND DRIVE MAINTENANCE Fig. 53 Examine the perimeter of the Fig. 54 Check the gap here on Fig. 55 Check the opening gap here on thermostat for any visible light engine thermostats and V8 engine thermostats SEAT THERMOMETER HEATING CUP Fig. 57 When checking the compression, always use a quality Cylinder compression test results are extremely valuable indicators of internal engine condition. The best marine mechanics automatically check an engine's compression as the first step in a comprehensive tune-up. A compression test will uncover many mechanical problems that can cause rough running or poor performance. CHECKING COMPRESSION See Figures 57 and 58 SY Make sure that the proper amount and viscosity of engine oil is in the crankcase, then ensure the battery is fully charged. 2. Warm-up the engine to normal operating temperature, then shut the engine OFF. If the boat is out of the water, make sure to install a flush test kit. 3. Remove the flame arrestor and open the choke or throttle fully. 4. Disable the ignition system by doing the following: 1986-89 engines Disconnect the high tension lead running between the ignition coil and the distributor at the distributor. Ground the lead to the engine to prevent any sparking. 1990 engines All Cobra engines except HO: Disconnect the high tension lead running between the ignition coil and the distributor at the distributor. Ground the lead to the engine to prevent any sparking. HO: Tag and disconnect the 14-pin connector at the ignition module, Position it out of the way. All King Cobra engines: Remove the mounting bolt and then disconnect the lead at the ignition module. Position it out of the way. 1991-93 enaines On all engines: tag and disconnect the upper 2-wire connector at the ignition coil and position it out of the way. V6 and carbureted Cobra engines except the 1991 HO: remove both distributor primary wires at the coil. Tape the terminals to avoid grounding. 1991 HO: and disconnect the connector at the ignition module. Position it out the way. carbureted King Cobra engines except the 5.7 LE: tag and disconnect the 14-pin connector at the ignition module. Position it out of the way. 5.7 LE: remove both distributor primary wires at the coil. Tape the terminals to avoid grounding. EFI engines: disconnect the 2-way connector at the ignition coil. 1994-95 engines and engines and EFI engines: tag and disconnect the upper 2-wire connector at the ignition coil and position it out of the way.. and engines: remove both distributor primary wires at the coil. Tape the terminals to avoid grounding engines: tag and disconnect the 14-wire connector at the ignition module. EFI engines except the 7.4 EFI: tag and disconnect the 2-way connector at the ignition coil 1996 engines and engines: tag and disconnect the upper (grey) 2-wire connector at the ignition coil and position it out of the way.. and engines: remove both distributor primary wires at the coil. Tape the terminals to avoid grounding ENGINE AND DRIVE MAINTENANCE 2-17 hole and repeat the compression test. If the compression rises after adding oil, it means that the cylinder's piston rings cylinder bore are damaged or worn. If the pressure remains low, the valves may not be seating properly (a valve job is needed), or the head gasket may be blown near that cylinder. 9. If compression in any two adjacent cylinders is low (with normal compression in the other cylinders), and if the addition of oil doesn't help raise compression, there is leakage past the head gasket. Oil and coolant in the combustion chamber, combined with blue or constant white smoke from the tailpipe, are symptoms of this problem. However, don't be alarmed by the normal white smoke emitted from the tailpipe during engine warm-up during cold weather. There may be evidence of water droplets on the engine oil dipstick oil droplets in the cooling system if a head gasket is blown. The spark plug performs four main functions: It fills a hole in the cylinder head. It acts as a dielectric insulator for the ignition system. It provides spark for the combustion process to occur. It removes heat from the combustion chamber. It is important to remember that spark plugs do not create heat, they help remove it. Anything that prevents a spark plug from removing the proper amount of heat can lead to pre-ignition, detonation, premature spark plug failure and even internal engine damage. In the simplest of terms, the spark plug acts as the thermometer of the engine. Much like a doctor examining a patient, this "thermometer" can be used to effectively diagnose the amount of heat present in each combustion chamber. Spark plugs are valuable tuning tools, when interpreted correctly. They will show symptoms of other problems and can reveal a great deal about the engine's overall condition. By evaluating the appearance of the spark plug's firing tip, visual cues can be seen to accurately determine the engine's overall operating condition, get a feel for ratios and even diagnose driveability problems. As spark plugs grow older, they lose their sharp edges and material from the center and ground electrodes is slowly eroded away. As the gap between these two points grows, the voltage required to bridge this gap increases proportionately. The ignition system must work harder to compensate for this higher voltage requirement and hence there is a greater rate of misfires or incomplete combustion cycles. Each misfire means lost horsepower, reduced fuel economy and higher emissions. Replacing worn out spark plugs with new ones (with sharp new edges) effectively restores the ignition system's efficiency and reduces the percentage of misfires, restoring power, economy and reducing emissions. How long spark plugs last will depend on a variety of factors, including engine compression, fuel used, gap, centeriground electrode material and the conditions in which the engine-is operated. SPARK PLUG HEAT RANGE See Figure 59 Spark plug heat range is the ability of the plug to dissipate heat from the combustion chamber. The longer the insulator (or the farther it extends into the engine), the hotter the plug will operate; the shorter the insulator (the closer the electrode is to the block's cooling passages) the cooler it will operate. Selecting a spark plug with the proper heat range will ensure that the tip will maintain a temperature high enough to prevent fouling, yet be cool enough to prevent pre-ignition. A plug that absorbs little heat and remains too cool will quickly accumulate deposits of oil and carbon since it is not hot enough to burn them off. This leads to plug fouling and consequently to misfiring. A plug that absorbs too much heat will have no deposits but, due to the excessive heat, the electrodes will burn away quickly and might possibly lead to pre-ignition or other ignition problems. Pre-ignition takes place when plug tips get so hot that they glow sufficiently to ignite the mixture before the actual spark occurs. This early ignition will usually cause a pinging during heavy loads and if not corrected will result in severe engine damage. While there are many other things that can cause pre-ignition, selecting the proper heat range spark plug will ensure that the spark plug itself is not a hot-spot source. Fig. 58 a cylinder exhibits unusually low compression, try squirting about a tablespoon of oil into it I and and disconnect the 2-way connector at the ignition coil engines: tag and disconnect the 14-wire connector at the ignition module. 1997-98 engines All except and engines: disconnect the grey connector at the ignition coil, it has purple and grey wires engines: remove both distributor primary wires at the coil. Tape the terminals to avoid grounding Disconnect the 14-wire connector at the ignition module. Tag and disconnect all spark plug wires and then remove the plugs themselves. 2. Install a screw-in type compression gauge into the No. 1 cylinder spark plug hole until the fitting is snug. Please refer to the firing order illustrations for location of the No. cylinder. When fitting the compression gauge adapter to the cylinder head, make sure the bleeder of the gauge (if equipped) is closed. 3. According to the tool manufacturer's instructions, connect a remote starting switch to the starting circuit. 4. With the ignition switch in the OFF position, use the remote starting switch to crank the engine through at least five compression strokes (approximately 5 seconds of cranking) and record the highest reading on the gauge. 5. Repeat the test on each cylinder, cranking the engine approximately the same number of compression strokes times as the first. 6. Compare the highest readings from each cylinder to that of the others. The indicated compression pressures are considered within specifications if the lowest reading cylinder is within 75 percent of the pressure recorded for the highest reading cylinder. For example, if your highest reading cylinder pressure was 150 psi (1034 then 75 percent of that would be 113 psi (779 So the lowest reading cylinder should be no less than 113 psi (779 7. Compression readings that are generally low indicate worn, broken, or sticking piston rings, scored pistons or worn cylinders. If a cylinder exhibits an unusually low compression reading, squirt a tablespoon of clean engine oil into the cylinder through the plug or injector 2-18 ENGINE AND DRIVE MAINTENANCE SPARK PLUG SERVICE New technologies in spark plug and ignition system design have pushed the recommended replacement interval higher and higher. However, this depends on usage and conditions. Spark plugs should only require replacement once a season. The electrode on a new spark plug has a sharp edge but with use, this edge becomes rounded by wear, causing the plug gap to increase. As the gap increases, the plug's voltage requirement also increases. It requires a greater voltage to jump the wider gap and about two to three times as much voltage to fire a plug at high speeds than at idle. Tools needed for spark plug replacement include: a ratchet, short extension, spark plug socket (there are two types; either 13116 inch or 518 inch, depending upon the type of plug), a combination spark plug gauge and gapping tool and a can of anti-seize type compound. THE THE PATH. THE FASTER THE HEAT IS DIS- SIPATED AND THE COOLER HEAVY LOADS. SPEEDS THE LONGER HE PATH. THE SLOWER THE HEAT IS THE HOTTER SHORT STOP-ANDGO SHORT LONG Insulator Heal Transfer Slow Heal LOWER Heat HIGHER Heal Range COLD PLUG HOT Fig. 59 Spark plug heat range REMOVAL INSTALLATION See Figures 60 and 61 When removing spark plugs, work on one at a time. Don't by removing the plug wires all at once, because unless you number them, they may become mixed up. Take a minute before you begin and number the wires with tape. 2. Disconnect the negative battery cable or turn the battery switch OFF. 3. If the engine has been run recently, allow the engine to thoroughly cool. Attempting to remove plugs from a hot cylinder head could cause the plugs to seize and damage the threads in the cylinder head, especially on aluminum heads! 4. Carefully twist the spark plug wire boot to loosen it, then pull the boot using a twisting motion to remove it from the plug. Be sure to pull on the boot and not on the wire, otherwise the connector located inside the boot may become separated from the high-tension wire. A spark plug wire removal tool is recommended as it will make removal easier and help prevent damage to the boot and wire assembly. 5. Using compressed air (and safety glasses), blow debris from the spark plug area to assure that no harmful contaminants are allowed to enter the combustion chamber when the spark plug is removed. If compressed air is not available, use a rag or a brush to clean the area. Compressed air is available from both an air compressor or from compressed air in cans available at photography stores. Remove the spark plugs when the engine is cold, if possible, to prevent damage to the threads. If plug removal is difficult, apply a few drops of penetrating oil to the area around the base of the plug and allow it a few minutes to work. 6. Using a 518 in. spark plug socket that is equipped with a rubber insert to properly hold the plug, turn the spark plug counterclockwise to loosen and remove the spark plug from the bore. Avoid the use of a flexible extension on the socket. Use of a flexible extension may allow a shear force to be applied to the plug. A shear force could break the plug off in the cylinder head, leading to costly and frustrating repairs. In addition, be sure to support the ratchet with your other hand-this will also help prevent the socket from damaging the plug. 7. Evaluate each cylinder's performance by comparing the spark plug condition. Check each spark plug to be sure they are all of the same manufacturer and have the same heat range rating. Inspect the threads in the spark plug opening of the block and clean the threads before installing the plug. 8. When ourchasina new alwavs ask the dealer if there has been a spark change for Many times manufacturers will update the type of spark plug used in an engine to offer better efficiency or performance. 9. Crank the engine through several revolutions to blow out any material that might have become dislodged during cleaning. Always use a new gasket (if applicable), but never use gaskets on taper seat plugs. The gasket must be fully compressed on clean seats to complete the heat transfer process and to provide a gas tight seal in the cylinder. Fig. 60 Grab the plug wire boot and twist while removing it Fig. 61 Removing the spark plug ENGINE AND DRIVE MAINTENANCE 2-19 Fig. 63 A carbon-fouled plug, identified by soft, sooty black deposits, may indicate an improperly tuned engine 10. Inspect the spark plug boot for tears or damage. If a damaged boot is found, the spark plug boot and possible the entire wire will need replacement. 11. Check the spark plug gap prior to installing the plug. Most spark plugs do not come gapped to the proper specification. 12. Apply a thin coating of anti-seize on the thread of the plug. This is extremely important on aluminum head engines. 13. Carefully thread the plug into the bore by hand. If resistance is felt before the plug completely bottomed, back the plug out and begin threading again. Do not use the spark plug socket to thread the plugs. Always carefully thread the plug by hand or using an old plug wire to prevent the possibility of cross-threading and damaging the cylinder head bore. 14. Carefully tighten the spark plug. If the plug you are installing is equipped with a crush washer, tighten the plug until the washer seats, then turn it turn to crush the washer. Whenever possible, spark plugs should be tightened to the factory torque specification: engines All engines-15 ft. (20 Nm) 1989 engines (7-13 Nm) 262,350-22 ft. Ibs. (30 Nm) Ford ft. Ibs. (20-27 Nm) 460 King Cobra-5-10 ft. Ibs. (7-13 Nm) 1990 engines ft. Ibs. (7-13 Nm) GM Cobras-22 ft. Ibs. (30 Nm) GM King Cobras-20 ft. Ibs. (27 Nm) Ford V8-15-20 Ibs. (20-27 Nm) engines GM-20 ft. (27 Nm) Ford-5-10 ft. Ibs. Nm) 15. Apply a small amount of silicone dielectric grease to the end of the spark plug lead or inside the spark plug boot to prevent sticking, then install the boot to the spark plug and push until it clicks into place. The click may be felt or heard. Gently pull back on the boot to assure proper contact. 16. Connect the negative battery cable or turn the battery switch ON. 17. Start the engine and proper operation. Fig. 62 A normally worn spark plug should have light tan or gray deposits on the firing tip (electrode) READING SPARK PLUGS See Figures 62 thru 68 Reading spark plugs can be a valuable tuning aid. By insulator firing nose color, you can determine much about the engine's overall operating condition. In general, a light color tells you that the spark plug is at the optimum temperature and that the engine is in good operating condition. Dark coloring, such as heavy black wet or dry deposits usually indicate a fouling problem. Heavy, dry deposits can indicate an overly rich condition, too cold a heat range spark plug, possible vacuum leak, low compression, overly retarded timing or too large a plug gap. If the deposits are wet, it can be an indication of a breached head gasket, oil control from ring problems or an extremely rich condition, depending on what liquid is present at the firing tip. Look for signs of detonation, such as silver specs, black specs or melting or breakage at the firing tip. Compare your plugs to the illustrations shown to identify the most common plug conditions. Fouled Spark Plugs A spark plug is fouled when the insulator nose at the firing tip becomes coated with a foreign substance, such as fuel, oil or carbon. This coating makes it easier for the voltage to follow along the insulator nose and leach back down into the metal shell, grounding out, rather than bridging the gap normally. Fuel, oil and carbon fouling can all be caused by different things but in any case, once a spark plug is fouled, it will not provide voltage to the firing tip and that cylinder will not fire properly. In many cases, the spark plug cannot be cleaned sufficiently to restore normal operation. It is therefore recommended that fouled plugs be replaced. Signs of fouling or excessive heat must be traced quickly to prevent further deterioration of performance and to prevent possible engine damage. Overheated Spark Plugs When a spark plug tip shows signs of melting or is broken, it usually means that excessive heat detonation was present in that particular combustion chamber or that the spark plug was suffering from thermal shock. Fig. 64 A physically damaged spark plug may be evidence of severe detonation in that cylinder. Watch the cylinder carefully between services, as a continued detonation will not only damage the plug but will most likely damage the engine 2-20 ENGINE AND MAINTENANCE I I Fig. 65 An oil-fouled spark plug indicates an stumbling accompanied by a noticeable lack of power with worn piston the gap. with such extreme gap can cause misfiring and Fig. 66 This spark plug has been left in Fig. 67 A bridged or almost bridged the enaine too lona, as evidenced bv spark identified the build-up I between by excessive carbon or oil build-up on the Since spark plugs do not create heat by themselves, one must use this visual clue to track down the root cause of the problem. In any case, damaged firing tips most often indicate that cylinder pressures or temperatures were too high. Left unresolved, this condition usually results in more serious engine damage. Detonation refers to a type of abnormal combustion that is usually preceded by pre-ignition. It is most often caused by a hot spot formed in the combustion chamber. As air and fuel is drawn into the combustion chamber during the intake stroke, this hot spot will "pre-ignite" the air fuel mixture without any spark from the spark plugs. Detonation Detonation exerts a great deal of downward force on the pistons as they are being forced upward by the mechanical action of the connecting rods. When this occurs, the resulting concussion, shock waves and heat can be severe. Spark plug tips can be broken or melted and other internal engine components such as the pistons or connecting rods themselves can be damaged. Left unresolved, engine damage is almost certain to occur, with the spark plug usually suffering the first signs of damage. When signs of detonation or pre-ignition are observed, they are symptom of another problem. You must determine and correct the situation that caused the hot spot to form in the first place. INSPECTION GAPPING See Figures 69 and 70 A particular spark plug might fit hundreds of engines and although the factory will typically set the gap to a pre-selected setting, this gap may not be the right one for your particular engine. Insufficient spark plug gap can cause pre-ignition, detonation, even engine damage. Too much gap can result in a higher rate of misfires, noticeable loss of power, plug fouling and poor economy. Check the spark plug gap before installation. The ground electrode (the L- shaped one connected to the body of the plug) must be parallel to the center electrode and the specified size wire gauge must pass between the electrodes with a slight drag. Do not use a flat feeler gauge when measuring the gap on a used plug, Fig. 69 Using a wire-type spark plug gapping tool to check the between center and ground electrodes 70 Most spark plug gapping tools have an adjusting tool used o bend the ground electrode. USE IT! This tool greatly reduces the of breaking off the electrode and is much more accurate Fig. 68 Typical spark plug problems showing damage that may indicate engine problems ENGINE AND DRIVE MAINTENANCE Tracking Arc High voltage arcs between a fouling deposit on the insulator tip and spark plug shell. This ignites the mixture at some point along the insulator tip. retarding the ignition timing which causes a power and fuel loss. Wide Gap Spark plug electrodes are worn so that the high voltage charge cannot arc across the electrodes. Improper gapping of electrodes on new or spark plugs could cause a similar condition. Fuel remains unburned and a power loss results. Flashover A damaged spark plug boot. along dirt and moisture. could permit the high voltage charge to short over the insulator to the spark plug shell or the engine. buttress insulator helps prevent high voltage flashover. Bridged Electrodes Fouling between the electrodes "ground out" the high voltage needed to fire the spark plug. The arc between the electrodes does not occur and the fuel air mixture is not ignited. This causes a power loss and exhausting of raw fuel. Fouled Spark Plug Deposits that have formed on the insulator may become conductive and provide a path to the shell. This prevents the high voltage from arcing between the electrodes. A power and fuel loss is the result. Cracked Insulator A crack in the spark plug insulator could cause the high voltage charge to out." Here. the spark does not lump the electrode gap and the fuel air mixture not ignited. This causes a power loss and raw fuel exhausted. 2-22 ENGINE AND DRIVE MAINTENANCE because the reading may be inaccurate. A round wire-type gapping tool is the best way to check the gap. The correct gauge should pass through the electrode gap with a slight drag. If you're in doubt, try a wire that is one size smaller or larger. The smaller gauge should go through easily, while the larger one shouldn't go through at all. Wire gapping tools usually have a bending tool attached. Use this tool to adjust the side electrode until the proper distance is obtained. Never attempt to bend the center electrode. Also, be careful not to bend the side electrode too far or too often as it may weaken and break off within the engine, requiring removal of the cylinder head to retrieve it. TESTING DVOM DERATE Each time you remove the engine cover, visually inspect the spark plug wires for burns, cuts or breaks in the insulation. Check the boots on the coil and at the spark plug end. Replace any wire that is damaged. Once a year, usually when you change your spark plugs, check the resistance of the spark plug wires with an ohmmeter. Wires with excessive resistance will cause misfiring and may make the engine difficult to start. In addition worn wires will allow arcing and misfiring in humid conditions, Remove the spark plug wire from the engine. Test the wires by connecting one lead of an ohmmeter to the coil end of the wire and the other lead to the spark plug end of the wire. Resistance should measure approximately 7000 ohms per foot of wire. If a spark plug wire is found to have excessive (high) resistance, the entire set should be replaced. REMOVAL INSTALLATION When installing a new set of spark plug wires, replace the wires at a time so there will be no confusion. Coat the inside of ihe boots with dielectric grease to prevent sticking. Install the boot firmly over the spark plug until it clicks into place. The click may be felt or heard. Gently pull back on the boot to assure proper contact. Repeat the process for each wire. It is important to route the new spark plug wire the same as the original and install it in a similar manner on the engine. Improper routing of spark plug wires may cause engine performance problems. As the engine must be running while performing this operation we recommend that it is undertaken with the boat in the water. If not, make certain that an engine flushing kit has been installed. ADJUSTMENT Ifyou are unsure of which ignition system your engine has been equipped with, please refer to the lgnition System Applications chart. Breaker Point Ignition Systems DERA TE See Figures and 73 If you are unsure of which ignition system your engine has been equipped with, please refer to the lgnition System Application chart found in the lgnition Systems section. Failure to follow the timing procedure instructions exactly will result in improper timing and cause performance problems at the least and possibly severe engine damage. If the timing is completely off, or if the distributor has been removed and the engine rotated, please refer to the initial timing procedures detailed in the Distributor Installation section. Confirm that the dwell angle is within specifications, adjust if necessary. 2. Connect a suitable timing light to the No. 1 spark plug lead (see Firina Order illustrations for location of the No. 1 Connect the supply lead to the battery as detailed in manufacturer's instructions. 3. Connect a tachometer to the engine as detailed by the manufacturer. Do not use the tachometer on the instrument panel as it will not provide the necessary accuracy. 4. Locate the timing mark scale on the engine's timing chain cover (just above the crankshaft pulleylharmonic balancer) and place a bit of white paint where the proper mark should be (TDC is usually marked with a while each mark or gradation should equal Also, paint a dab on the mark stamped into the pulley (4 cyl.) or harmonic balancer On Ford engines, the scale is actually on the harmonic balancer and there is a small pointer attached to the front cover. Please refer to the Specifications chart for the correct timing figure. You may also be able to check the ignition timing specification on the engine tune-up sticker affixed to the engine. If this figure differs from that which is listed here, ALWAYS go with the figure on the sticker. POINTER Fig. 72 Typical timing mark engine Fig. 71 Typical timing mark tab-GM engine ENGINE AND DRIVE MAINTENANCE 2-23 5. Start the engine and allow it to reach normal operating temperature at idle-the choke valve should be wide open. 6. Check that the idle speed is to specification (as per the Tune-Up Specifications chart) with the engine in gear and then shift it to Neutral. 7. While still idling, point the light at the timing marks. The strobe will make it appear that the mark on the tab and the mark on the pulley stand still in alignment. 8. If the timing requires adjustment, loosen the clamp bolt at the base of the distributor and then carefully rotate the distributor or sensor until the correct marks line up. 9. Tighten the clamp bolt to 20 ft. Ibs. (27 Nm) and check the timing one last time. 10. Turn off the engine. Please refer to the Tune-up Specifications chart for the correct timing figure. You may also be able to check the ignition timing specification on the engine tune-up sticker affixed to the engine. If this figure differs from that which is listed here, ALWAYS go with the figure on the sticker. 11. Turn off the engine. Disconnect the timing light and the tachometer. BID And lgnition Systems See Figures and 73 If you are unsure of which ignition system your engine has been equipped with, please refer to the lgnition System Application chart in the lgnition Systems section. Fig. 73 Always use a timing light to adjust the ignition timing Failure to follow the timing procedure instructions exactly will result in improper timing and cause performance problems at the least and possibly severe engine damage. 1. Connect a suitable timing light to the No. 1 spark plug lead (see firing order illustrations for location of the No. 1 cylinder). Connect the power supply lead to the battery as detailed in the light manufacturer's instructions. 2. Connect a tachometer to the engine as detailed by the manufacturer. Do not use the tachometer on the instrument panel as it will not provide the necessary accuracy. 3. Locate the timing mark scale on the engine's timing chain cover (just above the crankshaft balancer) and place a bit of white paint where the proper mark should be (TDC is usually marked with a while each mark or gradation should equal Also, paint a dab on the mark stamped into the pulley (4 cyl.) or harmonic balancer On Ford engines, the scale is actually on the harmonic balancer and there is a small pointer attached to the front cover. Please refer to the Tune-Up Specifications chart for the correct timing figure. You may also be able to check the ignition timing specification on the engine tune-up sticker affixed to the engine. If this figure differs from that which is listed here, ALWAYS go with the figure on the sticker. 4. Start the engine and allow it to reach normal operating temperature at idle-the choke valve should be wide open. 5. Check that the idle speed is to specification (as per the Tune-Up Specifications chart) with the engine in gear and then shift it to Neutral. Always ensure the air gap between the sensor and the trigger wheel is correct before checking ignition timing. 6. While still idling, point the light at the timing marks. The strobe will make it appear that the mark on the tab and the mark on the pulley stand still in alignment. 7. If the timing requires adjustment, loosen the clamp bolt at the base of the distributor and then carefully rotate the distributor or sensor until the correct marks line up. 8. Tighten the clamp bolt to 20 ft. Ibs. (27 Nm) and check the timing one last time. 9. Restart the engine and recheck the idle speed and mixture. Adjust as necessary. Please refer to the Tune-Up Specifications chart for the correct specifications. You may also be able to check the ignition timing specification on the engine tune-up sticker affixed to the engine. If this figure differs from that which is listed here, ALWAYS go with the figure on the sticker. EST Svstems If you are unsure of which ignition system your engine has been equipped with, please refer to the lgnition System Application chart found in the lgnition Systems section. Engines See Figures and 74 Failure to follow the timing procedure instructions exactly will result in improper timing and cause performance problems at the least and possibly severe engine damage. Connect a suitable timing light to the No. 1 spark plug lead (see firing order illustrations for location of the No. 1 cylinder). Connect the power supply lead to the battery as detailed in the light manufacturer's instructions. 2. Connect a tachometer to the engine as detailed by the manufacturer. Do not use the tachometer on the instrument panel as it will not provide the necessary accuracy. 2-24 ENGINE AND DRIVE MAINTENANCE 3. Locate the timing mark scale on the engine's timing chain cover (just above the crankshaft balancer) and place a bit of white paint where the proper mark should be (TDC is usually marked with a while each mark or gradation should equal 2").Also, paint a dab on the mark stamped into the pulley (4 or harmonic balancer On Ford engines, the scale is actually on the harmonic balancer and there is a small pointer attached to the front cover. Please refer to the Tune-Up Specifications chart for the correct timing figure. You may also be able to check the ignition timing specification on the engine tune-up sticker affixed to the engine. If this figure differs from that which is listed here, ALWAYS go with the figure on the sticker. 4. Before moving forward, you must bypass the electronic spark advance function of the EST system. Disconnect the 4-wire connector on the side of the distributor and install OMC Adaptor across the two white leads. Connect the bare wire to a 12-volt engine power source. Not all models will have a harness connected to the 4-wire connector on the distributor. If there is nothing attached, simply remove the connector cover. 5. Start the engine and allow it to reach normal operating temperature at choke valve should be wide open. 6. Check that the idle speed is to specification (as per the Tune-Up Specifications chart) with the engine in gear and then shift it to Neutral. 7. While still idling, point the light at the timing marks. The strobe will make it appear that the mark on the tab and the mark on the pulley stand still in If the timing requires adjustment, loosen the clamp bolt at the base of the distributor and then carefullv rotate the distributor or sensor until the correct marks line up. 74 Before checking the ignition timing on EST systems, you install the connector harness 9. Tighten the clamp bolt securely and check the timing one last time. Turn off the engine, remove the adapter plug from the distributor and reconnect the 4-wire connector (or install the cap if there was no connector). Restart the engine. With the timing light still connected and the engine running at 1000 check that the timing advanced to BTDC on all 1991-94 engines. Re-adjust as necessary by rotating the distributor. Please refer to the Tune-Up Specifications chart for the correct timing figure. You may also be able to check the ignition timing specification on the engine tune-up sticker affixed to the engine. If this figure differs from that which is listed here, ALWAYS go with the figure on the sticker. 12. Turn off the engine. Disconnect the timing light and the tachometer. Engines See Figures and 75 Although ignition timing is adjustable on these models, it is generally controlled by the EFI electronic control module. In order to adjust the timing, the ECM must be forced to enter into its service mode by using a scan tool. This done, the ECM will stabilize the base timing to allow for adjustment by conventional means of rotating the distributor. The idle speed must be correctly adjusted and within specifications before performing this procedure. Open or remove the engine compartment hatch. 2. Connect a suitable timing light to the No. 1 spark plug lead (see firing order illustrations for location of the No. cylinder). Connect the power supply lead to the battery as detailed in the light manufacturer's instructions. 3. Connect a tachometer to the engine as detailed by the manufacturer. Do not use the tachometer on the instrument panel, as it will not provide the necessary accuracy. 4. Locate the timing mark scale on the engine's timing chain cover (just above the crankshaft balancer) and place a bit of white paint where the proper mark should be (TDC is usually marked with a while each mark or gradation should equal Also, paint a dab on the mark stamped into the pulley (4 or harmonic balancer Please refer to the Tune-Up Specifications chart for the correct timing figure. You may also be able to check the ignition timing specification on the engine tune-up sticker affixed to the engine. If this figure differs from that which is listed here, ALWAYS go with the figure on the sticker. 5. Start the engine and allow it to reach normal operating temperature at idle. Set the idle speed to 6. Turn off the engine, locate the data link connector (DLC) on the main harness (usually at the front of the engine on the upper starboard side) and plug in Marine Diagnostic Trouble Code (MDTC) tool-please refer to the Fuel System section for further details on this. If an MDTC is not available, use a jumper wire and connect it between the whitelblack and black wire terminals on the DLC. Fig. 75 MDTCtool makes setting the timing easy ENGINE AND DRIVE MAINTENANCE 2-25 7. Restart the engine and allow the idle to stabilize. 8. Set the MDTC to the ON position. 9. While still idling, point the light at the timing marks. The strobe will make appear that the mark on the tab and the mark on the stand still in alignment. 10. If the timing requires adjustment, loosen the clamp bolt at the base of the distributor and then carefully rotate the distributor until the correct marks line up. 11. Tighten the clamp bolt securely and then recheck the timing. 12. Disconnect the tool or the jumper wire. 13. Check the timing one last time. If still correct, disconnect the light and tachometer. Spitfire EEM lgnition Systems These engine utilize a timing ring mounted on the crankshaft between the flywheel and the engine coupler which directs the EEM module when to fire a particular cylinder. No ignition timing adjustment is necessary or required. Please refer to the lgnition Systems section for further information on the Spitfire system. Thick Film (TFI-IV) lgnition Systems + See Figures 72 and 73 equip ed with, please refer to If you are unsure of which system your engine has been lgnition System Application chart the lgnition Systems section. Failure to follow the timing procedure instructions exactly will result in improper timing and cause performance problems at the least and severe engine damage. 1. Position the shift lever in Neutral. 2. Connect a suitable variable advance, inductive timing light to the No. 1 spark plug lead (see Firing Order illustrations for location of the No. 1 cylinder). Connect the power supply lead to the battery as detailed in the light manufacturer's instructions. 3. Connect a tachometer to the engine as detailed by the manufacturer. Do not use the tachometer on the instrument panel as it will not provide the necessary accuracy. 4. Locate the timing mark scale on the harmonic balancer and place a bit of white paint where the proper mark should be (TDC is usually marked with a while each mark or gradation should equal to check the timingon the engine tune-up sticker the timin figure. You may also be Please refer to the Tune-up S ecifications chart for the correct this figure differs from that which is listed here, ALWAYS go with the figure on the 5. Start the engine and allow it to reach normal operating temperature at idle. 6. Locate the two-wire SPOUT connector (near the front of the engine) and carefully pull out the shorting bar. 7. While still idling, point the light at the timing marks. The strobe will make it appear that the mark on the tab and the mark on the pulley stand still in alignment. 8. If the timing requires adjustment, loosen the clamp bolt at the base of the distributor and then carefully rotate the distributor until the correct marks line up. 9. Apply Electrical Terminal grease to the SPOUT connector terminals and then reinsert the shorting bar. 10. Check the timing advance to ensure it is advancing beyond the initial setting. 13. the engine and recheck the idle speed and mixture. as necessary. Please refer to the Tune-up Specifications chart for the correct specifications. You may also be able to check the ignition timing specification on the engine tune-up sticker affixed to the engine. If this figure differs from that which is listed here, ALWAYS go with the figure on the sticker. All 1986-89 models and many 1990 models were equipped with a standard breaker points ignition system. There are two ways to check breaker point gap: with a feeler gauge or with a dwell meter. Either way you choose, you are adjusting the amount of time (in degrees of distributor rotation) that the points will remain open. If you adjust the points with a feeler gauge, you are setting the maximum amount the points will open when the rubbing block on the points is on one of the high points of the distributor cam. When you adjust the points with a dwell meter, you are measuring the number of degrees (of distributor cam rotation) that the points will remain closed before they start to open as a high point of the distributor cam approaches the rubbing block of the points. Although using a feeler gauge is reasonably accurate when setting new point sets, this method can be unreliable when checking used points due to the rough surface caused by pitting associated with wear and tear. Adjusting the dwell should always be considered the more accurate method. There are two rules that should always be followed when adjusting or replacing points: Points and condenser are a matched set; NEVER replace one without replacing the other. When you change the point gap or dwell of the engine, you also change the ignition timing. Always adjust the timing after a point or dwell adjustment. Marine distributors have a corrosion-resistant coating applied to the return spring on top of the breaker plate and on the two small springs under the plate NEVER use automotive parts as a replacement! REMOVAL AND INSTALLATION See Figures and 78 1. Remove or open the engine compartment hatch cover. Disconnect the negative battery cable or turn the battery switch to OFF. 2. Loosen the distributor cap retaining screws (two) and carefully lift off the cap. Although it is not necessary remove the spark plug wires from the cap, we recommend that you first tag all the wires just to be safe. 3. Note the position of the rotor and pull the rotor straight up and remove it. Check the rotor carefully for a burned or corroded center contact, cracks or carbon tracks. 4. Loosen the primary terminal nut and then disconnect the lead wire. Do the same for the condenser lead wire. 5. Loosen the condenserlbreaker point mounting screws and then lift them up and off the breaker plate. Clean any dirt or oil left on the plate. 6. Coat the distributor cam with a small amount of distributor Cam Lubricant (NEVER use grease or oil), wipe the new point set clean and position it on the breaker plate. Tighten the mounting screws, leaving the lock screw slightly loose.. 7. Reconnect the lead wires for the condenser and primary. 8. Check that the points are in alignment. If not, carefully bend the stationary arm until they align properly. If you are still not satisfied, get a new set of points. Never adjust alignment on used points. 9. Adjust the point gap as detailed following. Install the rotor in the same position is was removed. Install the cap, connect the battery cables and check for proper operation. 10. Adjust the ignition timing AND DRIVE MAINTENANCE Fig. 76 Pull the rotor straight up to remove it Fig. 77 The condenser is held in place by a Fig. 78 lnstall point set on the breaker screw and clamp plate, then attach the wires ADJUSTMENT-FEELER GAUGE See Figures and 81 Perform the first three steps of the removal procedure above. 2. Connect a remote starter switch as detailed in the manufacturers' instructions. Have a friend bump the engine over until you see that the breaker point rubbing block is resting on the high point of the distributor cam-the points should open to their fullest extent. 3. Insert an feeler gauge between the points-please refer to the Up Specifications chart for correct point gap. The gauge should be snug but not tight. If adjustment is required, loosen the lock screw and insert a screwdriver in to the adjustment slot on the breaker plate; move the point set until a slight drag can be felt on the feeler gauge and then tighten the lock screw. Always check the a final time after the screw as the points sometimes move when tightening the Install the rotor and distributor cap. Connect the battery cables and adjust the ignition timing. LATE PROPER MISALIGNMENT LATERAL ALIGNMENT Fig. 80 New contact points must be aligned by bending the fixture contact support. NEVER bend the breaker lever! ADJUSTMENT-DWELL METER See Figure 82 Perform the first three steps of the removal procedure above. 2. Connect a dwell meter as per the manufacturer's instructions usually the positive lead of the meter to the negative side of the coil and the negative lead of the meter to ground. 3. Connect a remote starter switch as detailed in the manufacturer's instructions and then crank the engine. Observe the dwell reading on the meter, it should be as listed in the Specifications chart. If not in range, loosen the lock screw slightly and then adjust the point opening by means of the adjustment slot. Increasing the point gap lowers the dwell reading, while decreasing the gap raises it. When the reading is within specifications, tighten the lock screw and then recheck the dwell one final time. 4. lnstall the rotor and distributor cap. Connect the battery cables and adjust the ignition timing. Dwell should be checked between idle and 1750 rpm. Any dwell variations of more than idle to 1750 rpm indicate possible wear in the distributor. CONTACT ARM NOT Fig. 81 Check the points for proper alignment after installation ARM CONTACT ARM NOT ENGINE AND DRIVE MAINTENANCE GAP SMALL GAP Fig. 82 Three views of differing point dwell conditions EXCESSIVE DWELL FORMAL DWELL-NORMAL GAP INSUFFICIENT DWELL All models equipped with BID ignition systems require an air gap adjustment between the sensor wheel and the trigger wheel; particularly after the distributor has been removed. It is also a good idea to ensure that the air gap is within specification prior to performing any ignition timing procedures ADJUSTMENT-BID DISTRIBUTORS ONLY See Figure 83 or remove the enaine hatches. 2. the distributor and pull off the rotor as detailed in the Ignition System section. 3. Connect a remote starter switch as detailed in the manufacturer's instructions. 4. Check the sensor coil, trigger wheel and teeth for signs of wear or other obvious damage. Using the remote starter, crank the engine around until a tooth on the wheel aligns with the contact on the coil. 5. Insert a nonmetallic flat-bladed feeler gauge between the sensor and trigger wheel tooth. The gap should be 0.008 in. 6. If not within loosen the small screw on the triaaer coil slightly and move the coil carefully until the gap is within spec. the screw securely-but not too tight-and recheck that the gap has not chanaed. Disconnect the remote starter. 8. Install the rotor and distributor cap. Fig. 83 Checking the distributor air gap ADJUSTMENT All Engines Carburetor See Figures 84 and 85 Locate the idle speed screw on your carburetor and turn it in or out until it is just resting on the idle cam, but is not moving it, The idle screw is threaded into the throttle linkage on the side of the carburetor and has a spring between the screw head and the linkage. Locate the idle mixture screw on the base of the carburetor and turn it in (clockwise) until it just lightly seats itself and then back it out: 1986-89 engines-2 turns 1986-89 and engines-2 112 turns 1988-90 Rochester-2 turns engines-112 turn 1988-93 engines-314 turn 1988-93 HO engines-I turn on starboard screw; 112 turn on port screw 1994 engines-314 turn 1994-98 engines-I turn on starboard screw; 112 turn on port screw 1988-94 engines-518 turn 1995-98 engines-518 turn 1996-97 engines-314 turn 1988-90 engines-I 112 turns 1991-93 engines-I turns 1990-93 HO engines-I turn 1994-96 engines-1 turn 1994 engines-314-1 turn 1997-98 engines-314-1 turn Be careful not to turn the idle mixture screw in past the seated position or you risk damaging the seat or needle. Both the screw tip and the casting seat can be affected. Replace any screws suspected of damage. 3. Ensure that the flame arrestor is in place and is free of debris and obstructions. A clogged filter will greatly impact this adjustment, 4. Connect a tachometer as per the manufacturer's instructions--do not use the tach on your boat! 5. Start the engine and allow it to run at idle until it reaches normal operating temperature. 2-28 ENGINE AND DRIVE MAINTENANCE 1-ldle Speed Screw 2- Cam ldle Mixture Needle Fig. 85 Never tighten the idle mixture screw against its seat; some Fig. 84 The idle speed adjusting screw should rest on the idle cam models have two screws Water must circulate through the lower unit and to the engine anytime the engine is being run. Severe damage could result otherwise. If the boat is not in the water, sure a flushing attachment has been installed properly. 6. You will need to disconnect the throttle cable from the throttle lever before performing the next step because the boat will need to be in gear. 7. With the engine still running and the tach hooked up, move the shift lever into F and turn the mixture in (clockwise), carefully and slowly, until the engine speed JUST begins to drop due to a LEAN condition. Jot down the number of turns. If your carburetor has two screws, and it most likely will, there are two schools of thought here-you can adjust them individually or alternately, We prefer the alternating method; that is, turning each screw in a little at a time, the same amount, until you get the LEAN condition. If you go this route, we suggest turning them alternately no more than 118th turn at a time. 8. Now, back the out (counterclockwise), evenly and alternately, until you achieve the correct idle speed as detailed in the Tune- Up Specifications chart. If the idle begins to drop before you get to the correct speed (due to a condition this time) then back them down slightly until it runs smooth again. 9. Recheck the idle speed and compare it to the recommended speed in the chart. If adjustment is required, now you can use the idle speed stop screw-turn it, gradually and evenly, until the correct idle is achieved. 10. Turn the engine off and reconnect the throttle cable. Disconnect the tachometer. All Engines Carbure TE Locate the idle speed screw on your carburetor and it in or out until it just resting on the idle cam, but is not moving it. The idle screw is threaded into the throttle linkage on the side of the carburetor and has a spring between the screw head and the linkage. 2. Locate the idle mixture screw on the base of the carburetor and turn it in (clockwise) until it just lightly seats itself and then back it out: 1986 engines-3 314 turns 1987-89 engines 314 turns 1987-89 engines 112 turns 1990-91 HO engines-314 turn 1996-97 engines-314 turn 1998 engines-I 118 turns 1990-92 engines-I14 turn 1990-91 LE engines-1 turn 1991-92 engines-112 turn 1997 engines-li2 turn 350 engines-1 turn 1990 engines-1 112 turns engines-718 turn 1990 454 engines-1 turn 1991-97 engines-ti4 turn 1990 460 engines-I 112 turns Be careful not to turn the idle mixture screw in past the seated position or you risk damaging the seat or needle. Both the screw tip and the casting seat can be affected. Replace any screws suspected of damage. 3. Ensure that the flame arrestor is in place and is free of debris and obstructions. A clogged filter will greatly impact this adjustment. 4. Connect a tachometer as per the manufacturer's instructions--do not use the tach on your boat! 5. Start the engine and allow it to run at idle until it reaches normal operating temperature. Water must circulate through the lower unit and to the engine anytime the engine is being run. Severe damage could result otherwise. If the boat is not in the water, make sure a flushing attachment has been installed properly. 6. You will need to disconnect the throttle cable from the throttle lever before performing the next step because the boat will need to be in gear. 7. With the engine still running and the tach hooked up, move the shift lever into F and turn the mixture in (clockwise), carefully and slowly, until the engine speed JUST begins to drop due to a LEAN condition. Jot down the number of turns. If your carburetor has two screws, and it most likely will, there are two schools of thought here--you can adjust them individually or alternately. We prefer the alternating method; that is, turning each screw in a little at a time, the same amount, until you get the LEAN condition. If you go this route, we suggest turning them alternately no more than 118th turn at a time. 8. Now, back the out (counterclockwise), evenly and alternately, until you achieve the correct idle speed as detailed in the Tune- Up Specifications chart. If the idle begins to drop before you get to the correct speed (due to a condition this time) then back them down slightly until it runs smooth again. 9. Recheck the idle speed and compare it to the recommended speed in the chart. If adjustment is required, now you can use the idle speed stop screw-turn it, gradually and evenly, until the correct idle is achieved. 10. Turn the engine off and reconnect the throttle cable. Disconnect the tachometer. ENGINE AND DRIVE MAINTENANCE 2-29 Fuel Injected Engines speed is constantly monitored by the electronic control module (ECM) and controlled by the idle air control valve (IAC). speed and mixture are not adjustable. Please refer to the Fuel System section for further information on the fuel injection system. Many engines are equipped with a positive crankcase ventilation (PCV) circuit that utilizes a PCV valve in the rocker cover in order to ventilate unburned crankcase gases back into the engine via the intake manifold in order that they can be re-burned. The PCV valve should be replaced every boating season or 100 hours of operation. A PCV system that is malfunctioning can cause rough running or idle, and also increased fuel consumption. Do not attempt to disconnect or bypass the system. REMOVAL INSTALLATION See Figure 86 Locate the PCV valve in the cylinder head cover-usually the-port but it could be either. 2. Carefully wiggle it back and forth while pulling upward on the valve itself until it pops out of the cover. 3. Loosen the clamp (if equipped) and disconnect the breather hose from the valve. 4. Reconnect the hose and press the valve back into the cylinder head. PCV valves are not serviceable. If your valve is clogged or otherwise not working properly, it must be replaced with a new one. INSPECTION See Figure 87 Start the engine and allow it to reach normal operating temperature. Pop out the PCV valve as detailed above and cover the opening with your thumb. You should be able to feel significant vacuum; if not replace the valve. With the valve still in your fingers, shake it back and forth a few times; you should be able to hear the inside components moving around-a significant clicking sound. If the valve passes these two tests, it is functioning properly. If it fails either of the tests and there are no leaks in any of the hoses or connections, it will require replacement. PCV valves are not serviceable. If your valve is clogged or otherwise not working properly, it must be replaced with a new one. Used fluids such as engine oil, gear oil, antifreeze and power steering fluid are hazardous waste and must be disposed of properly and responsibly. Before draining any fluids it is always a good idea to check with your local authorities; in many areas there are recycling programs available for easy disposal. Service stations, Parts stores and Marinas also often will accept waste fluids for recycling. Be sure of your local recyclers' policies before draining any fluids, as many will not accept fluids that have been mixed together. All engine covered in this manual are designed to run on unleaded fuel. Never use leaded fuel in your boat's engine. The minimum octane rating of fuel being used for your engine must be at least 86 AKI (outside the US, 90 86 PCV valve Fig. 87 Testing the PCV valve All engines covered in this manual are equipped with hydraulic valve lifters and do not require periodic valve adjustment. Adjustment to zero lash is maintained automatically by the-hydraulic pressure in the lifters. For initial adjustment procedures after cylinder head work or if a problem is expected, please refer to the appropriate Engine Mechanical section. RON), on early models and 89 AKI (93 RON) on all others, but some engines may require higher octane ratings. OMC actually recommends the use of 89 AKI (93 RON) fuel as the ideal-in fact, anything less than this on many and engines will require a change to the ignition timing. Fuel should be selected for the brand and octane that performs best with your engine. Check your owner's manual if in doubt. The use of a fuel too low in octane (a measure of anti-knock quality) will result in spark knock. Newer systems have the capability to adjust the engine's ignition timing to compensate to some extent, but if persistent knocking occurs, it may be necessary to switch to a higher grade of fuel. Continuous or heavy knocking may result in engine damage. ENGINE OIL Nothing affects the performance and durability of an engine more than the engine oil. If inferior oil is used, or if your engine oil is not changed regularly, the risk of piston seizure, piston ring sticking, accelerated wear of the cylinder walls or liners, bearings and other moving components increases significantly. 2-30 ENGINE AND DRIVE MAINTENANCE Maintaining the correct engine oil level is one of the most basic (and essential) form of engine maintenance. Get into the habit of checking your oil on a regular basis; all engines naturally consume small amounts of oil, and if left neglected, can consume enough oil to damage the internal components of the engine. Assuming the oil level is correct because you "checked it the last time" can be a costly mistake. If your engine has not been operated for more than 6 months it should be primed prior to starting. When shutting the engine down, always let the engine idle a few minutes to bring engine temperature down to a normal level. Since the engine is, at least in part, cooled by engine oil, it is necessary to allow the engine oil to stabilize prior to shutdown. Not the temperature to stabilize can damage engine components. Everv container of enaine oil for sale in the should have a label what it meets. Engine oil service classifications are designated by the American Petroleum Institute (API), based on the chemical composition of a given type of oil and testing of samples. The ratings include (normal gasoline engine use) and (commercial, fleet and diesel) applications. Over the years, the "S" rating has been supplemented with various letters, each one representing the latest and greatest rating available at the time of its introduction. During recent years these ratings have changed and most recently (at the time of this manual's publication), the rating is or Each successive rating usually meets all of the standards of the previous alpha designation, but also meets some new criteria, meets higher standards contains newer or different additives. Since oil is so important to the life of your engine, you should obviously NEVER use an oil of questionable quality. Oils that are labeled with modern API ratings, including the "energy conserving" donut symbol, have been proven to meet the API quality standards. Always use the highest grade of oil available. The better quality of the oil, the better it will lubricate the internals of your engine. In addition to meeting the classification of the API, your oil should be of a viscositv suitable for the outside in which vour enaine will be Oil must be thin enough to get between moving parts it must lubricate. Once there, it must be thick enough to separate them with a slippery oil film. If the oil is too thin, it won't separate the parts; if it's too thick, it can't squeeze between them in the first either way, excess friction and wear takes place. To complicate matters, morning starts require a thin oil to reduce engine resistance, while high speed requires a thick oil which can lubricate vital enqine parts at Accordina to the Societv of Automotive Enaineers' viscositv classification system, an with a high number as 40 or SAE 50) will be thicker than one with a lower number (SAE The in indicates that the oil is desirable for use in winter operation, and does not stand for "weight". Through the use of special additives, multiple-viscosity oils are available to combine easy starting at cold temperatures with engine protection at high speeds. For example, a oil is said to have the viscosity of a oil when the engine is cold and that of a 40 oil when the engine is warm. The use of such an oil will decrease engine resistance and improve efficiency. All OMC engines require the use of SAE 30 oil at temperatures above (OC). Engines operating in (-18C) to 32F temperatures ranges should use SAE oil; while anyone operating under F (- 18C) should use SAE 1 OW oil. Although acceptable in a pinch and also in certain weather conditions, multi-viscosity oils such as and are not recommended. OMC suggests any recommendation that you may find on your engine regarding a multi-viscosity oil should be ignored. These references are for automotive use only and not intended for marine applications. Priming Anytime your boat's engine has not been run for more than 6 months it is a good idea to prime the engine prior to starting it. 1. Check that the proper amount of oil is in the crankcase (see the Capacities chart). 2. Remove the spark plugs. 3. With the ignition key in the OFF position, connect a remote starter according to the manufacturer's instructions. 4. Crank the engine for 15 seconds and then allow the starter to cool for 1 minute. Repeat this sequence 2 more times until a total cranking time of 45 seconds has been reached. 5. Remove the remote starter. 6. Install the spark plugs and start the engine. OIL LEVEL CHECK See Figures 88 thru 94 S Y The EPA warns that prolonged contact with used engine oil may cause a number of skin disorders, including cancer! You should make every effort to minimize your exposure to used engine oil. Protective gloves should be worn when changing the oil. Wash your hands and any other exposed skin areas as soon as possible after exposure to used engine oil. Soap and water, or waterless hand cleaner should be used. When checking the oil level, it is best that the boat be level and the oil be at operating temperature. Checking the level immediately after stopping the engine will give a false reading; always wait about 5 minutes before checking. It is normal for an engine to naturally consume oil during the course of operation, particularly during break-in on a new engine. You should not be alarmed if the oil level in your engine drops slightly between inspections. In fact, certain of high performance engines may use up to a quart of oil every 5 hours when operated at full throttle. 1. Also the color of the oil is usually a pitch black color. Smelling the oil is a better indicator of oil condition than the color. If the oil smells burned, it should be replaced immediately. Over-filled crankcases can cause a fluctuation or drop in oil pressure, and, particularly on OMC engines, clattering from the rocker arms. Take great care in checking and filling your engine with oil. Always maintain it between the ADD and FULL or OP RANGE markings on the dipstick. Beware of false readings by checking the level too soon after adding oil. It takes a little while for fresh oil poured into the engine to reach the crankcase. Wait for about 3 minutes and then check the oil level again. Oil level should be checked each day the engine is operated and it is best to check it while in the water. 2. Run the enqine until it reaches normal operating temperature. Shut it off and allow the oiito settle for at least 5 minutes. . . 3. Locate the engine oil dipstick-almost always on either side and toward the front of the engine. 4. Clean the area around the dipstick to prevent dirt from entering the engine. 5. Remove the dipstick and note the color of the oil. Wipe the dipstick clean with a rag. Fig. 88 The oil dipstick on the is on the starboard side. Note the top of the oil withdrawal tube ENGINE AND DRIVE MAINTENANCE 2-31 Fig. 90 The oil dipstick on the 89 The oil dipstick on the is on the starboard side, near he power steering pump the engine 6. Insert the dipstick fully into the tube and remove it again. Hold the dipstick horizontal and read the level on the dipstick. The level should always be at the upper limit. If the oil level is below the upper limit, sufficient oil should be added to restore the proper level of oil in the crankcase. Most dipsticks are marked with ADD and FULL or OP RANGE gradations. 7. See Engine Oil Recommendations for the proper viscosity and type of oil. 8. Oil is added through the filler port cap in the top of the cylinder head cover. Add oil slowly and check the level frequently to prevent overfilling the engine. Ford is on the front starboard side of the engine Fig. 92 The oil dipstick on the is on the front of the engine, near the alternator Fig. 93 The oil dipstick on the is on the port side of the engine, near the front similar) Do not overfill the engine. If the engine is overfilled, the crankshaft will whip the engine oil into a foam causing loss of lubrication and severe engine damage. Since you will be hanging into the engine compartment, gather all the tools and spare parts necessary for the job. Don't forget plenty of rags to clean up any spills, and most importantly, remember a container or plastic milk jug to drain the oil into. 1. Start the engine and run it until it reaches normal operating temperature. Turn the engine off and remove the dipstick the withdrawal tube cap. 2. Connect the evacuation pump hose to the dipstick tube or insert it into the withdrawal tube. Position the other hose, or the outlet at the bottom of the pump in your container. Keep in mind that the fast flowing oil, which will spill out of the pump hose, will flow with enough force that it could miss the container and end up all over the deck or in the bilge. Position the container accordingly and be ready to move it if necessary. Some models are equipped with a quick drain oil hose attachment; be sure to pull the tether through the bilge drain before removing the drain plug from the hose. Use caution around the hot oil; when at operating temperature, it is hot enough to cause a severe burn. Fig. 94 The oil dipstick on the is on the port side of the engine, near the front similar) OIL FILTER CHANGE See Figures 95 thru 102 The EPA warns that prolonged contact with used engine oil may cause a number of skin disorders, including cancer! You should make every effort to minimize your exposure to used engine oil. Protective gloves should be worn when changing the oil. Wash your hands and any other exposed skin areas as soon as possible after exposure to used engine oil. Soap and water, or waterless hand cleaner should be used. A few precautions can make the messy job of oil and filter maintenance much easier. By placing oil absorbent pads, available at industrial supply stores, into the area below the engine, you can prevent oil spillage from reaching the bilge. It is a good idea to warm the engine oil first so it will flow better; and the contaminates in the bottom of the pan suspended in the oil. This is accomplished by starting the engine and allowing it to reach normal operating temperature. Changing engine oil is sometimes complicated by the location of the drain plug. Most boats equipped with inboard engines use an evacuation pump to remove the used engine oil through the dipstick tube. If you don't have a mounted oil suction pump in your engine compartment, you may want to consider installing one. This pump sucks waste oil out through either the dipstick tube or a connection on the oil drain plug and is available from your OMC dealer or from any number of aftermarket sources. They come in a variety of configurations: motorized, hand-pumped or attachments for an ordinary household drill. The maintenance interval for oil and filter change is every 100 hours of engine operation or. annually, whichever comes first. This interval should be strictly kept; in fact we recommend cutting the interval in half! 3. Allow the oil to drain until nothing but a few drops come out of the pump. It should be noted that depending on the angle of the engine, some oil may be left in the crankcase. This is normal and should not cause the engine harm. 4. Remove the evacuation pump and reinsert the dipstick or withdrawal tube cap. Fig. 95 A good shot of the filter-3.01 shown Fig. 96 Although most use the dipstick tube to remove the old engine oil, certain engines may use a separate tube ENGINE AND DRIVE MAINTENANCE 2-33 5. Position a drain pan, or a cut-down milk jug under the oil filter. Some filters are mounted horizontally and some vertically. In either case, there is usually oil left in the filter. When the filter is removed, oil will flow out of the engine and the filter. If you are not prepared, you will have a mess on your hands. It may also be necessary to use a funnel or fashion some type of drain shield to guide the oil into the drain pan. This can be as simple as a recycled oil bottle with the bottom cut off or an elaborate creation made of tin. In any case, its purpose is to prevent oil from spilling all over the engine and bilge. 6. To remove the filter, you will probably need an oil filter strap wrench (available at almost any place that sells marine or automotive parts and fluids). Heat from the engine tends to tighten even a properly installed filter and makes it difficult to remove. Place the wrench on the filter as close to the engine as possible, while still leaving room to work. This will put the wrench at the strongest part of the filter (near the threaded end) and prevent crushing the filter. Loosen the filter with the wrench using a counterclockwise turning motion Some later models may utilize a remote oil filter. 7. Once loosened. wrap a rag around the filter and unscrew it from the boss on the engine. Make sure that the drain pan and shield are positioned properly before you start unscrewing the filter. Should some of the hot oil happen to get on your hands and burn you, dump the filter into the drain pan. Fig. 97 On the newer engines with fuel injection shown), the remote filter is on the port side near the top Fig. 99 Removing the oil filter Fig. 98 On the older engines and most engine with a carburetor shown), look on the side of the engine block 8. Wipe the base of the mounting boss with a clean, dry lint-free rag. If the filter is installed vertically, you may want to fill the filter about half way with oil prior to installation. This will prevent oil starvation when you fire the engine up again. Pre-filling the oil filter is usually not possible with horizontally mounted filters. Smear a little bit of fresh oil on the filter gasket to help it seat properly on the engine. 9. Install the filter and tighten it approximately a quarter-turn after it contacts the mounting boss (always follow the filter manufacturer's instructions). This usually equals "hand tight." Using a wrench to tighten the filter is not required, nor should it be considered. Never operate the engine without engine oil. Severe and costly engine damage will result in a matter of seconds without proper lubrication. If any has gotten into the remove usrng an pad These pads are specially formulated to only absorb and not soak up any water the bilge Perform a and make sure all are 11. Carefully remove the drain pan from under the oil filter and transfer the oil into a suitable container for recycling. 12. Refill the engine with the proper quantity and quality of oil immediately (see the Capacities chart). You may laugh at the severity of this warning, but if you wait to refill the engine and someone unknowingly tries to start it, severe and costly engine damage will result. 13. Refill the engine crankcase slowly through the filler cap on the cylinder head cover. Use a funnel as necessary to prevent spilling oil. Check the level often. You may notice that it usually takes less than the amount of oil listed in the chart to refill the crankcase. This is onlv until the engine is started and the oil filter is filled with oil. 14. To make sure the proper level is obtained, run the engine to normal operating temperature, turn the engine OFF, allow the oil to drain back into the oil pan and recheck the level after about 5 minutes. Top off the oil to the correct mark on the dipstick. 1- Filter 2-Sealing Ring Fig. 100 Before installing the new filter, wipe the gasket mating surface clean I I Fig. 101 Dip a finger into a fresh bottle of oil, and lubricate the gasket of the new filter contacts the mating surface. Do not use a wrench to the 2-34 ENGINE AND DRIVE MAINTENANCE FLUID LEVEL See Figures 103 and 104 SY Power steering fluid level should always be checked with the engine hot if at all possible. Start the engine and run it until it reaches normal operating temperature. 2. Rotate the steering wheel lock-to-lock about 10 times to ensure that the fluid is warm. 3. Turn the engine OFF and place the drive unit so that it is straight back. 4. Locate the dipstick cap on top of the power steering fluid reservoir. Unscrew the cap and remove the dipstick. Wipe down the dipstick with a clean rag and reinsert it into the reservoir making sure that the cap is screwed all the way down. 5. Remove the dipstick again and check that the fluid level is up to the FULL HOT mark (FULL COLD if the level is being checked cold). If the level between the FULL mark and the indent on the stick, it's OK. Below the or hash mark and you must add fluid. Use OMC Power Steering Fluid, GM Power Steering Fluid, or ATF fluid. Do not overfill! 6. It is always a good idea to bleed the system after adding fluid. BLEEDING THE SYSTEM It is important that all air be removed from the system after filling or component removal. If air is left in the system, the fluid in the pump may foam during operation causing discharge or spongy steering. With the engine stopped and the drive unit positioned straight back, check that the fluid level is at the FULL COLD mark on the dipstick. 2. Turn the steering wheel all the way over to Port and then check the fluid level again. Add fluid if necessary. 3. Install the capldipstick onto the reservoir, start the engine and run it at idle for a minute and then shut it OFF again. Remove the reservoir cap allowing any foam in the pump to escape. 4. Reinsert the and check the fluid again, making sure that it is at the FULL HOT mark this time. Add fluid as necessary. Repeat this step as necessary until the system no longer requires fluid. 5. Start the engine again and move the steering wheel slowly from lock to lock several times. Remember the reservoir cap should still be off, so while you're moving the wheel, observe the fluid level in the reservoir-it should be above the pump body, if not, carefully add fluid so that the level stays above the body. 6. Fluid containing air will be foamy and light red or tan in color. This is normal, but you must make sure that the fluid level is high enough so that the foam DOES NOT enter the pump Continue moving the wheel and adding fluid until there is no foam left, indicating the absence of air bubbles. If you see excessive foaming during the previous step, shut the engine down and let everything sit for 30 minutes before trying it again. 7. Once the foam has disappeared, position the steering wheel at the center position and shut the engine Off. Screw in the capldipstick and recheck the fluid level. If not at the FULL HOT level, add fluid slowly until it is. ENGINE AND DRIVE MAINTENANCE 2-35 Fig. 103 Typical power steering pump I All engines covered in this manual utilize one of two cooling systems, or variations thereof. Simply, there is a Seawater Cooling system, sometimes called Raw Water system and a Closed Cooling system. Seawater systems are just that ...they utilize the water that the boat is operating in to cool and lubricate the drive and engine. Water is drawn in through the stern drive and circulated to, and through, the engine and its components. The heated water is then returned overboard through the exhaust system. Closed Cooling systems are actually two systems working together; a seawater system and a closed system consisting of antifreeze-very similar to an automotive system, without the radiator. The two systems work together in a variety of ways. Complete information on individual system operation, and component repair procedures is detailed in the Cooling Systems section. In this section we will only deal with checking fluid levels, draining and filling, and flushing the systems. LEVEL CHECK Closed Cooling System Only See Figure 105 Always allow the engine to cool down before checking the coolant level. If possible, check cold. Opening a pressure cap with the engine hot can cause a violent discharge of steam and water, resulting in severe injury. If the engine is anything but cold, always remove the cap a quarter turn at a time in order to allow any residual pressure to escape slowly. 1. Remove the pressure cap at the top of the heat exchanger. Coolant should be visible at the bottom of the filler neck, or within 1 in. of the bottom of the neck. 2. Reinstall the cap on the heat exchanger making sure that it seats on it's stops on the filler neck. 3. Start the engine and run it until it reaches normal operating temperature. Turn off the engine and check that the coolant level is to the FULL line on the side of the coolant recovery tank. 4. Fill the system with a 50150 mixture of distilled water and ethylene glycol antifreeze. FLUSHING THE SYSTEM If your boat is operated in mineral fresh severely polluted water, flush the cooling system regularly-after each usage if at all possible! Always flush system before draining winter storage. Fig. 104 Power steering fluid dipstick Fig. 105 Check that the coolant level is to the FULL line on the coolant recovery tank when the engine is hot (early model shown, late models utilize a rectangular tank 1 Coolant Recovery Reservoir Seawater Svstems Fresh Water Flush Out Of Water See Figure 106 NEVER run the engine when the boat is out of the water without water being supplied to the stern drive. Connect a flushing attachment over the water intake openings in the stern drive gear housing. These devices are available at your local OMC dealer or through a variety of aftermarket suppliers. 2. Connect a garden hose between the flushing attachment and a water spigot. 3. Open the slowly, no more than half way, and allow the drive and cooling system to fill completely. You'll know the system is full when water begins to flow out of the drive unit, or through the propeller on closed systems. 2-36 ENGINE AND DRIVE MAINTENANCE Never allow the water to reach the flushing device at anything more than low pressure. 4. With the drive in Neutral, start the engine and let it idle for 10 minutes or until the water being discharged is clear and then turn the engine off. Never run the engine above 1500 rpm with the flushing device attached and always keep an eye on the temperature gauge incase the engine begins to overheat. 5. Turn off the water from the disconnect the and remove the flushing attachment. Boat In Wafer See Figure 106 If your boat has a (a water inlet valve), it must remain closed during this procedure in order to prevent water from flowing back into the boat. If your does not have a locate the water inlet hose at the seawater supply pump, disconnect it and plug it. We highly recommend that you leave a note to yourself in the vicinity of the ignition key reminding of the fact that this procedure has been done so that you, or someone else doesn't the engine after flushing without reopening the or reconnecting the inlet hose. Seem silly? Do it anyway! 1. Raise the stern drive unit to the full UP position. 2. Connect a flushing attachment over the water intake openings in the stern drive gear housing. These devices are available at your local OMC dealer or through a variety of aftermarket suppliers. 3. Connect a garden hose between the flushing attachment and a water spigot. 4. Lower the stern drive unit to the full position. 5. Open the slowly, no more than half way, and allow the drive and cooling system to fill completely. You'll know the system is full when water begins to flow out of the drive unit, or through the propeller on closed systems. Flushing Attachment 2-Water Hose Fig. 106 Attach a flushing device to the drive unit when flushing the cooling system Never allow the water to reach the flushing device at anything more than low pressure. 6. With the drive in Neutral, start the engine and let it idle for 10 minutes or until the water being discharged is clear and then turn the engine off. Never run the engine above 1500 rpm with the flushing device attached and always keep an eye on the temperature gauge incase the engine begins to overheat. 7. Turn off the water from the 8. Raise the drive unit to the UP position again, disconnect the hose and remove the flushing attachment. 9. Lower the unit and make sure you open the and reconnect the inlet hose (don't forget to unplug it first!). Seawater Systems With Fresh Water Flush See Figure 107 Do not, under any circumstance, start the engine while performing this procedure! 1. Locate the flush valve connected to a black hose on the side of the engine. There should be flush socket attachment with a cap connected to it. 2. Remove the socket from the cap, connect a garden hose and then plug into the flush valve. 3. Turn the hose spigot to its highest pressure and allow the engine to flush for 5 minutes. 4. Turn off the water and remove the from the valve. 5. Unscrew the socket from the hose and insert it back into the cap. 6. You're done! That was easy-now you know why people spend the time and money to retro-fit these onto their engines.. Fig. Certain late model engines may be equipped with a fresh water flushing attachment (or have been retro-fitted), making it much easier to regularly flush your cooling system Closed Systems The very name of this systems implies that it is not necessary to flush it. If for some reason you absolutely must flush the closed portion of this system, simply follow the drain and fill procedures. Remember though that the closed system uses a conventional seawater cooling system in conjunction with its closed portion-this system MUST be flushed on a regular basis and all procedures are detailed previously under Seawater Systems. ENGINE AND DRIVE MAINTENANCE 2-37 PRESSURE CAP TESTING Closed System Only See Figures 108,109 and 110 The pressure cap on the coolant reservoir is designed to maintain closed system pressure at approximately 14 psi when the engine is at normal operating temperature. Clean, inspect and pressure test the cap at the end of your first season and then every 100 hours (or once a year) thereafter. Make sure the engine is cool before attempting to remove the cap. To be safe, always turn the cap 114 turn and allow any residual pressure to escape before removing it completely. Use a heavy rag or wear gloves. 1. Remove the cap and wash it thoroughly to remove any debris from the sealing surfaces. 2. Inspect the gasket and rubber seal for tears, cuts or cracks. If you notice anything, we recommend replacing the entire cap although you can replace the gasket on some older engines if you like. 3. Make sure that the locking tabs on the cap are not bent or damaged in any way. If so, replace the cap. 4. Use a cooling system pressure tester and, following the manufacturer's instructions, install the cap. Check that the cap relieves pressure at 14 psi and holds pressure for 30 seconds without falling below psi. Replace the cap if it fails. 5. Check the inside of the filler neck for debris; it should be completely smooth. Check that the lock flanges on the filler neck are not bent or damaged and then install the cap. PRESSURE TEST Closed System Only SY Make sure the engine is cool before attempting to remove the cap. To be safe, always turn the cap 114 turn and allow any residual pressure to escape before removing it completely. Use a rag or wear gloves. 1. Remove the pressure cap from the reservoir or heat exchanger. 2. Perform the pressure cap Testing procedure. If the cap is bad, this may be your problem. Replace the cap and ensure that the problem does not go away; if it persists, move to the next step. 3. Add coolant so that the level is within one inch of the bottom of the filler neck. Attach a cooling system pressure tester to the filler neck and pressurize the system to 17 psi. 4. Watch the gauge for about 2 minutes. If the pressure remains steady, you're OK. If the pressure drops, move to the next step. 5. Maintain the specified pressure and check the entire closed system for any leaks-hoses, plugs, petcocks, pump seals, etc.). Also, listen very closely for any hissing or bubbling. 6. If you've still not found any leaks, test the heat exchanger as detailed in the Coolina section. 7. If the exchanger is OK then you most likely have an problem with loose head bolts, a bad head gasket or a warped cylinder head, not the cooling system. DRAINING & DERATE V The cooling system should be drained, cleaned, and refilled each season, although recommendations are for every two years on normal anti- freeze systems. We think its cheap insurance to do it every season, but you certainly can't go wrong by following the factory's suggestion. The bow of the boat must be higher than the stern to properly drain the cooling system. If the bow is not higher than the stern, water will remain in the cylinder block and in the exhaust manifold. Insert a piece of wire into the drain holes, but not in the to ensure sand, silt, or other foreign material is not blocking the drain opening. If the engine is not completely drained for winter storage, trapped water can freeze and cause severe damage. The water in the oil cooler-if so equipped-must also be drained. Seawater System--4 Cylinder Engines See Figure 111 DERATE If the boat is in the water, close the to from entering the cooling system. If the boat is not equipped with a disconnect the seawater inlet line and plug it. Make sure you leave yourself a note by the ignition switch reminding yourself to turn the valve back on or connect the line, especially if the boat is going to sit for a period of time. Sound silly? Do it! 2. Position suitable containers under all drain plugs and hoses (if space permits) to catch any water being drained or else it will collect in the bilge. 3. Loosen the clamp and disconnect the long supply hose at the thermostat housing. Slowly lower the hose and allow the water to drain. 4. Loosen the clamp and disconnect the large house running from the thermostat housing to the engine water pump, at the pump. Allow all water to drain. 5. Remove the drain plug on the side of the cylinder block (port on starboard on and allow all water to drain, 6. Remove the drain plug on the exhaust manifold or elbow. If your engine is not equipped with a drain, simply disconnect the hose from the lower fitting. 7. On models equipped with power steering, disconnect the lower seawater hose at the cooler-some models may actually have a drain plug on the bottom side of the cooler. If the cooler is mounted horizontally, loosen the mounting bolt and tilt the cooler to aid in the draining. 8. Loosen the clamps and disconnect both hoses at the seawater pump (if equipped). Allow all water to drain and then reconnect the hoses. 9. On engines with closed cooling, remove the drain plug from the bottom of the heat exchanger. If there is no plug, disconnect the seawater inlet hose at the bottom of the exchanger. 10. Disconnect and remove the lower end of any other hoses and hold them as low as possible while draining. Reconnect when all water has stopped draining. On models with closed cooling, refer to the flow diagrams in the Cooling section so that you do not disconnect any hoses used for the closed portion of the system. Rubber Seal 2-Gasket 3-Locking Tabs Fig. 108 Check the pressure cap carefully. .. 1-lnspect for damage 2-Clean coolant recovery Fig. 109 ...and then check the filler neck Fig. 110 Using a pressure tester to check the 2-38 E AND DRIVE Fia. 111 Both drain are on the oort shown 11. a stiff piece of wire, clean out all drain holes. Don't drain holes the drive unit! 12. Tilt the drive unit to the full UP position and then remove the water drain plug from the port side of the pivot housing; this can be found toward the front the upper housing where it the bell housing. 13. Turn the ignition switch ON and crank the engine over a few times to force out any residual water in the block or seawater pump, DO NOT START THE ENGINE! 14. Coat the threads of all drain plugs with sealer and then reinstall them. Tighten the plugs and securely. 15. If you are winterizing the boat and its going to sit for a months, it's a good idea to remove the thermostat housing and fill the cylinder block and head with a mixture of water and Remove the inlet line at the exhaust manifold and do the same. Make sure you drain all coolant into a suitable container prior to refilling the system with seawater next season. 16. If you closed the or disconnected the water inlet line, make sure you open or reconnect it PRIOR to restarting the engine. Seawater And V8 Engines See Figures Specific drain locations and disconnections vary from engine to engine. Please review the following items for the actual description for your engine before beginning the procedure: 1987-90 long hose at thermostat housing, large hose at engine water pump running from thermostat housing, starboard side exhaust manifold and port side cylinder block If equipped with power steering or other oil cooler, remove the drain plug or lowest hose at the cooler. engines-long hose at thermostat housing, large hose at engine water pump running from thermostat housing, port side exhaust manifold and port side cylinder block If equipped with power steering or other oil cooler, remove the drain plug or lowest hose at the cooler. engines-long hose at thermostat housing, large hose at engine water pump running from thermostat housing, exhaust manifold and cylinder block on port and starboard sides. If equipped with power steering or other oil cooler, remove the drain plug or lowest hose at the cooler. 1988-95 engines-long hose at thermostat housing, large hose at engine water pump running from thermostat housing, cylinder block on port and starboard sides, hose at aft end of each exhaust manifold. If equipped with power steering or other oil cooler, remove the drain plug or lowest hose at the cooler. engines-long hose at thermostat housing, large hose at engine water pump running from thermostat housing, cylinder block on port and starboard sides, hose at aft end of each exhaust manifold. If equipped with power steering or other oil cooler, remove the drain plug or lowest hose at the cooler. On engines, remove the bypass hose at the check valve also. 1986-88 and engines-long hose at thermostat housing, large hose at engine water pump running from thermostat housing, cylinder block on port and starboard sides, two rubber caps at fore and aft sides of each exhaust manifold. If equipped with power or other oil cooler, remove the drain plug or lowest hose at the cooler. 1998 engines-large hose at engine water pump running from thermostat housing, cylinder block on port and starboard sides, rubber hose at aft end of each exhaust manifold. If equipped with power steering or other oil cooler, remove the drain plug or lowest hose at the cooler. 1989-96 engines-long hose at thermostat housing, large hose at engine water pump running from thermostat housing, cylinder block on port and starboard sides, rubber capihose at aft end of each exhaust manifold. If equipped with power steering or other oil cooler, remove the drain or lowest hose at the cooler. On enaines, remove the bypass at the check valve also. engines-large hose at engine water pump running from thermostat housing, cylinder block on port and starboard sides, rubber hose at aft end of each exhaust manifold. If equipped with power steering or other oil cooler, remove the drain plug or lowest hose at the cooler. On Gi and engines, remove the small bypass hose at the top of the thermostat housing also. 1989-90 and engines-long hose at thermostat housing, large hose at engine water pump running from thermostat housing, cylinder block on port and starboard sides, exhaust manifold on port and starboard sides, rubber cap at aft end of each exhaust manifold. If equipped with power steering or other oil cooler, remove the drain plug or lowest hose at the cooler. Fig. 112 Port drain engines Fig. 113 Starboard drain engines ENGINE AND DRIVE MAINTENANCE 2-39 Fig. 115 Starboard drain locations-5.01 Ford engines; similar Fig. 116 Disconnect the long water supply GM engines; and the small by-pass engines, others similar Fig. 117 Loosen the starboard drain GM engines, others similar I 1991-96 and engines-long hose at thermostat housing, large hose at engine water pump running from thermostat housing, cylinder block on port and starboard sides, rubber caplhose at aft end of each exhaust manifold. If equipped with power steering or other oil cooler, remove the drain plug or lowest hose at the cooler. On Fi and engines, remove the bypass hose at the check valve also. 1988-98 engines-long hose at thermostat housing, large hose at engine water pump running from thermostat housing, cylinder block on port and starboard sides, rubber caplhose at aft end of each exhaust manifold. If equipped with power steering or other oil cooler, remove the drain plug or lowest hose at the cooler. On Gi and engines, remove the bypass hose at the check valve also. 1987-90 engines-long hose at thermostat housing, large hose at engine water pump running from thermostat housing, cylinder block on port and starboard sides, rubber caplhose at aft end of each exhaust manifold. If equipped with power steering or other oil cooler, remove the drain plug or lowest hose at the cooler. If the boat is in the water, close the to prevent water from entering the cooling system. If the boat is not equipped with a disconnect the seawater inlet line and plug it. Make sure you leave yourself a note by the ignition switch reminding yourself to open the valve or reconnect the line, especially if the boat is going to sit for a period of time. Sound silly? Do it! Fig. 118 Loosen the port drain engines, others similar ENGINE AND DRIVE MAINTENANCE 2-41 opening and then reinstall the dipstick and washer. FLUID LEVEL See Figures 121,122,123 and 124 Check the fluid level after the first 20 hours of operation and then at least every 50 hours of operation or once a season, whichever comes first. It's never a bad idea to check your unit more frequently, particularly if you use your boat in severe service conditions, We recommend checking the fluid level weekly as air pockets during a fluid fill or change may cause an initially false reading; which is to say that the initial level may drop on its own over the first 10 hours of operation or so. OMC recommends using OMC Hi-Vis Gear Case Lubricant in 1986-93 drives, OMC Ultra HPF Gear Case lube in 1994-95 drives, and Mobilube ISHC Fully Synthetic SAE 75W-90 gear lubricant in 1996-98 units. Never substitute regular automotive grease. 1. Position the drive unit in the full position so that the ventilation plate is level. The oil level should always be checked with the drive unit cold. 2. Remove the oil level dipstick found on top of the upper gear unit wipe it down with a clean lint-free rag and reinsert it. Remove it once again and check that the lubricant is up to the line on the stick. If the level is satisfactory, check the condition of the washer and then install it and the dipstick. It's a good idea to replace the washer on a regular basis regardless of its visible condition. 3. If the level is low, add oil lubricant, very slowly, through the dipstick Fig. 122 Use the dipstick to check the fluid level-Cobra and King Cobra models it sit for a moment and then recheck it. The unit should never require more than 2 of lubricant. If more is required, you've got an oil leak and the unit should not be operated until it is found and fixed. 5. Clean any excess oil from the housing. Recheck the oil level on the dipstick again a final time after the next use. Fig. 123 Use the dipstick to check the fluid level-SPIDP models CHECKING FOR WATER It is a good idea to check the unit periodically for water Water in the drive oil usually indicates a bad seal somewhere on the unit and should be corrected immediately. With the engine off and the stern drive, unit cold, trim the drive to the full UP position. 2. Remove the oil plug and take a small sample of the lubricant-a teaspoon worth is more than enough. 3. If the oil sample looks milky brown then there is likely a leaking seal in the drive unit and it should be located and replaced before operating the boat again. 4. Most units covered in the manual have maanetic so be sure to check that the end of the plug is free of metal filings. you find any metallic particles on the plug it can be an indication of greater Fig. 121 A close up of the oil dipstick nut shown) problems within the drive unit. I 2-42 ENGINE AND DRIVE MAINTENANCE Fig. 124 The top of the flat area indicates the case is full 3. When the old oil has completely drained, install the drain plug and , . . tighten it securely. 4. Remove the oil fill on the starboard side of the drive, above the anti-cavitation plate. the dipstick into the hole so that just resting on the upper surface of the bore; do not screw it in. 5. Pump the proper lubricant into the drive through the fill hole until it reaches upper mark on the dipstick. This will give a false reading (slightly high) in order to account for a fluid level drop once the air bubbles are purged when you start the engine. Please refer to the Capacities chart for lubricant capacities on a specific drive unit. Fill the drive unit slowly! Adding lubricant too quickly will cause too many air bubbles and could lead to an inaccurate level reading or even more severe damage. 6. With the lube pump still attached, screw in the oil level dipstick securely. Quickly remove the pump and install the fill plug and washer. 7. After allowing the oil to settle for a few minutes, check the level using the dipstick. Add lubricant slowly through the dipstick hole as required. 8. Clean any excess oil on the housing. Check the oil level a final time and then recheck it again after the first use. 1989-92 King Cobra Units See Figure 126 Stern drive oil should always be changed with the unit cold. Take a look at the oil as it is being drained, if the oil is milky brown in color there is a good chance there is a leak in the unit. The stern drive unit should not be operated until the leak is found and corrected. Trim the stern drive to the full position. 2. Position an oil drain pan or an old plastic milk jug under the drain hole on the bottom of the drive unit and then remove the drain plug (port side of lower gearcase). Removing the oil dipstick at this time will help the oil drain quicker. DRAIN AND REFILL The oil in the stern drive should be changed at least every 50 hours of operation or twice a season on Cobra and King Cobra hours of operation or once a season on drives; whichever comes first. never a bad idea to change the fluid in your unit more frequently, particularly if you use your boat in severe service conditions. OMC recommends using only OMC Hi-Vis Gear Case Lubricant in 1986-93 drives, OMC Ultra HPF Gear Case lube in 1994-95 drives, and Mobilube 1 SHC Fully Synthetic SAE 75W-90 gear lubricant in 1996-98 units. Never substitute regular automotive grease. 1986-93 Cobra Units See Figure 125 Stern drive oil should always be changed with the unit cold. Take a look at the oil as it is being drained, if the oil is milky brown in color there is a good chance there is a leak in the unit. The stern drive unit should not be operated until the leak is found and corrected. Trim the stern drive to the full position. 2. Position an oil drain pan or an old plastic milk jug under the drain hole on the bottom of the drive unit and then remove the drain plug (starboard side of lower gearcase). Removing the oil dipstick at this time will help the oil drain quicker. Fig. 125 The oil drain plug is on the starboard side of the housing ENGINE AND DRIVE MAINTENANCE 2-43 3. When the old oil has completely drained, install the drain plug and tighten it securely. 4. Pump the proper lubricant into the drive through the oil dipstick hole until it reaches the upper mark on the dipstick with the dipstick just sitting in the bore--do not screw it into the hole. This will give a false reading (slightly high) in order to account for a fluid level drop once the air bubbles are purged when you start the engine. Please refer to the Capacities chart for lubricant capacities on a specific drive unit. Fill the drive unit slowly! Adding lubricant too quickly will cause too many air bubbles and could lead to an inaccurate level reading or even more severe damage. 5. After allowing the oil to settle for a few minutes, check the level using the dipstick. Add lubricant slowly through the dipstick hole as required. 6. Clean any excess oil on the housing. Check the oil level a final time and then recheck it again after the first use. 1993-95 King Cobra Units See Figure 126 Stern drive oil should always be changed with the unit cold. Take a look at the oil as it is being drained, if the oil is milky brown in color there is a good chance there is a leak in the unit. The stern drive unit should not be operated until the leak is found and corrected. 1. Trim the stern drive to the full position. 2. Position an oil drain pan or an old plastic milk jug under the drain hole on the bottom of the drive unit and then remove the plug (port side of lower gearcase). Removing the oil dipstick at this time will help the oil drain quicker. 3. When the old oil has completely drained, install an appropriate pump into the drain plug and tighten it securely. OIL OPENING Fig. 126 The oil drain plug is on the port side of the housing 4. Pump the proper lubricant into the drive until it reaches the upper mark on the dipstick with the dipstick just sitting in the bore--do not screw it into the hole. This will give a false reading (slightly high) in order to account for a fluid level drop once the air bubbles are purged when you start the engine. Please refer to the Capacities chart for lubricant capacities on a specific drive unit. Fill the drive unit slowly! Adding lubricant too quickly will cause too many air bubbles and could lead to an inaccurate level reading or even more severe damage. 5. With the lube pump still attached, thread in the dipstick and tighten it securely. Quickly remove the pump and install the fillidrain plug and washer; tighten it to 60-84 inch Ibs. Nm). Reinstall the oil level dipstick with a new seal and tighten it to 48-72 inch Ibs. (5.4-8.1 Nm). Use sealing compound on the threads of the oil fillidrain and level plugs. 6. After allowing the oil to settle for a few minutes, check the level using the dipstick. Add lubricant slowly through the dipstick hole as required. 7. Clean any excess oil on the housing. Check the oil level a final time and then recheck it again after the first use. 1994-95 Cobra Units And 1996-98 SP Units See Figures 127,128 and 129 Stern drive oil should alwavs be chanaed with the unit cold. Take a look at the oil as it is being drained, if the oil is milky brown in color there is a good chance there is a leak in the unit. The stern drive unit should not be operated until the leak is found and corrected. 1. Trim the stern drive to the full position. 2. Position an oil drain pan or an old plastic milk jug under the drain hole on the bottom of the drive unit and then remove the plug (port side of lower gearcase). Remove the oil dipstick at this time which will help the oil drain quicker. 3. While waiting for the oil to drain, remove the three shift lever cover retaining screws (two on the upper gear housing, one on the intermediate housing). Remove the cover and then remove the oil level plug to starboard of the shift lever. 4. When the old oil has completely drained, position and install a suitable lubricant pump into the drain hole. 5. Pump the proper lubricant into the drive through the fillidrain hole until it reaches the level at the bottom of the oil level hole on the upper gear housing. Please refer to the Capacities chart for lubricant capacities on a specific drive unit. Fill the drive unit slowly! Adding lubricant too quickly will cause air bubbles that could lead to an inaccurate level reading or even more severe damaae. 6. With the lube pump still attached, reinstall the oil level plug with a new seal, tighten it to 48-72 inch Nm). Do the same with the oil dipstick and then quickly remove the pump and install the fillidrain plug and washer; tighten it to 60-84 inch (6.8-9.5 Nm). Use sealing compound on the threads of the oil fillidrain and level plugs. 7. After allowing the oil to settle for a few minutes, check the level using the dipstick. Add lubricant slowly through the dipstick hole as required. 8. Install the shift cover and tighten the three bolts to 108-132 inch Ibs. (12.2-14.9 9. Clean any excess oil on the housing. Check the oil level a final time and then recheck again after the first use. 2-44 ENGINE AND DRIVE MAINTENANCE Fig. 128 ...remove the oil level plug Fig. 127 After removing the shift cover... Fig. 129 The oil drain plug is on the port side of the housing 1996-98 DP Units See Figures 127 thru 131 Stern drive oil should always be changed with the unit cold. Take a look at the oil as it is being drained, if the oil is milky brown in color there is a good chance there is a leak in the unit. The stern drive unit should not be operated until the leak is found and corrected. Remove the as detailed in the Drive Systems section. 2. Trim the stern drive to the full position. 3. Position an oil drain pan or an old plastic milk jug under the bottom of the drive unit and then remove the fillidrain plug just inside the lower gear case housing, under the propeller shaft. Remove the oil dipstick at this time which will help the oil drain quicker. 4. While waiting for the oil to drain, remove the shift lever cover retaining screws (one, two or three depending on the model, but usually three). Remove the cover and then remove the oil level plug to starboard of the shift lever. 5. When the old oil has completely drained, position and install a suitable lubricant pump into the drain hole. Almost all models will require first screwing in a Fill Adaptor (# 3855932-4) Fig. 130 The oil drain plug is inside the housing, behind the propellers... 6. Pump the proper lubricant into the drive through the fillidrain hole until it reaches the level at the bottom of the oil level hole on the upper gear housing. Please refer to the Capacities chart for lubricant capacities on a specific drive unit. Fill the drive unit slowly! Adding lubricant too quickly will cause air bubbles that could lead to an inaccurate level reading or even more severe damage. 7. With the lube pump still attached, reinstall the oil level plug with a new seal, tighten it to 48-72 inch (5.4-8.1 Nm). Do the same with the oil dipstick and then quickly remove the pump and fill adaptor and install the plug and washer; tighten it to 60-84 inch (6.8-9.5 Nm). Don't forget to replace the O-rings when replacing the plugs! ENGINE AND DRIVE MAINTENANCE 2-45 1-Plug 2-Sealing Washer or 0 -Ring Fig. 131 ...don't forget to replace that O-ring! Fig. 132 Remove the screw to check the fluid level 1. Position the stern drive in the full UPIOUT position in order to relieve all hydraulic pressure. Failure to position the drive unit in the full position before removing the plug could result in hydraulic fluid spraying all over upon removal. 2. Loosen and remove the fill screw from the side of the pump housing. 3. Check that the lubricant is up to the bottom of the threads in the hole. If necessary, add more fluid slowly through the hole the level is correct. 4. With the fill screw still out, move the drive through its full range 6-10 times in order to purge any air that may have entered the system. Lower the drive fully and recheck the fluid level again; repeat the process if necessary. 5. Install the fill screw and tighten it securely. 8. Install the propellers. 9. After the oil to settle for a few minutes, check the level using the dipstick. lubricant slowly through the hole as required. Install the shift cover and tighten the retaining bolts to 108-132 inch Ibs. (12.2-14.9 Nm). 11. Clean any excess oil on the housing. Check the oil level a final time and then recheck it again after the first use. FLUID LEVEL See Figure 132 Fluid levels in the power pump should be checked every 100 hours of operation or once a season, whichever comes first. We recommend that you use OMC Power Power Steering Fluid, although OMC suggests that in a pinch you can use ATF. Although OMC does not publish intervals for propeller shaft lubrication, we recommend lubricating the shaft every 100 hours or 6 months, whichever Lubricate the cable pivot points every 100 hours or 6 months, whichever section for details on propeller removal and installation. lubricate every 50 hours or 2 months whichever comes first. Always use OMC Grease. comes first when the vessel is being in fresh water. If the vessel is Lubricate the cable pivot points every 100 hours or 6 months, whichever comes first when the vessel is being operated in fresh water. In salt water, lubricate every 50 hours or 2 months whichever comes first. Always use OMC Grease. 2-46 ENGINE AND DRIVE MAINTENANCE See Figure 133 Always check the steering system and its components for loose, missing or damaged components and fittings before performing your lubrication procedures. Lubricate the various steering system components every 50 hours or 2 months, whichever comes first when the vessel is being operated in fresh water. In salt water, lubricate every 25 hours or 30 days whichever comes first. Use only OMC Triple-GuardGrease The transom end of the steering cable must be fully retracted into the cable housing before applying grease to the fitting. Lubricate all pivot points on the system with SAE 20 or 30 motor oil. The control valve grease fitting takes OMC Triple-Guard Grease as does the steering ram. Use only a hand operated grease gun when filling the zerk fitting. Never use a power operated gun! Fig. 133 Always use a hand operated grease gun when filling the valve + See Figures 134 and 135 The gimbal bearing and the U-Joints must be lubricated every 100 hours of operation, or once a season; whichever comes first. OMC EP Wheel Bearing Grease should be used in both instances. Certain older units may not be equipped with grease fittings; if yours is not, the U-joints will require disassembly and greasing. Because OMC recommends removing the drive unit prior to performing this service, the perfect time to consider performing it is during your winterization. Failure to perform this service on a regular basis will result in severe damage to the transom assembly and drive unit. Remove the drive unit as detailed in the Drive Unit section. Carefully support it in a holding assembly. 2. Connect a hand operated grease gun to the fitting for the bearing and slowly pump in grease until the all of the old grease has been forced out. Take note of the old grease as it is expelled-if any evidence of water is observed, inspect the bearing for damage and replace as necessary. 3. Now connect the grease gun to one of the fittings for the U-joints and slowly pump in grease until the all of the old grease has been forced out. Repeat this procedure for the second being careful to force ALL of the old grease out. Use only a hand operated grease gun when filling the zerk fitting. Never use a power operated gun! Wipe all old grease off of the driveshaft splines and then coat the splines thoroughly new grease. 5. Carefully wipe any grease, oil or dirt from the two O-rings at the top of the shaft and then coat them thoroughly with light oil. 6. Check the bellows for of damaae or deterioration, replacing if in doubt (as detailed in the 7. Check the engine alignment and then reinstall the drive unit. Fig. 134 The gimbal bearing is serviced via a grease (zerk) fitting on the starboard side of the housina Fig. 135 Each of the U-Joints has a grease fitting. Don't forget to lube the two O-rings at fhe end of the shaft ENGINE AND DRIVE MAINTENANCE 2-47 Probably the biggest surprise for boat owners is the extent to which mold and mildew develop in a boats interior. Preventing this growth is a two-fold process. First, the boat's interior should be thoroughly cleaned. Second, ventilation should be provided to allow adequate air circulation. Properly cleaning the boat includes removing as much as possible from it. The less there is on a boat, the less there is to attract mildew. Clothing, foul weather gear, shoes, books, charts, paper goods, leather, bedding, curtains, food stuffs, first aid supplies, odds and ends, etc., should be taken home. They're all fertile soil for mildew, as is dirt, grease, soap scum, etc. The next step is to vacuum, scrub and polish every surface, especially galley and head surfaces. Use a polish that leaves a protective coating on which it's hard for mold to get a foothold. Mildew-preventive sprays are available for carpets and furniture. The cleaner and more highly polished the insides of lockers, cabinets, refrigerators, icemakers, drawers and shower stalls are when you leave them, the less likely it is you'll find mold. Marine stores sell cleaners and polishes specifically for boats and for the marine environment. Many people find that regular household products are satisfactory. It's the elbow grease that counts. If dirt and grease are the growing medium, stagnant air is the fertilizer for mold and mildew (mildew is a form of mold). The more freely air can circulate in the interior of your boat the less conducive conditions will be for the growth of mold. Openings or vents at each end near the top can be fashioned to let air in. Flaps or stovepipe elbows can be used to keep rain out. Hatches and windows can then be left partially open. Visiting the boat on dry, sunny days and opening it up as much as possible is a great way to let fresh air in. Do this whenever possible. The best way to protect navigation and communications equipment from deteriorating is to remove the units from the boat. Wrap them in towels, not plastic, and take them home. Television sets, VCRs and stereos should also be removed to keep them safe and to keep cold and dampness from affecting them adversely. Before storing electronics equipment, clean off the terminals and the connecting plugs and spray them with a displacing lubricant that specifically says it's intended for use on electronics. Antennas should also be stored in a safe, dry place to protect them from both the elements and accidental damage. All terminal blocks, junction blocks, fuse holders and the back of electrical panels should be cleaned and sprayed with an appropriate protectant. Remove any corrosion that has developed. Anything that could be easily stolen, such as anchors, flare guns, binoculars, etc., is best taken home. See Figure 136 Fiberglass reinforced plastic hulls are tough, durable, and highly resistant to impact. However, like any other material they can be damaged. One of the advantages of this type of construction is the relative ease with which it may be repaired. Because of its break characteristics, and the simple techniques used in restoration, these hulls have gained popularity throughout the world. From the most congested urban marina, to isolated lakes in wilderness areas, to the severe cold of northern seas, and in sunny tropic remote rivers of primitive islands or continents, fiberglass boats can be found performing their daily task with a minimum of maintenance. A fiberglass hull has almost no internal stresses. Therefore, when the hull is broken or stove-in, it retains its true form. It will not dent to take an shape set. When the hull sustains a severe blow, the impact will either be absorbed by deflection of the laminated panel or the blow will result in a definite, localized break. In addition to hull damage, bulkheads, stringers, and other stiffening structures attached to the hull may also be affected and therefore, should be checked. Repairs are usually confined to the general area of the rupture. The best way to care for a fiberglass hull is to first wash it thoroughly. Immediately after hauling the boat, while the bottom is still wet, is best, if possible. Remove any growth that has developed on the bottom. Use a pressure cleaner or a stiff brush to remove barnacles, grass, and slime. Pay particular attention to the waterline area. A scraper of some sort may be needed to attack tenacious barnacles. Pot scrubbers work well. Attend to any blisters: don't wait! Fig. 136 The best way to care for a fiberglass hull is to wash it thoroughly to remove any growth that has developed on the bottom Remove cushions and all weather curtains and enclosures and take them home. Make sure they are clean before storing them, and don't store them tightly rolled. After washing the topsides, remove any stains that have developed with one of the fiberglass stain removers sold in marine stores. For stubborn stains, wet-sanding with 600-grit paper may be necessary. Remove oxidation and stains from metal parts. Apply a coat of wax to everything. BELOW WATERLINE See Figure 137,138,139 and 140 A foul bottom can seriously affect boat performance. This is one reason why racers, large and small, both powerboat and sail, are constantly giving attention to the condition of the hull below the waterline. In areas where marine growth is prevalent, a coating of vinyl, anti-fouling bottom paint should be applied. If growth has developed on the bottom, it can be removed with a solution of acid applied with a brush or swab and then rinsed with clear water. Always use rubber gloves when working with acid and take extra care to keep it away from your face and hands. The fumes are toxic. Therefore, work in a well-ventilated area, or if outside, keep your face on the windward side of the work. Fig. 137 This beautiful new fiberglass hull will not stay this good looking for long if it is not protected with anti-foul paint 2-48 ENGINE AND MAINTENANCE Fig. 138 In areas where marine growth is prevalent, a coating of vinyl, anti-fouling bottom paint should be applied Fig. 139 This anti-foul paint has seen better days and must be replaced Fig. 140 This hull is in even worse condition and should be sand blasted and repainted Barnacles have a nasty habit of making their home on the bottom of boats that have not been treated with anti-fouling paint. Actually they will not harm the fiberglass hull, but can develop into a major nuisance. If barnacles or other crustaceans have attached themselves to the hull, extra work will be required to bring the bottom back to a satisfactory condition. First, if practical, put the boat into a body of fresh water and allow it to remain for a few days. A large percentage of the growth can be removed in this manner. If this remedy is not possible, wash the bottom thoroughly with a high-pressure fresh water source and use a scraper. Small particles of hard shell may still hold fast. These can be removed with sandpaper. The idea behind anodes is simple: When dissimilar metals are dunked in water and a small current is leaked between or amongst them, the less-noble metal (galvanically speaking) is sacrificed. The zinc alloy that the anodes are made of is designed to be less noble than the aluminum alloy your drive unit is made from. If there's any electrolysis and there almost always is, the inexpensive zinc anodes are consumed in lieu of the expensive drive. These zincs need a little attention in order to do their job. Make sure they're there, solidly attached to a clean mounting site and not covered with any kind of paint or wax. Periodically inspect them to make sure they haven't eroded too much. At a certain point in the erosion process, the mounting holes start to enlarge, which is when the zinc might fall off. Obviously, once that happens, your drive no longer has any protection. Many offer an option of a or magnesium anode, magnesium actually works better in fresh water never use magnesium in saltwater! If you tend to use your vessel in fresh and saltwater, always go with the zincs. OMC also offers an electronic corrosion control system, Active Protection System which is detailed later in this manual. SERVICING See Figure 141,142 and 143 Depending on what kind of drive your boat has, you might have number of zincs. Regardless of the number, there are some fundamental rules to follow that will give your boat's sacrificial anodes the ability to do the best job protecting your boat's hardware that they can. The first thing to remember is that zincs (or magnesiums) are electrical components and like all electrical components, they require good clean connections. So after you've undone the mounting hardware and removed last year's zincs, you want to get the zinc mounting sites clean and shiny. Get a piece of coarse emery cloth or some 80-grit sandpaper. Thoroughly rough up the areas where the zincs attach (there's often a bit of corrosion residue in these spots). Make sure to remove every trace of corrosion. Zincs are attached with stainless steel machine screws that thread into the mounting for the zincs. Over the course of a season, this mounting hardware is inclined to loosen. Mount the zincs and tighten the mounting hardware securely. Tap the zincs a hammer hitting the mounting screws squarely. This process tightens the zincs and allows the mounting hardware to become a bit loose in the process. Now, do the final tightening. This will insure your zincs stay put for the entire season. All units utilize anodes in at least two locations, many have three. The following list should point you in the right direction for your particular model: a. Cobra-At the bottom of the transom shieldlassembly; on the leading edge of the lower gear case, where it mates with the upperlintermediate unit; and attached to the bearing carrier inside the lower unit. b. SP and King Cobra-At the bottom of the transom shieldlassembly; on the leading edge of the lower gear case, where it mates with the upperlintermediate unit; and, on the aft edge of the lower gear case, just forward of the propeller. c. DP-At the bottom of the transom and, on the leading edge of the lower gear case, where it mates with the upperlintermediate unit. INSPECTION If you use your boat in salt water, and your zincs never wear, them carefully. Paint or wax on zincs prevents them from working properly. They must be left bare. If the zincs are installed properly and not painted or waxed, inspect around them for signs of corrosion. If corrosion found, strip it off immediately and repaint with a rust inhibiting paint. If in doubt, replace the zincs. On the other hand, if your zinc seems to erode in no time at all, this may be a symptom of the zinc itself. Each manufacturer uses a specific blend of metals in their zincs. If you are using zincs with the wrong blend of metals, they may erode more quickly or leave you with diminished protection. Difficulty in starting accounts for almost half of the service required on boats each year. A survey by a major engine parts company indicated that roughly one third of all boat owners experienced a "won't start" condition in a given year. When an engine won't start, most people blame the battery when, in fact, it may be that the battery has run down in a futile attempt to start an engine with other problems. Maintaining your battery in peak condition may be thought of as either tune-up or maintenance material. Most wise boaters will consider it to be both. A complete check up of the electrical system in your boat at the beginning of the boating season is a wise move. Continued regular maintenance of the battery will ensure trouble free starting on the water. Complete battery service procedures are included in this section. The following are a list of basic electrical system service checks that should be performed. Check the battery for solid cable connections Check the battery and cables for signs of corrosion damage Check the battery case for damage or electrolyte leakage Check the electrolyte level in each cell Check to be sure the battery is fastened securely in position Check the battery's state of charge and charge as necessary Check battery voltage while cranking the starter. Voltage should remain above 9.5 volts Clean the battery, terminals and cables ENGINE AND MAINTENANCE 2-49 arrier Fig. 141 Almost all drive units covered here utilize an anode on the leading edge of the unit Fig. 142 Certain models utilize an anode attached to the bearing carrier... Fig. 143 .. . while most models also use one like this, mounted on the bottom of the transom assembly Coat the battery terminals with dielectric grease or terminal protector Check the tension on the alternator belt. Batteries that are not maintained on a regular basis can fall victim to parasitic loads (small current drains which are constantly drawing current from the battery, like clocks, small lights, etc.). Normal parasitic loads may drain a battery on boat that is in storage and not used frequently. Boats that have additional accessories with increased oarasitic load mav discharae a battery sooner. Storing a boat with the negative battery or battery switch turned OFF will minimize discharge due to parasitic loads. CLEANING Keep the battery clean; as a film of dirt can help discharge a that is not used for long periods. A solution of baking soda and water mixed into a paste may be used for cleaning, but be careful to flush this off with clear water. Do not let any of the solution into the filler holes on non-sealed batteries. Baking soda neutralizes battery acid and will de-activate a battery cell. CHECKING SPECIFIC GRAVITY The electrolyte fluid (sulfuric acid solution) contained in the will tell you many things about the condition of the battery. Because the cell plates must be kept submerged below the fluid level in order to operate, maintaining the fluid level is extremely important. In addition, because the specific gravity of the acid is an indication of electrical charge, testing the fluid can be an aid in determining if the battery must be replaced. A battery in a boat with a properly operating charging system should require little maintenance, but careful, periodic inspection should reveal problems before they leave you stranded. Battery electrolyte contains sulfuric acid. If you should splash any on your skin or in your eyes, flush the affected area with plenty of clear water. If it lands in your eyes, get medical help immediately. As stated earlier, the specific gravity of a battery's electrolyte level can be used as an indication of battery charge. At least once a year, check the, specific gravity of the battery. It should be between 1.20 and 1.26 on the gravity scale. Most parts stores carry a variety of inexpensive battery testing hydrometers. These can be used on any non-sealed battery to test the specific gravity in each cell. Conventional Battery SY See Figure 144 A hydrometer is required to check the specific gravity on all that are not maintenance-free. The hydrometer has a squeeze bulb at one end and a nozzle at the other. Battery electrolyte is sucked into the hydrometer until the float or pointer is lifted from its seat. The specific gravity is then read by noting the position of the If gravity is low in one or more cells, the battery should be slowly charged and checked again to see if the gravity has come up. Generally, if after charging, the specific gravity of any two cells varies more than 50 points the battery should be replaced, as it can no longer produce sufficient voltage to guarantee proper operation. Check the battery electrolyte level at least once a month, or more often in hot weather or during periods of extended operation. Electrolyte level can be checked either through the case on translucent batteries or by removing the cell caps on opaque-case types. The electrolyte level in each cell should be kept filled to the split ring inside each cell, or the line marked on the outside of the case. 2-50 ENGINE AND DRIVE MAINTENANCE Never use mineral water or water obtained from a well. The iron content in these types of water is too high and will shorten the life of or damage the battery. If the level is low, add only distilled water through the opening until the level is correct. Each cell is separate from the others, so each must be checked and filled individually. Distilled water should be used, because the chemicals and minerals found in most drinking water are harmful to the battery and could significantly shorten its life. If water is added in freezing weather, the battery should be warmed to allow the water to mix with the electrolyte. Otherwise, the battery could freeze. Maintenance-Free Batteries Although some maintenance-free batteries have removable cell caps for access to the electrolyte, the electrolyte condition and level is usually checked using the built-in hydrometer "eye." The exact type of eye varies between battery manufacturers, but most apply a sticker to the battery itself explaining the possible readings. When in doubt, refer to the battery manufacturer's instructions to interpret battery condition using the built-in hydrometer. The readings from built-in hydrometers may vary, however a green eye usually indicates a properly charged battery with sufficient fluid level. A dark eye is normally an indicator of a battery with sufficient fluid, but one that may be low in charge. In addition, a light or yellow eye is usually an indication that electrolyte supply has dropped below the necessary level for battery (and hydrometer) operation. In this last case, sealed batteries with an insufficient electrolyte level must usually be discarded. BATTERY TERMINALS See Figures 145 and 146 At least once a season, the battery terminals and cable clamps should be cleaned. Loosen the clamps and remove the cables, negative cable first. On batteries with top mounted posts, the use of a puller specially made for this purpose is recommended. These are inexpensive and available in most parts stores. Clean the cable clamps and the battery terminal with a wire brush, until all corrosion, grease, etc., is removed and the metal is shiny. It is especially important to clean the inside of the clamp thoroughly (a wire brush is useful here), since a small deposit of foreign material or oxidation there will prevent a sound electrical connection and inhibit either starting or charging. It is also a good idea to apply some dielectric grease to the terminal, as this will aid in the prevention of corrosion. After the clamps and terminals are clean, reinstall the cables, negative cable last; do not hammer the clamps onto battery posts. Tighten the clamps securely, but do not distort them. To retard corrosion, give the clamps and terminals a thin external coating of clear polyurethane paint after installation. Check the cables at the same time that the terminals are cleaned. If the insulation is cracked or broken, or if its end is frayed, the cable should be replaced with a new one of the same length and gauge. BATTERY CHARGING SAFETY PRECAUTIONS Always follow these safety precautions when charging or handling a battery. Wear eye protection when working around batteries. Batteries contain corrosive acid and produce explosive gas, a byproduct of their operation. Acid on the skin should be neutralized with a solution of baking soda and water made into a paste. In case acid contacts the eyes, flush with clear water and seek medical attention immediately. 2. Avoid flame or sparks that could ignite the hydrogen gas produced by the battery and cause an explosion. Connection and disconnection of cables to battery terminals is one of the most common causes of sparks. Always make sure that your stored battery is no where near any ignition source! 3. Always turn a battery charger OFF, before connecting or disconnecting the leads. When connecting the leads, connect the positive lead first, then the negative lead, to avoid sparks. 4. When lifting a battery, use a battery carrier or lift at opposite corners of the base. 5. Ensure there is good ventilation in a room where the battery is being charged. 6. Do not attempt to charge or load-test a maintenance-free battery when the charge indicator dot is indicating insufficient electrolyte. 7. Disconnect the negative battery cable if the battery is to remain in the boat during the charging process. 8. Be sure the ignition switch is OFF before connecting or turning the charger ON. Sudden power surges can destroy electronic components. 9. Use proper adapters to connect the charger leads to batteries with non-conventional terminals. Fig. 144 The best way to determine the condition of a battery is to test the electrolyte with a battery hydrometer Fig. 145 A battery post cleaner is used to clean the battery posts ... Fig. 146 ...and the battery terminals ENGINE AND DRIVE MAINTENANCE 2-51 BATTERY CHARGERS Before using any battery charger, consult the manufacturer's instructions for its use. Battery chargers are electrical devices that change Alternating Current (AC) to a lower voltage of Direct Current (DC) that can be used to charge a marine battery. There are two types of battery chargers-manual and automatic. A manual battery charger must be physically disconnected when the battery has come to a full charge. If not, the battery can be overcharged, and possibly fail. Excess charging current at the end of the charging cycle will heat the electrolyte, resulting in loss of water and active material, substantially reducing battery life. As a rule, on manual chargers, when the ammeter on the charger registers half the rated amperage of the charger, the battery is fully charged. This can vary, and it is recommended to use a hydrometer to accurately measure state of charge. Automatic battery chargers have an important advantage--they can be left connected (for instance, overnight) without the possibility of overcharging the battery. Automatic chargers are equipped with a sensing device to allow the battery charge to taper off to near zero as the battery becomes fully charged. When charging a low or completely discharged battery, the meter will read close to full rated output. If only partially discharged, the initial reading may be less than full rated output, as the charger responds to the condition of the battery. As the battery continues to charge, the sensing device monitors the state of charge and reduces the charging rate. As the rate of charge tapers to zero amps, the charger will continue to supply a few of current-just enough to maintain a charged condition. REPLACING BATTERY CABLES Battery cables don't go bad very often, but like anything else, wear out. If the cables on your boat are cracked, frayed or broken, they should be replaced. When working on any electrical component, it is always a good idea to disconnect the negative battery cable. This will prevent potential damage to many sensitive electrical components Always replace the battery cables with one of the same length, or you will increase resistance and possibly cause hard starting. Smear the battery posts with a light film of dielectric grease, or a battery terminal protectant spray once you've installed the new cables. If you replace the cables one at a time, you won't mix them up. Any time you disconnect the battery cables, it is recommended that you disconnect the negative (-) battery cable first. This will prevent you from accidentally grounding the positive terminal when disconnecting it, thereby preventing damage to the electrical system. Before you disconnect the first turn the ignition to the OFF position. This will prevent a draw on the battery which could cause arcing. When the battery are reconnected (negative cable last), be sure to check all electrical accessories are all working correctly. STORAGE If the boat is to be laid up for the winter or for more than a few weeks, special attention must be given to the battery to prevent complete discharge or possible damage to the terminals and wiring. Before putting the boat in storage, disconnect and remove the batteries. Clean them thoroughly of any dirt or corrosion and then charge them to full specific gravity reading. After they are fully charged, store them in a clean cool dry place where they will not be damaged or knocked over, preferably on a couple blocks of wood. Storing the battery up off the deck, will permit air to circulate freely around and under the battery and will help to prevent condensation. Never store the battery with anything on top of it or cover the battery in such a manner as to prevent air from circulating around the filler caps. All batteries, both new and old, will discharge during periods of storage, more so if they are hot than if they remain cool. Therefore, the electrolyte level and the specific gravity should be checked at regular intervals. A drop in the specific gravity reading is cause to charge them back to a full reading. In cold climates, care should be exercised in the storaae area. A fully-charged battery will freeze at about 60" zero. A . discharged battery, almost dead, will have ice forming at about above zero. Taking extra time to store the boat properly at the end of each season will increase the chances of satisfactory service at the next season. Remember, storage is the greatest enemy of a marine engine. In a perfect world the unit should be run on a monthly basis. The steering and shifting mechanism should also be worked through complete cycles several times each month. But who lives in a perfect world! For most of a small amount of time is spent in winterizing our beloved boats, the reward will be satisfactory performance, increased longevity and greatly reduced maintenance expenses. Proper winterizing involves adequate protection of the unit from physical damage, rust, corrosion, and dirt. The following steps provide guide to winterizing your marine engine at the end of a season. 1. Always keep a note or a checklist of just what maintenance needs to be done prior to starting the engine in the spring. 2. Replace the oil and oil filter. Normal combustion produces corrosive acids that are absorbed by the oil. Leaving dirty oil in the engine for an extended time allows these acids to attack and damage bearing surfaces. 3. Change the engine oil and filter. Used oil contains harmful acids and contaminants that should not be allowed to go to work on the engine all winter long. The driveltransmission oil should also be changed. 4. Replace the fuel filter elements--draining any water from the filter bowls. 5. Keeping the fuel tank full over the winter will help cut down on condensation. Using fuel additives, like OMC 2t4 Marine Fuel that control bacterial growth or prevent gelling in cold climates are also popular with many boaters and are highly recommended. Be sure to follow the manufacturer's instructions on the side of the can. On models with a carburetor, run the engine under sufficient load to circulate the conditioner through the secondary fuel system. 6. Bleed the fuel system of air and replace the water separating fuel filter. a. Flush the seawater circuit to remove corrosive salts. b. Drain the seawater system, taking special care to empty all the low spots. c. On closed cooling systems, replace the coolant with a clean, fresh, 50150 mixture of water and antifreeze. Always mix the antifreeze and water mixture prior to pouring it into the engine. 7. Inspect all hoses for signs of softening, cracking or bulging, especially those routinely exposed to high heat. Check hose clamps for tightness and corrosion. 8. Close the fuel shut-off valve, if equipped, to stop all flow of fuel from the tanks to the engine. 9. On carbureted engines, remove the flame arrestor and start the engine. Allow it to reach normal operating temperature. Run the engine at fast idle and squirt about 213 of an 8 oz. of can of Storage Fogging Oil or 12 oz. (355 ml) spray into the carburetor or throttle body. Just as the engine is starting to sputter, squirt the remaining 113 of the container into the carblthrottle body and allow the engine to die. Install the flame arrestor. 10. On EFI engines, purchase a 6 gallon external fuel tank for an outboard. Add 5 gallons of fuel, 4 pints (64 oz.) of OMC Storage Fogging Oil and 113 cup (2.5 oz.) of Marine Fuel Conditioner-mix thoroughly, and carefully. Carefully disconnect and plug the main fuel line from the boats fuel tank at the fuel pump. Hook a line from the 6 gallon fuel tank to the pump. Start the engine (using the fogging mixture as the fuel source) and run it at 1500 rpm for 5 minutes to ensure that all fuel system and internal engine components are completely coated and protected. Turn off the engine and reinstall the main fuel line. 2-52 ENGINE AND DRIVE MAINTENANCE 11. It's also a good idea to remove the spark plugs and pour about an ounce of Fogging Oil into each cylinder. You can also use SAE 20 motor oil. Crank the engine with the starter for a few seconds to make sure that the oil coats the cylinder bores completely. 12. On engines so equipped, remove the water separating fuel filter and pour in about 2 oz. of 2 cycle outboard oil. Reinstall the filter, start the engine and run it until it dies. Install a new filter. 13. Perform all the lubrication procedures detailed in this section. 14. Loosen the adjusting bolts or tensioners on all drive or serpentine belts until the tension is relieved. 15. Fully charge the batteries. Disconnect all leads. Unattended, a battery naturally discharges over a period of several weeks. The electrolyte on a discharged battery can freeze at 20F so keep the batteries fully charged or, better still, remove them to a warmer storage area. Small automatic trickle chargers work well. 16. Treat battery and cable terminals with petroleum jelly, silicone grease, or a heavy-duty corrosion inhibitor. 17. Protect external surfaces with a heavy-duty corrosion inhibitor. 18. Grease all greaseable points on the drivetrain. 19. Lightly coat the alternator and starter with a light lubricant to disperse the water. 20. Ensure that all drain holes on the stern drive are open by inserting a piece of wire into them. 21. Make sure the stern drive is in the full position. 22. Cover the engine with a waterproof sheet in case there are any leaks from above. Some boaters will take the time to seal all openings to the engine (air inlet, breathers, exhaust), however this traps moisture and may do more harm than good. Place a checklist in a handy spot to remind you of just what maintenance needs to be done prior to starting the engine in the spring. If this sounds silly, DO IT ANYWAY!! 24. If you visit the boat during the winter, additional protection can be achieved using the starter to turn the engine over and circulate oil to the bearings and cylinder walls. 25. the boat is to be stored out of the water, always remove the drain if equipped. We suggest you attach the plug to the ignition key as added insurance that you remember to reinstall it in the spring sound silly? Why take the chance! Special inhibiting oils are available that provide greater protection. Use these to replace the standard engine oil; run the engine briefly to coat all surfaces, and then drain the oil. Protection remains good, provided the engine is not turned. 26. If the engine cannot be fully winterized, replace oil, coolant, and all filters and run the engine up to operating temperatures monthly. Satisfactory performance and maximum enjoyment can be realized if a little time is spent in commissioning your boat in the spring. Assuming you have followed the steps we recommended to winterize your vessel (in addition to any the manufacturer specifies) and the unit has been properly stored, a minimum amount of work should be required to prepare it for use. After performing the spring commissioning and testing the boat on the water, it is a good idea to perform a full tune-up. Remember, you are relying on your engine to get you where you want to go. Treat it good now and it will treat you good later. The following steps outline a logical sequence of tasks to be performed before starting your engine for the first time in a new season. Pick up the checklist you made to remind yourself of just what maintenance needs to be done prior to startinq the engine in the spring. You . did remember to write yourself a checklist....right? 2. INSTALL THE DRAIN PLUG IF REMOVED! 3. Remove the cover placed over the engine last winter. Unseal any engine openings (air inlet, breathers, exhaust) previously sealed. 4. Replace all zincs. 5. you took our advice, you removed the battery for the winter. While it was in storage, you should have kept it fully charged. It should be ready to go, So install the battery and connect the battery cables. Treat battery and cable terminals with petroleum jelly, silicone grease, or a heavy-duty corrosion inhibitor. Capacity test the batteries. 6. Tighten the alternator and other belts. 7. As you did in the winter, inspect all hoses for signs of softening, cracking or bulging, especially those routinely exposed to high heat. Check hose clamps for tightness and corrosion. 8. Ensure the exhaust manifolds are tight. 9. On closed system engines, check the condition of the coolant mixture with a coolant tester and adjust the mixture by adding antifreeze or water. 10. Bleed the fuel system of air. 11. Connect the spark plug wires and any other connections. 12. Start the engine and allow it to reach operating temperature. Once running, check the oil pressure, the raw water discharge and the engine for oil and water leaks. 14. Drain water from the filter bowls. If an excessive amount of water is noted in the fuel system, you may want to consider a fuel conditioner or replacing the old fuel with fresh fuel. 15. After testing the boat on the water, it is a good idea to change the engine oil and filter. The driveltransmission oil should also be changed. This eliminates the adverse effects of moisture in the oil. See Figures 147 thru 156 To avoid confusion, ALWAYS label the spark plug wires with a piece of tape before disconnecting them from the plug or distributor cap. Front Fig. 148 Firing order diagram--4.31 V6 engines clockwise) I I Fig. 147 Firing order 4 cylinder engines Fig. 149 Firing order and Front ENGINE AND DRIVE MAINTENANCE 2-53 Fig. 151 Firing order and GM V8 engines clockwise) Front 4 cylinder engines (1-3-4-2, clockwise) Fig. 152 Firing order diagram-350,454 and 502 GM V8 engines (1-8-4-3-6-5-7-2, clockwise) Fig. 150 Firing order diagram-4.31 HO V6 engines (1-6-5-4-3-2, clockwise) 2-54 ENGINE AND DRIVE MAINTENANCE Fig. 153 Firing order diagram-5.01 (1986-93) and Ford V8 engines counterclockwise) Fig. 156 Firing order diagram--460 Ford V8 engines counterclockwise) Fig. 155 Firing order and 351 Ford V8 engines (1-3-7-2-6-5-4-8, counterclockwise) Fig. 154 Firing order diagram-5.01 HO and Ford V8 engines (1-3-7-2-6-5-4-8, counterclockwise) Engine Model Applications Applications-1986-89 ENGINE MODEL APPLICATIONS Model Displacement Engine Horsepower Fuel Stern Year Model Number In. Type (At Prop.) 1986 25 L4 NA 2 bbl Cobra 3 0 3.01181 L4 NA 2 bbl Cobra 4.3 4.31262 NA 2 bbl Cobra V6 NA 4 bbl Cobra 5.0 5.01305 4 bbl Cobra 5.7 5.71350 230 4 bbl Cobra 1987 2.3 2.31140 L4 N A 2 Cobra 3 0 3 011 81 L4 NA 2 bbl Cobra 4.3 4.31262 N A 2 bbl Cobra NA 4 bbl Cobra 5.0 5.01305 185 4 bbl Cobra 5.7 230 4 bbl Cobra 7.5 V8 335 4 bbl Cobra 440 Cobra 1988 2.3 2.31140 L4 NA 2 bbl Cobra 3 01181 L4 NA 2 bbl Cobra N A 2 bbl Cobra . 4 31262 NA 4 bbl Cobra 5.0 5.01305 NA 2 bbl CobraI 57 4 bbl Cobra 5.71350 230 4 bbl Cobra NA Not Available Engine Model Applications Applications-1990-92 ENGINE MODEL APPLICATIONS Model Engine Horsepower Fuel Stern 3.0 HO L4 NA 2 bbl Cobra , 4.3 2 bbl Cobra 4.3 HO 4.31262 V6 NA 4 bbl Cobra 5.0 V8 2 bbl Cobra 5.0 HO 200 2 bbl Cobra 5 7 5.71350 V8 230 4 bbl Cobra 5.7 LE NA 4 bbl Cobra 5.8 235 4 bbl Cobra 350 NA 4 bbl Cobra 454 7.41454 NA 4 bbl King Cobra 460 NA 4 bbl King Cobra 991 3.0 3.01181 L4 120 2 bbl Cobra 3.0 HO L4 NA 2 bbl Cobra 4.3 V6 160 2 bbl Cobra 4.3 HO V6 NA 4 bbl Cobra 5.0 5.01302 V8 185 2 bbl Cobra 5.0 HO 5.01302 200 2 bbl Cobra 5.7 230 4 bbl Cobra 5.7 LE, 350 5.71350 NA 4 bbl King Cobra 5.8 5 235 4 bbl Cobra 454. V8 300 4 bbl Cobra . . .. . , , . . . . 3.0 3.01181 L4 120 2 bbl Cobra 3.0 3.01181 L4 NA 2 bbl Cobra 4.3 160 2 bbl Cobra 5.0 5.01302 185 2 bbl Cobra 5.0 HO 200 2 bbl Cobra 5.7 230 4 bbl Cobra 5.7 LE 4 bbl King Cobra 5.8 V8 235 4 bbl Cobra 5.8 LE, 351 5.81351 V8 235 4 bbl King Cobra 454, V8 4 bbl Cobra 454 HO 502 8.2502 V8 390 4 bbl King Cobra Engine Model Applications Applications--1993-96 ENGINE MODEL APPLICATIONS Model Displacement Horsepower Fuel Stern Year Model Number In. Type (At Prop.) Delivery Drive 1993 3.0 3.01181 L4 120 2 bbl Cobra 3.0 HO 3.01181 L4 130 2 bbl Cobra 4.3 160 2 bbl Cobra 4 3 HO N A 2 bbl Cobra 5 0 5 01302 185 2 Cobra 5 0 HO 5 2 bbl Cobra 5 0 EFI 5 01302 21 5 EFI Cobra 5 8 5 81351 235 4 bbl Cobra 5 8 EFI 5 81351 240 EFI Cobra 5.8 LE, 351 N A 4 bbl King Cobra EFI King Cobra 7 4GL 7.41454 3W 4 bbl King Cobra 454 HO 8 502 390 4 bbl Cobra 1994 3 3 01181 L4 120 2 bbl Cobra 3 3 01181 L4 135 2 Cobra 4 3GL 4 160 2 bbl Cobra MPI Mum-Port TBI Throttle Body DP NA Not Available Engine Model Applications Applications-1997-98 ENGINE MODEL APPLICATIONS Model Displacement Engine Horsepower Fuel Stern EFI Fuel Injection Injection Throttle Body Prop DP NA Not TUNE-UP SPECIFICATIONS 1986-88 Ignition Fuel Spark Plug Timing Speed Max. Point Pressure Compression Gap . BTDC Rpm WOT Mixture Dwell Pressure Year Model Champion AC (mm) rpm) (rpm) (Turns Out) In. (Deg.) 1986 2.5 RV8-C 0.035 (0.9) 500-600 4200-4600 2 0.019 (0.48) 32-34 130 3.0 RV8-C 0.035 (0.9) 500-600 4200-4600 2 32-34 130 NA Not adjustable & 8 BTDC AKI octane; 13 BTDC AKI octane 1 ATDC AKI octane; 4 BTDC AKI octane & 5 BTDC AKI octane; 10 BTDC AKI octane BTDC AKI octane; 6 BTDC AKI octane 5 BTDC AKI octane; 10 BTDC octane 8 BTDC AKI octane; 13 BTDC AKI octane 3 BTDC AKI octane; 8 BTDC AKI octane 5 BTDC octane, 10 BTDC AKI octane 10 BTDC AKI octane; 15 BTDC AKI octane Motorcraft 8 3 BTDC AKI octane; 8 BTDC AKI octane 2 112, 4 bbl: 3 314 TUNE-UP SPECIFICATIONS 1989-90 Ignition Fuel Spark Plug Timing Speed Max. Point Pressure Compression Gar, . WOT Mixture Dwell Pressure Year Model Champion AC In. (mm) rpm) (In (Turns Out) In. (mm) (Deg.) 1989 2.3 AWSF-32 0.035 (0.9) 600-650 5200-5600 1 0.01 9 (0.48) 34-38 5.75-7 155-1 65 550-600 4200-4600 2 0.019 (0.48) 31-34 130 3.0 RV8-C 0.035 (0.9) 4.3 RV8-C 0.035 (0.9) 550-600 4200-4600 518 0.019 (0.48) 37-41 5.75-7 160-1 75 4.3 RV8-C 0.035 (0.9) 550-600 4400-4800 1 0.019 (0.48) 37-41 5.75-7 160-1 75 5.0 0.035 (0.9) 550-600 4000-4400 1 0.01 8 (0.45) 27-31 5.75-7 145-1 55 5.7 RV8-C 0.035 (0.9) 8 550-600 4200-4600 3 314 8 (0.45) 27-31 5.75-7 150-1 60 5.8 0.035 (0.9) 550-600 4000-4400 1 0.018 (0.45) 27-31 5.75-7 145-1 55 262 0.035 (0.9) 550-600 4400-4800 1 0.01 9 (0.48) 37-41 5.75-7 160-1 75 350 RV8-C 0.035 (0.9) 8 550-600 4200-4600 3 314 0.018 (0.45) 27-31 5.75-7 150-1 60 460 ASF-32M 0.035 (0.9) 600-650 4400-4800 0.01 8 (0.45) 27-31 5-6 155-1 65 1990 2.3 RSI 2YC AWSF-32 0.035 (0.9) 600-650 5200-5600 1 0.01 9 (0.48) 34-38 5.75-7 75% of Highest 30 HO 0.035 550-600 4200-4600 1 (Starboard) NA NA 5.75-7 75% of Highest 1 (Port) 3.0 NA NA 5.75-7 75% of Hi . , - 4.3 RV8-C 0.035 (0.9) 550-600 4200-4600 0.019 (0.48) 37-41 5.75-7 75% of Highest 4.3 HO 0.035 (0.9) N A 550-600 4400-4800 314 N A NA 5.75-7 75% of Highest 5.0 HO RV8-C 0.030 (0.76) 10 550-600 4200-4600 1 0.01 8 (0.45) 27-31 5.75-7 75% of Highest 57 0.035 (0.9) 8 550-600 4200-4600 1 0.018 (0.45) 27-31 5.75-7 75% of Highest 5.7 LE RV8-C 0.035 (0.9) 8 500-600 4200-4600 1 0.018 (0.45) 27-31 5.75-7 60 5.8 RV8-C 0.030 (0.76) 550-600 4200-4600 1 0.01 8 (0.45) 27-31 5.75-7 75% of Highest 350 0.035 (0.9) N A 500-600 4200-4600 1 NA NA 5.75-7 60 454 RV8-C 0.035 (0.9) NA 500-600 4600-5000 1 NA NA 5 75-7 150-1 60 460 0.035 (0.9) NA 600-650 4400-4800 1 N A NA 5-6 65 NA Not adjustable 5 BTDC AKI 10 BTDC AKI 1 ATDC AKI octane; 4 BTDC AKI octane 3 BTDC AKI 8 BTDC AKI 1 BTDC AKI octane; 6 BTDC AKI octane 10 BTDC AKI octane; 15 BTDC AKI octane Motorcraft PWS: PWC: 8 BTDC AKI 13 BTDC AKI Shunt required 5 BTDC AKI 10 BTDC AKI 3 BTDC AKI octane; 8 BTDC AKI octane TUNE-UP Ignition Distributor Oil Fuel Spark Plug Timing Speed Max. Sensor Pressure Pressure Compression Gap (Deg. BTDC Rprn WOT Air Gap Mixture 2000 rpm Pressure Year Model Champion AC In. (rnm) (In Gear) (rpm) In. (mm) (Turns Out) (psi) 1991 3.0 0.045 (1.1 4) 0 650-750 NA 314 40-60 5.757 75% of Highest 3.0 HO 0.045 (1.14) 0 650-750 NA 1 (Starboard) 40-60 5.757 75% of Highest (Port) 4.3 0.035 (0.9) 550-650 4200-4600 0.008 (0.203) 40-60 5.757 75% of Highest 4.3 HO 0.045 (1.14) NA 550-650 4400-4800 NA 40-60 5.75-7 75% of Highest 5.0 0.035 (0.9) 550-650 4000-4400 0.008 (0.203) 1 118 5.75-7 75% of Highest 5.0 HO 0.035 (0.9) 10 550-650 4000-4400 0.008 (0.203) 1 40-60 5.75-7 75% of Highest 5.7 0.035 (0.9) 550-650 4200-4600 0.008 (0.203) 1 40-60 5.75-7 75% of Highest 5.7 LE 0.035 (0.9) 550-650 0.008 (0.203) 1 40-60 5.75-7 75% of Highest 5.8 0.035 (0.9) 10 4000-4400 0.008 (0.203) 40-60 5.757 75% of Highest 350 RV8-C 0.045 (1.14) N A 4200-4600 NA 1 40-60 5.75-7 75% of Highest 454 0.045 (1.14) NA 550-650 4000-4400 NA 1 40-60 5.757 75% of Highest 454HO 0.045 (1.14) NA 550-650 4600-5000 NA 114 40-60 5.75-7 75% of Highest 1992 3.0 0.045 (1.1 4) 0 650-750 4200-4600 N A 314 40-60 5.75-7 75% of Highest 3.0 HO 0.045 , 0 650-750 4200-4600 NA 1 (Starboard) 112 (Port) 40-60 5.75-7 75% of Highest 4.3 5.0 5.0 HO RV8-C 0.035 (0.9) 0.035 (0.9) 0.035 (0.9) 10 10 550-650 550-650 550-650 4200-4600 4000-4400 4000-4400 0.008 (0.203) (0.203) 0.008 (0.203) 518 1 118 1 40-60 40-60 40-60 5.75-7 5.75-7 5.75-7 75% of Highest 75% of Highest 75% of Highest 5.7 5.7 LE RV8-C 0.035 (0.9) 0.035 (0.9) 550-650 550-650 4200-4600 4200-4600 0.008 (0.203) 0.008 (0.203) 114 1 40-60 5.75-7 5.75-7 75% of Highest 75% of Highest . 5.8 0.035 (0.9) 10 550-650 4000-4400 0.008 (0.203) 718 40-60 5.757 75% of Highest 5.8 LE, 351 0.045 (1.14) NA 4600-5000 NA 718 40-60 5.75-7 75% of Highest 454 RV8-C 0.045 (1.14) N A 550-650 4200-4600 N A 1 40-60 5.75-7 75% of Highest 454 HO RV8-C 0.045 (1.14) NA 550-650 4600-5000 NA 1 40-60 5.757 75% of Highest 0.045 (1.14) NA 550-650 4800-5200 N A 1 40-60 5.75-7 75% of Highest NA Not adjustable Shunt required 1 BTDC AKI octane; 6 BTDC AKI octane 3 BTDC AKI octane; 8 BTDC AKI octane TUNE-UP SPECIFICATIONS 1993-94 Ignition Distributor Oil Fuel Spark Plug Timing Speed Max. Sensor Pressure Pressure Compression Gap (Deg. BTDC WOT Air Gap Mixture 2000 rpm Pressure Year Model Volvo Champion In. rpm) (In Gear) (rprn) In. (Turns Out) (psi) 1993 3.0 0.045 (1 0 650-750 4200-4600 N A 314 40-60 75% of Highest 3.0 HO 0.045 0 650-750 4200-4600 NA 1 (Starboard) 40-60 75% of Highest 112 (Port) 4.3 RV8-C 0.035 (0.9) 550-650 0.008 (0.203) 518 40-60 75% of Highest 4.3 HO 0.035 (0.9) 550-650 4200-4600 0.008 (0.203) 40-60 5.75-7 75% of Highest 5.0 0.035 (0.9) 10 4000-4400 0.008 (0.203) NA 40-60 75% of Highest -5.75-7 75% of Highest 5.0 EFI RV8-C 0.045 (1 4) 5 N A 1 40-60 5.75-7 75% of Highest 5.8 0.035 (0.9) 550-650 4000-4400 0.008 (0.203) 40-60 5.75-7 75% of Highest 5.8 EFI RXZCLTS 0.045 (1.14) 5 4200-4600 N A N A 40-60 75% of Highest 5.8 LE, 351 0.045 (1 4) 10 550-650 4600-5000 N A 40-60 5.75-7 75% of Highest 454 RV8-C 0.045 (1 4) 10 550-650 N A 1 40-60 75% of Highest 454 HO M 0.045 (1 4) 10 550-650 N A 1 40-60 5.75-7 75% of Highest 502 RV8-C 0.045 (1.14) 550-650 N A 1 40-60 5.75-7 75% of Highest 1994 0.045 (1 4) 0 4200-4600 N A 40-60 75% of Highest 0.045 (1 4) 0 650-750 4200-4600 NA (Starboard) 40-60 5.75-7 75% of Highest 112 (Port) 0.045 (1.14) 0 550-650 4200-4600 NA 518 40-60 5.75-7 75% of Highest 0.045 (1.14) 5 600 4200-4600 N A NA 40-60 31-39 75% of Highest 0.035 (0.9) 550-650 4200-4600 0.008 (0.203) 1 40-60 75% of Highest 0.035 (0.9) 550-650 4200-4600 0.008 (0.203) 40-60 5.75-7 75% of Highest 0.045 (1.14) 5 600 4200-4600 N A N A 40-60 31-39 75% of Highest 0.035 (0.9) 10 550-650 4000-4400 0.008 (0.203) 40-60 75% of Highest 351 EFI 0.045 (1.1'4) 5 4600-5000 NA NA 31-39 75% of Highest 0.045 (1 550-650 4200-4600 NA 1 40-60 5.75-7 75% of Highest NA Not adjustable Shunt required 1 BTDC AKI octane; 6 BTDC AKI octane 3 BTDC AKI octane; 8 BTDC AKI octane Fixed Not adjustable TUNE-UP 1995-96 Ignition Distributor Oil Fuel Spark Plug Timing Speed Max. Sensor Pressure Pressure Compression Gap (Deg. BTDC Rpm WOT Air Gap Mixture 2000 Pressure Year Model Volvo Champion In. rpm) (In Gear) (rpm) In. (Turns Out) (psi) 1995 0.045 (1.1 4) 0 650-750 4200-4600 NA 1 (Starboard) 40-60 5.75-7 75% of Highest 1 12 (Port) 0.045 (1 14) 550-650 42004600 N A 518 40-60 5.75-7 75% of Highest 5.0 EFI 0.045 5 600 4200-4600 N A NA 40-60 31-39 75% of Highest 0.035 (0.9) 550-650 4400-4800 0.008 (0.203) 1 40-60 75% of Highest 5.8 0.045 (1.14) 5 600 4200-4600 NA N A 40-60 31-39 75% of Highest 0.035 (0.9) 10 550-650 4000-4400 0 008 (0 203) 40-60 5.75-7 75% of Highest 5.8 HO EFI 0.045 (1 5 600 4600-5000 N A N A 40-60 31-39 75% of Highest 0.045 (1.14) 10 550-650 4200-4600 N A 1 40-60 5.75-7 75% of Highest 7.4 EFI 0.045 (1.1 4) 4800-5200 N A N A 40-60 31-39 75% of Highest 0.045 (1.1 4) 0 650-750 4200-4600 NA 1 (Starboard) 40-60 5 75-7 75% of Highest Not adjustable Shunt required 5 BTDC AKI octane; TDC AKI octane; shunt Not adjustable Diagnostic leads shorted TUNE-UP 1997-98 Ignition Distributor Oil Fuel Spark Plug Timing Speed Max. Sensor Pressure Pressure Compression Gap BTDC Rpm WOT Air Gap Mixture 2000 rpm Pressure Year Model Volvo Champion In. (mm) rpm) (In Gear) (rpm) In. (mm) (Turns Out) (psi) 1997 4200-4600 NA I(Starboard) 40-60 5-7 75% of Highest (Port) 0.045 (1.14) 0 0.045 (1.14) 8 6000 4400-4800 NA NA 40-60 31-39 75% of Highest 40-60 5-7 75% of Highest 0.045 (1 550-650 4200-4600 N A 0.045 (1.14) 550-650 N A 314 40-60 5-7 75% of Highest 6000 N A N A 40-60 31-39 75% of Highest 0.045(1.14) 8 40-60 5-7 75% of Highest 0.035 (0.9) 550-650 4200-4600 0.008 (0.203) 40-60 5-7 75% of Highest 0.035 (0.9) 550-650 4200-4600 0.008 (0.203) 0.045 (1.14) 8 600 4600-5000 N A N A 40-60 31-39 75% of Highest 0.045 (1 4) 10 4200-4600 N A N A 40-60 31-39 75% of Highest 0.045 (1.14) 550-650 4200-4600 N A 1 40-60 5-7 75% of Highest 0.045 (1 4) 0 650-750 4200-4600 NA 1 (Starboard) 40-60 5-7 75% of Highest (Port) N A NA 40-60 31-39 75% of Highest 0.045 (1.14) 8 600 40-60 5-7 75% of Highest 0.045 (1.14) 4200-4600 N A 40-60 5-7 75% of Highest 0.045 (1.14) 550-650 4400-4800 NA 1 40-60 5-7 75% of Highest 0.035 (0.89) 4400-4800 0.008 (0.203) 40-60 5-7 75% of Highest 6000 4600-5000 N A NA 40-60 31-39 75% of Highest 0.035 (0.89) 0.008 (0.203) N A NA 40-60 31-39 75% of Highest 0.045 (1 10 0.045 (1.14) 10 4800-5200 NA N A 40-60 31-39 75% of Highest 0.045 (1 4) 4600-5000 NA N A 40-60 31-39 75% of Highest 1 BTDC AKI octane; 6 BTDC AKI octane; shunt req'd NA Not adjustable 3 BTDC AKI octane; 8 BTDC AKI octane Shunt required Diagnostic leads shorted 5 BTDC AKI octane; 10 BTDC AKI octane 7 BTDC AKI octane; 12 BTDC AKI octane Not adjustable CAPACITIES CAPACITIES Crankcase Stern Drive Power Trim Crankcase Stern Drive Power Trim (With Filter) (ml) Reservoir Year Model Cobra King Cobra SP DP 1992 3.0, 3.0 HO 4.0 (3.8) 64 (1892) X X X 54 (1597) 4.3 4.5 (4.3) 64 (1892) X X X 54 (1597) 5.0, 5.0 HO 6.0 (5.7) 64 (1892) X X X 54 (1597) 5.7, 5.8 6.0 (5.7) 64 (1892) X X X 54 (1597) 5.7 LE, 351 6.0 (5.7) X 103 (3050) X X 54 (1597) 454 454 HO 7 0 X 103 X X ..., ..... ,.. . .. . ,. ., 1993 3.0, 3.0 HO 4.0 (3.8) 64 (1892) X X X 54 (1597) 4.3. 4.3 HO 4.5 (4.3) 64 (1892) X X X 54 (1597) X X X 54 (1597) 5.8, 5.8 EFI 5.0 (4.7) 64 (1892) X X X 54 (1597) 5.8 LE. 351 5.0 (4.7) X 103 (3050) X X 54 (1597) 454, 454 HO, 502 7.0 (6.6) X 103 (3050) X X 54 (1597) 1994 4.0 (3.8) 71 (2100) X X X 54 (1597) 4.5 (4.3) 71 (2100) X X X 54 (1597) 6.0 (5.7) 71 (2100) X X X 54 (1597) 5.0 (4.7) 71 (2100) X X X 54 (1597) 6.0 (5.7) 71 (2100) X X X 54 (1597) 7.0 (6.6) X 103 (3050) X 351 EFI 5.0 (4.7) X 103 (3050) X X 54 (1597) X 54 (1597) 4.0 (3.8) 71 (2100) X X X 54 (1597) 4.5 (4.3) 71 (2100) X X X 54 (1597) 6.0 (5.7) 71 (2100) X X 5.0 EFI 6.0 (5.7) 71 (2100) X X X 54 (1597) X 54 (1597) 5.8 EFI, 5.8 HO EFI 5.0 (4.7) 71 (2100) X X X 54 (1597) 7.4 EFI 7.0 (6.6) X 103 (3050) X X 54 (1597) 1996 4.0 (3.8) X X 71 (2100) 54 (1597) X X 71 (2100) 81 (2400) 54 (1597) 6.0 (5.7) X X 71 (2100) 81 (2400) 54 (1 597) 6.0 (5.7) X X 71 (2100) 81 (2400) 54 (1597) 6.0 (5.7) X X 71 (2100) 81 (2400) 54 (1597) 5.0 (4.7) X X 71 (2100) 81 (2400) 54 (1597) 9.0 (8.5) X X 71 (2100) 81 (2400) 54 (1 597) 7.0 (6.6) X X 71 (2100) 81 (2400) 54 (1 597) 1997 4.0 (3.8) X X 71 (2100) X 54 (1597) 4.5 (4.3) X X 71 (2100) 81 (2400) 54 (1 597) 5.7 GS 6.0 (5.7) X X 71 (2100) 81 (2400) 54 (1597) 6.0 (5.7) X X 71 (2100) 81 (2400) 54 (1597) 9.0 (8.5) X X 71 (2100) 81 (2400) 54 (1597) 4.0 (3.8) X 71 (2100) X 54 (1597) 4.5 (4.3) X X 71 (2100) 81 (2400) 54 (1597) 6.0 (5.7) X X 71 (2100) 81 (2400) 54 (1597) 5.7 6.0 (5.7) X X 71 (2100) 81 (2400) 54 (1597) 9.0 (8.5) X X 71 (2100) 81 (2400) 54 (1597) 9.0 (8.5) X X X 81 (2400) 54 (1597) All capacities are approximate. Always use the dipstick or hole to determine the exact quantity Although badged as King Cobras, the 262 and 350 are actually Cobras of lubricant required. 2-64 ENGINE AND MAINTENANCE MAINTENANCE INTERVALS Before SO 100 SO 100 Once A Component Procedure Use Weekly 25 Hrs. Days Days Days Season Season Season Anodes Inspect X Battery Check Fluid Level X Inspect X Bilge Inspect X Carburetor X Cooling System Check Level Closed System X Check Pressure Cap X Flush Sea Water X X lnspect Hoses Clamps: X Saltwater X Replace Coolant X Drive Belts Inspect X Electrical System Check Wiring: X Saltwater X Engine Alignment Check X Flame Arrestor Cleanllnspect 1986-90 X 1991-98 X Fuel Filter Replace X Fuel Pump -Check Vent Mechanical Tube X ENGINE AND DRIVE MAINTENANCE 2-65 MAINTENANCE INTERVALS Before SO SO 100 SO 100 Once A Component Procedure Use Weekly 25 Hrs. Days Days Days Season Season Season Fuel System Svstem X Replace Filter X Fuel Tank Check For Water x Gimbal Bearing Lubricate X Ignition System X Adjust X Oil Check Level: Crankcase X Power Steerina X Stern Drive X Trim Pump X Change: Crankcase X Power Steering X Stern Drive X Trim Pump X Oil Filter Change X PCV Valve X Cable Lubricate: Freshwater X Saltwater X Pluas Check X.. X Spark Plug Wires Inspect X Steering System Check Fluid Level X 2-66 ENGINE AND DRIVE MAINTENANCE MAINTENANCE INTERVALS Before Once A Component Procedure Use Weekly 25 Hrs. Days Days Days Season Season Season Stern Drive Check Water Pick-up X Oil Check Level X Replace X Transom Inspect X Pump Inspect X Check Fluid Level X Grease X Lube Splines X ENGINE AND DRIVE MAINTENANCE 2-67 -68 ENGINE AND MAINTENANCE AUXILIARY SHAFT ................... REMOVAL INSTALLATION CAMSHAFT REMOVAL INSTALLATION CYLINDER HEAD .................... REMOVAL INSTALLATION CYLINDER HEAD (CAMSHAFT) COVER . . REMOVAL INSTALLATION ENGINE COUPLER AND FLYWHEEL REMOVAL INSTALLATION ENGINE IDENTIFICATION MODEL DESIGNATIONS ENGINE REMOVAL INSTALLATION ENGINE ALIGNMENT ............... ENGINE MECHANICAL AUXILIARY SHAFT ................. CAMSHAFT CYLINDER HEAD CYLINDER HEAD (CAMSHAFT) COVER . ENGINE ENGINE COUPLER AND FLYWHEEL ... ENGINE IDENTIFICATION EXHAUST HOSE (BELLOWS) EXHAUST MANIFOLD ............... EXHAUST .................... FRONT COVER .................... FRONT ENGINE MOUNTS FRONT OIL SEALS ................. GENERAL INFORMATION HIGH-RISE EXHAUST ELBOW INTAKE MANIFOLD ................. OIL PAN OIL PUMP ........................ REAR ENGINE MOUNTS REAR OIL SEAL ............... ROCKER ARMS AND HYDRAULIC ADJUSTERS TIMING BELT AND TIMING SPROCKETS EXHAUST HOSE (BELLOWS) REMOVAL INSTALLATION .......... EXHAUST MANIFOLD ................ REMOVAL INSTALLATION .......... EXHAUST ..................... REMOVAL INSTALLATION .......... EXHAUST VALVE (FLAPPER) .......... REPLACEMENT .................... FRONT COVER ..................... REMOVAL INSTALLATION .......... FRONT ENGINE MOUNTS ............. REMOVAL INSTALLATION .......... HIGH-RISE EXHAUST ELBOW ......... REMOVAL INSTALLATION .......... INTAKE MANIFOLD .................. REMOVAL INSTALLATION .......... OIL PAN REMOVAL INSTALLATION .......... OIL PUMP DISASSEMBLY ASSEMBLY REMOVAL INSTALLATION .......... REAR ENGINE MOUNTS REMOVAL INSTALLATION REAR OIL SEAL ................ REMOVAL INSTALLATION .......... ROCKER ARMS HYDRAULIC ADJUSTERS REMOVAL INSTALLATION .......... VALVE ADJUSTMENT ............... VALVE ADJUSTMENT ................ FRONT COVER ..................... REMOVAL INSTALLATION .......... SPECIFICATIONS ................... ENGINE TORQUE TIMING BELT AND CHECKING CORRECTING AN OUT-OF-TIME ENGINE REMOVAL INSTALLATION TlMlNG SPROCKETS ................ REMOVAL INSTALLATION .......... ENGINE MECHANICAL -FORD 4 CYLINDER ENGINES The OMC 140 cubic inch displacement engine is manufactured by Ford and has been a favorite combination when mated to the OMC Cobra stern drives. This in-line four-cylinder overhead camshaft power plant uses a full pressure lubrication system with a disposable flow-thru oil filter cartridge. Oil pressure is furnished by a gear-type oil pump, driven by the auxiliary shaft, which is driven, via the timing belt, by the crankshaft. A regulator on the oil pump controls the amount of oil pressure output. The oil pump scavenges oil from the bottom of the oil pan and feeds it through the oil filter and then to the main oil gallery in the block. Drilled passages in the block and crankshaft distribute oil to the camshaft and crankshaft to lubricate the rod, main and camshaft bearings. The camshaft runs in 4 bearings and is driven by the crankshaft via the timing belt. The auxiliary shaft, also driven by the crankshaft via the timing belt, drives the fuel pump and distributor in addition to the oil pump. The crankshaft runs in 5 main bearings with the middle bearing providing thrust. Cylinder numbering and firing orders are identified in the illustrations at the end of the Maintenance section. NEVER, NEVER attempt to use standard automotive parts when replacing anything on your engine. Due to the uniqueness of the environment in which they are operated in, and the levels at which they are operated at, marine engines require different versions of the same part; even if they look the same. Stock and most aftermarket automotive parts will not hold up for prolonged periods of time under such conditions. Automotive parts may appear identical to marine parts, but be assured, OMC marine parts are specially manufactured to meet OMC marine specifications. Most marine items are super heavy- duty units or are made from special metal alloy to combat against a corrosive salt water atmosphere. OMC marine electrical and ignition parts are extremely critical. the United States, all electrical and ignition parts manufactured for marine application must conform to stringent Coast Guard requirements for spark or flame suppression. A spark from a non-marine cranking motor solenoid could ignite an explosive atmosphere of gasoline vapors in an enclosed engine compartment. ENGINE + See Figure 1 The engine serial numbers are the manufacturer's key to engine changes. These alpha-numeric codes identify the year of manufacture, the horsepower rating and various differences. If any correspondence or parts are required, the engine serial number must be used for proper identification. Remember that the serial number establishes the year in which the engine was produced, which is often not the year of first installation. The engine specifications contains information such as the number or code, the serial number (a unique sequential identifier given ONLY to that one engine) as well as other useful information. An engine specifications decal can generally be found on top of the flame arrestor or on the side of the rocker arm cover all pertinent serial number information can be found here--engine and drive designations, serial numbers and model numbers. Unfortunately this decal is not always legible on older boats and it's also quite difficult to find, so please refer to the following procedures for each individuals unit's serial number location. Serial numbers tags are frequently difficult to see when the engine is installed in the boat; a mirror can be a handy way to read all the numbers. The engine number is sometimes also stamped on the port rear side of the engine where it attaches to the bell housing; although on most later models it may instead be a metal plate attached in the same location. If your engine has a stamped number it will simply be the serial number; if you have a plate (and you should), it will always show a Model number and then the actual Serial number. Additionally, most models will also have this plate or sticker on the transom bracket. The first two characters identify the engine size in liters 23 represents the 30 represents the and so forth. The third character identifies the fuel delivery system; 2 designates a 2 bbl carburetor, 4 is a 4 bbl carburetor, and F is a fuel injected engine. The fourth character designates a major engine or horsepower doesn't let you know what the change was, just that there was some sort of change. A means it is the first model released, would be the second, and so forth The fifth character designates what type of steering system was used; M would be manual steering and P would be power steering. Now here's where it gets interesting; on 1987 engines, the sixth, seventh and eighth characters designate the model year. The sixth and seventh actually show the model year, while the eighth is a random model year version code. ARJ, ARF, FTC, SRC or SRY show 1987. On 1988-90 engines, the sixth character designates the direction of propeller rotation. is right hand, L is left hand and E is either. Also on 1988-90 engines, the seventh, eighth and ninth characters designate the model year. The seventh and eighth actually show the model year, while the ninth is a random model year version code. GDE or GDP is 1988, MED or MEF is 1989, PWC, PWR or PWS is 1990. Any remaining characters are proprietary. So in example, a Model number on the ID plate that reads would designate a 1987 engine with a 2 bbl carburetor and manual steering, first model released. Engine Model Designations All engines covered here utilize unique identifiers assigned by OMC; surnames if you will-2.3, etc. Obviously the first two characters designate the engine size in (L). The second letter, a G or and F designate the engine manufacturer; General Motors (G) or Ford (F). The third through fifth letters can be found in different combinations, but the individual letter designates the same thing regardless of position. L designates limited output. S and X designate superior output-a will always have a lesser horsepower rating than a in a given model year; a will be less than a i designates that the engine is fuel injected, if there is no then you know the engine uses a carburetor. REMOVAL INSTALLATION CULT See Figures 2,3 and 1. Check the clearance between the front of the engine and the inside edge of the engine compartment bulkhead. If clearance is less than 6 in. you will need to remove the stern drive unit because there won't be enough room to disengage the driveshaft from the engine coupler. More than 6 in. will provide enough working room to get the engine out without removing the drive, BUT, we recommend removing the drive anyway. If you intend on doing anything to the mounts or stringers, you will need to re-align the engine as detailed in the Engine Alignment section-which requires removing the drive, so remove the drive! 2. Remove the stern drive unit as detailed in the Drive Systems section. 3. Open or remove the engine hatch cover. ENGINE MECHANICAL -FORD 4 CYLINDER ENGINES 3-3 Fig. Decoding the engine model number is easy Fig. 2 Disconnect the power steering lines at the cylinder Fig. 3 Disconnect the instrument cable connector \ ine hoist 4. Disconnect the battery cables (negative first) at the battery and then disconnect them from the engine block and starter. Make sure that all switches and systems are OFF before disconnecting the battery cables. 5. Disconnect the two power steering hydraulic lines at the steering cylinder (models wlpower steering). Carefully plug them and then tie them off somewhere on the engine, making sure that they are higher then the pump to minimize any leakage. 6. Disconnect the fuel inlet line at the fuel pump or filter (whichever comes first on your particular engine) and quickly plug it and the inlet-a clean golf tee and some tape works well in this situation. Make sure you have rags handy, as there will be some spillage. 7. Tag and disconnect the two-wire connector. 8. Pop the two-wire trimltilt sender connector out of the retainer and then disconnect it. You may have to cut the plastic tie securing the cable in order to move it out of the way. 9. Locate the large rubber coated instrument cable connector (should be on the starboard side), loosen the hose clamp and then disconnect it from the bracket. Move it away from the engine and secure it. On most models, you will also need to unplug the three-wire trimltilt cable connector just above Take note of your throttle arm attachment stud-is it a close" or a "pull-to-close"? 10. Disconnect the remote control shift cable and the transom bracket shift cable from the engine shift bracket. Remove the cables from the anchor pockets and the shift lever. Tape the trunnions to the cables so that the adjustment does not get knocked out of kilter. 11. Remove the cotter pin and washer from the throttle arm. Loosen the anchor block retaining nut and then spin the retainer away from the cable trunnion. Remove the throttle cable from the arm and anchor bracket. Be sure to mark the position of the holes that the anchor block was attached to. 12. Loosen the hose clamps (4) and disconnect the exhaust elbow bellows from elbow. You may want to spray some WD-40 around the lip of the hose where it connects to the elbow, grasp it with both hands and wiggle it back and forth while oullina down on it. 13. Drain the as detailed in the section. 3-4 ENGINE MECHANICAL -FORD 4 CYLINDER ENGINES 14. Loosen the hose clamp on the water supply hose at the transom bracket and carefully slide it off the water tube. Attach the hose to the engine. Disconnect the shift cables and position them out of the way. 16. Tag and disconnect remaining lines, wires or hoses at the engine. 17. Attach a suitable engine hoist to the lifting eyes (usually front starboard side, rear port side) and take up any line slack until it is just taught. The engine hoist should have a capacity of at least 1500 (680 kg). 18. Locate the rear engine mounts and remove both lock nuts and flat washers. 19. Locate the front engine mounts and remove the two lag bolts. 20. If you listened to us at the beginning of the procedure, the drive unit should be removed. If so, slowly and carefully, lift out the engine. Try not to hit the power steering control valve, or any other accessories, while removing it from the engine compartment. If you didn't listen to us, and you had sufficient clearance in the engine compartment, the drive unit is probably still installed. Raise the hoist slightly until the weight is removed from the mounts and then carefully pull the engine forward until the driveshaft disengages from the coupler, now raise the engine out of the compartment. To install: 21. Apply Engine Coupler grease to the splines of the coupler. 22. Slowly lower the engine into the compartment. If the drive unit was not removed, AND the crankshaft has not been rotated, insert the driveshaft into the coupler as you push the engine backwards until they engage completely and then lower the engine into position over the rear mounts until the front mounts just touch the stringers. If the shaft and coupler will not align completely, turn the crankshaft or driveshaft slightly until they mate correctly. If the drive was removed, or the mounts were disturbed in any way, lower the engine into position over the rear mounts until the front mount just touches the stringer. 23. lnstall the two flat washers into the recess in the engine bracket side of the rear mounts and then install the two lock nuts. Tighten them to 28-30 ft. Ibs. (38-40 Nm). Never use an impact wrench or power driver to tighten the locknuts. 24. lnstall the lag bolts into their holes on the front mounts and tighten each bolt securely. 25. If the drive was removed, the mounts were disturbed or the didn't mate correctly, perform the engine alignment procedure detailed in this section. We think it's a good idea to do this regardless! After you've performed the alignment procedure, make sure that you hold the top adjusting nut and tighten the lower nut on the mount to 120 ft. Ibs. (136-163 Nm). 26. Reconnect the exhaust bellows by sliding it up and over the elbow, position the clamps between the ribs in the hose and then tighten the clamps securely. Make sure you don't position the clamps into the expanding area. 27. Reconnect the water inlet hose. Lubricate the inside of the hose and wiggle it onto the inlet tube. Slide the clamp over the ridge and tighten it securely. This sounds like an easy step, but it is very important-if the hose, particularly the underside, is not installed correctly the hose itself may collapse or come off. Either scenario will cause severe damage to your engine, so make sure you do this correctly! 28. Carefully, and quickly, remove the tape and plugs so you can connect the power steering lines. Tighten the large fitting to 15-17 ft. Ibs. (20-23 Nm) and the small fitting to 10-12 ft. Ibs. Nm). Don't forget to check the fluid level and bleed the system when you are finished with the installation. 29. Reconnect the connector so the two halves lock together. 30. Reconnect the trim position sender leads, the instrument the enaine around wire, the batterv cables and all other wires, lines of hoses that during Make sure you swab a light coat of grease around the fitting for the large enginelinstrument cable plug. Always make certain that all switches and systems are turned OFF before reconnecting the battery cables. Make sure all cables, wires and hoses are routed correctly before initially starting the engine. 31. Unplug the fuel line and fitting and reconnect them. Remember to check for leaks as soon as you start the engine. lnstall and adjust the throttle cable. For complete details, please refer to the Fuel System section): a. Remember we asked you to determine if you had a "push-to-close" or "pull-to-open"throttle cable (the throttle arm stud)? Position the remote control handle in Neutral-the propeller should rotate freely. b. Turn the propeller shaft and the shifter into the forward gear detent position and then move the shifter back toward the Neutral position halfway. c. Position the trunnion over the groove in the throttle cable so the internal bosses align and then snap it into the groove until it is fully seated. lnstall the into the anchor block so the open side of the trunnion is against the block. Position the assembly onto the bracket over the original holes (they should be the lower two of the four holes) and then install the retaining bolt and nut. When the nut is securely against the back of the bracket, tighten the bolt securely. e. lnstall the connector onto the throttle cable and then pull the connector until all end play is removed from the cable. Turn it sideways until the hole is in alignment with the correct stud on the throttle arm. Slide it over the stud and install the washer and a new cotter pin. Make sure the cable is on the same stud that it was removed from. Tighten the jam nut against the connector 33. lnstall and adjust the shift cables. Please refer to the Drive Systems section for further details. 34. Check and refill all fluids. Start the engine and check for any fuel or coolant leaks. Go have fun! ENGINE ALIGNMENT 5 Engine alignment is imperative for correct engine installation and also for continued engine and drive operation. It is a good idea to ensure proper alignment every time that the drive or engine have been removed. Engine alignment is checked by using OMC alignment tool and handle (Volvo and Engine alignment is adjusted by raising or lowering the front engine 1. With the drive unit off the vessel, slide the alignment tool through the gimbal bearing and into the engine coupler. It should slide easily, with no binding or force. not, check the gimbal bearing alignment as detailed in the Drive Systems section. If bearing alignment is correct, move to the next step. 2. If your engine utilizes a jam nut on the bottom of the mount bolt, loosen it and back it off at least 112 in. 3. Loosen the lock nut and back it off. 4. Now, determine if the engine requires raising or lowering to facilitate alignment-remember, the alignment tool should still be in position. Tighten or loosen the adjusting nut until the new engine height allows the alignment tool to slide freely. Fig. 5 Install the alignment tool through the gimbal bearing ENGINE MECHANICAL -FORD 4 CYLINDER ENGINES 3-5 5. Hold the adjusting nut with a wrench and then tighten the lock nut to 100-120 ft. Ibs. (136-163 Nm). If your engine uses a jam nut, cinch it up against the lock nut. 6. Remove the alignment tool and handle. REMOVAL INSTALLATION See Figures 6 and 7 T 6. Turn the assembly upside down and clamp the nut in a vise. Spin the assembly until the holes in the mounting plate are directly opposite any two of the flat sides on the nut. This is important, otherwise the slot on the engine pad will not engage the mount correctly. Secure the mount in this position and tighten the bolt to 18-20 Ibs. (24-27 Nm) on 1987-88 engines, or 44-52 ft. Ibs. (60-71 Nm) on 1989-90 engines. 7. Remove the mount from the vise and position it on the transom Install the bolts and washers and tighten each to 20-25 ft. Ibs. (27-34 8. lnstall the engine, making sure that the slot in the engine pad engages the square nut correctly. lnstall the two washers and locknut and tighten it to 28-30 ft. Ibs. Nm). 1. Position an engine hoist over the engine and hook it the two engine lifting. 2. Remove the two lag screwsibolts on each side of the mount where it rests on the stringer. 3. Raise the engine just enough to allow working room for removing the mount. 4. Remove the 3 mount-to-engine mounting bolts with their lock washers and lift out the mount. 5. Measure the distance between the top of the large washer on the mount and the flat on the lower side of the mounting bracket. Record it. 6. Position a wrench over the bottom nut on the adjusting bolt, just underneath the mount to, hold the shaft and then remove the top nut. Lift off the bracket. 7. Remove the two lock nuts from the bolt and slide out the adjusting bolt. Remember which washer goes where. The rubber mount and lower foot are serviced as an assembly To install: 8. Slide the adjusting bolt up through the mount and then position the small and large washers over the bolt-large over small. 9. Spin on the first (lower) lock nut and tighten it to 60-75 ft. Ibs. 102 Nm). 10. Screw on the upper lock nut and then position the mount bracket over the bolt. Install the washer and adjusting nut and check the measurement taken in Step 5. Move the upper lock nut up or down until the correct specification is achieved and then tighten the adjusting nut to 120 ft. (136-163 Nm). 11. Spray the 3 mounting bolts with Loctite Primer N and allow them to air dry. Once dry, coat the bolts with Loctite or OMC Thread Sealing Agent and attach the mount to the engine. Tighten the bolts to 32-40 ft. Ibs. Nm). 12. Position the mount over the lag screw holes and then slowly lower the engine until all weight is off the hoist. Install and tighten the lag screws securely. 13. If you're confident that your measurements and subsequent adjustment place the engine exactly where it was prior to removal, then you are through. If you're like us though, you may want to check the engine alignment before you fire up the engine. REMOVAL INSTALLATION + See Figure 8 T Remove the engine as previously 2. Loosen the two bolts and remove the mount from the transom alate. 3. Hold the square nut with a wrench and remove the shaft bolt. Be sure to take note of the style and positioning of the two mount washers as you are removing the bolt. Mark them, lay them out, or write it down, but don4 forget their orientation!! To install: 4. Slide the lower of the two washers onto the mount bolt, exactly as it came off (this should be the thin one). 5. Slide the bolt into the flat side of the rubber mount, install the remaining washer (as it came off!) and then spin on the square nut. Do not tighten it yet. Incorrect washer installation will cause excessive vibration during engine operation. Fig. 7 ...and a closer view Fig. 6 A good view of the front mount ... 3-6 ENGINE ECHANICAL -FORD 4 CYLINDER ENGINES Fig. 8 A good view of the rear mount I I Fig. 9 If the special tool is not available, you can usually compress the surina with a small REMOVAL INSTALLATION 1. Open or remove the engine compartment hatch. the negative battery cable. 2. Loosen the clamp and remove the crankcase ventilation hose at the cover (if equipped). Carefully move it out of the way. 3. If your engine has a spark plug wire retainer attached to the cover, the wires or remove the retainer. 4. Loosen the cover mounting bolts (8) and lift off the cylinder head cover. Take note of any harness or hose retainers and clips that might be attached to certain of the mounting bolts; you need to make sure they go back in the same place. To install: 5. Clean the cylinder head and cover mounting surfaces of any residual gasket material with a scraper or putty knife. 6. Coat the cylinder head mounting surface with high temperature, oil resistant sealer. 7. Position a new gasket on the cylinder head and then position the cover. Tighten the mounting bolts to 48-84 inch Ibs. Nm). Make sure any retainers or clips that were removed are back in their original positions. 8. Reconnect the spark plug wires. 9. Connect the crankcase ventilation hose. Check that there were no other wires or hoses you may have repositioned in order to gain access to the cover. 10. Connect the battery cables. REMOVAL INSTALLATION See Figures 9 and 10 Open or remove the engine hatch cover and disconnect the negative battery cable. Remove the cylinder head cover as detailed previously. 2. Rotate the camshaft until the tip of the camshaft lobe over the rocker is facing upward-the heel is resting on the rocker arm. 3. Install the valve tool over the valve spring and depress the spring until the rocker arm is released and you can lift it out. 4. Remove the hydraulic valve adjuster. 5. Repeat this procedure for each remaining rocker arm and adjuster. To install: 6. Clean and inspect the rocker assemblies for nicks, scratches or signs of undue wear. If the pad at the valve end of the arm shows a groove, replace the arm. 7. Coat all bearing surfaces of the rocker assembly and adjuster with engine oil. Fig. 10 A good look at the valve train ENGINE MECHANICAL -FORD 4 CYLINDER EN 8. Rotate the camshaft until the lobe is pointing up on the cylinder that you are working on. 9. Depress the valve spring with the special tool again and insert the rocker arm into position. 10. Repeat this procedure for each remaining rocker arm and adjuster, making sure that the spring has been released and the tool removed before moving on to the next arm. 11. Adjust the valves and install the cylinder head cover. 12. Connect the battery cable and check the idle speed. VALVE ADJUSTMENT These engines utilize hydraulic valve lifters, although no need for periodic valve adjustment, it is necessary to perform a preliminary adjustment after any work on the valve assembly. All adjustment should be undertaken while the lifter is on the base circle of the camshaft lobe for that particular cylinder. This means the opposite side of the pointy part of each lobe. 1. Rotate the camshaft by hand until the base circle (heel) of the camshaft lobe is resting on the cam follower at the valve you intend to adjust; the lobe will be pointing straight up. 2. Install the valve tool into position and slowly apply pressure to the handle until the until the cam follower has collapsed the hydraulic lash adjuster completely. 3. While using the tool to hold the adjuster in the collapsed position, insert a feeler gauge between the base of the camshaft lobe and the follower. Clearance should be in. although 0.055 in. is acceptable. 4. If clearance is out of range, remove the cam follower again and inspect it for any signs of damage. If the follower appears to be OK and not showing signs of excessive wear, measure the valve spring height between the pad and the retainer-if not within 1 19132 in., replace the spring. 5. If the valve spring installed height was within specifications, check that the camshaft is within specifications. If the camshaft checks out OK, install a new adjuster and recheck the lash a final time. REMOVAL INSTALLATION 1. Open or remove the engine compartment hatch. the negative battery cable. 2. Drain all water from the engine, manifold and exhaust elbow as detailed in the Maintenance section. 3. Loosen the 4 clamps holding the exhaust hose bellows to the high- rise elbow and wiggle the bellows off of the elbow. 4. Disconnect the 2 shift cables at the shift bracket on the manifold. Remove the 2 locknuts and the bolt attaching the bracket to the manifold and lift off the bracket, positioning it on the engine out of the way. 5. Remove the 4 mounting bolts and their lock washers and then lift off the high-rise elbow-you may have to persuade it with a few taps from a rubber mallet. 6. On models with power steering, loosen the drive belt and then remove the pump and bracket from the thermostat housing on the leading edge of the manifold. 7. Disconnect the small water line coming off the starboard side of the thermostat housing. Have a rag handy, because there will probably be some water spillage even though you've already drained the system. 8. Remove the 2 mounting bolts and lock washers securing the thermostat housing to the manifold. Tap the housing a few times lightly with a rubber mallet until it separates from the manifold and then lift it off and position it out of the way with the remaining hoses still attached. Remove the gasket and thermostat. 9. On models equipped with power steering, remove the oil cooler mounting bolts and pull it away from the bottom of the manifold. You should not have to disconnect the hydraulic lines or remove the cooler completely. 10. Remove the 3 remaining locknuts and the upper bolt and then lift off the manifold. Remove the gasket. Once again, you may have to give the manifold a few friendly taps with a rubber mallet. To install: 11. Clean all gasket and mating surfaces thoroughly (elbow, manifold and thermostat housing) and inspect the components for cracks, undue wear or other signs of damage. 12. Position a new manifold gasket over the studs so the connecting bar is on the bottom and push it up against the block. No sealer or adhesive is necessary. 13. Position the manifold over the studs and into position. Thread on the lock nuts (use new washers) and tighten them to ft. Ibs. Nm). Install the upper bolt and tighten it to ft. (27-34 Nm). Install the elbow with a new gasket and tighten the 4 bolts securely. 15. Reposition the oil cooler if you removed it and tighten the mounting bolt securely. 16. Slide a new cork gasket over the element end of the thermostat and install them into the housing. Coat both sides of a new housing-to-manifold gasket with OMC Sealing Compound, position it on the manifold and then move the housing into place. Slide in the mounting bolts (the longer one goes on the inside) and tighten them to 20-25 ft. Ibs. Nm). Reconnect the small water line and tighten the clamp securely, being careful not to pinch the hose. 17. Position the shift bracket and the 2 nuts (use new washers if possible) and tighten to 30-35 ft. Ibs. Nm). in the bolt to the elbow and tighten it to 12-14 ft. Connect the shift cables. 18. Install the power steering pump, if removed, and adjust the belt tension. 19. Coat the elbow outlet with a bit of soapy water and then wiggle the bellows up and into position. Tighten the hose clamps securely. 20. Reconnect the battery cables and run the engine. Check for any water leaks. REMOVAL INSTALLATION Drain the cooling system. 2. Loosen the hose clamps and slide off the exhaust Lubricating the elbow-to-bellows connection with a bit of soapy water will help break the hose loose. 3. Loosen the 2 shift bracket lock nuts and unscrew them as far as you can without removing the nut from the stud. 4. Remove the 4 elbow mounting bolts on the elbow mating flange and swing the shift cable anchor bracket out of the way. 5. Lift it off the elbow. A little friendly persuasion with a soft rubber mallet may be necessary! Be careful though, no need lo take out all your aggressions on the poor thing. 6. Remove the and restrictor plate (if equipped). You can throw away the but keep the plate if your engine uses it. To install: 7. Clean the mating surfaces of the manifold and elbow thoroughly, coat both sides of a new gasket with Gasket Sealing compound and position it onto the manifold flange. 8. If your engine was so equipped, position the restrictor plate second gasket onto the manifold, Don't forget to coat the gasket with sealing compound. 9. Position the elbow on the manifold, position the anchor bracket and screw the bolts in finger tight. Tighten all four to 12-14 Ibs. Nm). 10. Tighten the 2 lower nuts on the shift bracket to ft. Ibs. Nm). 11. Slide the exhaust hose, while wiggling it, all the way onto the elbow and tighten the clamp screws securely. Make sure that the 2 upper clamps are riding in the channels on the upper side of the bellows. 3-8 ENGINE MECHANICAL -FORD 4 CYLINDER ENGINES REMOVAL INSTALLATION See Figures 11 and 12 TE Loosen all four hose clamps, two on top of the hose and two on the bottom. 2. Drizzle a soapy water solution over the top of hose where it mates with the exhaust elbow and let it sit for a minute. 3. Grasp the hose with both hands and wiggle it side-to-side while pulling down on it until it separates from the elbow. 4. Now wiggle it while pulling upwards until it pops off the exhaust pipe. Make sure that you secure the exhaust pipe while pulling off the hose. 5. Check the hose for wear, cracks and deterioration. 6. Coat the inside of the lower end of the hose with soapy water and wiggle it into position on the pipe. Remember to install the two clamps before sliding it over the end of the pipe. There are usually two ribs on one end of the hose-this is the side that attaches to the exhaust elbow. Do not position this end onto the exhaust pipe. 7. Slide two clamps over the upper end (the side with two ribs!), lubricate the inside with soapy water and wiggle the hose over the elbow until it is in position. 8. Tighten all four clamps securely. I I Fig. 11 Loosen the lower clamp screws and then pull the bellows off of the exhaust pipe Fig. 12 Be sure that the bellows end with two ribs is on top REMOVAL INSTALLATION 1. It is unlikely you will be able to get the pipe off without removing the engine, so remove the engine as previously detailed. 2. Loosen the four retaining bolts at the transom shield and then remove the exhaust pipe. Carefully scrape any remnants of the seal from the pipe and transom mounting surfaces. The pipe mounting holes in the transom shield utilize locking inserts. NEVER clean the holes or threads with a tapping tool or you risk damaging the locking feature of the threads. 3. Coat a new seal with OMC Adhesive M or 3M Scotch Grip Rubber Adhesive and position it into the groove on the transom shield mating surface. 4. Coat the mounting bolts with Gasket Sealing Adhesive. Position the exhaust pipe, insert the bolts and tighten them to 10-12 A. Ibs. (14-16 Nm) on 1987-89 engines; or 20-25 ft. Ibs. (27-34 Nm) on 1990 engines. Make sure that the lines are routed correctly (above and behind) before tightening the pipe to the transom. 5. Install the engine. EXHAUST VALVE (FLAPPER) REPLACEMENT Remove the exhaust hose from the elbow and The flapper is located in the upper end of the pipe. 2. The valve is held in place by means of a pin running through two bushings in the sides of the pipe. Position a small punch over one end of the pin and carefully press the pin out of the pipe. Make sure you secure the valve while removing the retaining pin so it doesn't fall down into the exhaust pipe. 3. Press out the two bushings and discard them. Coat two new with Scotch Rubber Adhesive and press them back into the sides the pipe. 4. Position the new valve into the pipe with the long side DOWN. When at the valve, the molded retainina rinas are off-center-the side with the should face the top of the the valve is in place, coat the pin lightly with engine oil and slowly slide it through one of the bushings, through the two retaining holes on the valve and then through the opposite bushing. Make sure the pin ends are flush with the sides of the pipe on both sides. 5. Install the exhaust hose. REMOVAL INSTALLATION See Figure 13 Open the engine and disconnect the cables. Drain all water from the engine as detailed in the Maintenance section. 2. Disconnect the throttle cable at the bellcrank and anchor block. Disconnect the swivel linkage at the throttle arm on the carburetor. 3. Carefully disconnect the fuel lines at the carburetor and fuel filter. Plug the lines and be careful to wipe up any spilled fuel. 4. Remove the fuel line clamp bracket at the intake manifold and then disconnect the fuel lines at the fuel pump. Remove the lines. Pull the fuel pump vent tube from the nipple on the carburetor and position it out of the way. 5. Loosen the hose clamp and then wiggle the water line off of the nipple on the end of the manifold. Tie the line back and out of the way with the open end facing upward. ENGINE MECHANICAL -FORD 4 CYLINDER ENGINES 6. Remove the fuel filter mounting bolts and then pull the filter off of the manifold and sit it down somewhere so that it is supported in the upright position. It is not necessary to remove the clamp from the oil dipstick. 7. Remove the plastic cover and then the flame arrestor. 8. Tag and disconnect the electrical lead to the choke at the housing. 9. Remove the 4 mounting nuts and lift off the carburetor and gasket, 10. Disconnect the distributor lead at the ignition coil and then remove the distributor cap, with the leads still attached, and position it out of the way. Pull out the rotor and then cover the top of the distributor with a clean rag. 11. Pop the PCV valve out, with the hose still connected, and position it out of the way. 12. Remove the 2 upper rear manifold bolts and move the throttle cable bracket out of the way. 13. Remove the 2 upper front manifold bolts and move the lifting bracket out of the way. 14. Remove the 4 lower manifold bolts, keeping them separate from the longer upper bolts. Don't forget the clamps on the 2 end bolts when you are removing them, 15. Tap the manifold lightly a few time with a rubber mallet until it breaks loose from the engine and then remove the manifold and gasket. To install: 16. Clean all mating surfaces thoroughly so that there is no residual gasket material. Inspect the components carefully for cracks, burrs and other signs of wear or damage. 17. Insert a bolt (one of the longer ones) through the upper hole on each end of the manifold and then position the gasket over the bolts and onto the manifold. the manifold onto the block and tighten the 2 bolts finger- tight. 18. Thread in the 4 lower bolts (the short ones) until they are finger- tight-don't forget the clamps on the 2 outside bolts. 19. Position the lifting and throttle cable brackets and then install the 2 remaining upper bolts through the brackets and manifold. 20. Tighten the manifold bolts, in the sequence illustrated, to 60-84 inch Ibs. (6.8-9.5 Nm). Follow the same sequence and then tighten them once more to 14-18 ft. Ibs. (19-24 Nm). 21. Push the PCV valve back in place. lnstall the rotor and distributor cap. Connect the lead to the ignition coil. 22. Position a new carburetor gasket onto the manifold so that the 2 rounded nubs are facing the engine and then install the carburetor. Tighten the nuts to 12-14 ft. Ibs. Nm). 23. Connect the electrical lead at the choke housing and the snap the swivel linkage onto the ball stud at the throttle arm. 24. lnstall the flame arrestor and plastic cover. lnstall the vent hose bracket. 25. Position the fuel filter and thread in the bolts so the dipstick tube clamp is under the inner bolt. Tighten both bolts securely. 26. Push the water line over the manifold nipple and tighten the clamp securely without pinching the hose. 27. Remove the plugs and connect the fuel lines to the carburetor and filter. Attach the fuel line bracket and reconnect the vent hose at the carburetor. 28. Connect both fuel lines to the fuel pump and tighten the nuts securely. Fig. 13 Intake manifold tightening sequence 29. Connect the throttle cable at the bellcrank; position the flat washer and then insert a new cotter pin. Pivot the retainer down until you can get the trunnion into the anchor block and then tighten the nut securely. 30. Connect the battery cables, start the engine and check for any fuel or water leaks. REMOVAL & INSTALLATION See Figures 14 and 15 More times than not this procedure will require the of the engine. Your boat and its unique engine installation will determine this, but the procedure is almost always easier with the engine removed from the boat. Remove the engine as previously detailed in this section. 2. If you haven't already drained the engine oil, do it now. Make sure you have a container and lots of rags available. 3. Remove the starter motor as detailed in the Electrical section. Although not absolutely necessary, this step will make the job much easier. 4. Remove the oil withdrawal tube from the oil drain plug fitting. 5. Loosen and remove the oil pan retaining bolts and (22 on engines and 20 on 1990 engines), starting with the center bolts and working out toward the pan ends. Lightly tap the pan with a rubber mallet to break the seal and then lift it off the cylinder block. If your engine stand will allow for rotating the engine, you'll find that this will be easier with the pan facing 6. Lift the reinforcement strips off of the pan flange on 1990 engines. To install: Clean the pan mating surfaces of any residual gasket material with a scraper or putty knife. Make sure that no old gasket material has been pressed into the retaining bolt holes in the pan, block or front cover. Clean the pan itself thoroughly with solvent. 1987-89 Engines: 7. Apply a 0.125 in. bead of RTV sealant to the joint where the front cover and block meet. lnstall new front and rear seals into the front cover and over rear bearing move quickly here as the sealant sets up very quickly. Make sure that you press the tabs on each seal completely into the cylinder block. 8. Apply gasket adhesive to the oil pan flange and also to 2 new side gaskets. Allow the adhesive to set up until it is tacky and then install the gaskets onto the flange on each side of the pan. 9. a guide pin into a hole on each side of the cylinder block mounting surface and then the oil pan onto the block. lnstall 4 bolts (two front and two rear) and tighten them to 96-120 inch Ibs. (10.8-13.6 10. lnstall the remaining 18 M6 bolts and tighten them to 72-96 inch Ibs. (8.1-10.8 Nm), working clockwise around the pan from. 11. Coat a new gasket with RTV sealant and then position the gasket onto the pan being very careful to line up all the holes. 1990 Engines: 12. Apply a 0.125 in. bead of RTV sealant to the two joints (A) where the front cover meets the pan and the four joints where the oil pan meets the block 13. Apply gasket adhesive to a new oil pan gasket and allow it to set up until tacky. Position the gasket onto the oil pan flange making sure that all the holes line up correctly. Insert a guide pin into a hole on each side of the cylinder block mounting surface and then position the oil pan onto the block. Position the reinforcing strips on each side of the pan and then install 18 M6 bolts finger- tight. 15. Remove the 2 guide pins and thread in the remaining two M6 bolts. Tighten all bolts to 72-96 inch Ibs. (8.1-10.8 in a clockwise pattern working around the pan. 16. lnstall the oil drain fitting and finger tighten the bolt. Rotate the fitting and then attach the withdrawal tube. Tighten the fitting bolt and flare nut to 8 ft. (20-24 17. lnstall the starter motor and then install the engine (if removed). Run the engine up to normal operating temperature, shut it off and check the pan for any leaks. 3-10 ENGINE MECHANICAL -FORD 4 CYLINDER ENGINES Oil Pan Fig. 14 The oil pan uses a two-piece soft rubber gasket and two seals-1987-89 engines A Fig. 15 The oil pan uses a one-piece soft rubber gasket-1990 enaines The two-piece oil utilizes an inner and outer rotor and a pressure relief valve. A baffled pick-up tube is bolted to the body of the pump. The pump is driven via the auxiliary shaft which is itself driven by the crankshaft via a timing belt. REMOVAL INSTALLATION See Figures 16 and 17 Remove the oil pan as previously detailed. you probably need to remove the engine for this procedure. 2. Loosen and remove the pump pick-up tube brace bolt. 3. Loosen and remove the two pump mounting bolts and lift off the pump assembly. Pull out the pump shaft and take note of its orientation in the bore. Insert the pump shaft in the same manner in which it came out. 5. Check that the pump and block mating surfaces are clean and then position the pump over the block so that the pump shaft slot is aligned correctly. Do not use a gasket or RTV sealant. 6. Tighten the pump mounting bolts to 14-21 ft. (19-28 Nm). 7. Position the pick-up tube brace and tighten the bolt to 60 inch Ibs. (7 Nm). Install the oil pan and engine. DISASSEMBLY ASSEMBLY See Figure 17 1. Remove the oil pan and oil pump. 2. Remove the mounting bolts (2) and pull off the pick-up tube. 3. Remove the 4 cover screws and lift off the cover. 4. Lift out the two rotors and sit them down carefully as they break very easily. The pump body, relief valve and spring are serviced as an assembly. To assemble: 5. Clean all components thoroughly in solvent and allow them to air dry completely-compressed air will speed the process if available. Clean the inside of the housing with a small toothbrush if necessary. 6. Check the cover, inner housing and both rotors for scratching, nicks or any other signs of wear. Replace as necessary. 7. Install the rotors so that the ID marks on each component are facing each other. 8. Measure the clearance between the outer rotor race and the inner bore of the housing. Clearance should be 0.001-0.0013 in. 9. With the rotors still installed in the housing, lay a straight edge across the top of the assembly. Use a flat feeler gauge and measure the clearance between the straight edge and the rotors. must be in. 10. Check the bearing clearance by measuring the outer diameter of the pump shaft with a micrometer and then subtracting that figure from the inner diameter of the housina Clearance should be 0.0015-0.0029 in. 11. Measurements outside of soecifications on anv of the will dictate of the associated '12. Install the cover and tighten the screws to 72-120 inch Ibs. (8.1-13.6 Nm). 13. Connect the pick-up tube to the housing and tighten the 2 bolts to 14- 21 ft. Ibs. (19-28 14. Install the oil pump and pan. REMOVAL INSTALLATION See Figures and 20 Remove the engine from the boat as detailed in this section. 2. Although not strictly necessary, we recommend removing the starter. 3. Cut the plastic tie that secures the housing drain hose (if equipped) and the pull the hose out of the fitting. ENGINE MECHANICAL -FORD 4 CYLINDER ENGINES 3-11 Oil Fig. 16 Removing the oil pump assembly 4. Remove the 4 or 5 mounting bolts and slide out the lower flywheel cover. and remove any connections attached to either of the ground studs on each side of the flywheel. Move the electrical leads out of the way. 6. Loosen the remaining retaining bolts (some of which were already removed with the shift bracket) for the flywheel housing and remove it. Take note of the positioning of any clamps so they may be installed in the same position. 7. Slide a wrench behind the coupler and loosen the six flywheel mounting nuts gradually and as you would the lug nuts on your car or that is, in a diagonal star pattern. 8. Remove the coupler and then the flywheel. To install: 9. Thoroughly clean the flywheel mating surface and check it for any nicks, cracks or gouges. Check for any broken teeth. 10. Install the flywheel over the dowel on the crankshaft. The engine uses a completely different coupler than other OMC engines-make sure that you have the correct part if replacing with a new one. Cover Pump Housin Fig. 17 Exploded view of the oil pump 11. Slide the over so that it sits in the recess on the flywheel. Install new washers and tighten the mounting bolts to 14-17 ft. Ibs. Nm). Once again use the star pattern while tightening the bolts. 12. Position the flywheel housing and the shift bracket. Make sure that the clamps are in their original positions and insert the mounting bolts. Tighten them to 28-36 ft. Ibs. (38-49 Nm). ID Mark Rotors Fig. 18 Remove the upper cover. Fig. 20. Tighten the mounting bolts in a pattern Fig. 19...and en pull off the coupler after removing the bolts 3-12 ENGINE MECHANICAL -FORD 4 CYLINDER ENGINES 13. Install the washer, lock washer and inner nut on the ground stud and tighten it to 20-25 ft. Ibs. (27-34 Nm). Attach the electrical leads, install another lock washer and then tighten the outer nut securely. 14. Slide the lower flywheel cover into place and tighten the bolts to 60- 84 inch Ibs. Nm). 15. Attach the drain hose with a new plastic tie. 16. Install the starter and engine. REMOVAL INSTALLATION Two Piece Oil Seal See Figures and 24 These engines utilize a two-piece rear main seal. The seal can be removed without removing the crankshaft. You will need to remove the engine for this procedure though. Remove the engine as detailed previously in this section. 2. Remove the oil pan and pump as detailed previously in this section. 3. Loosen the retaining bolts and remove the rear main bearing cap. Carefully insert a small or awl and remove the lower half of the seal from the cap. Do not damage the seal seating surface. 4. Loosen the remaining bearing bolts just enough so that the crankshaft drops down 1116 in. at the rear. 5. Using a hammer and a small drift or punch, tap on the end of the upper seal until it starts to protrude form the other side of the race. Grab the protruding end with pliers and pull out the remaining seal half. Upper and lower seals must replaced as a pair. Never replace only one seal. 6. Clean the seal grooves thoroughly with a sma bottle brush. Fig. 22 Drive out the old upper seal with a small drift Fig. 21 Exploded view of the rear seal 7. Check that you have the correct new seal. Seals with a hatched inner surface can only be used on left hand rotation engines, smooth seals can be used on any engine. Coat the lip and bead thoroughly with motor oil, but keep oil away from the seal parting surfaces. Your seal kit should come with an installation tool, if not, take a 0,004 in. feeler gauge and cut each side back about a half inch so that you're left with an 11164 inch point. Bend the tool into the gap between the crankshaft and the seal seating surface. This will be your "shoe horn". 9. Position the upper half of the seal (lip facing the engine) between the crank and the tool so that the seal's bead is in contact with the tool tip. Roll the seal around the crankshaft using the tool as a guide until each end is flush with the cylinder block. Remove the tool. Make sure that the tab on the seal is facing the rear. 10. Tighten up all bearing cap bolts (except the rear) to bring the crankshaft back up into position. 11. Insert the lower seal half into the main bearing cap with the lip facing the cap and the tab facing the rear. Start it so that one end is slightly below the edge of the cap and then use the tool to shimmy the seal all the way in until both edges are flush with the edge of the cap. Remove the tool. 12. Make sure that the caplblock mating surfaces and the seal ends are free of any oil and then apply a small amount of Perfect Seal to the block just behind where the upper seal ends are. away Fig. 23 Fabricate a seal installation tool out of an old feeler gauge ... 1 tool Seal 3-Engine block 4-Crankshaft Fig. 24 ...and then use the tool to feed the seal around the crankshaft ENGINE MECHANICAL -FORD CYLINDER Do not aet sealant on the seal ends. 13. lnstall the bearing cap and tighten the bolts on all caps to 80-90 ft. Ibs. (109-122 Nm). 14. lnstall the oil pump and pan. lnstall the engine. One Piece Oil Seal See Figure 25 1. Remove the flywheel housing and cover as detailed in this section. 2. Remove the engine coupler and flywheel from the engine as detailed in this section. 3. Remove the engine and then the oil pan. 4. Using an awl, punch a hole into the metal surface the seal between the inner lip and the cylinder block. 5. lnstall the threaded end of a slide hammer tool (# into the end of the crankshaft and remove the seal. 6. Thoroughly clean the seal and mating surface with clean engine oil. 7. Position the seal on the installer tool (# so that the spring side is facing the engine. Position the tool into place on the crankshaft, install the bolts and gradually (and alternately) tighten the bolts until the seal seats itself. The rear (outer) edge of the seal must be within 0.005 in. of the rear edge of the cylinder block. If the bolts supplied with the installation tool are not available, bolts may be used. 8. Remove the tool and install the oil pan. 9. lnstall the engine, flywheel and coupler. FRONT OF ENGINE Fig. 25 A good shot of the one piece seal and removal tool REMOVAL INSTALLATION See Figure 26 Any time the timing cover is removed, the timing belt should be inspected for wear or damage to determine if it should be replaced. Disconnect the negative battery cables. 2. Drain all water from the system as detailed in the Maintenance section. 3. Loosen the 4 water pump pulley bolts, but do not remove the pulley. 4. Remove the power steering pump and alternator drive belt. 5. Now remove the 4 bolts and pull off the water pump pulley. 6. Remove the crankshaft pulley bolt and pulley. If difficulty is encountered, you may need to obtain a flywheel holding tool to keep the crankshaft from turning while loosening the bolt. Another method is to presoak the area with penetrating lubricant and allow it to sit overnight. A bolt which has been pretreated in this fashion will usually break loose easier. 7. Remove the front cover retaining bolts (usually 4 Allen bolts and a Phillips screw) and remove the cover. Please note that the upper Allen bolt on the starboard side is linger than the others and must be installed in the same position. To install: 8. Position the front cover on the engine. lnstall the retaining and tighten to inch Ibs. (8-12 Nm). Don't forget that the longer bolt goes in the top hole. 9. lnstall the crankshaft damper pulley and retaining bolt. Tighten the bolt to 100-120 ft. (136-163 Nm. It's not a bad idea to use a new washer here. 10. lnstall the water pump pulley and tighten the bolts to 14-21 ft. Ibs. (19-28 11. lnstall the drive belts and adjust the tension. 12. Connect the battery cables. Run the engine, check for leaks and check the ignition timing. CHECKING Crank the engine without starting it until the timing mark on crankshaft pulley lines up with the TC mark on the timing grid. 2. Pop out the rubber inspection plug found in the upper front cover and check that the camshaft sprocket marks are aligned. If not, rotate the engine another full turn and recheck it.' Front Cover I Pulley Fig. 26 Exploded view of the timing belt front cover 3-14 ENGINE MECHANICAL -FORD 4 CYLINDER ENGINES 3. If the marks are aligned in the previous step, remove the distributor cap and confirm that the rotor is pointing to the No. cylinder lead. 4. If the belt fails any of these quick check, you will need to remove it and the engine. CORRECTING AN OUT-OF-TIME ENGINE If the crankshaft pulley and camshaft sprocket timing aligned in the Checking procedures, but the distributor rotor was not pointing at the No. cylinder: Scribe a mark on the side of the distributor housing indicating the exact positioning of the cap tower for the No. cylinder's spark plug lead. 2. Pull out the high tension lead running from the ignition coil and ground it. Remove the distributor cap. 3. Remove the distributor hold-down clamp bolt and then slowly pull up on the distributor until you feel it disengage from the auxiliary shaft. 4. Rotate the rotor until it is 116th of a turn PAST the position. Insert the distributor back into the block until it is fully seated and engaged with the auxiliary shaft; you may have to wiggle the housing slightly to get everything to engage. 5. When the distributor is fully seated in the block, you should notice that the rotor rotated back around to the No. 1 position. If it did not, repeat this procedure again until it does. 6. Tighten the clamp bolt, install the cap and coil lead, and then start the engine. Check the ignition timing. If, in the Checking procedure, you were unable to the crankshaft and to perform the steps REMOVAL INSTALLATION See Figures and Disconnect the negative battery cables. 2. Remove the front cover. 3. Slide the retaining washer for the belt off of the remember that the concave side faces outward. 4. Loosen the timing belt tensioner adjustment screw, position belt tensioner tool (# or equivalent), on the tension spring roll pin and release the belt tensioner. Tighten the adjustment screw to hold the tensioner in the released position. Fig. 27 Exploded view of the timing belt and sprocket assembly SPROCKET 5. Remove the crankshaft pulley, hub and guide. 6. Remove the timing belt. If the belt is to be reused, mark the direction of rotation so it may be reinstalled in the same direction. If the belt is to be reused, inspect it for wear or damage. To install: Removing the spark plugs will make rotating the crankshaft easier. 7. Rotate the engine and position the crankshaft sprocket to align the triangular mark on the sprocket with the TDC notch on the block. 8. Position camshaft sprocket so that the timing mark aligns with the camshaft timing pointer grid. 9. Remove the distributor cap and set the rotor to the No. firing position by turning the auxiliary shaft. 10. Install the timing belt over the crankshaft sprocket and then counterclockwise over the auxiliary and camshaft sprockets. Align the belt fore-and-aft on the sprockets, but be very careful not to disturb any of the timing marks alignments. 11. Loosen the tensioner adjustment bolt to allow the tensioner to move against the belt. If the spring does not have enough tension to move the roller against the belt, it may be necessary to manually push the roller against the belt and tighten the bolt. 12. If you haven't already done so, remove a spark plug from each cylinder in order to relieve engine compression and to make sure the belt does not jump time during rotation in the next step. 13. Rotate the crankshaft two complete turns in the direction of normal rotation (clockwise when viewed from the front of the engine) to remove the slack from the belt. 14. Tighten the tensioner adjustment bolt to 28-40 ft. Ibs. (40-55 Nm) and bracket bolt to 14-22 ft. Ibs. (20-30 Nm). 15. Recheck the alignment of the timing marks. Rotate the engine two complete revolutions again and then make sure that the timing marks are all still in alignment. 16. Install the retaining washer (concave side out) and slide it onto the crankshaft. The washer is keyed to the shaft. 17. Install the front cover. 18. Install the crankshaft damper pulley and tighten the retaining bolt to 100-120 ft. 19. lnstall water pulley and tighten the bolts to 14-21 ft. (19-28 Nm). 20. Install the spark plugs. 21. Connect the battery cables. 22. Start the engine and check the ignition timing. SHAFT SPROCKET Fig. 28 Timing belt set-up SPROCKET WEBS FAC ENGINE MECHANICAL -FORD 4 CYLINDER ENGINES 3-15 REMOVAL INSTALLATION CULT See Figures 27 and 3 1. Disconnect the battery cables. 2. Remove the front cover and the timing belt. 3. Remove the camshaft and auxiliary shaft sprocket retaining bolts, as necessary. A holding tool (# is extremely helpful here. 4. Remove the crankshaft, camshaft and auxiliary shaft sprockets, as necessary, using a suitable puller. To install: 5. Install the crankshaft, camshaft auxiliary shaft sprockets, as necessary. 6. While holding the sprocket from turning (using the holding tool), tighten the camshaft sprocket retaining bolt to 80-90 ft. Ibs. Nm) the auxiliary sprocket retaining bolt to 28-40 ft. Ibs. (38-54 Nm. 7. Install the timing belt and front cover. 8. Connect the battery cables. Fig. 29 Timing belt tensioner adjustment and pivot bolts REMOVAL INSTALLATION CULT See Figures an Disconnect the battery cables. 2. Remove the front cover and timing belt. 3. Remove the timing sprocket (crankshaft, camshaft auxiliary shaft) under which the seal is being replaced. 4. Use seal remover tool or an equivalent jawed seal puller), to remove the crankshaft, camshaft auxiliary shaft Position the tool so that the jaws are gripping the thin edge of the seal very tightly. Operate the jackscrew on the tool to remove the seal. To install: 5. Lubricate the lips of the new seals with clean engine oil. 6. Use a threaded seal installer tool (# or equivalent), to install the seals. 7. Install the timing 8. Install the timing belt and front cover. 9. Connect the battery cables. Center Arbor Fig. 30 The camshaft and auxiliary shaft sprockets are most easily removed or installed using a special holding tool Fig. 31 Use a suitable tool to remove the seal . . . Fig. 32 ...or use a punch very carefully if the tool is not available I Fig. 33 You must use the tool on the crankshaft or auxiliary shaft seals 3-16 ENGINE MECHANICAL -FORD 4 CYLINDER ENGINES Fig. 34 Exploded view of the camshaft Cam Follower1 Rocker RETAINING 1 VIEW I REMOVAL INSTALLATION CULT + See Figures 32 thru 36 Depending on the available in the engine compartment, it may be necessary to raise the engine or remove it entirely in order to gain sufficient clearance when pulling out the camshaft. We recommend checking the camshaft lift prior to removing it from the cylinder block. I. Disconnect the negative battery cable and drain the cooling system. 2. Remove the cylinder head cover. 3. Remove the front cover and the timing belt. 4. Compress the valve springs using valve spring compressor lever or equivalent, and remove the cam followers (rocker arms). 5. Remove the camshaft sprocket retaining bolt and then remove the camshaft sprocket using a suitable puller. 6. Remove the camshaft seal using a seal removal tool. 7. Remove the two bolts pry off the camshaft rear retainer. 8. Remove the camshaft slowly and carefully to prevent damage to the lobes, journals or bearings. 9. Inspect the lobes and bearings for damage or wear. Replace the camshaft and bearings, as necessary. To install: 10. If camshaft bearing replacement is necessary, you will have to rent or buy a bearing removal and installation tool. Essentially the tool is a threaded rod with a pulling plate and nut, along with various size drivers to push the bearings out of or pull the bearings into position. 11. Make sure the threaded plug is in the rear of the camshaft. If you are replacing the camshaft, you may have to remove the plug from the old camshaft and install it in the new one. 12. Coat the camshaft lobes with multi-purpose grease and lubricate the journals with heavy engine oil before installation. An engine assembly lube can also be used. Carefully slide the camshaft through the bearings. 13. lnstall the camshaft rear retainer and tighten the two bolts to 6-9 Ibs. (8-12 Nm). 14. lnstall a new camshaft seal using a suitable seal installer. 15. lnstall the camshaft sprocket and tighten the retaining bolt to 80-90 ft. Ibs. (1 22 Nm). lnstall the timing belt and front cover. 17. lnstall the cylinder head cover. 18. Connect the negative battery cable, then properly refill the engine cooling system. 19. Run the engine and check for leaks. Check the ignition timing. REMOVAL INSTALLATION See Figure 37 1. Disconnect the battery cables. 2. Remove the front belt cover and the timing belt. 3. Remove the auxiliary shaft sprocket retaining bolt. Remove the sprocket using a puller. 4. Remove the distributor. 5. Remove the auxiliary shaft cover and the thrust plate. 6. Withdraw the auxiliary shaft from the block being careful not to damaae the bearinas. To 7. Dip the auxiliary shaft in engine oil before installing. Slide the auxiliary shaft into the cylinder block, being careful not to damage the bearings. 8. lnstall the thrust plate and tighten the bolts to 6-9 ft. Ibs. (8-12 Nm). 9. Position a new gasket and then install the auxiliary shaft cover. Tighten the cover screws to 6-9 ft. Ibs. (8-12 Nm). Seal ENGINE MECHANICAL -FORD 4 CYLINDER ENGINES 3-17 REMOVAL INSTALLATION See Figures and 40 1. Disconnect the battery cables and drain the cooling 2. Remove the flame arrestor. Before removing the spark plug wires, check the configuration of Fig. 35 Removing the rear retainer your engine against the firing order diagrams found in the Maintenance section. If your engine is different in any way, make notations to the Fig. 36 Slide the camshaft in from the rear I Cover 37 Exploded view of the auxiliary shaft 38 Exploded view of the cylinder head The auxiliary shaft cover and cylinder front cover share a common gasket. Cut off the old gasket around the cylinder cover and use half of the new gasket on the auxiliary shaft cover. 10. the distributor. 11. Install the auxiliary shaft sprocket and tighten the bolt to 28-40 ft. Ibs. (38-54 Nm). 12. Align the timing marks and install the timing belt and front cover. 13. Connect the battery cables. 14. Check the ignition timing. diagrams to assure proper installation. Also, be sure to tag all of the spark plug wires and the distributor cap or ignition coil terminals, as applicable. 3. Tag and remove the spark plug wires. Remove the spark plugs. 4. Remove the distributor assembly. 5. Tag and disconnect any vacuum hoses or electrical leads in the wav of head removal. 6. Remove the intake manifold assembly. 7. Remove the camshaft cover from the cylinder head. 8. Remove the front cover retaining and remove the cover. 9. Remove the timing belt from the camshaft pulley and the auxiliary pulley. Refer to the Timing Belts section. If the belt is not going to be replaced, be sure to mark the current direction of rotation on the belt to assure proper installation. 3-18 ENGINE MECHANICAL -FORD 4 CYLINDER ENGINES 10. Remove the exhaust manifold. Remove the timing belt idler and two bracket bolts. Remove the timing belt idler spring stop from the cylinder head. 12. Tag and disconnect the oil sending unit wire. 13. Remove the cylinder head bolts, then break the gasket seal and remove the cylinder head. Do not pry the cylinder head to break the gasket seal unless it is absolutely necessary. Prying the cylinder head can deform the soft metal and compromise the gasket mating surfaces. To install: 14. Clean all gasket mating surfaces and blow the oil out of the cylinder head bolt block holes. 15. Check the cylinder head for flatness using a straightedge and a feeler gauge. If the head gasket surface is warped greater than 0.006 in. it must be resurfaced. Do not grind off more than 0.010 in. from the cylinder head. Position a new cylinder head gasket on the engine. Rotate the camshaft so that the locating pin is approximately 30 degrees to the right of the 6 o' clock position when facing the front of the cylinder head (this places the pin about at the five o'clock position) to avoid damage to the valves and pistons. 17. If they are available, cut the heads off of two old cylinder head bolts to use as guide studs. Thread the studs into the engine block at opposite corners to use as guides. Make sure the gasket is properly fit to the block and then set the head into position. Apply a non-hardening gasket sealer to the bolt threads and install the bolts finger-tight. 19. Tighten the head bolts using 2 passes of the sequence as illustrated, first to 50-60 ft. Ibs. (68-81 Nm) and then to 80-90 ft. Ibs. (108-122 Nm). 20. Connect the oil sending unit wire. 21. lnstall the timing belt tensioner spring stop to the cylinder head. 22. Position the timing belt tensioner and tensioner spring to the cylinder head and install the retaining bolts. Rotate the tensioner against the spring with belt tensioner tool (# or equivalent), and temporarily tighten. 23. lnstall the exhaust manifold using a new gasket. For details, please refer to the Exhaust Manifold procedure found earlier in this section. 24. Align the distributor rotor with the No. plug location on the distributor cap and install it. 25. lnstall the timing belt over the sprockets. If the belt is not being replaced, make sure you have installed it in the same direction of rotation as it was before removal. Complete timing belt installation as detailed under the Timing Belt procedures located in this section. Be sure to check belt tension and alignment, then to properly tighten the tensioner and pivot bolts. 26. lnstall the front cover and the retaining to 6-9 ft. (8- 12 Nm). 27. lnstall the rocker arm cover and tighten the retaining bolts to 48-84 inch Ibs. 28. lnstall the intake manifold assembly. Tighten the bolts, in sequence, to inch Ibs. (6.8-9.5Nm) and then retighten them all to 14-18 ft. (19-25Nm). 29. Connect all remaining vacuum hoses and electrical leads as tagged during removal. 30. Position the alternator and install the drive belt. 31. lnstall the spark plugs, then install the spark plug wires as tagged and noted during removal. 32. lnstall the flame arrestor. 33. Connect the battery cables. 34. Bring the engine to normal operating temperature and check for leaks. 35. Check the ignition timing Fig. 39 Use locating pins when installing the head Fig. 40 Cylinder head bolt torque sequence ENGINE MECHANICAL -FORD 4 CYLINDER TORQUE Component ft. lbs. inch Ibs. Nm Auxiliary shaft Sprocket bolt 28-40 38-54 Thrust plate bolts 72-1 08 8-12 Camshaft Cover 48-84 5.5-9.5 Sprocket bolt 80-90 22 Thrust plate (retainer) 08 8-12 Connecting rod cap 30-36 40-49 Crankshaft Damper pulley 100-1 20 63 Main bearing cap 80-90 108-1 22 Cylinder head Step 50-60 68-91 Step 2 80-90 Cylinder head cover 48-84 5.5-9.5 Distributor clamp bolt 14-21 19-28 Engine coupler Flywheel 54-64 73-87 Flywheel housing 28-36 38-49 Coupler nut 14-17 19-23 Coupler ground stud 20-25 27-34 Cover 60-84 7-9 Engine mounts Front Adjusting nut 100-120 63 Bracket bolts 32-40 43-54 Lower nut 60-75 Rear Center bolt I 1989-9 Lock nut Exhaust Pipe 1987-89 14-16 1990 27-34 27-34 Flywheel Bolt 54-64 73-87 7-9 Housing 28-36 38-49 Front cover 72-108 8-12 Fuel pump 14-21 19-28 Intake manifold Step 1 60-84 7-9 Step 14-18 19-25 Main bearing cap 80-90 108-1 22 Oil M6 bolts 72-96 8-12 M8 20 11-14 Oil pump Cover bolts 72-1 20 8-14 Mounting bolts 14-21 19-28 Pick-up Tube 14-21 19-28 Oil pressure sender 12-16 16-22 Oil withdrawal tube (flare) 8 20-24 Spark plug 5-10 6.8-13.6 Timina belt 14-21 19-28 Tensioner oivot 28-40 38-54 Valve cover 48-84 5 5-9 5 Water pump (circulating pump) 14-21 19-28 Water temperature sender 12-16 16-22 ENGINE SPECIFICATIONS ENGINE SPECIFICATIONS Standard Metric Component (in.) Standard Metric Component (in.) (mm) Camshaft (mm) Valve system Clearance 0.025-0.076 Face Angle 44 deg. Wear limit 0.006 0.152 Lifter Hydraulic Hydraulic End Play 0.001-0.007 0.025-0.178 Rocker arm ratio Wear limit 0.009 0.229 (max) 0.002 0.05 Journal Diameter 1.7713-1.7720 44.99-45 Seat Angle 45 deg. Lobe Lift 0.2381 0.005 6.05 0.13 Seat Width Intake 0.060-0.080 1.52-2.03 Out or Round 0.005 0.127 Exhaust 0.070-0.090 1.78-2.29 0.005 0.127 Spring (Outer) Connecting Rod Out or Round Free length 1.89 48 Diameter 55.17-55.19 Pressure Out or Round 0.004 0.102 lntake 71-79 316-351 N Piston pin bore 0.9104-0.9112 23.12-23-14 1.56 39.62 Side Clearance Exhaust 159-175 N 0.0035-0.0105 0.089-0.267 Wear limit 0.015 0.38 1.16 29.46 0.004 0.102 Clearance .... . ..... .... Taper (max) 0.004 0.102 Intake 0.025-0.069 Crankshaft. Exhaust 0.0015-0.0032 0.038-0.081 Connecting rod diameter Crankshaft End Play 0.102-0.203 Main Bearing Journal Diameter 2.3982-2.3990 60.91-60.94 Out or round 0.0006 0.015 0.002 0.05 Wear limit 0.005 0.127 Taper (max) 0.0006 0.015 Diameter Red Piston Clearance 0.0014-0.0022 0.036 Blue 95.99-96 Piston Pin clearance 0.005 Diameter 0.91 19-0.9124 23.16-23.18 Interference Yes Yes Length 3.010-3.040 76.45-77.22 I Piston 0-0.020 0.254 Clearance 0.05-0.10 I Oil Gap 0.015-0.055 0.38-1.40 Width Snug Snug Unless noted CAMSHAFT. BEARINGS AND GEAR CHECKING REMOVAL INSTALLATION COMBINATION MANIFOLD REMOVAL INSTALLATION CYLINDER HEAD REMOVAL INSTALLATION CYLINDER HEAD (VALVE) COVER REMOVAL INSTALLATION ENGINE IDENTIFICATION ENGINE MINIMUM ENGINE HEIGHT ENGINE ALIGNMENT MODEL DESIGNATIONS REMOVAL INSTALLATION ENGINE COUPLER AND FLYWHEEL REMOVAL INSTALLATION ENGINE MECHANICAL GEAR CYLINDER HEAD ................... CYLINDER HEAD (VALVE) COVER ENGINE ENGINE COUPLER AND FLYWHEEL ... ENGINE IDENTIFICATION EXHAUST ELBOW EXHAUST HOSE (BELLOWS) EXHAUST FRONT COVER AND OIL SEAL FRONT ENGINE MOUNT GENERAL INFORMATION HARMONIC BALANCER. PULLEY AND HUB HYDRAULIC VALVE LIFTER OIL FILTER BYPASS VALVE OIL PAN OIL PUMP REAR ENGINE MOUNTS REAR OIL SEAL REAR OIL SEAL RETAINER ROCKER ARMS PUSH RODS EXHAUST ELBOW ................... REMOVAL INSTALLATION EXHAUST HOSE (BELLOWS) REMOVAL INSTALLATION EXHAUST REMOVAL EXHAUST VALVE (FLAPPER) INSTALLATION .......... REPLACEMENT ........... ..... EXPLODED VIEWS CYLINDER BLOCK CYLINDER HEAD FLYWHEEL HOUSING AND REAR MOUNTS .................... FRONT COVER AND OIL SEAL REMOVAL INSTALLATION FRONT ENGINE MOUNT REMOVAL INSTALLATION HARMONIC BALANCER. PULLEY AND HUB REMOVAL INSTALLATION HYDRAULIC VALVE LIFTER REMOVAL INSTALLATION OIL FILTER BYPASS VALVE REMOVAL INSTALLATION OIL PAN REMOVAL INSTALLATION OIL PUMP REMOVAL INSTALLATION REAR ENGINE MOUNTS REMOVAL INSTALLATION REAR OIL SEAL REMOVAL INSTALLATION REAR OIL SEAL RETAINER REMOVAL INSTALLATION ROCKER ARMS PUSH RODS REMOVAL INSTALLATION VALVE ADJUSTMENT SPECIFICATIONS ENGINE TORQUE ......................... VALVE ADJUSTMENT ENGINE MECHANICAL -GM 4 CYLINDER ENGINES The first two characters identify the engine size in liters (L); 30 represents the 25 represents the and so forth. The OMC 153 cubic inch displacement engine and the 181 cubic inch engine are manufactured by GMC and have been a favorite combination when mated to the OMC Cobra and SP stern drives. This in-line four-cylinder powerplant uses a full pressure lubrication system with a disposable flow-thru oil filter cartridge. Oil pressure is furnished by a gear-type oil pump, driven by the distributor, which is driven by a helical gear on the camshaft. A regulator on the oil pump controls the amount of oil pressure output. The oil pump scavenges oil from the bottom of the oil pan and feeds it through the oil filter and then to the main oil gallery in the block. Drilled passages in the block and crankshaft distribute oil to the camshaft and crankshaft to lubricate the rod, main and camshaft bearings. The main oil gallery also feeds oil to the valve lifters, which pump oil up through the hollow to the rocker arms to lubricate the valve train in the cylinder head. Cylinder numbering and firing orders are identified in the illustrations at the end of the Maintenance section. NEVER, NEVER attempt to use standard automotive parts when replacing anything on your engine. Due to the uniqueness of the environment in which they are operated in, and the levels at which they are operated at, marine engines require different versions of the same part; even if they look the same. Stock and most aftermarket automotive parts will not hold up for prolonged periods of time under such conditions. Automotive parts may appear identical to marine parts, but be assured, OMC marine parts are specially manufactured to meet OMC marine specifications. Most marine items are super heavy- duty units or are made from special metal alloy to combat against a corrosive salt water atmosphere. OMC marine electrical and ignition parts are extremely critical. In the United States, all electrical and ignition parts manufactured for marine application must conform to stringent Coast Guard for spark or flame suppression. A spark from a non-marine cranking motor solenoid could ignite an explosive atmosphere of gasoline vapors in an enclosed engine compartment. The engine serial numbers are the manufacturer's key to engine changes. These alpha-numeric codes identify the year of manufacture, the horsepower rating and various differences. If any correspondence or parts are required, the engine serial number must be used for proper identification. Remember that the serial number establishes the year in which the engine was produced, which is often not the year of first installation. The engine specifications decal contains information such as the model number or code, the serial number (a unique sequential identifier given ONLY to that one engine) as well as other useful information. An engine specifications decal can generally be found on top of the flame arrestor or on the side of the rocker arm cover all pertinent serial number information can be found and drive designations, serial numbers and model numbers. Unfortunately this decal is not always legible on older boats and it's also quite difficult to find, so please refer to the following procedures for each individuals unit's serial number location. Serial numbers tags are frequently difficult to see when the engine is installed in the boat; a mirror can be a handy way to read all the numbers. The engine number is sometimes also stamped on the port rear side of the engine where it attaches to the bell housing; although on most later models it may instead be a metal plate attached in the same location. If your engine has a stamped number it will simply be the serial number; if you have a plate (and you should), it will always show a Model number and then the actual Serial number. Additionally, most models will also have this plate or sticker on the transom bracket. See Figures 1,2 and 3 REMOVAL INSTALLATION The third character identifies the fuel delivery system; 2 designates a 2 bbl carburetor, 4 is a 4 bbl carburetor, and F is a fuel injected engine. The fourth character designates a major engine or horsepower change-it doesn't let you know what the change was, just that there was some sort of change. A means it is the first model released, B would be the second, and so forth The fifth character designates what type of steering system was used; M would be manual steering and P would be power steering. Now here's where it gets interesting; on engines and 1994-98 engines, the sixth, seventh and eighth characters designate the model year. The sixth and seventh actually show the model year, while the eighth is a random model year version code. KWB and WXS represent 1986; and ARJ, ARF, FTC, SRC or SRY show 1987. MDA is 1994, HUB is 1995, NCA is 1996, LKD is 1997 and BYC is 1998. On 1988-93 engines, the sixth character designates the direction of propeller rotation. R is right hand, L is left hand and E is either. Also on engines, the seventh, eighth and ninth characters designate the model year. The seventh and eighth actually show the model year, while the ninth is a random model year version code. GDE or GDP is 1988, MED or MEF is 1989, PWC, PWR or PWS is 1990, RGD or RGF is 1991, AMH or AMK is 1992 and JVB or JVN is 1993. Any remaining characters are proprietary. So in example, a Model number on the ID plate that reads would designate a 1987 engine with a 2 bbl carburetor and manual steering, first model released. Engine Model Designations All engines covered here utilize unique identifiers assigned by OMC; surnames if you will-2.3, etc. Obviously the first two characters designate the engine size in litres (L). The second letter, a G or and F designate the engine manufacturer; General Motors (G) or Ford (F). The third through fifth letters can be found in different combinations, but the individual letter designates the same thing regardless of position. L designates limited output. S and X designate superior output-a will always have a lesser horsepower rating than a in a given model year; a will be less than a i designates that the engine is fuel injected, if there is no then you know the engine uses a carburetor. CULT +See Figures 4 thru 10 Prior to removing the engine from your vessel, it is imperative to measure the engine height as detailed in the Determining Minimum Engine Height section on 1995-98 engines. DO NOT remove the engine until you have completed this procedure! 1. Check the clearance between the front of the engine and the inside edge of the engine compartment bulkhead. If clearance is less than 6 in. you will need to remove the stern drive unit because there won't be enough room to disengage the driveshaft from the engine coupler. More than 6 in. will provide enough working room to get the engine out without removing the drive, BUT, we recommend removing the drive anyway. If you intend on doing anything to the mounts or stringers, you will need to re-align the engine as detailed in the Engine Alignment section-which requires removing the drive, so remove the drive! 2. Remove the stern drive unit as detailed in the Drive Systems section. 3. Open or remove the engine hatch cover. 4. Disconnect the battery cables (negative first) at the battery and then disconnect them from the engine block and starter. Make sure that all switches and systems are OFF before disconnecting the battery cables. ENGINE MECHANICAL -GM 4 CYLINDER ENGINES 4-3 Model Year Designation: Randomly chosen PRAMH King Model Year Version: Randomly chosen for each major non-interchangeable Fig. 1 Decoding the engine model number is easy I I Fig. 2 Engine serial number engines engine 5. Disconnect the two power steering hydraulic lines at the steering cylinder (models steering). Carefully plug them and then tie them off somewhere on the engine, making sure that they are higher then the pump to minimize any leakage. 6. Disconnect the fuel inlet line at the fuel pump or filter (whichever comes first on your particular engine) and quickly plug it and the inlet-a clean golf tee and some tape works well in this situation. Make sure you have rags handy, as there will be some spillage. 7. Tag and disconnect the two-wire connector. 8. Pop the two-wire sender connector out of the retainer and then disconnect it. You may have to cut the plastic tie securing the cable in order to move it out of the way. Fig. 3 You should also be able to find a plate on the transom bracket 9. Locate the large rubber coated instrument cable connector (should be on the starboard side), loosen the hose clamp and then disconnect it fron the bracket. Move it away from the engine and secure it. On early models, you will also need to unplug the three-wire cable connector just above it. note of your throttle arm attachment stud-is it a close" or a "pull-to-close"? 10. Remove the cotter pin and washer from the throttle arm. Loosen the anchor block retaining nut and then spin the retainer away from the cable trunnion. Remove the throttle cable from the arm and anchor bracket. Be sure to mark the position of the holes that the anchor block was attached to. 4-4 ENGINE MECHANICAL -GM 4 CYLINDER ENGINES Fig. 4 Disconnect the power steering lines at the cylinder I Fig. 5 Locate the engine lifting brackets ... Anchor Block Cotter Pin Bracket Fig. 6 Disconnect the instrument cable Fig. 7 ...and then connect and engine hoist connector I 11. Loosen the hose clamps (4) and disconnect the exhaust elbow bellows from elbow. You may want to spray some WD-40 around the lip of the hose where it connects to the elbow, grasp it with both hands and wiggle it back and forth while pulling down on it. 12. Drain the cooling system as detailed in the Maintenance section. 13. Loosen the hose clamp on the water supply hose at the transom bracket and carefully slide it off the water tube. Attach the hose to the engine. 14. Disconnect the shift cables and position them out of the way. 15. Tag and disconnect any remaining lines, wires or hoses at the engine. 16. Attach a suitable engine hoist to the lifting eyes (usually front starboard side, rear port side) and take up any line slack until it is just taught. The engine hoist should have a capacity of at least 1500 Ibs. (680 17. Locate the rear engine mounts and remove both lock nuts and flat washers. 18. Locate the front engine mount and remove the two lag bolts. 19. If you listened to us at the beginning of the procedure, the drive unit should be removed. If so, slowly and carefully, lift out the engine. Try not to hit the power steering control valve, or any other accessories, while removing it from the engine compartment. If you didn't listen to us, and you had sufficient clearance in the engine compartment, the drive unit is probably still installed. Raise the hoist slightly until the weight is removed from the mounts and then carefully pull the engine forward until the driveshaft disengages from the coupler, now raise the engine out of the compartment. To install: 20. Apply Engine Coupler grease to the splines of the coupler. 21. Slowly lower the engine into the compartment. If the drive unit was not removed, AND the crankshaft has not been rotated, insert the driveshaft into the coupler as you push the engine backwards until they engage completely and then lower the engine into position over the rear mounts until the front mounts just touch the stringers. If the shaft and coupler will not align completely, turn the crankshaft or driveshaft slightly until they mate correctly. If the drive was removed, or the mounts were disturbed in any way, lower the engine into position over the rear mounts until the front mount just touches the stringer. 22. Install the two flat washers into the recess in the engine bracket side of the rear mounts and then install the two lock nuts. Tighten them to 28-30 ft. Ibs. (38-40 Nm). Never use an impact wrench or power driver to tighten the locknuts. 23. Install the lag bolts into their holes on the front mounts and tighten each bolt securely. 24. If the drive was removed, the mounts were disturbed or the didn't mate correctly, perform the engine alignment procedure detailed in this section. We think it's a good idea to do this regardless! After you've performed the alignment procedure, make sure that you hold the top adjusting nut and tighten the lower nut on the mount to 115- ft. Ibs. (1 Nm). 25. Reconnect the exhaust bellows by sliding it up and over the elbow, position the clamps between the ribs in the hose and then tighten the clamps securely. Make sure you don't position the clamps into the expanding area. 26. Reconnect the water inlet hose. Lubricate the inside of the hose and wiggle it onto the inlet tube. Slide the clamp over the ridge and tighten it securely. This sounds like an easy step, but it is very important-if the hose, particularly the underside, is not installed correctly the hose itself may collapse or come off. Either scenario will cause severe damage to your engine, so make sure you do this correctly! 27. Carefully, and quickly, remove the tape and plugs so you can connect the power steering lines. Tighten the large fitting to 15-17 ft. Ibs. (20-23 Nm) and the small fitting to 10-12 Nm). Don't forget to check the fluid level and bleed the system when you are finished with the installation. 28. Reconnect the connector so the two halves lock together. 29. Reconnect the trim position sender leads, the instrument cable, the engine ground wire, the battery cables and all other wires, lines of hoses that were disconnected during removal. Make sure you swab a light coat of grease around the fitting for the large cable plug. ENGINE MECHANICAL -GM 4 CYLINDER ENGINES 4-5 Boss \ Groove Trunnion Fig. 9 Details of the throttle cable and trunnion Trunnion Anchor Block Retaining Fig. 10 Attach the anchor block assembly to the bracket Always make certain that all switches and systems are turned OFF before reconnecting the battery cables. Make sure all cables, wires and hoses are routed correctly before initially starting the engine. 30. Unplug the fuel line and fitting and reconnect them. Remember to check for leaks as soon as you start the engine. 31. Install and adjust the throttle cable. For complete details, please refer to the Fuel System section): a. Remember we asked you to determine if you had a "push-to-close" or "pull-to-open" throttle cable (the throttle arm stud)? Position the remote control handle in Neutral-the propeller should rotate freely. b. Turn the propeller shaft and the shifter into the forward gear detent position and then move the shifter back toward the Neutral position halfway. c. Position the trunnion over the groove in the throttle cable so the internal bosses align and then snap it into the groove until it is fully seated. d. lnstall the trunnionlcable into the anchor block so the open side of the trunnion is against the block. Position the assembly onto the bracket over the original holes (they should be the lower two of the four holes) and then install the retaining bolt and nut. When the nut is securely against the back of the bracket, tighten the bolt securely. e. lnstall the connector onto the throttle cable and then pull the connector until all end play is removed from the cable. Turn it sideways until the hole is in alignment with the correct stud on the throttle arm. Slide it over the stud and install the washer and a new cotter pin. Make sure the cable is on the same stud that it was removed from. Tighten the jam nut against the connector On 1995-98 engines, the throttle arm connector nut must be installed on the cable with a minimum of 9 turns-meaning that at least 114 in. of thread should be showing between the end of the cable and the edge of the nut. 32. lnstall and adjust the shift cables. Please refer to the Drive Systems section for further details. 33. Check and refill all fluids. Start the engine and check for any fuel or coolant leaks. Go have fun! MINIMUM ENGINE HEIGHT 1995-98 Engines See Figure 11 This procedure MUST be performed prior to removing the engine from the vessel. With the engine compartment open, position a long level across the transom running fore and aft. 2. Have a friend or assistant steady the level while you measure from the bottom edge of the tool to the top of the exhaust elbow. Record the distance as "1". 3. Now measure from the bottom of the level to the static water line on the drive unit. Record the distance as 4. Subtract the elbow measurement (1) from the static waterline measurement (2). If the result is less than 9 in. an exhaust elbow high rise kit must be installed (available from your local parts supplier). ENGINE ALIGNMENT CULT See Figures 12 and Engine alignment is imperative for correct engine installation and also for continued engine and drive operation. It is a good idea to ensure proper alignment every time that the drive or engine have been removed. Engine alignment is checked by using OMC alignment tool and handle (Volvo and Engine alignment is adjusted by raising or lowering the front engine With the drive unit off the vessel, slide the alignment tool through the gimbal bearing and into the engine coupler. It should slide easily, with no binding or force. If not, check the gimbal bearing alignment as detailed in the Drive Svstems section. If bearina alianment is correct, move to the next step. 2. your engine utilizes a on the bottom of the mount bolt, loosen it and back it off at least 112 in. 3. Loosen the lock nut and back it off. 4. Now, determine if the engine requires raising or lowering to facilitate alignment-remember, the alignment tool should still be in position. or loosen the adjusting nut until the new engine height allows the alignment tool to slide freely. 5. Hold the adjusting nut with a wrench and then tighten the lock nut to 115-140 ft. Ibs. (156-190 Nm). If your engine uses a jam nut, cinch it up against the lock nut. 6. Remove the alignment tool and handle. Fig. Use a level to determine minimum engine height 4-6 ENGINE MECHANICAL -GM 4 CYLINDER ENGINES Fia. 12 lnstall the alianment tool through the aimbal bearing 1 Lag bolts and flat washers Fig. 13 A good view of the front engine mount-not all engines utilize the iam nut REMOVAL INSTALLATION CULT 1. Remove the engine as previously detailed. 2. Loosen the two bolts and remove the mount from the transom plate. 3. Hold the square nut with a wrench and remove the shaft bolt. Be sure to take note of the style and positioning of the two mount washers as you are removing the bolt. Mark them, lay them out, or write it down, but don't forget their orientation!! To install 4. Slide the lower of the two washers onto the mount bolt, exactly as it came off. 5. Slide the bolt the flat side of the rubber mount, install the remaining washer (as it came off!) and then spin on the square nut. Do not tighten it yet. Incorrect washer installation will cause excessive vibration during engine operation. 6. Turn the assembly upside down and clamp the nut in a vise. Spin the assembly until the holes in the mounting plate are directly opposite any two of the flat sides on the nut. This is important, otherwise the slot on the engine pad will not engage the mount correctly. Secure the mount in this position and tighten the bolt to 18-20 ft. Ibs. (24-27 Nm) on 1986-88 engines, or 44-52 ft. Ibs. (60-71 Nm) on 1989-98 engines. 7. Remove the mount from the vise and position it on the transom plate. lnstall the bolts and washers and tighten each to 20-25 ft. Ibs. (27-34 Nm). 8. Install the engine, making sure that the slot in the engine pad engages the square nut correctly. Install the two washers and locknut and tighten it to 28-30 ft. Ibs. (38-41 Nm). REMOVAL INSTALLATION 1. Open or remove the engine compartment hatch. the negative battery cable. 2. Loosen the clamp and remove the crankcase ventilation hose at the cover (if equipped). Carefully move it out of the way. 3. Tag and disconnect the shift cut-out switch leads at the terminal block. 4. If your engine has a spark plug wire retainer attached to the cover, the wires or remove the retainer. REMOVAL INSTALLATION See Figure 13 1 an engrne over the engrne and hook the two eyes 2 Remove the two lag bolts on each srde of the mount where rests on the stringer 3 the engine just enough to allow room for the mount 4 Remove the four bolts with lock washers and out the mount Don't forget the spacer on the port side 5 Measure the between the bottom of the large washer on the lower side of the bracket and the upper side of the smaller washer on top of the mount Record 6 an open end wrench over the shaft just underneath the bracket to hold the shaft and then remove the top nut off the bracket and the spacer 7 Remove the two bolts the rubber mount to the upper bracket and remove 8 Remove the lower lock nut from the shaft and lift the shaft out of the lower mount Some may have a jam nut under the locknut To install: 9 Drop the adjustrng shaft the lower mount and on the lower locknut until fingertrght 10 the spacer over the top end of the shaft 11 the rubber mount back the upper bracket and the bolts to 30-35 ft Ibs (41-47 Nm) 12 the upper bracket over the shaft and then tighten the upper nut to 50-60 ft Ibs (68-81 Nm) 13 the assembly onto the engrne, hold the spacer place and install the two long bolts on the port srde lnstall the two shorter bolts the starboard We suggest new lock washers here Trghten the long bolts to 48-56 ft Ibs (65-76 Nm) and the short bolts to 32-40 ft Ibs (43-54 14 the measurement you took earlier and check now Loosen the lower locknut and rotate the shaft you achieve the correct between the two washers Once done, up the lower locknut the lower surface of the lower mount and then tighten the adjusting nut to 11 ft Ibs (1 Nm) 15 the mount over the lag screw holes and then slowly lower the engine all is off the hoist Install and tighten the lag screws securely 16 If you're confident that your measurements and subsequent adjustment place the exactly where was prror to removal, then you are through If you're us though, you may want to check the engine before you frre up the engrne ENGINE MECHANICAL -GM 4 CYLINDER ENGINES 5. Remove the fuel line at the pump and plug it, and the fitting, to avoid spills and system contamination. Remove the overflow hose also, plugging it and moving it out of the way, Have some rags nearby, as there will be some seepage either way. Move the line out of the way of the cover. 6. Remove the circuit breaker bracket and carefully position it out of the way. 7. Loosen the cover mounting bolts and lift off the cylinder head cover. Take note of any harness or hose retainers and clips that might be attached to certain of the mounting bolts; you need to make sure they go back in the same place. To install: 8. Clean the cylinder head and cover mounting surfaces of any residual gasket material with a scraper or putty knife. 9. Position a new gasket on the cylinder head and then position the cover (don't forget the J-clips!). Tighten the mounting bolts to 45 inch Ibs. (5 Nm) on 1986-93 engines, or 65 inch Ibs. (7.3 Nm) on 1994-98 engines. Make sure anv retainers or clips that were removed are back in their positions. 10. Reconnect the fuel line to the pump. Check for leaks now, and after you restart the engine. 11. Connect the crankcase ventilation hose and the cut-out switch leads. Check that there were no other wires or hoses you may have repositioned in order to gain access to the cover. 12. Connect the battery cables. REMOVAL INSTALLATION See Figure 14 1. Open or remove the engine hatch cover and disconnect the negative battery cable. Remove the cylinder head cover as detailed previously. 2. Bring the piston in the No. 1 cylinder to TDC. If only one arm, bring the piston in that cylinder to TDC. The No. cylinder is the first cylinder at the front of the engine. 3. Loosen and remove the rocker arm nuts and lift out the balls. Lift the arm itself off of the mounting stud and pull out the It is very important to keep each cylinder's component parts together as an assembly. We suggest drilling a set of holes in a holes. and positioning the pieces in the To install: 4. Clean and inspect the rocker assemblies. 5. Coat all bearing surfaces of the rocker assembly with engine oil. 6. Slide the rods into their holes. Make sure that each rod seats in its socket on the lifter. 7. Position the rocker arm over the stud so that the cupped side rides on the push rod. Slide the ball over the stud, install the nut and tighten it securely, or until all play in the push rod is taken up. 8. Adjust the valves and install the cylinder head cover. 9. Connect the battery cable and check the idle speed. Fig. 14 Exploded view of the rocker arm assembly VALVE ADJUSTMENT See Figure 15 OMC recommends adjusting the valves while the engine is cold and while the engine is OFF. These engines utilize hydraulic valve lifters, although there is no need for periodic valve adjustment, it is necessary to perform a preliminary adjustment after any work on the valve assembly. All adjustment should be undertaken while the lifter is on the base circle of the camshaft lobe for that particular cylinder. This means the opposite side of the pointy part of each lobe. Rotate the crankshaft, or bump the engine with the starter until the No. 1 cylinder is at TDC of the compression stroke-remember, this is the first cylinder at the front of the engine). Both lifters should be on the base circle of the camshaft. Note that the notch or mark on the damper pulley will be lined up with the mark on the timing scale. Be careful here though, this could mean that either the No. 1 or the No. 4 piston is at TDC. Place your hand on the No. 1 cylinder's valve and check that it does not move as the mark on the pulley is approaching the mark on the tab. If it does not move, you're ready to proceed; if it does move, you are on the No. 4 cylinder and need to rotate the engine an additional full turn This is important so make sure you've gotten it right! Another method is to mark the position of the No. 1 cylinder's terminal on the distributor; do this on the body of the distributor because you're about to remove the cap. Remove the distributor cap and bump the engine over with the starter until rotor points to the mark you made previously for the No. 1 cylinder terminal. Once again, you're at TDC on the compression stroke. 2. Now that the No. cylinder is at TDC, you can adjust both valves. Loosen the adjusting nut on the rocker until you can feel lash (play in the push rod) and then tighten the nut until the lash has been removed. Carefully jiggle the push rod while tightening the nut until it won't move anymore-this is zero lash. Tighten the nut an additional full turn to set the lifter and then you're done. Perform this procedure on each of the valves for this cylinder. 3. Perform the first two on the remainina cylinders in the proper order (2-4, front to back), setting the respective each TDC. Fig. 15 Wiggle the push rod slowly while tightening the rocker adiustina nut ENGINE MECHANICAL -GM 4 CYLINDER ENGINES REMOVAL INSTALLATION DERATE Remove the cylinder head cover. 2. Usina air, thorouahlv cle the cylinder and If compressed air is not available, we highly recommend that you DO NOT proceed with this procedure. It is EXTREMELY important that no dirt gets into the lifter recesses before completing the installation. 3. Loosen the rocker arms and pivot the rockers off of the pushrods. 4. Disconnect the spark plug wires at the plugs. 5. Remove the high tension lead at the coil. Tag and disconnect both electrical connectors and then remove the coil and its bracket from the cylinder head. 6. Remove the distributor cap and mark the position of the rotor on the body of the distributor housing. Matchmark the distributor housing to the cylinder block and then remove the distributor, covering the hole carefully. 7. Remove the cover and gasket from the side of the cylinder block. On most later models, this will require removing the shift bracket assembly and moving it 8. Remove the and lifters from the block, being very careful to keep track of where each one came from. Once again, we suggest using a 2x4 with holes drilled in it to store the rods and lifters; you'd be amazed at how quickly this job will fall apart if someone walks in and kicks the components that you have laid out on the floor! To install: Inspect the camshaft contact surface on the bottom of each lifter for excessive wear, galling or other damage. Discard the lifter if any of the above conditions are found. You'll probably also want to check out the camshaft lobe for damage also. 10. Coat the bottom of each lifter with and then carefully install each one into its recess. lnstall the and then install the cover with a new gasket. Tighten the retaining bolts securely. If you removed the shift bracket previously, install it now. lnstall the distributor so the marks on the housing and block are in alignment. Confirm that the rotor orientation mark made on the housing still aligns with the direction that the rotor is pointing. If not, or if the engine has been rotated for some reason during this procedure, please refer to the Ignition System section for complete details. 13. lnstall the distributor cap. 14. lnstall the coil and its bracket. Reconnect all plug wires and electrical leads. 15. Move the rockers into position and then adjust the valve lash as detailed previously. 16. lnstall the cylinder head cover. If any, or all, of the lifters has been replaced with a new one it is very important that you add GM Engine Oil Supplement to the crankcase BEFORE starting the engine. These engines incorporate the intake and exhaust manifolds into one unit called a combination manifold. It is serviced as a unit. REMOVAL INSTALLATION See Figure 16 DERATE 1. Open or remove the engine compartment hatch. the negative battery cable. 2. Drain all water from the engine, manifold and exhaust elbow as detailed in the Maintenance section. 3. Remove the flame arrestor and set it aside. 4. Disconnect the throttle cable from the carburetor, remove the anchor bolt and position the cable out of the way. Mark which anchor stud the cable was attached to for installation. 5. Disconnect the fuel line at the carburetor and fuel pump. Plug the pump inlet fitting. Make sure you have some rags handy to mop up the inevitable spill. 6. Remove the carburetor as detailed in the Fuel System section. 7. Remove the crankcase ventilation hose. Tag and disconnect any vacuum or electrical lines and then remove the carburetor. 8. Disconnect the shift cables. 9. Disconnect the water inlet line from the thermostat housing. 10. Remove the alternator and its mounting bracket as detailed in the Charging System section. On certain early engines without power steering, it may not be necessary to remove the alternator. Tag and disconnect any wires or hoses that may interfere with manifold removal. 12. Loosen the clamps and slide the exhaust pipe bellows off of the high rise elbow. Remove the mounting bolts (or nuts) and lift the elbow off of the manifold along with the throttle linkage plate. 13. If equipped, remove the oil cooler and mounting bracket. 14. Loosen and remove the manifold mounting bolts (4) and nuts (2) from the center outward and remove the manifold from the cylinder you may have to provide a little friendly persuasion. To install: 15. Carefully clean all residual gasket material from the head, manifold and elbow mating surfaces with a scraper or putty knife. lnspect all gasket surfaces for scratches, cuts or other imperfections. 16. Position a new gasket on the cylinder head and install the manifold; making sure that everything is aligned properly. Tighten all until are just tight and then torque them to ft. Ibs. (27-34 Nm), starting in the center and alternately working your way out to the ends of the manifold. 17. Position a new gasket coated with sealer on the manifold, making sure that the indents line up and then install the elbow. You may also have an additional gasket and a restrictor plate on some models. Tighten the mounting to 12-14 ft. Ibs. Nm). Connect the exhaust pipelbellows and tighten the clamps securely. 18. Connect the water inlet line and the shift cables. 19. lnstall the carburetor with a new gasket and reconnect the throttle cable, choke wire and any vacuum lines. Remember which anchor stud the throttle was attached to. 20. Connect the fuel line to the carb and the fuel pump (remember to unplug the pump fitting) and then install the flame arrestor. 21. lnstall the alternator; tighten the alternator and bracket bolts to 26-30 ft. Ibs. (35-41 Nm). lnstall the oil cooler if removed. 22. Make sure that any lines or hoses that you may have moved or disconnected during removal are reconnected and routed properly. 23. Fill the system with water, connect the battery cable and start the engine. When the engine reaches normal operating temperature, turn it off and re-torque the manifold bolts. REMOVAL INSTALLATION See Figure 16 1. Drain the cooling system. 2. Loosen the hose clamps and slide off the exhaust hose (bellows). 3. Reach into the open end of the elbow and loosen the hose clamp to disconnect the coolant hose if so equipped. Remove the hose and fitting, positioning them out of the way. 4. Disconnect the throttle cable from the arm and anchor bracket. Position it out of the way. 5. Remove the two bolts or nuts on the forward side of the elbow mating flange and swing the throttle cable anchor bracket out of the way. 6. Remove the two and washers from the rear side of the elbow and lift it off the manifold. A little friendly persuasion with a soft rubber mallet may be necessary! Be careful though, no need to take out all your aggressions on the poor thing. 7. Remove the and restrictor plate (if equipped). You can throw away the but keep the plate if your engine uses it. ENGINE MECHANICAL -GM 4 CYLINDER ENGINES 4-9 Manifold 16 Exploded view of the manifold, elbow and exhaust pipe 8. Clean elbow coat both sides of a new with Gasket Sealing compound and REMOVAL INSTALLATION onto the manifold flange. 9. If your engine was so equipped, position the restrictor plate second gasket onto the manifold. Don't forget to coat the gasket with sealing comoound. 10 the elbow on the the anchor bracket and 1. Loosen all four hose clamps, two on top of the hose and two on the screw the two Install the two bottom new lock washers and then all four to 12-14 Ibs (16-19 Nm) 2 a soapy water over the top of hose where mates11 Connect the coolant hose the elbow and the clamp the exhaust elbow and let for a 12 the exhaust hose, all the way onto the elbow 3 Grasp the hose both hands and and the clamp screws securely down on separates from the elbow. 13 Reconnect the throttle cable 4 Now upwards off the exhaust Make sure secure the pipe while off the hose. 4-10 ENGINE MECHANICAL -GM 4 CYLINDER ENGINES 5. Check the hose for wear, cracks and deterioration. 6. Coat the inside of the lower end of the hose with soapy water and wiggle it into position on the pipe. Remember to install the two clamps before sliding it over the end of the pipe. There are usually two ribs on one end of the hose--this is the side that attaches to the exhaust elbow. Do not position this end onto the exhaust pipe. 7. Slide two clamps over the upper end (the side with two ribs!), lubricate the inside with soapy water and wiggle the hose over the elbow until it is in position. 8. Tighten all four clamps securely. REMOVAL INSTALLATION See Figure 16 1. It is unlikely you will be able to get the pipe off the engine, so remove the engine as previously detailed. 2. Loosen the four retaining bolts at the transom shield and then remove the exhaust pipe. Carefully scrape any remnants of the seal from the pipe and transom mounting surfaces. The pipe mounting holes in the transom shield utilize locking inserts. NEVER clean the holes or threads with a tapping tool or you risk damaging the locking feature of the threads. 3. Coat a new seal with OMC Adhesive M or 3M Scotch Grip Rubber Adhesive and position it into the groove on the transom shield mating surface. 4. Coat the mounting bolts with Gasket Sealing Adhesive. Position the exhaust pipe, insert the bolts and tighten them to 10-12 ft. Ibs. (14-16 Nm) on 1986-89 engines; or 20-25 ft. Ibs. (27-34 Nm) on 1990-98 engines. Make sure that the lines are routed correctly (above and behind) before tightening the pipe to the transom. 5. lnstall the engine. EXHAUST VALVE (FLAPPER) REPLACEMENT 1. Remove the exhaust hose from the elbow and The flapper is located in the upper end of the pipe. 2. The valve is held in place by means of a pin running through two bushings in the sides of the pipe. Position a small punch over one end of the pin and carefully press the pin out of the pipe. Make sure you secure the valve while removing the retaining pin so it doesn't fall down into the exhaust pipe. 3. Press out the two bushings and discard them. Coat two new bushings with Scotch Grip Rubber Adhesive and press them back into the sides of the pipe. 4. Position the new valve inio the pipe with the long side DOWN. When looking at the valve, the molded retaining rings are off-center-the side with the rings should face the top of the pipe. When the valve is in place, coat the pin lightly with engine oil and slowly slide it through one of the bushings, through the two retaining holes on the valve and then through the opposite bushing. Make sure the pin ends are flush with the sides of the pipe on both sides. 5. lnstall the exhaust hose. REMOVAL INSTALLATION 4 See Figure 20 CULT More times than not this procedure will require the removal of the engine. Your boat and its unique engine installation will determine this, but the procedure is almost always easier with the engine removed from the boat. Remove the engine as previously detailed in this section. 2. If you haven't already drained the engine oil, do it now. Make sure you have a container and lots of rags available. 3. Remove the starter motor as detailed in the Electrical section. Although not absolutely necessary, this step will make the job much easier. 4. Remove the oil withdrawal tube from the oil drain plug fitting. 5. Loosen and remove the oil pan retaining bolts and nuts, starting with the center bolts and working out toward the pan ends. Lightly tap the pan with a rubber mallet to break the seal and then lift it off the cylinder block. If your engine stand will allow for rotating the engine, you'll find that this will be easier with the pan facing up. To install: 6. Clean the pan mating surfaces of any residual gasket material with a scraper or putty knife. Make sure that no old gasket material has been pressed into the retaining bolt holes in the pan, block or front cover. Clean the pan itself thoroughly with solvent. 7. Coat a new gasket with RTV sealant and then position the gasket onto the pan being very careful to line up all the holes. 8. Move the pan and gasket onto the block. It is very important that you ensure all the holes line up correctly; sometimes a few bolts inserted through the pan and gasket will help the gasket stay in place. 9. lnstall all bolts and nuts finger tight and then tighten the bolts to 80 inch Ibs. (9 Nm) and the bolts to 165 inch (19 Nm). Remember, on all engines, to with the center bolts and work outward toward the ends of the pan. 10. lnstall the oil drain fitting and finger tighten the bolt. Rotate the fitting and then attach the withdrawal tube. Tighten the fitting bolt and flare nut to 15-18 ft. Ibs. Nm). lnstall the starter motor and then install the engine (if removed). Run the engine up to normal operating temperature, shut it off and check the pan for any leaks. Fig. 17 Loosen the upper clamp screws and wiggle the bellows off of the elbow ... Fig. 18 ...loosen the lower clamp screws and then pull it off of the exhaust pipe Fig. 19 Be sure that the bellows end with two ribs is on top ENGINE MECHANICAL -GM 4 CYLINDER ENGINES Fig. 20 The oil pan uses a one-piece soft rubber gasket The two-piece oil pump utilizes two pump gears and a pressure relief valve. A baffled pick-up tube is press-fit into the body of the pump. The pump is driven via the distributor shaft which is itself driven from a gear on the camshaft. REMOVAL INSTALLATION See Figure 21 1. Remove the oil pan as previously detailed. you probably need to remove the engine for this procedure. 2. Loosen and remove the tube bracket bolt. The tube is pressed into the pump not'be removed unless replacement is necessary. 3. Loosen and remove the two pump mounting bolts and lift off the pump assembly. 4. Check that the pump and block mating surfaces are clean and then position the pump over the block so that the pump drive shaft slot is aligned with the distributor tang. Make sure that the flange covers the alignment bushing. Do not use a gasket or RTV sealant. 5. Tighten the pump mounting bolts to 110-120 inch Ibs. (12-14 Nm). Position the tube bracket and tighten the bolt to 60 inch (7 6. the oil pan and engine. Pump Housing Gears Pump .Housing Screen Fig. 21 Exploded view of the oil pump After removing the oil filter, check the spring and small fiber valve for proper operation. Any signs of incorrect operation, or wear and deterioration will necessitate replacement. REMOVAL INSTALLATION Drain the oil as detailed in the Maintenance section. 2. Remove the oil filter. 3. Using a small remove the valve. 4. lnstall a new valve and press it in by placing a 9116 in. deep socket over it and tapping the socket lightly with a hammer. 5. lnstall the oil filter and refill the engine with the appropriate oil. REMOVAL INSTALLATION See Figures and 24 1 Remove the engine from the boat as detailed previously in this section. 2. Although not strictly necessary, we recommend removing the starter. 3. Remove the 4 or 5 mounting bolts and slide out the flywheel housing cover. 4. Loosen and remove any connections attached to either of the ground studs on each side of the flywheel. Move the electrical leads out of the way. 5. Remove the ESA bracket and position it out of the way on early models. On later models, remove the mounting bolts for the 10-pin connector and relay, and then move the bracket out of the way. 6. Cut the plastic tie that secures the housing drain hose (if equipped) and the pull the hose out of the fitting. 7. Loosen the remaining retaining bolts (some of which were already removed with the shift bracket) for the flywheel housing and remove it. Take note of the positioning of any clamps so they may be installed in the same position. 8. Slide a wrench behind the coupler and loosen the six flywheel mounting nuts gradually and as you would the lug nuts on your car or truck- that is, in a diagonal star pattern. 9. Remove the coupler and then the flywheel. To install: Thoroughly clean the flywheel mating surface and check it for any nicks, cracks or gouges. Check for any broken teeth. Install the over the dowel on the crankshaft. 12. Slide the coupler over the studs so that it sits in the recess on the flywheel. lnstall new lock washers and tighten the mounting bolts to 40-45 ft. Ibs. (54-61 Nm). Once again use the star pattern while tightening the bolts. 13. Position the flywheel housing and the shift bracket. Make sure that the clamps are in their original positions and insert the mounting bolts. Tighten them to 28-36 ft. Ibs. (38-49 Nm). lnstall the washer, lock washer and inner nut on the ground stud and tighten it to 20-25 ft. Ibs. (27-34 Nm) on 1986-93 engines, or 35-40 ft. (47-54 Nm) on 1994-98 engines. Attach the electrical leads, install another lock washer and then tighten the outer nut securely. 15. Slide the lower flywheel cover into place and tighten the bolts to 60- 84 inch Ibs. (7-9 Nm). 16. Attach the drain hose with a new plastic tie. 17. lnstall the starter and engine. REMOVAL INSTALLATION Two Piece Oil (1986-90) + See Figures and 27 These engines utilize a two-piece rear main seal. The seal can be removed without removing the crankshaft. You will need to remove the engine for this procedure though. Remove the engine as detailed previously in this section. 4-12 ENGINE MECHANICAL -GM 4 CYLINDER ENGINES one seal. 3. Loosen the retaining bolts and remove the rear main bearing cap. Carefullv insert a small and remove the lower half of the seal from the cap. damage the seating surface, Using a hammer and a small drift, tap on the end of the upper seal until it starts to protrude form the other side of the race. Grab the protruding end with pliers and pull out the remaining seal half. 25 Drive out the old upper seal with a small 5. Check that you have the correct new seal. Seals with a hatched inner surface can only be used on left hand rotation engines, smooth seals can be used on any engine. Coat the lip and bead thoroughly with motor oil. Keep oil away from the seal parting surfaces. 6. Your seal kit should come with an installation tool, if not, take a 0.004 in, feeler gauge and cut each side back about a half inch so that you're left with an 11164 inch point. Bend the tool into the gap between the crankshaft and the seal seating surface. This will be your "shoe horn". 7. Position the upper half of the seal (lip facing the engine) between the crank and the tool so that the seal's bead is in contact with the tool tip. Roll the seal around the crankshaft using the tool as a guide until each end is flush with the cylinder block. Remove the tool. 8. Insert the lower seal half into the main bearing cap with the lip facing the cap. Start it so that one end is slightly below the edge of the cap and then use the tool to shimmy the seal all the way in until both edges are flush with the edge of the cap. Remove the tool. Feeler Gauge ..... I Cut away Fig. 26 Fabricate a seal installation tool out of an old feeler gauge ... 1 Installation tool 2-Seal 3-Engine block 4-Crankshaft Fig. 27 ...and then use the tool to feed the seal around the crankshaft ENGINE MECHANICAL -GM 4 CYLINDER ENGINES 4-13 I Fig. 28 Use the three slots in the seal retainer when removing the rear main I 9. Make sure that the mating surfaces and the seal ends are free of any oil and then apply a small amount of Perfect Seal to the block just behind where the upper seal ends are. 10. lnstall the bearing cap and tighten the bolts to 10-12 ft. Ibs. (14-16 Nm). Tap the end of the crankshaft forward and backward (as detailed in the appropriate section) and then tighten the bolts to 60-70 ft. Ibs. (82-94 Nm). 11. lnstall the oil pump and pan. 12. lnstall the engine. One Piece Oil Seal (1991-98) CULT See Figures 28 and 29 It is not necessary to remove the engine or rear main bearing cap when removing the one-piece oil seal on these engines although you may find it easier to do just that. 1. Remove the flywheel housing and cover as detailed in this section. 2. Remove the engine coupler and flywheel from the engine as detailed in this section. 3. Remove the seal retainer. This is not absolutely necessary. Insert a small into one of the three slots in the edge of the seal retainer and slowly pry the seal out of the retainer. Be very careful not to nick or damage the sealing surface while prying out the seal. 5. Thoroughly clean the retainer surface and then install the retainer. 6. Spread a small amount of engine oil around the inside and outside edges of a new seal and position it over its slots in the retainer. 7. Position a seal driver (J-35621) over the seal and crankshaft and then thread the attaching screws into the holes in the crankshaft, tightening them securely. Turn the handle on the tool until it bottoms out-the seal is now in place. 8. lnstall the flywheel and engine coupler. lnstall the cover and flywheel housing. REMOVAL INSTALLATION Engines Only CULT See Figure 28 It is not necessary to remove the engine or rear main bearing cap when removing the one-piece oil seal on these engines although you may find it easier to do just that. A new oil seal must be installed whenever the retainer is removed. 1. Remove the oil pan. 2. Remove the flywheel. Fig. 29 Use a seal driver to seat the new oil seal 3. Loosen the nutslbolts and then lift out the retainer and gasket. 4. Replace the oil seal. 5. Clean all traces of old material from the mating surfaces and position a new seal on the block. 6. lnstall the seal retainer, and a new gasket, and tighten the nutslbolts to 135 inch (15 Nm). 7. lnstall the oil pan and flywheel as previously detailed. REMOVAL INSTALLATION T See Figures 30 and 31 If the engine is in the boat, install an engine hoist and tighten the chain so that the engine's weight is removed from the front engine mount. Remove the front engine mount. 2. Remove the seawater pump from the front of the crankshaft on models so equipped. 3. Remove the drive belts. 4. Loosen the bolts balancer to the hub and remove the assembly-the does not use the balancer. 5. Install special tool #J-6978-E onto the hub with two 3/8-24 x 2 in. bolts and a x 2 in. bolt for the or three 3/8-24 x 2 in. bolts on the Tighten the tool press bolt and remove the hub. OMC suggests that you do not use a conventional gear puller for this procedure. To install: 6. Coat the front cover oil seal lip with clean engine oil and then install the balancerlpulley over the crankshaft and key. You can use a rubber mallet to position it temporarily. 7. lnstall the installation tool #J-5590 onto the hub. Be sure that you thread the tool into the crankshaft at least in. to protect the threads. The crankshaft actually extends slightly through the front of the assembly, so make sure to use the correct tool. In order that the timing mark can be properly positioned, there are two 318 in. holes and one 5116 in. holes in the hub that must be matched. 8. lnstall the drive belts and make sure that it is adjusted properly. 9. lnstall the seawater pump if removed. 10. Install the front mount and unhook the engine hoist. 4-14 ENGINE MECHANICAL -GM 4 CYLINDER ENGINES Fig. 32 Removing the nozzle Fig. 30 Use a special puller to remove the Fig. 31 ...and then install it with another hub... REMOVAL INSTALLATION See Figures and 34 This procedure may require engine removal, depending upon your particular boat. If necessary, remove the engine as detailed previously in this section. 1. Open the drain valves and drain the coolant from the block and exhaust manifold. 2. Loosen the alternator and power steering brackets to provide slack, and then remove the drive belts. 3. Remove the harmonic assembly. 4. Remove the water circulation pump. 5. Secure the engine with a hoist and remove the front engine mount if you haven't already removed the engine. 6. Drain the oil and remove the oil pan. 7. Loosen all of the front cover retaining screws and then pull off the cover and gasket. Clean all gasket material from the cover and block mating surfaces. 8. Pry the oil seal from the timing gear cover with a large drift or 9. Grasp the oil nozzle with a pair of pliers and pull it out of the cylinder block. Fig. 33 Use the special tool to drive the seal into the cover To install: Insert a new oil nozzle into the block and drive it into position with a rubber mallet, 11. Coat both sides of a new oil seal lightly with grease and then position it into the cover so that the lip (open side) faces into the cover. With the cover on a clean flat surface, position a seal installer over the seal and drive it into place with a hammer. Clean all old gasket material from the cover and block mating surfaces. Coat a new gasket lightly with grease and stick it into position on the cylinder block. 13. The seal installer tool also acts as a centering tool. lnstall the tool onto the crankshaft and slide the cover over the tool and into position. Install the mounting screws and tighten them to 6-8 ft. Ibs. (9-10 on 1986-92 engines, or 80 inch Ibs. (9 Nm) on engines. Tighten the screws evenly and gradually. Remove the centering tool. 15. lnstall the water circulation pump and the harmonic balancerlhub. 16. Install the oil pan. 17. Install all belts and check their tension. 18. Reinstall the engine mount; or if you removed the engine, install it now. 19. Refill the engine with oil and coolant. Fig. 34 Exploded view of the front cover ENGINE MECHANICAL -GM 4 CYLINDER ENGINES 4-15 We recommend checking the camshaft lift prior to removing it from the cylinder block. CHECKING ERA See Figure 35 Tag and disconnect the electrical connectors at the ignition coil. 2. Remove the cylinder head cover and rocker arms as detailed previously. 3. Using a special adaptor connect a dial indicator so that its tip is positioned on the end of the pushrod-the adaptor should screw onto the end of the rocker stud. 4. Slowly rotate the crankshaft in the direction of engine rotation until the valve lifter is riding on the heel (back side of lobe) of the camshaft lobe. The should be at its lowest point when the lifter is on the heel. A remote starter works well for turning the engine over in this situation. 5. Set the indicator to and then rotate the engine until the is at the highest point of its travel. Camshaft lift should be 0.253 0.005 in. (6.426 6. Continue rotating the engine until the is back at its lowest position-make sure that the indicator still reads 7. Repeat this procedure for the remaining pushrods. 8. lnstall the rocker arms and adjust the valve clearance. 9. Install the cylinder head cover and reconnect the coil leads, REMOVAL INSTALLATION CULT See Figure 36 thru 41 This procedure may require engine removal, depending upon your particular boat. If necessary, remove the engine as detailed previously in this section. 1. Drain the engine oil 2. Open the drain valves and drain the coolant from the cylinder block and exhaust manifold. 3. Remove the cylinder head cover and gasket. Loosen the rocker arm nuts just enough so that you can rotate the rockers off of the ends. 4. Mark the position of the distributor's No. cylinder terminal on the housing of the distributor and then remove the cap. Matchmark the distributor and the cylinder block, loosen the hold down clamp and lift out the distributor. 5. Remove the ignition coil and side cover gasket, Take time to set up a system to keep the push rods and valve lifters in order, to ensure each will be installed back into the exact location from which it was removed. Withdraw each push rod and valve lifter in order. 6. Remove the harmonic balancer 7. Remove the water circulation pump. 8. Secure the engine with a hoist and remove the front engine mount if you haven't already removed the engine. 9. Remove the oil pan. 10. Remove the front cover and gasket. Clean all gasket material from the cover and block maiing surfaces. 11. Rotate the camshaft gear until the holes in the gear are aligned with the thrust plate screws. Remove the two screws. Carefully withdraw the camshaft gear and camshaft by pulling the gear straight forward and the shaft out of the block. Dial n Fig. 35 Use a dial indicator when checking the camshaft lift Be very careful not to damage the camshaft bearings while removing the camshaft. 12. Check the gear and thrust plate end-play. This clearance should be 0.001-0.005 in. max. If the decision is made to replace the camshaft gear, or the thrust plate, the gear must be pressed from the shaft. Gear removal from the camshaft requires the use of camshaft gear removal tool and an arbor press. Place the end of the removal tool onto the table of an arbor press, and then press the shaft free of the gear. The thrust plate must be positioned to prevent the woodruff key in the shaft from damaging the shaft when the shaft is pressed out of the gear. Also, be sure to support the end of the gear or the gear will be seriously damaged. 13. If the camshaft bearings are to be removed, you will need to remove the flywheel as previously detailed. Although it is not necessary, removing the crankshaft will also facilitate bearing removal, make sure that you move the connecting rods out of the way so they do not interfere with bearing removal. 14. Working from inside the block, drive out the rear cam bearing expansion plug (welch plug). 15. Slide the pilot tool into position in the inner bearing. Install a nut onto the puller screw so that the screw can be threaded into the tool with the nut still extending out the front of the cylinder block. 16. lnstall the remover onto the puller screw, slide the screw through the bore and thread it onto the pilot. 17. Hold the screw shaft with a wrench while turning the puller nut with another until the bearing comes out. 18. Now remove the pilot from the shaft and install it onto the drive handle so that the shoulder is against the handle. The front and rear bearings can now be driven out from the outside of the block. To install: 19. Remove the handle from the pilot tool and install the inner bearing on the tool. 20. the tool and bearing to the rear of the inner bore. Install the screw shaft, with the remover, through the block and onto the pilot-from the front of the cylinder block. 21. Align the oil hole in the bearing with the oil gallery hole and then snug the puller nut up against the adaptor. Using two wrenches again, hold the screw shaft with one while turning the puller with the other until the bearing is in position. The oil hole is on the top of the bearing and will not be visible during installation. To make installation easier, align the two holes and then mark the opposite side of the bearingiblock. 4-16 ENGINE MECHANICAL -GM 4 CYLINDER ENGINES I Fig. 36 Line up the timing gear marks and the access holes should rest over the thrust Feeler Gauge Fig. 37 Checking the camshaft Fig. 39 Make sure the timing marks align on both gears 22. Attach the drive handle to the tool and position the new front bearing onto the tool. Align the oil holes and drive the bearing in from the front (outside) of the cvlinder block. Be sure that the is driven in past the of ihe least 118 in, in order to expose oil hole for timing gear nozzle. 23. Repeat the last step for the rear bearing, but remember there is no oil nozzle hole in this bore so the bearing must be flush with the block. Install a new expansion plug at the rear bearing. 25. To assemble the camshaft parts, first firmly support the camshaft at the back of the front journal in an arbor press. Next, place the gear spacer ring and the thrust plate over the end of the shaft, and install the Woodruff key in the shaft keyway. Install the camshaft gear and press it onto the shaft until it bottoms against the gear spacer ring. Check the end-play again. 26. If you removed the crankshaft, install it now. 27. Coat the camshaft lobes with G.M. Super Engine Oil Supplement and then pour the remainder of the can into the crankcase when you refill the engine with oil later in this procedure. 28. Slowly slide the camshaft and gear into the block, being careful not to damage the lobes or bearings. When the shaft is almost all the way in, rotate the camshaft and crankshafts until the timing marks on the teeth of each gear line up and then slide the camshaft in until the thrust plate meets the cylinder block and the holes in the plate line up with those in the block. Slowly rotate the crankshaft until the access holes in the cam gear are over the thrust plate holes. Install the two retaining screws and tighten them to 90 inch Ibs. (8-10 Nm.) Fig. 40 Checking the run-out Fig. 41 Checking the gear backlash ENGINE MECHANICAL -GM 4 CYLINDER ENGINES 4-17 Fig. 42 Cylinder head tightening sequence 29. Connect a dial indicator to the front of the cylinder block with an adaptor so that the needle on the indicator is in contact with the face of the camshaft gear. Rotate the engine 360" checking the run-out as you go. Repeat this procedure for the crankshaft gear. Camshaft should not exceed 0.004 in. Crankshaft run-out should not exceed 0.003 in. If run-out exceeds specification, remove the gear and check for burrs, otherwise replace the gear. 30. Move the dial indicator so that the needle is now riding on a gear tooth. Wiggle the shaft back and forth while checking the backlash reading on the indicator. Backlash should be 0.004-0.006 in. 31. lnstall the oil pan. lnstall the front cover. 31. lnstall the harmonic balancer and water pump. 32. Installation of the remaining components is in the reverse order of removal. Don't forget to add the remainder of the Super Oil Supplement when refilling the engine with oil. REMOVAL INSTALLATION See Figures 42 and 43 TE Drain the water from the cylinder block and manifold. 2. Remove the fuel line support brackets. Disconnect the fuel line at the carburetor and fuel pump, plug the fitting holes and remove the line. 3. Remove the combination manifold as previously detailed in this section; you can leave the carburetor attached if you like. 4. Disconnect the coolant hoses at the thermostat housing and move them out of the way. Have some rags available, as there will still be some coolantlwater in the hoses. 5. Tag and disconnect the temperature sending unit lead at the thermostat housing, loosen the mounting bolts and then remove the housing and thermostat. 6. Tag and disconnect all wires at the ignition coil and then remove the mounting bracket bolt and lift off the coil. 7. Tag and disconnect the spark plug wires at the plugs; move them out of the way. Although not necessary, it's a good idea to remove the plugs themselves also. 8. Remove the circuit breaker bracket and then unbolt and remove the engine lifting bracket (if equipped). 9. Remove the cylinder head cover and rocker assemblies as detailed previously in this section. Remove the pushrods. 10. Loosen the cylinder head bolts, from the center bolts and working out to the ends of the head and then carefully lift the head off the block. You may need to persuade it with a rubber mallet-be careful! Set the head down carefully do not sit it on cement. To install: 11. Carefully, and thoroughly, remove all residual head gasket material from the cylinder head and block mating surfaces with a scraper or putty knife. Check that the mating surfaces are free of any nicks or cracks. Make sure there is no dirt or old gasket material in any of the bolt holes. Refer to the Engine Rebuilding section for complete details on inspection and refurbishing procedures. 12. Position a new gasket over the cylinder block dowel pins. On models using a steel gasket, coat both sides of the gasket with a thin layer of Gasket Sealing Compound. Do not use too much sealing compound!! 13. Position the cylinder head over the dowels in the block. Coat the threads of the head bolts with and install them finger tight. It never hurts to use new bolts, although it's not necessary, Tighten the bolts, a little at a time, in the sequence illustrated, until the proper tightening torque is achieved. 1986-93 engines have a final torque of 90-100 ft. Ibs. (122-136 Nm), while 1994-98 engines have a final torque of 95 ft. (129 make sure that you check the Torque Specifications chart for any preliminary 14. lnstall pushrods, rocker assemblies and the cylinder head cover. lnstall the circuit breaker and engine lifting brackets, lnstall the spark plugs if they were removed and then connect the plug wires. 16. lnstall the coil and reconnect all the electrical leads. 17. lnstall the thermostat housing, the coolant hoses and the temperature sending lead. lnstall the manifold and connect the fuel line. Don't forget to remove the fitting plugs. 19. Add coolantlwater, connect the battery and check the oil. Start the engine and run it for a while to ensure that everything is operating properly. Keep an eye on the temperature gauge. 20. Re-tighten the cylinder head bolts after 20 hours of operation. Fig. 43 Remove the cylinder head carefully 4-18 ENGINE MECHANICAL -GM 4 CYLINDER ENGINES See Figures and 46 cover Ring set Piston cover seal Locknut cover Fig. 44 Exploded view of the cylinder block-3.01 engines, similar ENGINE MECHANICAL -GM 4 CYLINDER ENGINES 4-19 Clamp Elbow PCV hose Cylinder head cover Valve Stem I Exhaust Valve Rocker arm - Head gasket ig. 45 Exploded view of the cylinder head-3.01 engines, similar 4-20 ENGINE MECHANICAL -GM 4 CYLINDER ENGINES Lock washer Screw screw Mount Washer Bolt Fia. 46 view of the and rear mounts-3.01 engines, similar Washer Bolt TORQUE SPECIFICATIONS Component ft. inch Ibs. Nm Alternator bracket to engine 26-30 35-41 Camshaft sprocket Sprocket Thrust plate 72-90 8-10 Combination manifold 20-25 27-34 Connecting rod cap 35 47 Crankshaft Main bearing cap (exc. rear) 60-70 81-95 Main bearing cap (rear) Step 1 10-12 -14-16 Step 60-70 82-94 Oil seal retainer 1991-98 135 15.3 Cylinder head 1986-93 90-100 1994-98 1 A7 Step 2 65 88 Step3 95 129 Cylinder head cover 1986-93 45 5 1994-98 65 7.3 Distributor clamp bolt 20 27 Engine coupler Flywheel housing 28-36 38-49 Coupler nut 40-45 54-61 Coupler ground stud 1986-93 20-25 27-34 1994-98 35-40 -47-54 -Cover 60-84 7-9 Engine mounts Front Bracket bolts 30-35 41-47 - Upper nut 50-60 68-81 Lower nut 115-140 156-190 Mounting bolts Port 48-56 65-76 Starboard 32-40 43-54 Rear Center bolt 1986-88 18-20 -24-27 1989-98 44-52 -60-71 Lock nut 28-30 38-40 Mounting bolts 20-25 27-34 Exhaust Elbow 12-14 16-19 Exhaust Pipe 10-12 -14-16 1990-98 27-34' 27-34 Front cover 6-8 9-10 80 9 Main bearing cap Exc, rear 60-70 81-95 Rear Step1 10-12 14-16 Step2 60-70 81-95 Oil pan x 20 bolts 80 9 5/16 x 18 bolts 165 Drain retainer 15-18 20-24 Sprocket is press-fit to TORQUE SPECIFICATIONS Component ft. inch Ibs. Nm Oil pump Cover bolts -65-75 7-8 Mounting bolts -110-120 12-14 Oil withdrawal tube (flare) 15-18 -20-24 Power steering pump Bracket Pick-up Tube 60 7 Oil pressure sender adapter 10-14 14-19 Oil seal retainer 1991-98 135 15.3 26-30 35-41 Stud 13-15 18-20 Hydraulic fitting Large 15-17 20-23 Small 10-12 14-16 Raw water pump bracket 13-17 -18-23 Timina chain cover 6-8 Valve cover 1994-98 65 7.3 Water pump (circulating pump) 13-17 -18-23 Water temperature sender 20 27 Sprocket is press-fit to camshaft ENGINE SPECIFICATIONS ENGINE SPECIFICATIONS Standard Metric Standard Metric Component (in.) (mm) Component (in.) (mm) Camshaft Piston Rings Bearing Length 0.86 21.84 Compression Bearing Outer Diameter 1.999-2.001 50.78-50.83 0.010-0.020 0.25-0.51 1.8687 2.009-2.011 51.03-51.08 3 1.8692 Journal Diameter 47.48 Upper 020 0.25-0.51 47.47 Lower 0.33-0.64 Lobe Lift 0.253 +/-0.005 6.43 +/-0.13 Width 0.0775-0.0780 1.97-1.98 Rod Oil 0.00085-0.00135 0.022-0.034 Bearing Clearance 0.0007-0.0027 0.018-0.069 Gap 0.015-0.055 0.38-1.40 Width 0.797-0.802 20.24-20.37 0.792-0.822 20.12-20.88 Ring 0.150-0.156 0.154-0.160 End Play 0.008-0.015 0.20-0.38 Groove 0.188-0.189 4.78-4.80 Length 3.81-3.96 Crankshaft 1.999-2.000 50.78-50.80 Valve system 2.099-2.100 53.32-53.34 Face Angle 45 deg. Crankshaft End Play 0.002-0.006 0.05-0.15 Main Bearing Clearance 0.0003-0.0029 0.008-0.074 Journal Diameter 2.2983-2.2993 58.38-58.40 Length thru 4 0.83 21.08 0.822 20.88 , , Piston Free length 2.08 52.83 Clearance Pressure 78-86 N Limit at top land 0.0245-0.0335 1.66 42.16 0.0005-0 0015 0.013-0.038 0.0025-0.0035 0.064-0.089 0.200-0.208 0.209-0.21 1 202 4.93-5.13 0.190-0.199 0.0255-0.0345 Stem Clearance Limit at skirt Groove Compression ring Unless otherwise noted Oil ring 0.802 (20.37) 314to 1 full turn down from zero lash Piston Pin Clearance Production Service Limit 0.001 Max 0.02 Max Diameter 0.9270-0.9273 23.55-23.56 fit 0.0008-0.0021 0.020-0.050 Length 2.990-3.010 75.95-76 45 Unless otherwise noted 0.802 (20.37) 314 to 1 full down from zero lash BALANCE SHAFT 5-31 REMOVAL INSTALLATION 5-31 CAMSHAFT ........................ 5-31 CHECKING 5-31 REMOVAL INSTALLATION 5-32 CYLINDER HEAD 5-33 REMOVAL INSTALLATION 5-33 CYLINDER HEAD (VALVE) COVER 5-8 REMOVAL INSTALLATION 5-8 ENGINE 5-4 MINIMUM ENGINE HEIGHT 5-6 ENGINE ALIGNMENT 5-6 MODEL DESIGNATIONS 5-4 REMOVAL INSTALLATION 5-4 ENGINE CIRCULATING (WATER) PUMP . . 5-34 REMOVAL INSTALLATION 5-34 ENGINE AND FLYWHEEL 5-25 REMOVAL INSTALLATION 5-25 ENGINE IDENTIFICATION 5-2 ENGINE MECHANICAL BALANCE SHAFT 5-31 CAMSHAFT 5-31 CYLINDER HEAD 5-33 CYLINDER HEAD (VALVE) COVER 5-8 ENGINE 5-4 ENGINE CIRCULATING (WATER) PUMP . 5-34 ENGINE AND FLYWHEEL 5-25 ENGINE IDENTIFICATION 5-2 EXHAUST HOSES (BELLOWS) 5-20 EXHAUST MANIFOLD 5-17 FRONT COVER AND SEAL 5-29 FRONT ENGINE MOUNTS 5-7 GENERAL INFORMATION 5-2 HARMONIC BALANCER, PULLEY AND HUB 5-28 EXHAUST ELBOW 5-20 HYDRAULIC VALVE LIFTER 5-10 INTAKE MANIFOLD 5-12 INTERMEDIATE EXHAUST 5-20 LOWER EXHAUST PIPE (Y-PIPE) 5-20 FILTER BYPASS VALVE 5-24 PAN 5-21 PUMP 5-23 REAR ENGINE MOUNTS 5-7 REAR SEAL 5-27 REAR OIL SEAL RETAINER 5-27 ROCKER ARMS AND PUSH RODS 5-8 TIMING CHAIN AND SPROCKETS 5-30 WATER PUMP 5-34 EXHAUST HOSES (BELLOWS) ......... 5-20 REMOVAL INSTALLATION .......... 5-20 EXHAUST MANIFOLD 5-17 REMOVAL INSTALLATION 5-17 EXHAUST VALVE (FLAPPER) ........... 5-21 REPLACEMENT .................... 5-21 EXPLODED VIEWS 5-35 FRONT COVER AND SEAL ......... 5-29 REMOVAL INSTALLATION 5-29 FRONT ENGINE MOUNTS 5-7 REMOVAL INSTALLATION 5-7 GENERAL INFORMATION ............. 5-2 V6 ENGINES ...................... 5-2 ENGINES ...................... 5-2 HARMONIC BALANCER . PULLEY INSTALLATION .......... 5-28 EXHAUST ELBOW 5-20 REMOVAL INSTALLATION 5-20 HYDRAULIC VALVE LIFTER 5-10 REMOVAL INSTALLATION 5-10 INTAKE MANIFOLD 5-12 REMOVAL INSTALLATION .......... 5-12 INTERMEDIATE EXHAUST ........ 5-20 REMOVAL INSTALLATION .......... 5-20 LOWER EXHAUST PIPE (Y-PIPE) 5-20 REMOVAL INSTALLATION .......... 5-20 OIL FILTER BYPASS VALVE ............ 5-24 REMOVAL INSTALLATION .......... 5-25 PAN ........................... 5-21 REMOVAL INSTALLATION .......... 5-21 .......................... 5-23 REMOVAL INSTALLATION .......... 5-23 REAR ENGINE MOUNTS 5-7 REMOVAL INSTALLATION .......... 5-7 REAR SEAL ................ 5-27 REMOVAL INSTALLATION .......... 5-27 REAR OIL SEAL RETAINER ....... 5-27 REMOVAL INSTALLATION .......... 5-27 ROCKER ARMS AND PUSH RODS ...... 5-8 REMOVAL INSTALLATION .......... 5-8 VALVE ADJUSTMENT ................ SPECIFICATIONS 5-39 ENGINE 5-43 TORQUE 5-39 TIMING CHAIN AND SPROCKETS 5-30 REMOVAL INSTALLATION .......... 5-30 VALVE ADJUSTMENT 5-9 WATER PUMP 5-34 REMOVAL INSTALLATION 5-34 ......................... 5-28 REMOVAL 5-2 ENGINE MECHANICAL-GM V6 AND V8 ENGINES NEVER, NEVER attempt to use standard automotive parts when replacing anything on your engine. Due to the uniqueness of the environment in which they are operated in, and the levels at which they are operated at, marine engines require different versions of the same part; even if they look the same. Stock and most aftermarket automotive parts will not hold up for prolonged periods of time under such conditions. Automotive parts may appear identical to marine parts, but be assured, OMC marine parts are specially manufactured to meet OMC marine specifications. Most marine items are super heavy-duty units or are made from special metal alloy to combat against a corrosive saltwater atmosphere. OMC marine electrical and ignition parts are extremely critical. In the United States, all electrical and ignition parts manufactured for marine application must conform to stringent Coast Guard requirements for spark or flame suppression. A spark from a non-marine cranking motor solenoid could ignite an explosive atmosphere of gasoline vapors in an enclosed engine compartment. ENGINES The OMC 262 cubic inch displacement V6 engine is manufactured by GMC. This engine is used in numerous models known as the 4.3, 4.3 and The 4.3 and models are equipped with a 2-barrel carburetor, while the HO and models are equipped with a 4-barrel carburetor. Throttle body fuel injection was introduced on the in 1996. The lubrication systems and component locations on this engine are virtually identical to the larger V8 engines, except for having only three cylinders in each bank. A balance shaft is mounted above the camshaft on all 1994 and later models and extends the entire length of the block and is supported on each end by a bearing. The balance shaft is driven by gears on the end of the camshaft and equalizes the dynamic forces known as harmonic vibrations minimizing engine vibration during routine operation of a V6 engine. Cylinder numbering and firing order is identified in the illustrations at the end of the Maintenance Section. All engines are left hand (counterclockwise) rotation when viewed from the stern of the boat. This does not necessarily indicate that your prop rotation is the same-always check them both! V8 ENGINES The OMC 305 cubic inch and 350 cubic inch displacement (small block) V8 engines are manufactured by GMC. These engines are used in the following configurations: 5.0 (214 bbl) 5.7 (4 bbl) ' (TBI) bbl) (TBI) 5.7 LE (4 bbl) 350 (4 bbl) The OMC 454 cubic inch and 502 cubic inch displacement (big block) V8 engines are also manufactured by GMC. These engines are used in the following configurations: 7.4 (4 bbl) 7.4 454 (4 bbl) 7.4 EFI (MPI) (4 bbl) (MPI) (MPI) (4 bbl) (MPI) 454 (4 bbl) 454 HO (4 bbl) 502 (4 bbl) The lubrication system is a force fed type where oil is supplied under full pressure to the crankshaft, main and connecting rod bearings, camshaft bearings and the valve lifters. Oil flow from the valve lifters is metered and pumped by the lifter through the hollow core to lubricate the rocker arms and valve train. All other components are lubricated by gravity and splash methods. The oil pump is mounted on the rear main bearing cap and is driven by an extension shaft from the distributor-driven by the camshaft. Oil is drawn into the pump through the oil pick-up tube and screen. Should the screen become clogged, a relief valve in the screen will open and allow oil to be drawn into the pump. Once oil reaches the pump, the pump forces oil through the lubrication system. A spring-loaded relief valve in the oil pump limits the maximum pump output pressure. The pressurized oil flows out the pump through a full-flow disposable oil filter cartridge. On engines equipped with an oil cooler, the oil flows through the filter, out to the oil cooler via hoses and then returns to the block. Should the oil filter cooler become clogged, a by-pass valve will open allowing the pressurized oil to by-pass the filter and cooler. Some of the oil is then routed to the No. 5 crankshaft main bearing, the remainder of the oil pressure is routed to the main oil gallery. The main oil gallery is located above the camshaft and runs the full length of the block. Oil from the main gallery is routed through individual passages to the camshaft bearings, No's 2, 3, and 4, crankshaft main bearings and the lifter galley's on each side of the block. Holes in the camshaft bearings and crankshaft main bearings align with the holes in the block for oil flow. Grooves in the bearings allow oil to flow between the bearing and the component. Oil in the lifter galleries is forced into each hydraulic lifter through a hole in the side of the lifter. Oil flowing through the lifter must pass through a metering valve in each of the lifters. The metered volume of oil then flows up through the hollow push-rods to the valve rockers. A small hole in the rocker arm allows oil to lubricate the valve train bearing surfaces. All excess oil drains back to the oil pan through oil return holes in the cylinder head. A baffle plate or "splash pan" mounted below the main bearing caps prevents excess oil being thrown off the crankshaft from aerating the oil in the oil pan. The distributor shaft and gear is lubricated by oil in the starboard lifter gallery. The timing chain and gears are lubricated with oil flowing out the front of the No. main bearing journal. The mechanical fuel pump and is lubricated with oil thrown off the camshaft eccentric. All V8 engines are left hand (counterclockwise) rotation when viewed from the stern of the boat except some which are right hand (clockwise). This does not necessarily indicate that your prop rotation is the always check them both! Cylinder numbering and firing order is identified in the illustrations at the end of the Maintenance Section. ENGINE See Figures and 4 The engine serial numbers are the manufacturer's key to engine changes. These alpha-numeric codes identify the year of manufacture, the horsepower rating and various differences. If any correspondence or parts are required, the engine serial number must be used for proper identification. Remember that the serial number establishes the year in which the engine was produced, which is often not the year of first installation. The engine specifications decal contains information such as the model number or code, the serial number (a unique sequential identifier given ONLY to that one engine) as well as other useful information. An engine specifications decal can generally be found on top of the flame arrestor, on the side of the thermostat housing (early engines), or on the inner side of the rocker arm cover, usually near the line (port side on most models) all pertinent serial number information can be found here-engine and drive designations, serial numbers and model numbers. Unfortunately this decal is not always legible on older boats and it's also quite difficult to find, so please refer to the following procedures for each individuals unit's serial number location. ENGINE MECHANICAL-GM V6 AND V8 ENGINES Model Year Designation: Randomly chosen PRA Decoding the engine Randomly chosen for each major non-interchangeable model number is easy Propeller Rotation: E = Either R = Right Hand L = Left Hand Model Year Version: King Cubic Inches engines Fig. 3 Engine serial number sticker-V6 and V8 engines Fig. 4 You should also be able to find a plate on the transom bracket Serial numbers tags are frequently difficult to see when the engine is installed in the boat; a mirror can be a handy way to read all the numbers. The engine number is sometimes also stamped on the port rear side of the engine where it attaches to the bell housing; although on most later models it may instead be a metal plate attached in the same location. If your engine has a stamped number it will simply be the serial number; if you have a plate (and you should), it will always show a Model number and then the actual Serial number. Additionally, most models will also have this plate or sticker on the transom bracket. The first two characters identify the engine size in liters (L); 43 represents the 50 represents the and so forth. The third character identifies the fuel delivery system; 2 designates a 2 bbl carburetor, 4 is a 4 bbl carburetor, and F is a fuel injected engine. The fourth character designates a major engine or horsepower change-it doesn't let you know what the change was, just that there was some sort of change. A means it is the first model released, B would be the second, and so forth. The fifth character designates what type of steering system was used; M would be manual steering and P be power steering. Now here's where it gets interesting; on engines and 1994-98 engines, the sixth, seventh and eighth characters designate the model year. The sixth and seventh actually show the model year, while the eighth is a random model year version code. KWB and WXS represent 1986; and ARJ, ARF, FTC, SRC or SRY show 1987. MDA is 1994, HUB is 1995, NCA is 1996, LKD is 1997 and BYC is 1998. On engines, the sixth character designates the direction of propeller rotation. is right hand, L is left hand and E is either. Also on engines, the seventh, eighth and ninth characters designate the model year. The seventh and eighth actually show the model year, while the nineth is a random model year version code. GDE or GDP is 1988, MED or MEF is 1989, PWC, PWR or PWS is 1990, RGD or RGF is 1991, AMH or AMK is 1992 and JVB or JVN is 1993. Any remaining characters are proprietary. So in example, a Model number on the ID plate that reads would designate a 1987 engine with a 4 bbl carburetor and manual steering, first model released. A number readina desianate a 1993 enaine with fuel iniection, and a right first get the 5-4 ENGINE MECHANICAL-GM V6 AND V8 ENGINES Engine Model Designations Most engines covered here utilize unique identifiers assigned by OMC; surnames if you etc. Obviously the first two characters designate the engine size in litres (L). The second letter, a G or and F designate the engine manufacturer; General Motors (G) or Ford (F). The third through fifth letters can be found in different combinations, but the individual letter designates the same thing regardless of position. L designates limited output. S and X designate superior output-a will always have a lesser horsepower rating than a in a given model year; a will be less than a An i designates that the engine is fuel injected, if there is no i then you know the engine uses a carburetor. Fig. 5 Disconnect the power steering lines at the cylinder REMOVAL INSTALLATION CULT See Figures 5 thru 12 Prior to removing the engine from your vessel on all 1994-98 models, it is imperative to measure the engine height as detailed in the Determining Minimum Engine Height section. DO NOT remove the engine until you have completed this procedure! 1. Check the clearance between the front of the engine and the inside edge of the engine compartment bulkhead. If clearance is less than 6 in. you will need to remove the stern drive unit because there won't be enough room to disengage the driveshaft from the engine coupler. More than 6 in, will provide enough working room to get the engine out without removina the drive. BUT, we recommend removina the drive anvwav. If vou intend doing anything to the mounts or you will need re-align the engine as detailed in the Engine Alignment section-which requires removing the drive, so remove the drive! 2. Remove the stern drive unit as detailed in the Drive Systems section. 3. Open or remove the engine hatch cover. 4. Disconnect the battery cables (negative first) at the battery and then disconnect them from the engine block and starter. 12. Drain the cooling system as detailed earlier in this section. 13. Loosen the hose clamp on the water supply hose at the transom bracket and carefully slide it off the water tube. Attach the hose to the engine. On big block engines, disconnect the water line at the oil cooler on the rear of the block. 14. Disconnect the shift cables and position them out of the way. 15. Tag and disconnect any remaining lines, wires or hoses at the engine. 16. Attach a suitable engine hoist to the lifting eyes and take up any line slack until it is just taught. The engine hoist should have a capacity of at least 1500 (680 17. Locate the rear engine mounts and remove both lock nuts and flat washers. 18. Locate the front engine mounts and remove the two (per mount) lag bolts. 19. If you listened to us at the beginning of the procedure, the drive unit should be removed. If so, and lift out the enaine. not to hit the power steering control valve, or any accessories, while. removing it from the engine compartment. If you didn't listen to us, and you had clearancein the engine compartment, the drive unit is probably still installed. Raise the hoist slightly until the weight is removed from the mounts and then carefully pull the engine forward until the driveshaft disengages from the coupler, now raise the engine out of the compartment. Fig. 6 Disconnect the fuel inlet line Make sure that all switches and systems are OFF before disconnecting the batterv cables. 5. Disconnect the two power steering hydraulic lines at the steering cylinder (models Carefully plug them and then tie them off somewhere on the engine, making sure that they are higher then the pump to minimize any leakage. 6. Disconnect the fuel inlet line at the fuel pump or filter (whichever comes first on your particular engine) and quickly plug it and the inlet-a clean tee and some tape works well in this situation. Make sure you have handy, as there will be some spillage. 7. Tag and disconnect the two-wire connector. 8. Pop the two-wire trimltilt sender connector out of the retainer and then disconnect it. You may have to cut the plastic tie securing the cable in order to move it out of the way. 9. Locate the large rubber coated instrument cable connector (should be on the starboard side), loosen the hose clamp and then disconnect it from the bracket. Move it away from the engine and secure it. On early models, you will also need to unplug the three-wire trimltilt cable connector just above it. Take note of you throttle arm attachment stud-is it a close" or a "pull-to-close"? What hole is it on?? 10. Remove the cotter pin and washer from the throttle arm. Loosen the anchor block retaining nut and then spin the retainer away from the cable trunnion. Remove the throttle cable from the arm and anchor bracket. Be sure to mark the position of the holes that the anchor block was attached to. 11. Loosen the 4 hose clamps and disconnect the intermediate exhaust hose bellows from intermediate pipe. You may want to spray some WD-40 around the lip of the hose where it connects to the elbow, grasp it with both hands and wiggle it back and forth while pulling down on it. Slide it down over the lower pipe. ENGINE MECHANICAL-GM V6 AND V8 ENGINES 5-5 Cotter Din Anchor bracket I I Fig. 7 Details of the throttle cable assembly-1994-98 engines except fuel injected engines To install: 20. Apply Engine Coupler grease to the splines of the coupler. 21. Slowly lower the engine into the compartment. If the drive unit was not removed, AND the crankshaft has not been rotated, insert the driveshaft into the coupler as you push the engine backwards until they engage completely and then lower the engine into position over the rear mounts until the front mounts just touch the stringers. If the shaft and coupler will not align completely, turn the crankshaft or driveshaft slightly until they mate correctly. If the drive was removed, or the mounts were disturbed in any way, lower the engine into position over the rear mounts until the front mount just touches the stringer. 22. Install the two flat washers into the recess in the engine bracket side of the rear mounts and then install the two lock nuts. Tighten them to 28-30 ft. (38-40 Nm). Never use an impact wrench or power driver to tighten the locknuts. 23. Install the lag bolts into their holes on the front mounts and tighten each bolt securely. If the drive was removed, the mounts were disturbed or the didn't mate correctly, perform the engine alignment procedure detailed in this section. We think it's a good idea to do this regardless! 25. Reconnect the exhaust bellows by sliding it up and over the pipe, position the clamps between the ribs in the hose and then tighten the clamps securely. Make sure you don't position the clamps into the expanding area. 26. Reconnect the water inlet hose. Lubricate the inside of the hose and wiggle it onto the inlet tube. Slide the clamp over the ridge and tighten it securely. This sounds like an easy step, but it is very important-if the hose, particularly the underside, is not installed correctly the hose itself may collapse or come off. Either scenario will cause severe damage to your engine, so make sure you do this correctly! Anchor block Throttle arm retaining screw cable Throttle Throttle I ing Fia. 8 Details of the throttle cable assembly-1994-98 and 27. Carefully, and quickly, remove the tape and plugs so you can connect the power steering lines. Tighten the large fitting to 15-17 ft. (20-23 Nm) and the small fitting to 10-12 ft. Ibs. (14-16 Nm). Don't forget to check the fluid level and bleed the system when you are finished with the installation. 28. Reconnect the connector so the two halves lock together. 29. Reconnect the trim position sender leads, the instrument cable, the engine ground wire, the battery cables and all other wires, lines of hoses that were disconnected during removal. Make sure you swab a light coat of grease around the fitting for the large enginelinstrument cable plug. Fig. 10 then connect and engine hoist Boss \ Groove Fig. 11 Details of the throttle cable and trunnion1994- 98 engines Fig. 12 Attach the anchor block assembly to the bracket1994- 98 enaines ENGINE MECHANICAL-GM V6 AND V8 ENGINES Always make certain that all switches and systems are turned OFF before reconnecting the battery cables. Make sure all cables, wires and hoses are routed correctly before initially starting the engine. 30. Unplug the fuel line and fitting and reconnect them. Remember to check for leaks as soon as you start the engine. 31. lnstall and adjust the throttle cable. For complete details, please refer to the Fuel System section): a. Remember we asked you to determine if you had a "push-to-close" or "pull-to-open" throttle cable (the throttle arm stud)? Position the remote control handle in Neutral-the propeller should rotate freely. b. Turn the propeller shaft and the shifter into the forward gear detent position and then move the shifter back toward the Neutral position halfway. c. Position the trunnion over the groove in the throttle cable so the internal bosses align and then snap it into the groove until it is fully seated. d. lnstall the into the anchor block so the open side of the trunnion is against the block. Position the assembly onto the bracket over the original holes (they should be the lower two of the four holes) and then install the retaining bolt and nut. When the nut is securely against the back of the bracket, tighten the bolt securely. e. lnstall the connector onto the throttle cable and then pull the connector until all end play is removed from the cable. Turn it sideways until the hole is in alignment with the correct stud on the throttle arm. Slide it over the stud and install the washer and a new cotter pin. Make sure the cable is on the same stud that it was removed from. Tighten the jam nut against the connector The throttle arm connector nut must be installed on the cable with a minimum of 9 turns-meaning that at least 114 in. of thread should be showing between the end of the cable and the edge of the nut. 32. lnstall and adjust the shift cables. Please refer to the Drive Systems section for further details. 33. Check and refill all fluids. Start the engine and check for any fuel or coolant leaks. Go have fun! MINIMUM ENGINE HEIGHT Engines Only 4 See Figure 13 This procedure MUST be performed prior to removing the engine from the vessel. 1. With the engine open, position a long level across the transom running fore and aft. 2. Have a friend or assistant steady the level while you measure from the bottom edge of the tool to the top of the exhaust elbow. Record the distance as "1". 3. Now measure from the bottom of the level to the static water line on the drive unit. Record the distance as Fia. 13 Use a level to determine minimum enaine heiaht Fig. 15 A good view of the front engine mount and its components 4. Subtract the elbow measurement (1) static waterline measurement (2). the result is less than 13 in. on V6 engines or 14 in. on V8 engines, an exhaust elbow high rise kit must be installed (available from your local parts supplier). ENGINE ALIGNMENT CULT 4 See Figures 14 and Engine alignment is imperative for correct engine installation and also for continued engine and drive operation. It is a good idea to ensure proper alignment every time that the drive or engine has been removed. Engine alignment is checked by using OMC alignment tool and handle Engine alignment is adjusted by raising or lowering the front engine With the drive unit off the vessel, slide the alignment tool through the gimbal bearing and into the engine coupler. It should slide easily, with no binding or force. If not, check the gimbal bearing alignment as detailed in the Drive Systems section. If bearing alignment is correct, move to the next step. 2. If vour enoine utilizes a iam nut on the bottom of the mount bolt. loosen it it off at in. 3. Loosen the lock nut and back it off. 4. Now, determine the engine requires raising or lowering to facilitate alignment-remember, the alignment tool should still be in position. Tighten or loosen the adjusting nut until the new engine height allows the alignment tool to slide freely. 5. Hold the adjusting nut with a wrench and then tighten the lock nut to 100-120 ft. Ibs. Nm). If your engine uses a jam nut, cinch it up against the lock nut. 6. Remove the alignment tool and handle. Fig. 14 lnstall the alignment tool through the gimbal bearing ENGINE MECHANICAL-GM V6 AND V8 REMOVAL INSTALLATION See Figures 15 and 16 1. Position an engine hoist over the engine and hook it the two engine lifting eyes. 2. Remove the two lag on each side of the mount where it rests on the stringer. 3. Raise the engine just enough to allow working room for removing the mount. 4. Remove the three mount-to-engine mounting bolts with their lock washers and lift out the mount. One of the bolts is hidden under the bracket, behind the mount bolt. Some engines may use bolts of different lengths; mark them so you can replace them in their original locations. 5. Measure the distance between the top of the large washer on the mount and the flat on the lower side of the mounting bracket. Record it. 6. Position a wrench over the bottom nut on the adjusting bolt, just underneath the mount, to hold the shaft and then remove the too nut. Lift off the bracket. 7. Remove the two lock nuts from the bolt and slide out the adjusting bolt. Remember which washer goes where. To install: 8. Slide the adjusting bolt up through the mount and then position the small and large washers over the bolt-large over small. 9. Spin on the first (lower) lock nut and tighten it to 60-75 ft. Ibs. 102 10. Screw on the upper lock nut and then position the mount bracket over the bolt. Install the washer and adjusting nut and check the measurement taken in Step 5. Move the upper lock nut up or down until the correct specification is achieved and then tighten the adjusting nut to 120 ft. (136-163 Nm) on V6 and engines; 50-70 ft. Ibs. (68-95 Nm) on and engines. 11. Spray the three mounting bolts with Primer N and allow them to air dry. Once dry, coat the bolts with Loctite or OMC Thread Sealing Agent and attach the mount to the engine. Tighten the bolts to 32-40 ft. Ibs. (43-54 Nm). 12. Position the mount over the lag screw holes and then slowly lower the engine until all weight is off the hoist. Install and tighten the lag screws securely. 13. If you're confident that your measurements and subsequent adjustment place the engine exactly where it was prior to removal, then you are through. If you're like us though, you may want to check the engine alignment before you fire up the engine. REMOVAL INSTALLATION CULT See Figure 17 Remove the engine as detailed previously. 2. Loosen the two bolts and remove the mount from the transom plate. Remember, you will already have removed the top lock nut and the washer during engine removal. 3. Hold the square nut with a wrench and remove the shaft bolt. Be sure to take note of the style and positioning of the two mount washers as you are removing the bolt. Mark them, lay them out, or write it down, but don't forget their orientation!! To install: 4. Slide the lower of the two washers onto the mount bolt, exactly as it came off. 5. Slide the bolt into the flat (bottom) side of the rubber mount, install the remaining washer (as it came off!) and then spin on the square nut. Do not tighten it yet. washer installation will cause excessive vibration during engine operation. 6. Turn the assembly upside down and clamp the square nut in a vise. Spin the assembly until the holes in the mounting plate are directly opposite any two of the flat sides on the nut. This is important, otherwise the slot on the engine pad will not engage the mount correctly. Secure the mount in this position and tighten the bolt to 18-20 ft. Ibs. (24-27 Nm) on 1986-88 engines, or 44-52 ft. Ibs. (60-71 Nm) on engines. 7. Remove the mount from the vise and position it on the transom plate. Install the bolts and washers and tighten each to 20-25 ft. Ibs. (27-34 Nm). 8. lnstall the engine, making sure that the slot in the engine pad engages the square nut correctly. lnstall the two washers and locknut and tighten it to 28-30 ft. Ibs. (38-41 Nm). . Fig. 17 A good look at the rear mount bdt in this shot 5-8 ENGINE MECHANICAL-GM V6 AND V8 ENGINES REMOVAL INSTALLATION Fig. 18 Remove the bolts shown)... See Figures and 20 In order to perform this procedure efficiently, we recommend removing the exhaust manifold in order to have sufficient working room to remove the cylinder head cover. Although not completely necessary, it's worth the extra effort to avoid the aggravation of working around the manifolds. Please refer to the manifold procedure later in this section. Open or remove the engine compartment hatch. Disconnect the negative battery cable. 2. Loosen the clamp and remove the crankcase ventilation hose at the cover. Carefully move it out of the way. 3. Tag and disconnect any lines, leads or hoses that might be in the way of removal. In some instances you may be able to simply secure them out of the way without disconnecting them-you be the judge. 4. If your engine has a spark plug wire retainer attached to the cover, the wires or remove the retainer and then tag and disconnect the plug wires at the spark plugs. 5. Loosen the cover mounting bolts (usually three on the V6, four on the and seven or eight on the and lift off the cylinder head cover. Take note of any harness or hose retainers and clips that might be attached to certain of the mounting bolts; you need to make sure they go back in the same place. To install: 6. Clean the cylinder head and cover mounting surfaces of any residual gasket material with a scraper or putty knife. 7. Position a new gasket on the cylinder head and then position the cover (don't forget the J-clips!). Tighten the mounting bolts to: inch Ibs. (11.3 Nm) on 1986-93 engines 62-11 5 inch Ibs. 3 Nm) on engines 106 inch (12 Nm) on 1997-98 engines 45 inch Ibs. (5 Nm) on 1986-96 engines 65 inch (7.3 Nm) on 1991 350 engines 65 inch Ibs. (7.3 Nm) on 1992 5.7 LE engines 90 inch on 1997 enaines the 1997 Fig. 19 ...and then lift off the cover Fig. 20 Position a new gasket on the head 106 inch Ibs. (12 Nm) on 1997 and 1998 V8 engines 11 5 inch Ibs. (1 3 Nm) on engines, except and 60-90 inch (7-10 Nm) on 1996-97 engines 72 inch Ibs. (8 Nm) on 1998 engines Make sure any retainers or clips that were removed are back in their original positions. 8. Connect the crankcase ventilation hose and any other lines or hoses that may have been disconnected. Check that there were no other wires or hoses you may have repositioned in order to gain access to the cover. Install the exhaust manifold. 10. Connect the battery cables. REMOVAL INSTALLATION 1992-98 V6 and 1992-98 V8 Engines See Figure 21 TE Open or remove the engine hatch cover and disconnect the negative battery cable. Remove the cylinder head cover as detailed previously. 2. Bring the piston in the No. cylinder to TDC. If servicing only one arm, bring the piston in that cylinder to TDC. The No. Icylinder is the first cylinder at the port side of the engine. 3. Loosen and remove the rocker arm nut on the V6, shoulder bolt on the V8. Lift out the ball. 4. Lift the arm itself off of the mounting stud (or boss) and pull out the On the V8, lift off the guide before removing the if it didn't come off with the rocker. It is very important to keep each cylinder's component parts together as an assembly. We suggest drilling a set of holes in a and positioning the pieces in the holes. ENGINE MECHANICAL-GM V6 AND V8 ENGINES Fig. 21 Exploded view of the rocker arm assembly (most V8 engines use a shoulder bolt) To install: 5. Clean and inspect the rocker assemblies. If any scuffing, wear or obvious deterioration is found replace the entire assembly (rocker, ball and and guide if equipped). Roll each push rod across a flat, even surface (countertops work great for this); if it does not roll smoothly, replace it. 6. Coat all bearina surfaces of the rocker assemblv with enaine oil. 7. Slide the into their holes. Make sure ihat seats in its socket on the lifter. 8. On engines, position the guide over the rod so the other side is sitting on the boss. 9. Position the rocker arm over the stud (boss) so that the cupped side rides on the push rod, Slide the ball over the stud, install the nut or bolt and tighten it to: 40 ft. Ibs. (54 Nm) on 1992-96 engines 20 ft. Ibs. (27 Nm) on 1997-98 engines 40 ft. (54 Nm) on engines, except 1998 45 ft. Ibs. (61 on 1998 engines 10. No additional adjustment of the valves is necessary as the lash is set automatically when the rocker is tightened to specifications. 11. Install the cylinder head cover, connect the battery cable and check the idle speed. 1986-91 V6, 1986-98 V8 Engines 4 See Figures and 23 Open or remove the engine hatch cover and disconnect the negative battery cable. Remove the cylinder head cover as detailed previously. 2. Bring the piston in the No. cylinder to If servicing only one arm, bring the piston in that cylinder to TDC. The No. 1 cylinder on is the first cylinder at the port side of the engine. 3. Loosen and remove the rocker arm nuts and lift out the balls. 4. Lift the arm itself off of the mounting stud and pull out the It is very important to keep each cylinder's component parts together as an 5. Clean and inspect the rocker assemblies, particularly the balls where they mate with the rockers. 6. Coat all bearing surfaces of the rocker assembly with engine oil. 7. Slide the push rods into their holes. Make sure that each rod seats in its socket on the lifter. 8. Position the rocker arm over the stud so that the cupped side rides on the push rod. Slide the ball over the stud, install the nut and tighten it until zero lash is present. 9. Adjust the valves as detailed in the Valve Adjustment section. assembly. We suggest drilling a set of holes in a pieces in the holes. and positioning the On certain engines, the exhaust valve those for the intake valve. are longer then To install: Install the cylinder head cover, connect the battery cable and check the idle speed. VALVE ADJUSTMENT 1986-91 V8 And 1998 V8 Engines 4 See Figure 24 These engines utilize hydraulic valve lifters, although there is no need for periodic valve adjustment, it is necessary to perform a preliminary adjustment after any work on the valve assembly. All adjustment should be undertaken while the lifter is on the base circle of the camshaft lobe for that particular cylinder. This means the opposite side of the pointy part of each lobe. Rotate the crankshaft, or bump the engine with the starter until the No. cylinder is at TDC. Note that the notch or mark on the damper pulley will be lined up with the mark on the timing scale. Be careful here though, this could mean that either the No. 1 or the No. 6 (No. 4, V6) piston is at TDG. Place your hand on the No. 1 cylinder's valve and check that it does not move as the mark on the pulley is approaching the mark on the tab. If it does not move, you're ready to proceed; if it does move, you are on the No. 6 (No. 4) cylinder and need to rotate the engine an additional full turn. This is important so make sure you've gotten it 2. Now that the No. 1 cylinder is at TDC, you can adjust the following valves on engines: No.Icylinder: intake and exhaust No. 2 cylinder: intake No. 3 cylinder: intake No. 5 cylinder: exhaust No. 6 cylinder: exhaust Or these valves on engines: No. 1 cylinder: intake and exhaust No. 2 cylinder: intake No. 3 cylinder: exhaust Fig. 22 Wouldn't it be nice if your valve train looked this good? Fia. 23 Close-up of the rocker assembly 5-10 ENGINE MECHANICAL-GM V6 AND V8 ENGINES No. 4 cylinder: exhaust No. 5 cylinder: intake No. 7 cylinder: intake No. 8 cylinder: exhaust 3. Loosen the adjusting nut on the rocker until you can feel lash (play in the push rod) and then tighten the nut until the lash has been removed. Carefully jiggle the push rod while tightening the nut until it won't move anymore-this is zero lash. Tighten the nut an additional full turn (314 turn for the 1988-91 big block) to set the lifter and then you're done. Perform this procedure on each of the valves listed above. 4. Slowly rotate the engine an additional full turn and this will bring the No. 6 (No. 4 on piston to TDC. The pulley notchlmark should once again be in line with the on the timing tab. You can now adjust the remaining valves as you just did on the first pass: No. 2 cylinder: exhaust No. 3 cylinder: intake No. 4 cylinder: intake and exhaust No. 5 cylinder: intake No. 6 cylinder: intake Or these valves on engines: No. 2 cylinder: exhaust No. 3 cylinder: intake No. 4 cylinder: intake No. 5 cylinder: exhaust No. 6 cylinder: intake and exhaust No. 7 cylinder: exhaust No. 8 cylinder: intake 1992-98 V8 And 1998 V8 Engines No initial valve lash adjustment is necessary on these engines; net lash is set when tightening the rocker arm nut or shoulder blot to the proper torque. The rocker studs on engines with nuts are equipped with 'positive stop' shoulders. REMOVAL INSTALLATION See Figures 25 thru Although all engines covered here are equipped with hydraulic lifters, some utilize conventional flat lifters, while others will be equipped with roller lifters. Procedures for each type are different, yet similar enough that we will cover them both within this procedure. 1. Using compressed air, thoroughly clean all dirt and grit from the cylinder head and related components. If compressed air is not available, we highly recommend that you DO NOT proceed with this procedure. It is EXTREMELY important that no dirt gets into the lifter recesses before completing the installation. 2. Remove the cylinder head cover. 3. Remove the intake and exhaust manifolds. 4. Loosen the rocker arms and pivot the rockers off of the pushrods; or just remove them completely. 5. Remove the from the block, being very careful to keep track of where each one came from. 6. Remove the splash shield on 1998 engines. 7. On V6 and certain later engines, loosen and remove the mounting bolts (two or four) and then lift off the lifter guide retainer, with the restrictorslguides. It is a good idea to mark the front side of the retainer for proper installation later on. Not all engines utilize a guide retainer or restrictorslguides in all years, but it will be obvious whether or not your particular engine has them. 8. Remove the lifters. Although they should come right out, you may want to use a magnet, or in some cases on later engines you will need to use a lifter extractor tool or J-3049-A) to extract each lifter. On engines with roller lifters and lifter guides, it is important that the two match each other and that the roller rolls in the same direction as when it was removed; for this reason we think it's a good idea to match mark each lifter to its guide prior to removing it. Fig. 24 Wiggle the push rod slowly while tightening the rocker arm adjusting nut Once again, we suggest using a 2x4 with holes drilled in it to store the rods and lifters; you'd be amazed at how quickly this job will fall apart if someone walks in and kicks the components that you have laid out on the floor! To install: 9. Clean all components thoroughly and let dry completely, use compressed air if at all possible. 10. Make sure that the push rod oil passages are clean and clear. Inspect the camshaft contact surface on the bottom of each lifter for excessive wear, galling or other damage. Discard the lifter if any of the above conditions are found. You'll probably want to check out the camshaft lobe for damage also. 11. Coat the bottom of each flat lifter with but on models with roller lifters use GM Engine Oil Supplement, and then carefully install each one into its respective recess. 12. lnstall the retainer, with restrictorslguides if equipped, and tighten the bolts to 12 ft. Ibs. (16 Nm) on V6 engines, 18 ft. (25 Nm) on V8 engines and 20 Ibs. (26 Nm) on the big blocks. Make sure that the marks you made across the roller lifters and their guides match up and that the mark you made on the retainer is toward the front of the engine!! On engines with restrictorslguides, the retainer MUST contact ALL guides. If bent, and it does not make contact, replace it with a new one. DO NOT attempt to bend it back into position. 13. lnstall the into the sockets on the lifters. Install the splash shield on the Gi. 14. Move the rockers into position and then tighten the nut as detailed in your engine's respective Rocker Arm procedure as detailed previously. lnstall the intake and exhaust manifolds. 16. Install the cylinder head cover. If any, or all, of the lifters has been replaced with a new one it is very important that you add GM Engine Oil Supplement to the crankcase BEFORE starting the engine. ENGINE MECHANICAL-GM V6 V8 ENGINES 5-11 Fig. 25 A good look at the lifter, retainer and push rod1986- 96 V6 engines Fig. 26 The lifter retainer on models is slightly different ... V6 Fia. 27 ...as is the retainer on a V8 Fig. 28 A simple magnet is a good way to remove the lifter (note the set-up for storing them!) ... Fig. 29 ...although later models will require a special tool Fig. 30 Valve lifter retainer and guides on a V8 (V6 simliar) Fig. 31 Notice the guide and the socket in the lifter 5-12 ENGINE MECHANICAL-GM V6 AND V8 ENGINES Fig. 32 The lifter should come out easily ... Fig. 33 ...and look like this (roller lifter shown) REMOVAL INSTALLATION Engines See Figures 34 thru 40 1. Open or remove the engine compartment hatch. the negative battery cable. 2. Loosen the clamp and remove the crankcase ventilation or PCV hoses at the cylinder head covers. Carefully move them out of the way. 3. Drain all water from the cylinder block and manifolds. 4. Tag and disconnect all water hoses at the manifold and thermostat housing. Have some rags handy, since there will still be some water in them. Carefully move them out of the way. 5. Remove the flame arrestor and then disconnect the throttle cable at the carburetorlthrottle body anchor block. 6. Disconnect the fuel line and the line end and the body. If you have a non-flexible it at the fuel pump also. Move both the cable and fuel line out of the wav. 7. Tag and disconnect the lead at the gauge sender unit. Do the same with the harness connected to the rear of the alternator. Tag and disconnect any other lines, leads or hoses that might be in the way of removal. In some instances you may be able to simply secure them out of the way without disconnecting them-you be the judge. 8. If your engine has a spark plug wire retainer attached to the cylinder head cover, the wires or remove the retainer and then tag and disconnect the plug wires at the spark plugs. 9. Remove the distributor cap with the leads still connected. Mark the position of the distributor rotor to the distributor body. Scribe a matchmark across the distributor and the manifold. Loosen the clamp bolt and remove the distributor. Please refer to the Electrical section for further details on distributor removal. DO NOT turn the engine over once the distributor has been removed. 10. Remove the alternator and its mounting bracket. 11. Tag and disconnect any leads at the ignition module and move them out of the way. 12. Tag and disconnect the wire at the oil sending unit and then remove the unit itself. 13. Loosen and remove the manifold mounting bolts in the reverse order of the illustrated tightening sequence and then remove the manifold. Don't forget the solenoid bracket. There is a good likelihood you will need to pry the manifold off the block; be very careful that you don't scratch or mar the mating surfaces on the block, manifold or heads. To install: 14. Carefully remove all remaining gasket material from the manifold mating surfaces with a scraper or putty knife. Be careful that you don't accidentally drop any old gasket into the crankcase or intake ports on the cylinder head. 15. Inspect the manifold and all mating surfaces for any cracks or nicks. 16. On engines, position new seals on the cylinder block mating surfaces. Position new gaskets on the cylinder head mating surfaces. Use GM Silicone Rubber Sealer at all water passages wherever a seal butts against a gasket. Some engines may not have front or rear cylinder block seals. If yours is one of them, apply a in. bead of RTV sealant to the forward and aft edges of the cylinder block mating surface. Make sure that you run the bead at least a 112 in. up onto the gaskets. 17. On 1997-98 engines, coat the cylinder head side of the gasket with RTV sealant. DO NOT apply too much sealer-see the illustration. Position the gaskets onto the heads over the 18. Apply a 112 in. bead of RTV sealant to the forward and aft edges of the cylinder block mating surface. Make sure that you run the bead at least a 112 in. up onto the gaskets. 19. On all engines, install the manifold into place so that all the bolt holes line up, insert the bolts and tighten them to: 30 ft. Ibs. (41 Nm) on 1986-95 engines 35 ft. Ibs. (48 Nm) on 1996 engines 11 ft Ibs. (15 Nm) on 1997-98 engines. This is final torque, so be sure you check the Specifications chart for the first two stages. Fig. 34 lntake manifold tightening engines Fig. 35 lntake manifold tightening sequence1996 engines Fig. 36 lntake manifold tightening engines ENGINE MECHANICAL-GM V6 AND V8 ENGINES Fig. 38 Coat the cylinder head side of the sealer) along the cylinder block-to-manifold gasket with RTV sealant-1997-98 engines the forward block-to-manifold mating mating surfaces-1986-96 enaines surface-1997-98 engines Fig. 37 Make sure to use new seals (or Fig. 39 Run a bead of sealant as shown on Fig. 40 Run a bead of sealant as shown on the aft block-to-manifold mating surface--1997-98 engines (0.50") Check the Torque Specifications chart for any further details on tightening needs. Tighten all bolts in the order shown in the illustration. On all 1997-98 engines, coat all eight bolts with thread locking sealant prior to installing them; remember also that these engines utilize a three step tightening process. 20. lnstall the oil sendina unit and connect the wire. 21. Connect the leads and install the distributor as detailed in the section. Put the cap back on and reconnect the plug wires to the spark plugs. 22. lnstall all water hoses and tighten their clamps securely. 23. lnstall the fuel line at the carburetorlthrottle body and fuel pump. Make sure you remove any plugs you may have inserted on removal. 24. lnstall the throttle cable and adiust it as detailed in the Fuel Svstem section. lnstall the flame arrestor. 25. Connect all other lines, leads and hoses that may have been removed to facilitate manifold removal. 26. lnstall the alternator and mounting bracket. Reconnect the harness 27. Connect the battery cable and start the engine. Check the ignition timing and idle speed. Check all hoses and seals for leaks. And V8 Engines See Figures and 46 1. Open or remove the engine compartment hatch. Disconnect the negative battery cable. 2. Loosen the clamp and remove the crankcase ventilation or PCV hoses at the cylinder head covers. Carefully move them out of the way. 3. Drain all water from the cylinder block and manifolds. 4. Tag and disconnect all water hoses at the manifold and thermostat housing. Have some rags handy, since there will still be some water in them. Carefully move them out of the way. 5. Remove the flame arrestor and then disconnect the throttle cable at the carburetorlthrottle body anchor block. 6. Disconnect the fuel line and plug the line end and the rail fitting. If you have a non-flexible line, disconnect it at the fuel pump also. Move both the cable and fuel line out of the way. 7. Tag and disconnect the lead at the temperature gauge sender unit. Do the same with the harness connected to the rear of the alternator. Tag and disconnect any other lines, leads or hoses that might be in the way of removal. In some instances you may be able to simply secure them out of the way without disconnecting them-you be the judge. 8. If your engine has a spark plug wire retainer attached to the cylinder head cover, unclip the wires or remove the retainer and then tag and disconnect the plug wires at the spark plugs. 9. Remove the distributor cap with the leads still connected, Mark the position of the distributor rotor to the distributor body. Scribe a matchmark across the distributor and the manifold. Loosen the clamp bolt and remove the distributor. Please refer to the Electrical section for further details on distributor removal. DO NOT turn the engine over once the distributor has been removed. 10. Remove the alternator and its mounting bracket. 11. Tag and disconnect any leads at the ignition module and move them out of the way. 12. Tag and disconnect the wire at the oil sending unit and then remove the unit itself. 13. Loosen and remove the manifold mounting bolts in the reverse order of the illustrated tightening sequence and then remove the manifold. Don't forget the solenoid bracket. There is a good likelihood you will need to pry the manifold off the block; be very careful that you don't scratch or mar the mating surfaces on the block, manifold or heads. To install: 14. Carefully remove all remaining gasket material from the manifold mating surfaces with a scraper or putty knife. Be careful that you don't accidentally drop any old gasket into the crankcase or intake ports on the cylinder head. 15. Inspect the manifold and all mating surfaces for any cracks or nicks. 16. On 1992-97 engines (exc. 1997 position new seals on the cylinder block mating surfaces. Position new gaskets on the cylinder head mating surfaces. Use GM Silicone Rubber Sealer at all water passages wherever a seal butts against a gasket. Some engines may not have front or rear cylinder block seals. If yours is one of them, apply a 3116 in. bead of RTV sealant to the forward and aft edges of the cylinder block mating surface. Make sure that you run the bead at least a 112 in. up onto the gaskets. 17. On 1997 and all 1998 engines, coat the cylinder head side of the gasket with RTV sealant. DO NOT apply too much sealer-see the illustration. Position the gaskets onto the heads over the pins. 18. Apply a in. bead of RTV sealant to the forward and aft edges of the cylinder block mating surface. Make sure that you run the bead at least a 112 in. up onto the gaskets. 5-14 ENGINE V6 AND V8 ENGINES FRONT Fif. 41 Intake manifold tightening sequence-1992-97 engines except the 1997 Fig. 44 Coat the cylinder head side of the gasket with RTV sealant-1997 and all 1998 enaines Fig. 42 Intake manifold tightening sequence--1997 and 1998 engines Fig. 45 Run a bead of sealant as shown on the forward block-to-manifold mating and all 1998 enaines. Fig. 43. Make sure to use new seals (or sealer) along the cylinder block-to-manifold mating surfaces-1992-97 engines except the 1997 (0.50") Fig. 46 Run a bead of sealant as shown on the aft block-to-manifold mating 1997 and all 1998 enaines 19. On all engines, install the manifold into place so that all the bolt holes line up, insert the bolts and tighten them to: 30 ft. (41 Nm) on 1986-97 engines 11 ft (15 Nm) on 1997 and 1998 engines. This is final torque, so be sure you check. This is final torque, so be sure you check the Specifications chart for the first two stages-27 inch (3 Nm) on the first pass, 106 inch Ibs. (12 Nm) on the second. Check the Torque Specifications chart for any further details on tightening needs. Tighten all bolts in the order shown in the illustration. On all 1998 engines (yes, this also goes for the 1997 coat all eight bolts with thread locking sealant prior to installing them; remember also that these engines utilize a three step tightening process. lnstall the oil sending unit and connect the wire. 21. Connect the ignition module leads and install the distributor as detailed in the Electrical section. Put the cap back on and reconnect the plug wires to the spark plugs. lnstall all water hoses and tighten their clamps securely. 23. lnstall the fuel line at the body and fuel pump. Make sure you remove any plugs you may have inserted on removal. 24. lnstall the throttle cable and adjust it as detailed in the Fuel System section. lnstall the flame arrestor. 25. Connect all other lines, leads and hoses that may have been removed to facilitate manifold removal. 26. Install the alternator and mounting bracket. Reconnect the harness. 27. Connect the battery cable and start the engine. Check the ignition timing and idle speed. Check all hoses and seals for leaks. And V8 Engines (Except 1997-9 See Figures 47 thru 52 Open or remove the engine compartment hatch. Disconnect the negative battery cable. 2. Loosen the clamp and remove the crankcase ventilation or PCV hoses at the cylinder head covers. Carefully move them out of the way. 3. Drain all water from the cylinder block and manifolds. 4. Remove the flame arrestor cover. Remove the flame arrestor itself and then disconnect the throttle cable at the carburetor anchor block. 5. Disconnect the electrical leads and remove the alternator. 6. Tag and disconnect all water hoses at the manifold and thermostat housing. Have some rags handy, since there will still be some water in them. Carefully move them of the way and then remove the thermostat housing. 7. Disconnect the fuel line and plug the line end and the carburetor fitting. If you have a non-flexible line, disconnect it at the fuel pump also. Move both the cable and fuel line out of the way. 8. Tag and disconnect the wire at the choke housing. 9. Unplug the main harness at the connector block. Disconnect it from the retaining clips and move it out of the way. 10. Tag and disconnect any other lines, leads or hoses that might be in the way of removal. In some instances you may be able to simply secure them out of the way without disconnecting them-you be the judge. 11. If your engine has a spark plug wire retainer attached to the cylinder head cover, unclip the wires or remove the retainer and then tag and disconnect the plug wires at the spark plugs. 12. Remove the distributor cap with the leads still connected. Mark the position of the distributor rotor to the distributor body. Scribe a matchmark across the distributor and the manifold. Loosen the clamp bolt and remove the distributor. Please refer to the Electrical section for further details on distributor removal. DO NOT turn the engine over once the distributor has been removed. Tag and disconnect any leads at the ignition module and move them out of the way. 14. Loosen and remove the manifold mounting bolts in the reverse order of the illustrated tightening sequence and then remove the manifold; no need to separate the carburetor unless you are replacing the manifold. There is a good likelihood you will need to pry the manifold off the block; be very careful that you don't scratch or mar the mating surfaces on the block, manifold or heads. ENGINE MECHANICAL-GM V6 AND V8 ENGINES 5-15 Fig. 47 lntake manifold tightening Fig. 48 lntake manifold tightening Fig. 49 lntake manifold tightening engines engines sequence1 992-95 engines FRT FRONT Front FRT FRT Fig. 50 lntake manifold tightening Fig. 51 lntake manifold tightening Fig. 52 Installing the intake manifold and sequence-1 996-97 engines engines gaskets To install: 15. Carefully remove all remaining gasket material from the manifold mating surfaces with a scraper or putty knife. Be careful that you don't accidentally drop any old gasket into the crankcase or intake ports on the cylinder head. 16. Inspect the manifold and all mating surfaces for any cracks or nicks. 17. Position new seals on the cylinder block mating surfaces, Position new gaskets on the cylinder head mating surfaces-make sure the gaskets have the metal inserts covering the center exhaust port. Use GM Silicone Rubber Sealer at all water passages wherever a seal butts against a gasket. Some engines may not have front or rear cylinder block seals. If yours is one of them, apply a 3116 in. bead of RTV sealant to the forward and aft edges of the cylinder block mating surface. Make sure that you run the bead at least a 112 in. up onto the gaskets. 18. install the manifold into place so that all the bolt holes line up, insert the bolts and tighten them to: 30 ft. Ibs. (41 Nm) on engines. 35 ft. Ibs. (47 Nm) on engines Check the Torque Specifications chart for any further details on tightening needs. Tighten all bolts in the order shown in the illustration, 19. Connect the ignition module leads and install the distributor as detailed in the Electrical section. Put the cap back on and reconnect the plug wires to the spark plugs. 20. lnstall all water hoses and tighten their clamps securely. 21. lnstall the fuel line at the carburetor and fuel pump. Make sure you remove any plugs you may have inserted on removal. 22. lnstall the throttle cable and adjust it as detailed in the Fuel System section. lnstall the flame arrestor and cover. 1997-98 V8 Engines Upper Manifold (Plenum) See Figures 53 thru 59 Open or remove the engine compartment hatch. Disconnect the negative battery cable. 2. Relieve the fuel system pressure as detailed in the Maintenance or Fuel System sections. 3. Loosen the clamp and remove the crankcase ventilation or PCV hoses at the cylinder head covers. Carefully move them out of the way. 4. Remove the flame arrestor cover. Remove the flame arrestor itself and then disconnect the throttle cable at the throttle body bell crank. 5. Tag and disconnect the electrical leads at the following: ECM and Knock sensor module Throttle position sensor IAC valve MAP sensor 6. Tag and disconnect the hose from the pressure regulator at the nipple on the port side of the plenum (1997 and 1998 7. Tag and disconnect the vapor at the pulse limiter on the port side, rear. 8. Loosen the mounting bolts (8 or 12) in the reverse order of the illustrated tightening sequence and lift off the plenum. Make sure that you take note of how the throttle and fuel line brackets were positioned. Remove and discard the eight O-rings. 9. Carefully cover the lower manifold port openings to prevent dirt from entering the engine. 23. Connect all other lines, leads and hoses that may have been removed to facilitate manifold removal. 24. lnstall the alternator and mounting bracket. Reconnect the harness. Upper intake plenums are made of aluminum-be extremely careful of 25. Connect the battery cable and start the engine. Check the ignition how you handle it and where you set it down, particularly the mating timing and idle speed. Check all hoses and seals for leaks. surfaces. 5-16 ENGINE MECHANICAL-GM V6 AND V8 ENGINES To install: 12. Coat the new O-rings lightly with grease and insert them into the Fig. 54 Disconnect the throttle linkage Fig. 55 Disconnect the sensor leads ... Fig. 57 Upper intake plenum tightening sequence--1997 and 1998 Fig. 56 ...and the ECM connectors 10. Carefully remove any remaining gasket material from the plenum and manifold mating surfaces. Make sure the O-ring recesses in the lower manifold runners are free of grime and dirt. 11. Clean the inside of the plenum with Carburetor Cleaner or something similar. Do not use anything with methyl ethyl ketone! Never soak the plenum in commercial liquid cleaners or solvents. recesses on the lower manifold. 13. Position the plenum onto the manifold in such a way that you do not dislodae the Coat the threads of the mounting bolts with 777 similar) install them. Tighten the bolts in in several steps, to 124 inch (14 Nm). 14. Connect the pulse limiter hose and tighten the clamp securely. 15. Reconnect all electrical leads previously removed. 16. Reconnect all vacuum lines previously removed. 17. Install the flame arrestor and reconnect the throttle cable. Check for correct throttle operation and adjust if necessary. Connect the battery cables. Fig. 58 Upper intake plenum tightening Fig. 59 intake plenum and sequence--1998 gaskets ENGINE MECHANICAL-GM V6 AND V8 ENGINES 5-17 Lower Manifold See Figures and 61 1. Open or remove the engine compartment hatch. Disconnect the negative battery cable. 2. Drain all water from the cylinder block and manifolds. 3. Remove the upper intake manifold (plenum). 4. Disconnect the electrical leads and remove the alternator. 5. Tag and disconnect all water hoses at the manifold and thermostat housing. Have some rags handy, since there will still be some water in them. Carefully move them out of the way and then remove the thermostat housing. 6. Disconnect the fuel line and plug the line end and the throttle body fitting if not already done. If you have a non-flexible line, disconnect it at the fuel pump also. Move both the cable and fuel line out of the way. 7. Unplug the main harness at the connector block. Disconnect it from the retaining clips and move it out of the way. 8. Tag and disconnect any other lines, leads or hoses that might be in the way of removal. In some instances you may be able to simply secure them out of the way without disconnecting them-you be the judge. 9. If your engine has a spark plug wire retainer attached to the cylinder head cover, the wires or remove the retainer and then tag and disconnect the plug wires at the spark plugs. 10. Remove the distributor cap with the leads still connected. Mark the position of the distributor rotor to the distributor body. Scribe a matchmark across the distributor and the manifold. Loosen the clamp bolt and remove the distributor. Please refer to the Electrical section for further details on distributor removal. DO NOT turn the engine over once the distributor has been removed. 11. Tag and disconnect any leads at the module and move them out of the way. 12. Loosen and remove the manifold bolts in the reverse order of the illustrated tiahtenina seauence and then remove the manifold: no need to separate the unless you are replacing the manifold. is a good likelihood you will need to pry the manifold off the block; be very careful that you don't scratch or mar the mating surfaces on the block, manifold or heads. Fig. 61 Intake manifold tightening sequence-1998To install: 13. Carefully remove all remaining gasket material from the manifold Fig. 60 Intake manifold tightening sequence-all 1997 engines mating surfaces with a scraper or putty knife. Be careful that you don't accidentally drop any old gasket into the crankcase or intake ports on the cylinder head. 14. Inspect the manifold and all mating surfaces for any cracks or nicks. 15. Position new seals on the cylinder block mating surfaces. Position new gaskets on the cylinder head mating surfaces-make sure the gaskets have the metal inserts covering the center exhaust port. Use GM Silicone Rubber Sealer at all water passages wherever a seal butts against a gasket. Some engines may not have front or rear cylinder block seals. If yours is one of them, apply a 3/16 in. bead of RTV sealant to the forward and edges of the cylinder block mating surface. Make sure that you run the bead at least a 112 in. up onto the gaskets. 16. On all engines, install the manifold into place so that all the bolt holes line up, insert the bolts and tighten them to: 30 ft. Ibs. (41 Nm) on engines. 35 ft. Ibs. (47 Nm) on engines Check the Torque Specifications chart for any further details on tightening needs. Tighten all bolts in the order shown in the illustrations. On 1998 Gi engines, coat all bolts with thread locking sealant prior to installing them. 17. Connect the module leads and install the distributor as detailed in the Electrical section. Put the cap back on and reconnect the plug wires to the spark plugs. 18. lnstall all water hoses and tighten their clamps securely. 19. lnstall the fuel line at the body and fuel pump. Make sure you remove any plugs you may have inserted on removal. 20. Connect all other lines, leads and hoses that may have been removed to facilitate manifold removal. 21. lnstall the alternator and mounting bracket. Reconnect the harness. 22. lnstall the upper plenum. 23. Connect the battery cable and start the engine. Check the ignition timing and idle speed. Check all hoses and seals for leaks. REMOVAL INSTALLATION DERATE See Figures and 67 Open or remove the engine compartment hatch. Disconnect the negative battery cable. 2. Drain all water and/or coolant from the engine, manifold and exhaust elbow as detailed in the Maintenance section. 3. Disconnect all lines at the manifold and move them out of the way. It's a good idea to tag these so that you can ensure proper reconnection. Make sure that you have some rags handy, because there will probably be some spillage even though you've already drained the system. 4. Loosen the hose clamps and then disconnect the exhaust pipe hose (bellows) at the elbow and move it out of the way. Grasp the hose with both hands and wiggle it back and forth while pulling it off the elbow. Take note of where all the hose clamps were situated. 5. If you intend to remove the starboard manifold, many engines will have the circuit breaker bracket attached to the elbow, loosen the mounting and remove the circuit breaker bracket (breaker still attached) and position it out of the way. Many later models will also have the ignition module bracket attached to the rear side as well; detach it and move it aside. 6. If you intend to remove the port elbow on EFI models, remove the fuel reservoir water hose and position it out of the way. 7. Also on the port elbow, all models with remote oil filters will have the filter bracket attached to the forward side of the elbow-be sure you support this carefully when removing the mounting bolts. 8. Remove, disconnect, or simply move out of the way, any hoses or wires which may be in the way of removal on your particular engine. 9. Loosen the manifold retaining from the center outward and then pry off the assembly. 5-18 ENGINE MECHANICAL-GM V6 AND V8 ENGINES Drain Bolt Gasket Pipe Fig. 62 Exploded view of the exhaust system on a typical V8 engine ENGINE MECHANICAL-GM AND Fig. 63 The port exhaust manifold uses 4 mounting nuts on the V6 ... Fig. 64 ...as does the starboard side. Note that these engines did Fig. 65 Close-up of the manifold and related components--except engines not use an elbow until 1991 Elbow Fig. 66 The module bracket is held in place by one of the elbow mounting bolts on certain later models 10. If necessary, loosen the four bolts and remove the exhaust elbow (except 1986-90 V6) from the manifold. To install: Carefully clean all residual gasket from the head, and elbow mating surfaces with a scraper or putty Inspect all gasket surfaces for scratches. cuts or other 12 a new gasket, without any sealant, on the head and the mandold, makrng sure that everything properly Trghten all nuts until they are just tight and then them to 18-22 ft Ibs Nm) on the 1986-90 4 3L V6 and 20-26 Ibs. (27-35 Nm) on 1991-98 V6 and all V8 engines, starting the center, and workrng your way out to the ends of the manifold. On 7 4U8 2L trghten any bolts to 24-28 ft Ibs (33-38 Nm) 13 If you removed the elbow, a new gasket on the mandold, sure that the line up (on seawater cooled and then the elbow Tighten the mounting bolts to 10-12 ft. Ibs (14-16 Nm) on 1986-93 or 12-18 ft Ibs (16-24 Nm)on 1994-98 engines, refer to the Exhaust Elbow procedures found later for more on the elbow. 14 Connect the exhaust to the elbow and tighten the clamps securely 15. If you removed the or elbow plugs for some reason, make sure that the threads are coated sealant before them back 16 Connect the waterlcoolant hoses and the clamps securely 17 Make sure that any miscellaneous or hoses that you may have moved or during removal are reconnected and routed properly. 18 the system wrth water or coolant, connect the battery cable and start the engine When the reaches normal operating temperature, turn it off and re-torque the manifold bolts Fig. 67 On models with a remote oil filter, the filter bracket is secured by the two forward mounting bolts 5-20 ENGINE MECHANICAL-GM V6 AND V8 ENGINES REMOVAL INSTALLATION V6 engines did not use a high rise exhaust elbow. 1986-90 1. Drain the cooling system. 2. Loosen the two hose clamps and slide off the exhaust hose (bellows). Grasp it with both hands and pull it off while wiggling it from side to side. If it sticks, drip a little bit of soapy water around the lip. 3. If you intend to remove the starboard elbow, first loosen the mounting bolts and remove the circuit breaker bracket (if equipped) and position it out of the way. Many later models will also have the ignition module bracket attached to the rear side as well; detach it and move it aside. 4. If you intend to remove the port elbow on EFI models, remove the fuel reservoir water hose and position it out of the way. 5. Also on the port elbow, all models with remote oil filters will have the filter bracket attached to the forward side of the elbow-be sure you support this carefully when removing the mounting bolts. 6. Remove the four bolts, lock washers and washers from the elbow and lift it off the manifold. A little friendly persuasion with a soft rubber mallet may be necessary! Be careful though, no need to take out all your aggressions on the poor thing. 7. Remove the gasket and discard it. To install: 8. Clean the mating surfaces of the manifold and elbow thoroughly, coat both sides of a new gasket with Gasket Sealing compound and position it onto the manifold flange. 9. the elbow on the manifold so the bolt holes are in alignment. Position any anchor brackets or mounting hardware for other components and then install the four mounting bolts and their washers. Tighten the mounting bolts to 10-12 ft. Ibs. (14-16 Nm) on 1986-93 engines or 12-18 ft. lbs. (16-24 Nm) on 1994-98 engines. 10. Slide the exhaust hose, while wiggling it, all the way onto the elbow. Position the two clamps in their channels and tighten the clamp screws securely. Coating the inside of the hose with a soapy water solution will help you slip it on. REMOVAL INSTALLATION See Figures and 69 Not all engines will use an intermediate pipe between upper bellows and the lower exhaust pipe. 1. Starting with the upper hose, loosen all four hose clamps, two on top of the hose and two on the bottom. 2. Drizzle a soapy water solution over the top of the hose where it mates with the exhaust elbow and let it sit for a minute. 3. Grasp the hose with both hands and wiggle it side-to-side while pulling down on it until it separates from the elbow (or the top of the manifold on early V6 engines). 4. Now wiggle it while pulling upwards until it pops off the intermediate exhaust pipe. 5. The lower hose should be removed in the same manner as the upper. 6. Check the hose for wear, cracks and deterioration. 7. Coat the inside of the lower end of the lower hose with soapy water and wiggle it into position on the Y-pipe (lower). Remember to install the two clamps before sliding it over the end of the pipe. There is a step about 1 in. into the inside of one end on each the upper and lower hoses; upper only on the engines. The stepped side of BOTH hoses should fit over the intermediate pipe. This means that the stepped side on the upper hose faces DOWN, and the stepped side on the lower hose faces UP! 8. Slide the two clamps over the upper end of the lower hose and then coat the inside with the soapy water solution and insert the bottom of the intermediate pipe into it fully until it seats on the step. Tighten the clamp screws securely. 9. Coat the inside of the lower end of the upper hose with soapy water and wiggle it into position on the intermediate pipe until it meets the step. Remember to install the two clamps before sliding it over the end of the pipe. 10. Slide two clamps over the upper end, lubricate the inside with soapy water and wiggle the hose over the elbow. Tighten all four clamp screws securely. REMOVAL INSTALLATION See Figure 62 CULT 1. It is unlikely you will be able to get the pipe off without removing the engine, so remove the engine as previously detailed. 2. Loosen the four retaining bolts at the transom shield and then remove the exhaust pipe. Carefully scrape any remnants of the seal from the pipe and transom mounting surfaces. The pipe mounting holes in the transom shield utilize locking inserts. Never clean the holes or threads with a tapping tool or you risk damaging the locking feature of the threads. 3. Coat a new seal with 3M Rubber Adhesive and position it into the groove on the transom shield mating surface. Fig. 68 A good look at the upper hose ... Fig. 69 ...and the lower hose-not all engines will have the bulge in the lower hose like shown here ENGINE MECHANICAL-GM V6 AND V8 ENGINES 5-21 4. Coat the mounting bolts with Gasket Sealing Adhesive. Position the exhaust pipe, insert the bolts and tighten them to 10-12 ft. Ibs. (14-16 Nm) on engines or 20-25 ft. Ibs. (27-34 Nm) on engines. 5. lnstall the engine. EXHAUST VALVE (FLAPPER) REPLACEMENT DERATE Remove the exhaust hoses and the intermediate pipe. The flapper is located in the upper end of the y-pipe. 2. The valve is held in place by means of a pin running through two bushings in the sides of the pipe. Position a small punch over one end of the pin and carefully press the pin out of the pipe. Make sure you secure the valve while removing the retaining pin so it doesn't fall down into the exhaust pipe. 3. Press out the two bushings and discard them. Coat two new bushings with Scotch Grip Rubber Adhesive and press them back into the sides of the pipe. 4. Position the new valve into the pipe with the long side DOWN. When looking at the valve, the molded retaining rings are off-center-the side with the rings should face the top of the pipe. When the valve is in place, coat the pin lightly with engine oil and slowly slide it through one of the bushings, through the two retaining holes on the valve and then through the opposite Make sure the pin ends are flush with the sides of the pipe on both sides. 5. lnstall the exhaust hose. REMOVAL INSTALLATION 1986-96 V6 and 1986-97 V8 Engines (Except 1997 CULT More times than not, this procedure will require the removal of the engine. Your boat and its unique engine installation will determine this, but the procedure is almost always easier with the engine removed from the boat. Remove the engine as previously detailed in this section. 2. If you haven't already drained the engine oil, do it now. Make sure you have a container and lots of rags available. 3. Remove the oil dipstick and then remove the dipstick 4. Remove the oil withdrawal tube from the oil drain plug fitting. 5. Loosen and remove the oil pan retaining bolts and nuts, starting with the center bolts and working out toward the pan ends. Lightly tap the pan with a rubber mallet to break the seal and then lift it off the cylinder block. If your engine stand will allow for rotating the engine, you'll find that this will be easier with the pan facing up. Toinstall: 6. Clean the pan mating surfaces of any residual gasket material with a scraper or putty knife. Make sure that no old gasket material has been pressed into the retaining bolt holes in the pan, block or front cover. Clean the pan itself thoroughly with solvent. 7. Position a new seal into the rear main bearing cap groove and press it into place; make sure that the ends are pressed into the small openings in the cylinder block. 8. Coat new side gaskets lightly with grease and position them so that the aft ends overlap the rear seal and the front ends are pressed into the groove between the timing cover and the cylinder block. 9. lnstall all bolts finger tight and then tighten the front and rear 5116 in. bolts to 12-15 ft. Ibs Ibs. (16-20 Nm) and the remaining 114 in. bolts to 6-7.5 ft. Ibs. Nm). Remember to start with the center bolts and work outward toward the ends of the pan. 10. lnstall the oil drain fitting and finger tighten the bolt. Rotate the fitting and then attach the withdrawal tube. Tighten the fitting bolt and flare nut to 15-18 ft. Ibs. (20-24 Nm). 11. lnstall the engine (if removed). Refill with all fluids. Run the engine up to normal operating temperature, shut it off and check the pan for any leaks. 1997-98 V6 Enaines See Figures and 74 More times than not, this procedure will require the removal of the engine. Your boat and its unique engine installation will determine this, but the procedure is almost always easier with the engine removed from the boat. Remove the engine as previously detailed in this section. 2. If you haven't already drained the engine oil, do it now. Make sure you have a container and lots of rags available. 3. Remove the oil dipstick and then remove the dipstick 4. Remove the oil withdrawal tube from the oil drain plug fitting. 5. Loosen and remove the oil pan retaining bolts and nuts, starting with the center bolts and working out toward the pan ends. Lightly tap the pan with a rubber mallet to break the seal and then lift it off the cylinder block. If your engine stand will allow for rotating the engine, you'll find that this will be easier with the pan facing up. Toinstall: Clean the pan mating surfaces of any residual gasket material with a scraper or putty knife. Make sure that no old gasket material has been pressed into the retaining bolt holes in the pan, block or front cover. Clean the pan itself thoroughly with solvent. 7. Apply a small dab of RTV sealer to the joints on either side of the rear oil seal retainer and front cover, position a new pan gasket onto the pan being very careful to line up all the holes-do not use RTV sealant with this gasket other than where noted, Make sure that the sealer is applied at least in. in either direction from each of the four joints. 8. Move the pan and gasket onto the block; don't dawdle here because the RTV sealant applied in the previous step sets up very quickly. It is very important that you ensure all the holes line up correctly. On these engines, proper alignment of the rear edge of the pan and the block is both surfaces are not flush. the transom bracket alignment will not be rigid. 9. lnstall the special straight edge at the rear and slide the pan back against it. lnstall the pan retaining bolts and nuts finger-tight. 10. Check the clearance between the three oil pan-to-bell housing contact points with a feeler gauge. If clearance exceeds 0.010 in. at any of the three points you will need to remove the pan and start over again. Continue this until all three points are within specifications. 11. Now tighten the bolts to 18 ft. Ibs. (25 Nm) and the nuts to 17 ft. Ibs. (23 Nm). Remember to follow the torque sequence shown in the illustration. 12. On all engines again, install the oil drain fitting and finger tighten the bolt. Rotate the fitting and then the withdrawal tube. Tighten the fitting bolt and flare nut to 15-18 ft. Ibs. (20-24 Nm). 13. lnstall the engine (if removed). Refill with all fluids. Run the engine up to normal operating temperature, shut it off and check the pan for any leaks. 1997 And 1998 V8 Enaines ULT See Figures and 76 More times than not, this procedure will require the removal of the engine. Your boat and its unique engine installation will determine this, but the procedure is almost always easier with the engine removed from the boat. Remove the engine as previously detailed in this section. 2. If you haven't already drained the engine oil, do it now. Make sure you have a container and lots of rags available. 3. Remove the oil dipstick and then remove the dipstick 4. Remove the oil withdrawal tube from the oil drain plug fitting. 5. Loosen and remove the oil pan retaining bolts, studs and nuts, starting with the center fasteners and working out toward the pan ends. Lift off the reinforcing strips and then lightly tap the pan with a rubber mallet to break the seal and then lift it off the cylinder block. If your engine stand will allow for rotating the engine, you'll find that this will be easier with the pan facing up. 5-22 ENGINE ENGINES Fig. 70 Apply a little RTV sealant at the joints as shown-front of engine Fig. 71 Apply a little RTV sealant at the joints as shown-rear of engine Fig. 73 ...and then slide it back against the special tool to check pan alignment Fig. 72 Install the oil pan ... To install: 6. Clean the pan mating surfaces of any residual gasket material with a scraper or putty knife. Make sure that no old gasket material has been pressed into the retaining bolt holes in the pan, block or front cover. Clean the pan itself thoroughly with solvent. 7. Apply a small dab of GM Adhesive sealer to the joints on either side of the rear oil seal retainer and front cover, position a new pan gasket onto the pan being very careful to line up all the holes--do not use RTV sealant with this gasket other than where noted. Make sure that the sealer is applied at least in. in either direction from each of the four joints. 8. Move the pan and gasket onto the block; don't dawdle here because the RTV sealant applied in the previous step sets up very quickly. It is very important that you ensure all the holes line up correctly. 9. Position the reinforcing strips on each side and then tighten the bolts, stud or nuts on each corner to 15 ft. (20 Nm); tighten the remaining bolts and studs to 106 inch Ibs. (12 Nm). 10. Install the oil drain plug or the oil drain fitting and finger tighten the bolt. Rotate the fitting and then attach the withdrawal tube. Tighten the fitting bolt and flare nut to 15-18 ft. Ibs. (20-24 Nm). 11. Install the engine (if removed). Refill with all fluids. Run the engine up to normal operating temperature, shut it off and check the pan for any leaks. Fig. 74 Oil pan tightening sequence Remove the engine as previously detailed in this section. 2. If vou haven't alreadv drained the enaine oil, do it now. Make sure vou have container and of 3. Remove the oil dipstick remove the dipstick 4. Remove the oil withdrawal tube from the oil drain fittina. 5. Loosen and remove the oil pan retaining bolts and with the center bolts and working out toward the pan ends. Lightly tap the pan with a rubber mallet to break the seal and then lift it off the cylinder block. If your engine stand will allow for rotating the engine, you'll find that this will be easier with the pan facing up. 6. Lift of the pan reinforcement strips on 1988-91 engines. To install: 7. Clean the pan mating surfaces of any residual gasket material with a scraper or putty knife. Make sure that no old gasket material has been pressed into the retaining bolt holes the pan, block or front cover. Clean the pan itself thoroughly with solvent. On all but the 1998 1988-98 V8 Engines CULT See Figures and 80 More times than not, this procedure will require the removal of the engine. Your boat and its unique engine installation will determine this, but the procedure is almost always easier with the engine removed from the boat. 8. Apply RTV sealer (Silicone Rubber Sealer) to the four corners (front and rear) of new side gaskets. Coat them with sealer and position them onto the cylinder block. 9. Position a new seal into the groove in the rear main bearing cap so that the ends mate evenly with the side gaskets. 10. Position a new front seal onto the bottom of the front cover and press the locating tips into the holes in the cover. Make sure that the ends of the seal mate evenly with the side gaskets. ENGINE MECHANICAL-GM V6 AND V8 ENGINES 5-23 Fig. 75 Install the oil pan with the fasteners in these positions, all not shown are bolts-1997 and 1998 engines Fig. 76 A view of the pan, note the reinforcing strip 11. On engines, install all bolts and nuts finger tight and then tighten the pan-to-front cover bolts to 70 inch (8 Nm) and the remaining bolts to 160 inch Ibs. (18 Nm). On engines, install all bolts and nuts finger tight and then tighten the pan-to-front cover bolts to 120 inch Ibs. (13.6 Nm) and the remaining bolts to 200 inch Ibs. (22.5 Nm). Refer to the tightening sequence illustration for engines; on 1992-93 engines, tighten them evenly and alternately from the center outward. On the 1998 12. Apply RTV sealant to the four places that the front and rear main bearing caps mate with the cylinder block. 13. Position a new gasket and then install the oil pan. Thread in all mounting bolts finger tight and then tighten them to 18 Ibs. (25 Nm), alternately and from the center outward. On all engines: 14. Install the oil drain fitting and finger tighten the bolt. Rotate the fitting and then attach the withdrawal tube. Tighten the fitting bolt and flare nut to 15-18 Ibs. (20-24 Nm); 20 ft. Ibs. (28 Nm) on the 1998 15. Install the engine (if removed). Refill with all fluids. Run the engine up to normal operating temperature, shut it off and check the pan for any leaks. The two-piece oil pump utilizes two pump gears and a pressure regulator valve enclosed in a two-piece housing. A baffled pick-up tube is press-fit into the body of the pump. The pump is driven via the distributor shaft which is itself driven from a gear on the camshaft. Oil passes through the pick-up screen, through the pump and then through the oil filter. REMOVAL INSTALLATION See Figures and 83 1. Remove the oil pan as previously detailed. Remember that you probably need to remove the engine for this procedure. 2. Most V8 engines utilize an oil baffle (deflector) plate; remove the retaining nuts (three, and a bolt) and lift out the baffle. Certain engines also use a baffle that is mounted to the pick-up screen. 3. Loosen and remove the pump mounting from the rear main bearing cap and lift off the pump assembly. 4. Pull out the driveshaft and retainer. 5. Loosen the four pump cover screws and lift off the cover with the screen attached. The oil pump pick-up screen-and pipe are press fit to the pump cover, they are serviced as an assembly so should not be separated; nor should they be replaced during normal service. If the assembly does require replacement, mount the pump in a vise and pull out the pipe. Do not reinstall the same assembly, use only a new replacement. Make sure that the screen is parallel with the bottom of the oil pan. Reinforcina A Strip Fig. 78 Installing the oil pan1992- 98 engines (except 1998 Fig. 79 Installing the oil pan1998 Fig. 77 Installing the oil pan-1988-91 engines 5-24 ENGINE MECHANICAL-GM V6 AND V8 ENGINES 6. Matchmark the two gears where they mesh and then lift out the two gears. Remove the pressure regulator valve and it associated parts. 7. Clean all components in solvent and dry thoroughly. Inspect the pump body and gears for cracks, excessive wear or other damage 8. lnstall the pressure regulator valve into the housing cover with a new spring. 9. Install the retaining pin. 10. lnstall the drive gear into the housing. lnstall the idler gear so that the matchmarks mesh with the drive gear and the smooth side is toward the cover. 11. lnstall the pump cover and tighten the screws to: 6-9 ft. Ibs. (8-12 Nm) on 1986-96 V6 engines 106 inch Ibs. on 1997-98 V6 engines 6-9 Ibs. (8-i2 1986-97 V8 engines (except the 1997 106 inch Ibs. on the 1997 and 1998 V8 engines 80 inch Ibs. (9 Nrn) on all V8 engines (except the 1998 106 inch Ibs. (12 Nm) on 1998 12. Check that the pump and block mating surfaces are clean and then position the pump over the block so that the pump extension shaft tang is aligned with the distributor driveshaft slot. Do not use a gasket or RTV sealant. Tighten the pump mounting bolts to 65 ft. Ibs. (90 Nm) on all but the engine, and 70 ft. Ibs. (95 Nm) on engines Front Fig. 80 Oil pan tightening engines The pump should slide into place easily, if not recheck the alignment of the two shafts. 13. Install the oil baffle on engines so equipped and tighten the nuts to 30 ft. Ibs. (40 Nm). 14. lnstall the oil pan and engine. Almost all engines covered here utilize a bypass valve. After removing the oil filter, check the spring and small fiber valve for proper operation. Any signs of incorrect operation, or wear and deterioration will necessitate replacement. Fig. 81 Oil pump and pick-up screen properly installed on a typical Baffle Plate Oil Pump 82 Most use an oil baffle plate ENGINE MECHANICAL-GM V6 AND V8 Pump Shaft 2 - 8 - Valve -Pump Body Pressure Spring 4 Gear and Plug Gear Pin Pickup Screen and Pipe Screws REMOVAL INSTALLATION See Figure 84 Drain the oil as detailed in the Maintenance section. 2. Remove the oil filter. 3. Using a small remove the valve. 4. Install a new valve and press it in by placing a 9116 in. deep socket over it and tapping the socket lightly with a hammer. 5. Install the oil filter and refill the engine with the appropriate oil. REMOVAL INSTALLATION Over the years, these engines were equipped in a variety of configurations-flywheel and torsional damper, flywheel, damper and coupler, flywheel and coupler, etc. And for a number of years, some models also had a timing ring attached. Early models are usually the ones equipped with a damper, while Cobra, SP and DP models usually were equipped with the coupler. King Cobra models are usually the ones that use the timing ring, although there were also some engines that used it. Although we have attempted to narrow the applications in the following procedures, it was not always year or model specific. Please read the procedures FIRST in order to determine which one is appropriate for your particular engine's configuration. Fig. 84 Oil filter bypass valve 5-26 ENGINE MECHANICAL-GM V6 AND V8 ENGINES Models With A Torsional Damper CULT Over the years, these engines were equipped in a of configurations-flywheel and torsional damper, flywheel, damper and coupler, flywheel and coupler, etc. And for a number of years, some models also had a timing ring attached. Early models are usually the ones equipped with a damper, while Cobra, SP and DP models usually were equipped with the coupler. King Cobra models are usually the ones that use the timing ring, although there were also some engines that used it. Although we have attempted to narrow the applications in the following procedures, it was not always year or model specific. Please read the procedures FIRST in order to determine which one is appropriate for your particular engine's configuration. 1. Remove the engine as detailed previously. 2. Loosen the bolts and remove the flywheel housing and cover plate. 3. Remove the three mounting bolts and pull off the rear torsional damper. 4. Remove four of the six flywheel retaining bolts. Loosen the other two, any two is fine, and back them out about half way. Using the two bolts as a stop, carefully pull the flywheel off of the crankshaft flange. Remove the two bolts and flywheel. To install: 5. Position the flywheel over the dowel pin on the flange and make sure that the holes line up correctly. Coat the bolt threads with engine oil, install them and tighten to 59 ft. Ibs. (82 Nm). Tighten the six bolts in a diagonal star pattern. 6. lnstall the torsional damper and tighten the bolts securely. lnstall the housing and plate. Coat all mounting bolts with engine oil and tighten the 9116 in. housing bolts to 30 ft. Ibs. (41 Nm), the 5116 in. plate bolts securely. 8. Install the engine. Models With A Timing Ring See Figures 86 and 87 Over the years, these engines were equipped in a variety of configurations-flywheel and torsional damper, flywheel, damper and coupler, flywheel and coupler, etc. And for a number of years, some models also had a timing ring attached. Early models are usually the ones equipped with a damper, while Cobra, SP and DP models usually were equipped with the coupler. King Cobra models are usually the ones that use the timing ring (350,454, although there were also some engines that used it. Although we have attempted to narrow the applications in the following procedures, it was not always year or model specific. Please read the procedures FIRST in order to determine which one is appropriate for your particular engine's configuration. 1. Remove the engine from the boat as detailed previously in this section. 2. Loosen and remove any connections attached to either of the ground studs on each side of the flywheel. Move the electrical leads out of the way. 3. Loosen the 5 retaining bolts and slide out the lower housing cover. 4. Although not strictly necessary, we recommend removing the starter. 5. Locate the timing sensor cover on the housing, loosen the two nuts and lift off the cover. Remove the two nuts and washers and then pull out the sensor and position it out of the way. 6. Cut the plastic tie that secures the housing drain hose and the pull the hose out of the fitting. 7. Remove the flywheel housing retaining nutslbolts and pull off the housing. Take note of the positioning of the oil cooler and its bracket. 8. Slide an offset wrench behind the coupler and loosen the six flywheel mounting nuts gradually and as you would the lug nuts on your car or truck- that is, in a diagonal star pattern. Remove the coupler. 9. Mark the dowel hole on the timing ring and pry it off the flywheel. Remove the flywheel. To install: 10. Thoroughly clean the flywheel mating surface and check it for any nicks, cracks or gouges. Check for any broken teeth. 11. lnstall the flywheel over the dowel on the crankshaft. 12. Position the timing ring over the locating pin making sure the pin is in the correct hole-you did mark it, right? Press the ring into position. 13. Slide the coupler over the studs so that it sits in the recess on the flywheel. lnstall new lock washers and tighten the mounting nuts to 40-45 ft. (54-61 Nm). Once again use the star pattern while tightening the bolts. 14. lnstall the flywheel housing and attach the-oil cooler. Tighten the nutslbolts to 32-40 ft. Nm). 15. lnstall the washer, lock washer and inner nut on the ground stud and tighten it to 15-20 ft. Ibs. (20-27 Attach the electrical leads, install another lock washer and then tighten the outer nut securely. 16. Slide the drain hose in and attach it with a new plastic tie. 17. Position the timing sensor onto the mounting studs and press in on the spring tab so that the sensor seats itself correctly over the timing ring. lnstall the washers and nuts, with the tab still depressed, and tighten them to 48-64 inch (5-7 Nm). Once the nuts are tightened, press in on the spring tab again and confirm that the tab DOES NOT touch the timing ring. If it does, loosen the nuts and try it again. If the sensor tab comes in contact with the teeth of the timing ring, it will be damaged on engine start-up. 18. lnstall the sensor and tighten the nuts to 48-64 inch Ibs. (5-7 Nm). 19. Coat both sides of a new gasket with Gasket Sealing Compound and position it onto the cover. Slide the cover into position and tighten the bolts to 60-84 inch Ibs. (7-9 Nm). lnstall the engine. Models With A Coupler See Figures and 87 Over the years, these engines were equipped in a variety of configurations-flywheel and torsional damper, flywheel, damper and coupler, flywheel and coupler, etc. And for a number of years, some models also had a timing ring attached. Early models are usually the ones equipped with a damper, while Cobra, SP and DP models usually were equipped with the coupler. King Cobra models are usually the ones that use the timing ring, although there were also some engines that used it. Although we have attempted to narrow the applications in the following procedures, it was not year or model specific. Please read the procedures FIRST in order to determine which one is appropriate for your particular engine's configuration. Remove the engine from the boat as detailed previously in this section. 2. Loosen and remove any connections attached to either of the ground studs on each side of the flywheel. Move the electrical leads out of the way. 3. Although not strictly necessary, we recommend removing the starter. 4. Loosen the 4 or 5 retaining bolts and slide out the lower housing cover. 5. Cut the plastic tie that secures the housing drain hose and the pull the hose out of the fitting. 6. Remove the oil cooler and bracket, take note of the positioning of both and secure them out of the way. 7. Remove the flywheel housing. 8. Slide an offset wrench behind the coupler and loosen the six flywheel mounting nuts gradually and as you would the lug nuts on your car or truck- that is, in a diagonal star pattern. 9. Remove the coupler and then the flywheel. To install: 10. Thoroughly clean the flywheel mating surface and check it for any nicks, cracks or gouges. Check for any broken teeth. 11. lnstall the flywheel over the dowel on the crankshaft. 12. Slide the coupler over the studs so that it sits in the recess on the flywheel. lnstall new lock washers and tighten the mounting nuts to 40-45 ft. (54-61 Nm) except on 1992 engines where the spec is 35-40 ft. Ibs. 54 Nm). Once again use the star pattern while tightening the bolts. 13. lnstall the flywheel housing and attach the oil cooler. Tighten the bolts to 28-36 ft. Nm) on 1986-91 engines or 32-40 ft. Ibs. (43-54 Nm) on 1992-98 engines. 14. lnstall the washer, lock washer and inner nut on the ground stud and tighten it to 20-25 ft. Ibs. (27-34 Nm) on 1986-91 engines or 15-20 ft. Ibs. (20-27 Nm) on 1992-98 engines. Attach the electrical leads, install another lock washer and then tighten the outer nut securely. 15. Coat both sides of a new gasket with Gasket Sealing Compound and position it onto the cover. Slide the cover into position and tighten the bolts to inch (7-9 Nm). 16. Slide the drain hose in and attach it with a new plastic tie. 17. lnstall the engine. ENGINE MECHANICAL-GM V6 AND V8 ENGINES 5-27 Fig. 85 Remove the cover... Fig. 86 ...and then pull off the coupler after removing the bolts Fig. 87 Tighten the mounting bolts in a criss-cross pattern REMOVAL INSTALLATION V6 And V8 Engines See Figure 88 It is not necessary to remove the engine or rear main bearing cap when removing the one-piece oil seal on these engines although you may find it easier to do just that. A new oil seal must be installed whenever the retainer is removed. 1. Remove the oil pan. 2. Remove the flywheel. 3. Loosen the and then lift out the retainer and gasket. 4. Replace the oil seal. 5. Clean all traces of old gasket material from the mating surfaces and position a new seal on the cylinder block. 6. Install the seal retainer, with a new gasket, and tighten the nutslbolts to 135 inch (15 Nm). 7. Install the oil pan and flywheel as previously detailed. REMOVAL INSTALLATION V6 And V8 Engines Early engines may h two . oil seal. One Piece Seal See Figures and 90 It is not necessary to remove the engine or rear main bearing cap when removing the one-piece oil seal on these engines although you may find it easier just that. Remove the flvwheel housing and cover as detailed in this section. 2. Remove the coupler and flywheel from the engine as detailed in this section. 3. Remove the seal retainer. This is not absolutely necessary. 4. Insert a small into one of the three slots in the edge of the seal retainer and slowly pry the seal out of the retainer. Be very careful not to nick or damage the sealing surface while prying out the seal. 5. Thoroughly clean the retainer surface and then install the retainer. 6. Spread a small amount of engine oil around the inside and outside edges of a new seal and position it into a Seal Driver (7J-35621). 7. Position the driver and seal over the crankshaft and then thread the attaching screws into the holes in the crankshaft, tightening them securely. Turn the handle on the tool until it bottoms out-the seal is now in place. Install the flywheel and engine coupler. lnstall the cover and flywheel housing. TwoPiece Seal See Figures 91 and 92 These engines utilize a two-piece rear main seal. The seal can be removed without removing the crankshaft. You will need to remove the engine for this procedure though. Remove the engine as detailed previously in this section. 2. Remove the oil and pump as detailed previously in this section. 3. Loosen the bolts and remove the rear main bearing cap. Carefully insert a small and remove the lower half of the seal. Do not damage the seal seating surface. Fig. 88 Removing the seal retainer Fig. 89 Use the three slots in the seal retainer when removing the rear main seal Fig. 90 Use a seal driver to seat the new oil ENGINE MECHANICAL-GM AND V8 ENGINES Fig. 91 Fabricate a seal installation tool out of an old feeler gauge ... Fig. 92 ...and then use the tool to feed the seal around the crankshaft -Cut away 4. Using a hammer and a small drift, tap on end of the upper seal until starts to protrude form the other side of the race. Grab the protruding end with pliers and pull out the remaining seal half. 5. Check that you have the correct new seal. Seals with a hatched inner surface can only be used on left hand rotation engines, smooth seals can be used on any engine. Coat the lip and bead with motor oil. Keep oil away from the seal parting surfaces. 6. Your seal kit should come with an installation tool, if not, take a 0.004 in. feeler gauge and cut each side back about a half inch so that you're left with an 11164 inch point. Bend the tool the gap between the crankshaft and the seal seating surface. This will be your "shoe horn". 7. Position the upper half of the seal (lip facing the engine) between the crank and the tool so that the seal's bead is in contact with the tool tip. Roll the seal around the crankshaft using the tool as a guide until each end is flush with the cylinder block. Remove the tool. 8. Insert the lower seal half into the main bearing cap with the lip facing the cap. Start it so that one end is slightly below the edge of the cap and then use the tool to shimmy the all the way in until both edges are flush with the edge of the cap. Remove the tool. 9. Make sure that the caplblock mating surfaces and the seal ends are free of any oil and then apply a small amount of Perfect Seal to the block just behind where the upper seal ends are. 10. lnstall the bearing cap and ttghten the bolts to the correct torque as detailed in the Torque Specifications chart. lnstall the oil pump and pan. 12. lnstall the engine. Engines CULT See Figures 90 and 9 It is not necessary to remove the engine or rear main bearing cap when removing the one-piece oil seal on these engines although you may find it easier to do just that. 1. Remove the flywheel housing and cover as detailed in this section. 2. Remove the engine coupler and flywheel from the engine as detailed in this section. 3. Insert a small into the seal groove and slowly pry the seal out of the groove. Be very careful not to nick or damage the sealing surface while prying out the seal. 4. Thoroughly clean the groove surface. 5. Spread a small amount of engine oil around the inside and outside edges of a new seal and position it into a Seal Driver (J-38841) so that the seal's lip faces the cylinder block. 6. Position the driver and seal over the crankshaft and then thread the attaching screws into the holes in the crankshaft, tightening them securely. Turn the handle on the tool until bottoms out-the seal is now place and you can remove the tool. 7. lnstall the flywheel and engine coupler. Install the cover and flywheel housing. 1-Installation tool 2-Seal 3-Engine block 4-Crankshaft REMOVAL INSTALLATION 1. Disconnect the battery cables. 2. Remove the bracket mounting bolts for the alternator and power steering pump. 3. Drain the engine and manifolds. Loosen the two mounting bolts and remove the seawater pump from the crankshaft. 4. Remove the drive or serpentine as detailed in the Maintenance section. 5. Remove the three bolts and pull off the drive pulley attached to the balancer. 6. Remove the balancer retaining bolt (if equipped) and install the special removal tool onto the damper. Tighten the tool press bolt and remove the damper; don't lose the crankshaft key. OMC suggests that you do not use a conventional gear puller for this procedure. To install: 7. Inspect the crank key and then install it into the shaft. Using a little GM Adhesive will make this easier. 8. Coat the front cover oil seal lip with clean engine oil and then install the damper with a proper tool J-23523-E or 39046). Be sure that you thread the tool into the crankshaft at least 112 in. to protect the threads. In a pinch you can use a block of wood and a plastic mallet, but be careful that the pulley does not shift on its mountings while you're hammering. Or, you can use a large washer and a x 4 in. bolt, but we suggest the Main Fig. 93 These engines do not use a seal retainer ENGINE MECHANICAL-GM V6 AND V8 ENGINES 5-29 9. lnstall the plate, thrust bearing and nut on to the rod. Tighten the nut until it bottoms out and then remove the tool. 10. lnstall the retaining bolt (if equipped) and tighten it to: 60 ft. Ibs. (81 on 1986-90 and engines (except LE and 350) 70 ft. Ibs. (95 Nm) on 1990 5.7 LE and 350 engines 70 ft. (95 Nm) on 1991-96 and engines 74 ft. Ibs. Nm) on 1997-98 V6 and engines 85 ft. Ibs. (1 15 Nm) on engines (except 110 ft. Ibs. (149 on 1998 engines 90 ft. Ibs. (122 Nm) on V8 engines Squirt a little RTV sealant into the crankshaft keyway to guard against oil seepage. lnstall the drive pulley and tighten the bolts to 35 ft. Ibs (48 Nm) on the V6, 43 ft. (58 Nm) on V8 engines. 12. lnstall the driveiserpentine belt and make sure that it is adjusted properly. 13. lnstall the seawater pump. Special Tool Fig. 94 Use a special tool to remove and install the balancer REMOVAL INSTALLATION All Except 1988-91 Engines ERA See Figures 95 and 9 This procedure may require engine removal, depending upon your particular boat. If necessary, remove the engine as detailed previously in this section. 1. Open the drain valves and drain the coolant from the block and exhaust Loosen the alternator and power steering brackets to provide slack, and then remove the drive belts. 2. Remove the oil pan on the not always a bad idea on the other engines either, but OMC suggests that it must be removed on the big block engines. Although we can't recommend it, many people will leave the pan on and cut the seal as detailed in the procedures for the 1988-91 3. Remove the alternator and power steering pump bracket bolts. 4. Remove the water circulation pump. 5. Remove the harmonic balancer and pulley as detailed previously in this section. 6. Loosen the mounting bolts and remove the front cover. 7. If the oil seal needs replacement, pry it out from the front (outer) side of the cover with a small 8. Remove the front cover gasket. To install: 9. Clean all gasket material from the cover and block mating surfaces with a scraper of putty knife. Be careful not to knock any pieces of gasket into the timing assembly. 10. If you removed the oil seal, install a new one with the lip toward the inside of the cover. Position a support under the seal and cover and then press the seal into the cover with the proper tool 1986-93 engines, #J-35468 1992-98 engines and 1994-98 engines). 11. Coat the lip of the oil seal with engine oil. Coat both sides of a new gasket with sealant and then position the gasket onto the engine. lnstall the cover so that all the bolt holes line up; there are dowel pins on the cylinder block that will help alignment. Tighten the bolts to: 80 inch Ibs. on 1986-96 enaines 106 inch (12 on engines 80 inch Ibs. (9 Nm) on 1986-97 engines (except 1992 5.7 LE and 1997 100 Ibs. 1 Nm) on 5.7 LE engines 106 inch Ibs. (12 Nm) on 1997 and all 1998 engines 96 inch on 1992-97 engines 106 inch Ibs. (12 Nm) on 1998 V8 engines 120 inch Ibs. (14 Nm) on engines Don't forget to use new cover on engines a composite cover! 12. lnstall the oil pan. 13. lnstall the harmonic balancer and its pulley. 14. lnstall the circulation pump and its pulley. Pull the belts back on. Check their tension adjustment. 15. lnstall the engine if removed. Add oil and waterlcoolant, start the engrne and check for any leaks. Fig. 95 the front shown, V8 similar 1-Crankcase front cover seal installer 2-Support (to prevent distorting cover) Fig. 96 Make sure the front cover is supported securely before pressing in the oil seal 5-30 ENGINE MECHANICAL-GM V6 AND V8 ENGINES 1988-91 Engines 4 See Figure 97 This procedure may require engine removal, depending upon your particular boat. If necessary, remove the engine as detailed previously in this section. Open the drain valves and drain the coolant from the block and exhaust manifold. Loosen the alternator and power steering brackets (or the idler pulley) to provide slack, and then remove the drive belts. 2. Drain the oil if you haven't already done so. 3. Remove the alternator and power steering pump bracket bolts. 4. Remove the water circulation pump. 5. Remove the harmonic balancer and pulley as detailed previously in this section. 6. Remove the two 7116 in. oil pan-to-front cover bolts. Loosen the 318 in. cover mounting bolts and pry the front cover outward slightly. Insert a razor knife between the cover and block so that it is flush with the inside of the cover and then carefully cut the oil pan seal at each side of the cover. 7. Remove the cover. 8. If the oil seal needs replacement, pry it out from the front (outer) side of the cover with a small 9. Remove the front cover gasket. To install: 10. Clean all gasket material from the cover and block mating surfaces with a scraper of putty knife. Be careful not to knock any pieces of gasket into the timing assembly. 11. If you removed the oil seal, install a new one with the lip toward the inside of the cover. Position a support under the seal and cover and then press the seal into the cover with the proper tool 12. Take a new oil pan gasket and cut out a portion of it equal to that which you cut previously when removing the cover. Coat the oil pan mating surface with RTV sealer and carefully position the cut gasket into the flange. While you have the sealer out, run a small bead along the joints where the three (pan, cover and block) surfaces come in contact with one another. 13. Coat the lip of the oil seal with engine oil. Coat both sides of a new gasket with sealant and then position the gasket onto the engine. lnstall the cover so that all the bolt holes line up; there are dowel pins on the cylinder block that will help alignment. Tighten the cover-to-pan bolts to 8 ft. Ibs. (10 Nm). Tighten the cover-to-block bolts to 6 ft. Ibs. (8 Nm). 14. lnstall the harmonic balancer and its pulley. 15. lnstall the circulation pump and its pulley. Pull the belts back on. Check their tension adjustment. 16. lnstall the engine if removed. Add oil and waterlcoolant, start the engine and check for any leaks. Fig. 97 Use a sharp knife to cut the oil pan seal REMOVAL INSTALLATION DERA TE See Figures 98 and Disconnect the battery cables. 2. Remove the mounting bolts for the alternator and power steering pump brackets. 3. Remove the crankshaft pulley and harmonic balancer as previously detailed in this section. 4. Remove the front cover as previously detailed in this section. 5. Rotate the camshaft slightly so that it creates tension on one side of the timing chain (either side is OK). Find a reference point on the same side of the cylinder block as the side that the timing chain is tight on and then measure from this point to the outer edge of the chain. 6. Rotate the camshaft in the opposite direction until the other side of the chain is tight. Press the inner side of the chain outward until it stops and then measure from your reference point on the cylinder block (obviously, do this from the same side of the chain as you did in the previous step) to the outer edge of the chain. This is timing chain deflection and it should be no more than 0.625 in. If it is more than specification, the chain will require replacement. 7. Look carefully at the camshaft and crankshaft sprockets-you should notice a small indent on the front edge of one of the teeth on each sprocket. Bump the engine over until these two marks are in alignment as shown in the illustration--crank mark at and cam mark at a remote starter will work or you can screw the damper bolt back into the crankshaft and turn it with a wrench. 8. Dab a little paint across one of the chain links and the camshaft sprocket. Loosen the camshaft sprocket retaining bolts (three, although on the certain 1994-98 V6 engines, one will be a nut--don't be concerned if the stud comes out with the nut), grasp the sprocket on each side with the chain still attached and wiggle it off the shaft. It should come off readily, but if not, tap the bottom edge lightly with a rubber mallet. Never rotate the crankshaft once the timing chain has been removed. If moved, you'll risk damage to the pistons valve train. 9. Mount a gear puller over the crankshaft pulley and pull it off the shaft. Don't lose the key. To install: 10. Clean the chain and sprockets in solvent and let them air dry. Check the chain for wear and damage, making sure there are no loose or cracked links. Check the sprockets for cracked or worn teeth. 11. Coat the woodruff key lightly with adhesive and position it on the crankshaft. lnstall the crankshaft sprocket onto the shaft with an installation 12. lnstall the timina chain onto the camshaft so that the marks made during match up. If they do, and you haven't the engine, the timing marks on the two sprockets should also. Hold the sprocketkhain in both hands so the chain is hanging down, engage the chain around the crankshaft sprocket and then slide the cam sprocketkhain onto the camshaft making sure the dowel pin aligns with the hole in the sprocket. Do not force it! On 1994-98 shaft drive gear stud fits through the hole. Tighten the three mounting engines, make sure the balance to: 20 ft. Ibs. (27 Nm) on 1986-93 V6 and V8 (except 1992 5.7 LEI and all enaines inch Ibs. 1992 5.7 LE 21 ft. (28 Nm) on 1994-98 and V8 engines 25 ft. Ibs. (34 Nm) on V8 engines Never force the camshaft sprocket onto the shaft or use a hammer, lest you loosen the rear welch plug. 13. lnstall the front cover, harmonic balancer and water pump pulley. 14. lnstall and adjust the drive belts. 15. lnstall the seawater pump and reconnect the alternator and power steering brackets. ENGINE MECHANICAL-GM V6 AND ENGINES 5-31 Fig. 98 When checking timing chain deflection, find a reference point on the cylinder block and use it for each measurement Fig. 99 The two marks on each of the timing sprockets must be in alignment before removing or installing the timing chain 1-Reference Point Remember that when the timing marks were aligned properly, the No. 4 (or No. 6, V8) cylinder was at TDC so if you removed the distributor for some reason, the rotor should be at the No. 4 (No. 6) post on the cap, NOT at the No. 1 post. REMOVAL INSTALLATION V6 Enaines Onlv See Figures 100,101 and 102 1. Remove the distributor cap and mark the position of the No. 1 cylinder terminal on the side of the housing. Matchmark the housing to the engine and then remove the distributor. 2. Remove the intake manifold. 3. Remove the drive belts and then remove the water circulating pump and its pulley. 4. Remove the harmonic balancer and its pulley. 5. Remove the oil pan. 6. Remove the front cover. 7. Fashion a small wedge out of an old piece of wood and jam it (carefully!) in between the teeth of the balance shaft driven gear and the camshaft drive gear (this is behind the sprocket) to hold the shafts from turning. Loosen, but do not remove, the driven gear bolt-although not on all applications, the chances are very good that this will be a head. 8. Loosen the three camshaft sprocket and then pull off the sprocket with the timing chain attached. Remove the camshaft drive gear. 9. Now you can remove the bolt loosened previously and pull off the balance shaft drive gear. 10. Remove the two mounting bolts from the balance shaft retainer and lift off the plate. You've probably already noticed that these will be fasteners also. 11. Insert a suitable between the rear of the shaft and the cylinder block and carefully shimmy the shaft forward and out of the bearing housing in the rear of the block. Slide the entire shaft out through the front of the block. Be careful not to knock any debris into the inside of the cylinder block. You can also use a soft mallet and carefully tap the front bearing assembly to accomplish this step. To install: 12. Glean the balance shaft in solvent and let it dry completely. Inspect the rear bearing for wear or damage. Inspect the front bearing for excessive side play on the shaft, wear or damage. Check the bearing bore in the front of the cylinder block for scoring. marks aligned 2-Locating pins 13. Lubricate the front and rear bearina with motor oil and then carefullv slide the shaft through the front bore until feeds into the rear bearing. suggests using a Driver Handle and Shaft Installer to accomplish shaft installation, but many technicians simply tap the front edge of the shaft with a plastic mallet until the retaining ring on the front bearing seats against the cylinder block-you make the call as to which option you choose. 14. Install the thrust plate and tighten the two fasteners to 120 inch Ibs. (14 Nm). 15. Position the driven gear onto the balance shaft with the bolt finger tight. Make sure that the timing mark is at the bottom of the gear. 16. Install the camshaft drive gear so that the mark aligns with the one on the balance shaft driven gear (it will be pointing UP). You may have to wiggle the two shafts until you get the marks to align correctly, Install the stud and tighten to 12 ft. Ibs. (16 Nm). 17. Remove the balance shaft drive gear bolt again and coat the threads with Loctite. Screw it in and tighten it to 15 ft. Ibs. (20 Nm); and then turn the bolt an additional 35". 18. Install the timing chain and front cover. 19. Install the intake manifold. CHECKING See Figures 103,104 and 105 If the shaft is out of the engine, you can use a micrometer to take the heel-to-lobe measurement and the side-to-side measurement. Subtract the second measurement from the first to get lobe lift. Most times though, the shaft will still be in the cylinder block so perform the following procedure. 1. Tag and disconnect the electrical connectors at the ignition coil. 2. Remove the cylinder head cover and rocker arms as detailed previously. 3. Using a special adaptor connect a dial indicator so that its tip is positioned on the end of the pushrod-the adaptor should screw onto the end of the rocker stud. 4. Slowly rotate the crankshaft in the direction of engine rotation until the valve lifter is riding on the heel (back side of lobe) of the camshaft lobe. The should be at its lowest point when the lifter is on the heel. A remote starter works well for turning the engine over in this situation. MECHANICAL-GM V6 AND V8 ENGINES 5-32 -Alignment marks Fig. 102 The timing marks on the balance shaft driven gear and the camshaft drive gear must be aligned on installation Fig. 100 Use a wooden wedge to keep the 1-Pry Bar 2-Balance shaft 3-Bearing housing Wedge 2-Driven Gear 3-Drive Gear Fig. 101 Carefully lever the balance shaft balance and camshafts from rotating while forward and out of the cylinder block loosening the retaining bolt. 5. Set the indicator to and then rotate the engine until the is at the highest point of its travel, Camshaft lift should be as detailed in the Engine Specifications chart. 6. Continue rotating the engine until the is back at its lowest position-make sure that the indicator still reads 7. Repeat this procedure for the remaining pushrods. 8. lnstall the rocker arms and adjust the valve clearance. 9. lnstall the cylinder head cover and reconnect the coil leads. REMOVAL INSTALLATION CULT See Figures 106 and 107 Remove the cylinder head covers and rocker assemblies as previously detailed in this section. Remove the pushrods. 2. Remove the intake manifold. 3. Remove the lifter restrictor mounting bolts and lift out the restrictors (if equipped). Matchmark the lifters to their bores and then lift out the valve lifters with a small magnet and store them in a rack with labels so they can be reinstalled in their original locations. 4. Remove the front cover and timing as previously detailed in this section. 5. Remove the fuel pump and push rod on early V6 and small block V8 engines. 6. Remove the inner camshaft drive gear on 1994-98 V6 engines. 7. Remove the thrust 8. Thread two (three on later x 4 in. bolts into the camshaft bolt holes and carefully pull the camshaft out of the cylinder block. You may have to wiggle it back and forth a bit, so be sure you don't lean it up or down or else you could damage the bearings. 9. If the camshaft bearings are to be removed, you will need to remove the flywheel as previously detailed, Although it is not necessary, removing the crankshaft will also facilitate bearing removal, make sure that you move the connecting rods out of the way so they do not interfere with bearing removal. 1986-96 engines: 10. Working from inside the block, drive out the rear cam bearing expansion plug (welch plug). 11. Slide the pilot tool into position in the inner the bearing closest to the center of the engine. 12. lnstall a nut and washer onto the puller screw so that the screw can be threaded into the tool with the nut still extending out the front of the cylinder block. Index the pilot over the screw so that the open end is toward the nut on the puller screw. 14. lnstall the remover so the shoulder is facing the No. 3 bearing and it has sufficiently engaged the threads of the tool. 15. Hold shaft with a wrench while turning the puller nut (front) with another until the bearing comes out. Repeat this procedure for the No. 2 bearing. 16. Now remove the pilot from the shaft, remove the tool and reassemble it on the rear of the engine to remove the No. 4 bearing. 17. Install the remover onto the drive handle so that the shoulder is against the handle. The front and rear bearings can now be driven out from the outside of the block. 1997-98 engines: 18. Working from inside the block, drive out the rear cam bearing expansion plug (welch plug). 19. Insert the camshaft bearing removal tool through the first bearing (front of block) and into the bearing being removed. Make sure the is the correct one for your engine and turn the tool until it has seated into the bearing. 20. Push the centering cone up against the cylinder block and into the recess of the No. 1 bearing so that the tool centers itself. Drive the bearing out of the block. 21. Repeat the procedure to remove the remaining bearings; noting that the No. 1 bearina needs to be removed from the rear of the block to allow for proper centering of the tool. Fig. 103 Use a micrometer when checking the camshaft lift with the shaft out of the engine DIMENSION A DIMENSION THE CAM LOBE A Fig. 104 Measure the camshaft lobe at these two points with the micrometer Fig. 105 Use a dial indicator when checking the camshaft lift with the shaft in the engine ENGINE MECHANICAL-GM V6 AND V8 ENGINES 5-33 IFig. 106 Make sure you don't cant the camshaft during removal or installation. Note the two 4 in. bolts screwed into the end of the shaft (V6 shown) Fig. 107 Camshaft bearing removal tool used on 1986-96 engines To install: 22. If you removed the bearings: 1986-96 engines: 23. lnstall the installer tool on the driver handle and then drive the front and rear into the block from the outside toward the center the following Note oil hole alignment). 24. Remove the handle from the pilot tool and install the inner bearing on the tool. 25. Position the tool and bearing to the rear of the inner bore. Install the screw shaft, with the remover, through the block and onto the pilot-from the front of the cylinder block. 26. Align the oil hole in the bearing with the oil gallery hole and then snug the puller nut up against the adaptor. Using two wrenches again, hold the screw shaft with one while turning the puller with the other until the bearing is in position. The oil will not be visible during installation. To make installation easier, align the holes in the bearing with those in the block and then mark the opposite side of the bearinglblock. To make it easier for you, the bearing should have the holes on equal sides of the 6 o'clock position; Nos. 2,3 and 4 bearing holes should be positioned at the 5 o'clock position (toward the left side of engine) and even with the bottom of the cylinder bore; No. 5's oil hole should be at the 12 o'clock position. 27. Repeat the last step for the remaining bearings. 28. Coat a new rear welch plug with sealant and install it so that it is flush with the surface of the cylinder block, or no more than 1132 in. deep when measured from the outer edge of its recess. 1997-98 engines: 29. Bearing installation on these engines is essentially the reverse of removal. Take note of the following though: lnstall the front and rear bearings first, from the outside toward the inside. Bearing bore sizes may vary, be sure you have the correct bearings when replacing them. sure that the oil holes in the bearing align with the holes in the block, during and after installation. Coat a new rear welch plug with sealant and install it so that it is flush with the surface of the cylinder block, or no more than 1132 in. deep when measured from the outer edge of its recess. On all engines now: Inspect the camshaft as detailed previously. 31. Coat the camshaft journals with engine oil. Coat the camshaft lobes and distributor drive gear teeth with GM Engine oil supplement or Molykote (in a pinch, just use engine oil). 32. Reinstall the long bolts and carefully insert the shaft into the cylinder block and slide it all the way in. Be very careful not to damage the bearings. 33. Remove the installation bolts and install the thrust (if equipped) and tighten the bolts to 106 inch Ibs. (12 on 1986-96 engines and all V8 engines, or 124 inch Ibs. (14 Nm) on 1997-98 engines. 34. lnstall the fuel pump and push rod on engines so equipped. 35. lnstall the drive aears, chain and front cover. Drop the lifters into original bores so that they are aligned with the matchmarks and then install the restrictors. lnstall the push rods. lnstall the intake manifold. 38. lnstall the rocker assemblies and the cylinder head covers. REMOVAL INSTALLATION CULT See Figures 108,109,110,111,112 and 113 Drain the water from the cylinder block and manifold. 2. Remove the fuel line support brackets. Disconnect the fuel line at the body and fuel pump, plug the fitting holes and remove the line. 3. Remove the cylinder head cover and rocker assemblies as detailed previously in this section. 4. Remove the intake and exhaust manifolds as previously detailed; you can leave the carburetorlthrottle body attached to the intake manifold if you like. 5. If you intend to remove the valve lifters, now is the time to do it. Either way, make sure that you cover the valley of the cylinder block carefully with plenty of rags to prevent dirt from entering any of the passages or settling on any components. 6. Tag and disconnect the spark plug wires at the plugs; move them out of the way. Although not necessary, it's a good idea to remove the plugs themselves also; plug the holes if you do. 7. Remove or relocate any components or connections that may interfere with the removal of an individual cylinder head. 8. Loosen the cylinder head bolts in the reverse order of the illustrated tightening sequence and then carefully lift the head off the block. You may need to persuade it with a rubber mallet-be careful! Set the head down carefully on two support blocks; do not sit it on cement. Its always a good idea to keep a record of which bolts came from which holes. It may sound silly, but on many engines they are different sizes and you wouldn't be the first person to break off a long bolt while tightening it in a short hole. Spend the extra few seconds and do this! To install: 9. Carefully, and thoroughly, remove all residual head gasket material from the cylinder head and block mating surfaces with a scraper or putty knife. Check that the mating surfaces are free of any nicks or cracks. Make sure there is no dirt or old gasket material in any of the bolt holes. Refer to the Engine Rebuilding section found for complete details on inspection and refurbishing procedures. 5-34 ENGINE MECHANICAL-GM V6 AND V8 ENGINES I A-Front I Fig. 108 Cylinder head tightening sequence--1986-96 V6 engines Fig. Cylinder head tightening seauence1997- 98 V6 enaines Fig. Cylinder head tightening V8 engines Fig. 111 Cylinder head tightening sequence7.4118.21 V8 engines I Fig. 112 Cylinder head tightening sequence8.1 L V8 engines -Cylinder head 2-Head bolts Fig. 113 Many engines have three different size bolts 10. Position a new gasket over the cylinder block dowel pins. Do not use any sealer as the gasket is coated with a which will provide the proper sealing effect once the engine gets to normal operating temperature the first time. DO NOT use automotive-type steel gaskets. Make sure the word UP is facing, you guessed it, up, if noted on your gasket. Position the cylinder head over the dowels in the block. Coat the threads of the head bolts with Gasket Sealing compound and install them finger tight. It never hurts to use new bolts, although it's not necessary. 12. Tighten the bolts, a little at a time, in the sequence illustrated, until the proper tightening torque is achieved. 1986-97 V6 and V8 engines (except the 1997 the first step should be 25 ft. Ibs. (34 Nm), the second step should be 45 ft. Ibs. (61 Nm), while the last step should be to 65 ft. Ibs. (88 Nm). 1998 engines: tighten all the bolts, in sequence, to 22 ft. Ibs. (30 Nm). Next, turn the short bolts 7, 3, 2, 6 10) an additional 55"; the medium bolts 13) an additional and the long bolts 4, 8, 5 9) an additional Obviously you will need a meter for these last passes. 1997 and all 1998 V8 engines: tighten all the bolts, in sequence, to 22 ft. Ibs. (30 Nm). Next, turn the short bolts 4, 7, 8, 11, 12, 15 16) an additional the medium bolts 17) an additional and the long bolts 2, 5, 6, 9, 10 13) an additional Obviously you will need a meter for these last passes. V8 engines: the first step should be 35 ft. Ibs. (47 Nm), the second step should be 65 ft. (88 Nm), while the last step should be to 80 ft. (108 Nm) on 1988-91 engines or 85 ft. Ibs. (115 Nm) on 1992-98 engines. 13. Install the rocker assemblies and the cylinder head cover. Don't forget the baffle plate and on engines so equipped. 14. Install the manifolds and connect the fuel line. Don't forget to remove the fitting plugs. Install the spark plugs if they were removed and then connect the plug wires. 16. Install or connect any other components removed to facilitate getting the head off. 17. Add connect the battery and check the oil. Start the engine and run it for a while to ensure that everything is operating properly. Keep an eye on the temperature gauge. 18. It never hurts to re-tighten the cylinder head bolts again after 20 hours of operation. REMOVAL INSTALLATION See Figure 114 Disconnect the battery cables and then drain all the block and manifolds. 2. Drain all waterlcoolant from the cylinder block. 3. Loosen, but do not remove, the pump pulley mounting bolts. 4. Loosen the power steering pump and alternator bracket bolts and swivel them in until you are able to remove the Different engines may have different systems, follow the belt back and loosen the appropriate components. 5. Now you can remove the pump pulley bolts along with the lock washers and clamping ring. Pull off the pulley. 6. Disconnect the water hoses at the pump. 7. Remove the mountinq bolts and lift the pump off of the block. CYLINDER Figure 114 Removing the water circulating pump ENGINE MECHANICAL-GM V6 AND V8 ENGINES 5-35 To install: 10. Reconnect the water hoses and tighten the hose clamps securely. 8. Carefully scrape any old gasket material off both mounting surfaces. 11. Position the pump pulley and clamping ring on the boss. Screw the Inspect the pump for blockage, cracks or any other damage. Inspect the mounting bolts and lock washers in and tighten them securely. impeller for cracks. Replace either if necessary. 12. Install the drive and adjust them as detailed previously. Start with sealant and position on the the engine and check the system for leaks. cylinder block. Coat the threads of the pump mounting bolts with sealant, install the pump and tighten the bolts to: 30 ft. Ibs. (41 Nm) on 9. Coat both sides of a new V6 and V8 engines 35 ft. (47 on V8 engines. Damper Reinforcing Strip 115 Exploded view of the cylinder block, all years similar-V6 engines Fig. 116 Exploded view of the cylinder block, all years similar-V8 engines Rocker Rocker ArmNut Hoist Bracket Spring Cylinder Head , Exhaust Valve Gasket Fig. 118 Exploded view of the cylinder head, all years V8 engines ENGINE MECHANICAL-GM V6 AND V8 ENGINES 5-37 Distributor ,Bolt Clamp Throttle Distributor Gasket Cable Cover Fig. 120 Exploded view of the intake manifold, all years similar-V6 engines, V8 and Pad Arrestor Fig. 121 Exploded view of the upper intake manifold-1996-98 MPI V8 engines carbureted V8 enaines verv similar ENGINE MECHANICAL-GM V6 AND V8 ENGINES 5-39 Distributor down Fig. 122 Exploded view of the lower intake manifold-1996-98 MPI Sender engines TORQUE SPECIFICATIONS V6TORQUE SPECIFICATIONS -V6 Component inch Ibs. Component Ibs. inch Ibs. Nm Exhaust Pipe To transom Oil Pump Cover bolts 1986-90 14-16 1991-98 20-25 27-34 Mounting Bolts 1986-91 28-36 38-39 Oil Pressure Sender 10-14 1992-98 32-40 Sender 14-19 Coupler Nut Oil Seal Retainer Flywheel Bellhousing 135 Cover 60-84 7-9 Oil Withdrawal Tube (flare) 15-1 8 20-24 ft. Nm 43-54 40-45 54-61 65 90 Adaptor 14-19 10-14 15.3 Stud Power Steering Pump Bracket 26-30 35-41 1992-98 15-20 20-27 1986-91 20-25 27-34 13-15 18-20 Timing Sensor 48-64 5-7 Lines Front Cover 80 9 I. . Harmonic Balancer 1986-90 60 81 1991-96 70 95 I Ignition Coil Clamp 7-10 0.8-1.13 Intake Manifold 1986-95 30 41 48.. 1997-08 11 15 Main Bearing Cap 1986-91 70 95 1992-96 Outer on #2, #3, 70 95 All others 80 77 105 Manifolds Exhaust 18-22 24-30 Large fitting 15-17 20-23 Small fitting 10-12 14-16 Raw Water Pump Bracket 30 41 Rocker Arm Nut 1997-98 20 27 Stud 35 47 Spark Plugs 22 30 Timing Chain Cover 1986-96 80 9 13 Valve Cover Valve Lifler Guide Retainer 12 Water Pump (circulating pump) 30 . 41 Water Temperature Sender 18-22 24-30 1991-98 20-26 27-35 1997and later: New -22fl. (30 Nm); used - fl. Ibs.(20 Nm) lntake 1986-95 30 41 1996 35 48 1997-08 11 Oil Filter Adaptor (Remote) To block 20-25 27-34 Oil Filter Bypass Valve 20 , -27 Oil Pan 1986-96 20bolts 6-7.5 8-1 0 12-15 16-20 1997-98 Nuts 17 23 18 25 Dipstick Tube Fitting 15-1 8 20-24 Drain Retainer 15-1 8 20-24 TORQUE SPECIFICATIONS -V8 Component ft. lbs. Ibs. Nm Camshaft Sprocket 20 22 1992 5 7 LE 11 21 28 Retainer Bolt 1986-97 124 14 1998 12 Rod Cap 1992-97 45 60 1998 deg 27 Coolant Temp Sender 15 20 Crankshaft Main Bearing Cap 70 95 I Outer on 3, 4 70 95 All others 80 .. Oil Seal Retainer 135 15.3 Pulley Bolt 43 58 Head Bolts 1986-97 Step 1 25 34 7 AS Step 3 65 88 1998 Core Plug 15 20 Cover 45 5 Tube 15-18 20-24 Cap Bolt 21 2.4 Clamp Bolt 20 27 Mounts Front To engine 32-40 43-54 nut 100-120 136-163 Nut 60-75 81-102 , Exhaust Elbow To Manifold 1986-93 10-12 14-16 1994-98 12-18 16-24 Exhaust 20-26 27-35 Exhaust To transom 1986-90 14-16 1991-98 20-25 27-34 Flame Arrestor Cover 3 4-4 5 studs 65-80 7-9 Flywheel 1986-91 28-36 38-49 A7 44 nut And5. ,.. . .. Coupler stud 20-25 27-34 1992-98 15-20 20-27 Front Cover 80 . 9. 1997 use 1998 specifications bolt: 74 ft. Ibs. (100 Outboard bolt (4 bolt caps) 67 Ibs (90 Nm) pass: 22 ft (30 Nm); 2nd pass: bolt 55 deg., medium bolt 65 deg.. long bolt 75 deg 1991 350 and 1992 5.7 LE: 65 inch (7 Nm) TORQUE SPECIFICATIONS -V8 Component ft. lbs. lnch lbs. Nm Balancer 1986-90 60 81 70 95 74 Coil Clamp 7-10 Intake Manifold 30 41 1992-97 Outer on 3, 4 70 95 Exhaust 20-26 27-35 Intake 30 41 1998 Pan 114x20 bolts 6-7.5 8-10 5116x18 12-15 16-20 All others 106 12 Dipstick Tube Fitting 15-18 20-24 Drain Plug 18 25 Retainer 15-18 20-24 Oil Pump Cover bolts 6-9 8-12 1998 106 12 bolts 65 90 Oil Pressure Sender Sender 14-19 Adaptor -14-19 Oil Pressure Gauge Sensor 11 15 Oil Seal Retainer 135 15.3 Withdrawal Tube (flare) 15-18 20-24 Bracket Bolt 26-30 35-41 Studlnut 13-15 18-20 Large fitting 15-17 20-23 Small fitting 10-12 14-16 Raw Water Pump Bracket 30 41 Rocker Arm Nut 40 54 35 47 Spark Plugs 22 30 Chain Cover 80 9 1998 12 Valve Cover 45 5 1997 90 10 1998-03 106 12 Valve Retainer 18 25 Pump 30 41 Water Temperature Sender 18-22 24-30 Windage Tray Nut 29 40 1997 use 1998 Inboard bolt. 74 ft. Ibs (100 Nm); Outboard bolt (4 bolt caps): 67 ft. (90 Nm) 1991 350 and 1992 5.7 LE: 65 inch Ibs. (7 Nm) pass: 27 inch Ibs (3 2nd pass: Ibs. (12 Nm); 3rd pass: 11 ft. Ibs. (15 Nm) 1998: New 22 ft. (30 Nm); used 11 ft. Ibs. (15 Nm) TORQUE SPECIFICATIONS Component Camshaft Sprocket ft. 20 25 inch lbs. Nm 27 34 Connecting rod cap 1992-96 A 48 711 65 Coolant Temp. Sensor Crankshaft Main Bearing Cap Rear 15 70 20 95 . 100 135 149 . . Cylinder Head 1988-91 Step 35 47 Step 2 65 88 Step 3 80 108 1992-98 Step 1 35 47 7 Timing sensor 48-64 5-7 Front Cover 1992-97 96 10.8 TORQUE SPECIFICATIONS - Component ft. inch lbs. Nm Fuel Rail Bolt 89 Harmonic Balancer Exc. 1998 Gi 85 115 1998 149 90 122 Intake Manifold 300 410 Main Bearing Cap 1988-91 Rear 70 95 .. . . 1992-98 7 4L 135 8 2L 110 149 Exhaust Nut 20-26 27-35 Bolt 24-28 33-38 Intake 7 4L 300 410 71 A7 MAP Sensor 18 25 Oil Filter Adaptor (Remote) 20-25 27-34 Oil Filter Bypass Valve 20 27 Oil Pan All exc. 1998 To Block 160 18 To Front Cover 70 8 To Block 200 22.5 To Front Cover 120 14 1998 18 25 Dipstick tube fitting 15-18 20-24 Oil Pump Cover Bolts Exc. 1998 80 9 1998 106 12 . Mounting Bolts 65 90 Power Steering Pump Bracket Bolt 26-30 35-41 13-15 18-20 Lines Large fitting 15-17 20-23 Small fitting 14-16 Rocker Arm Bolt 1998 Gi 40 54 1998 45 61 Spark Plugs 22 30 Timing Chain Cover Block bolts 6 8 Pan bolts 8 1992-97 96 10.8 120 13.6 1998 106 12 120 13.6 Valve Cover 1988-95 Nuts 115 13 . . 1996-97 -60-90 7-10 1998 (exc. Gi) Nuts 115 13 Stud 60-90 7-10 7 77 7 Lower only, upper 10 ft Ibs (14 1998: New 22 ft. Ibs. (30 Nm); used 15 ft. ibs. (20 Nrn) Unless otherwise noted ENGINE SPECIFICATIONS Standard Component (in.) Rings Groove Clearance Production 198696 0.0012-0.0032 0.0305-0.0813 Compression 0.020 06 Service Limit 198596 M.OO1 0.004 Max Max Production 020 0.254-0.508 2nd: 0.0100.025 Limit 0.035 Max 0.89 Max Piston Rings Groove clearance Production 0.051-0.177 Oil Service Limit M.025 MAX 0.203MAX Production 198696 1997-03 0.0150.050 Service Limn 0.065 1.651 0.927 23.545 Clearance Production Service 0.001 Max 0.025 Max fit system Face Angle 45 deg. 45 deg. Lash 1 turn down 1 turn down Net Lash Net Lash Lifl intake 0.414 51 Exhaust 0.428 10.87 Liier Hydraulic Hydraulic Rocker Arm Ratio Seat Angle 46 deg. 46 deg. Seat Width Intake 198696 0.0312-0.0625 1.0161.651 Exhaust 1986-96 0.065-0.098 Spring Free Length 2.03 51.6 Spring installed Ht. 710 42.92-43.43 Spring Pressure Open 198696 Ibs. 1 25 N 31.75 Ibs. 1.27 N Q 32.25 Closed 76-84 1.70 N 43.16 Clear. 0.0254-0.0686 Limit Intake 0.001 Max 0.025 Max Exhaust Max 0.51 Max Unless otherwise noted I ENGINE -V8 Standard Metric ENGINE SPECIFICATIONS - Standard Metric Component (in.) Clearance Production 1986-97 0.0007-0.0017 0.0178-0.0431 1998 0.0007-0.0021 0.018-0.053 Service Limit Max 0.076 Max Piston Rings -Groove Clearance Production 2-0.0032 0.031-0.081 Compression Service Limit ffi.025 Production Too: , . . . Piston Rings -Groove clearance Production 0.002-0.007 0.051-0.177 Oil Service Limit Production 0.015-0.055 0.381-1.397 1998 0.01 0-0.030 0.25-0.76 Service Limit 1986-97 ffi.254 , . . Piston Diameter 1998 0.9270-0.09271 Clearance Produchon 1986-97 0.006-0.009 1998 0.010-0.020 I Hydraulo Rocker Arm Raho 1 50 1 1 50 1 Seat Angle 46 deg. 46 deg. Seat Width Intake 1986-97 1998 0.045-0.065 1.14-1.65 Exhaust 0.1587-0.2381 1998 0.065-0.098 Spring Free Length 2.03 51.6 Spring Ht. 1998 42.92-43.43 Spring Pressure Open 194-206Ibs. 1.25 N 31.75 1998 Ibs. 1.27 832-903 N 32.25 Closed 76-84 1.70 338374 N 43.16 Stem-to-Guide Clear. Production 0.0010-0.0027 0.0254-0.0686 Limit intake Exhaust Unless otherwise noted 1997 Use 1998 Unless otherwise noted 1997 Use 1998 specifications ENGINE MECHANICAL-GM V6 AND V8 ENGINES 5-45 ENGINE V8 Standard Metric Component (in.) Camshaft End Play 0.004-0.01 2 0.10-0.31 Journal Diameter All Exc. 1998 49.484-49.51 0 1998 49.471-49.522 Journal Out-of-Round 0.001 Max 0.025 Max Lobe 0.002) ke 1998 0.282 7. 163 All others 0.234 594 Exhaust 1998 0.284 7.21 4 All others 0.253 6.43 0.51 12.95 0.002 Max 0.051 Max Connecting Rod Bearing Clearance Production 0.0009-0.0025 0.0229-0.0635 1992-98 0.001 1-0.0029 0.0279-0.0737 Service Limit 1998 0.001 1-0.0039 0.028-0.099 All others 0.0035 Max 0.076 Max Clearance 0.01 5-0.021 1 992-98 3-0.0230 0.033-0.584 Journal Diameter 2.1 988-2.1 996 55.85-55.87 2.2 55.88 Taper Production 0.0005 Max 0.01 27 Max Service Limit 0.001 Max 0.02 Max Out-of-round Production 0.0005 Max 0.0127 Max Service Limit 0.001 Max 0.0254 Max Crankshaft Crankshaft End Play 1998 0.005-0.01 1 0.127-0.279 All others 0.006-0.01 0 0.1 52-0.254 Bearing Clearance 1988-91 Production 2, 3,4 0.001 3-0.0025 0.033-0.064 0.0024-0.0040 0.061-0.102 Service Limit 0.002 Max 0.051 Max 3, 4, 5 0.0035 Max 0.089 Max 1992-98 Production 0.0017-0.0030 0.043-0.076 0.0025-0.0040 0.064-0.097 Service Limit 2, 3, 4 0.001 0-0.0030 0.025-0.076 0.064-0.102 1998 Production 0.001 7-0 0030 0.043-0.076 3, 4 0.001 1-0.0024 0.028-0.061 0.0025-0.0038 0.063-0.096 Service Limit 2, 3, 4 0.001 0-0.0030 0.025-0.076 0.0025-0.0040 0.064-0.102 Journal Diameter 2.7482-2.7489 69.804-69.822 Taper Production 1998 0.0004 Max 0.010 Max All others 0.0002 Max 0.005 Max Service Limit 0.001 Max 0.025 Max Out-of-round Production 1998 0.0004 Max 0.010 Max All others 0.0002 Max 0.005 Max Service Limit 0.001 Max 0.025 Max Cylinder Bore Diameter 4.2500-4.2507 107.95-1 07.97 11 3.42-1 13.44 Out-of-round 0.002 Max 0.05 Max Taper 0.001 Max 0.025 Max Unless otherwise noted 5-46 ENGINE MECHANICAL-GM V6 AND V8 ENGINES ENGINE V8 Component (in.) (mm) Cylinder Head Gasket surface flatness 0.003 Max 0.08 Max Piston Clearance Production 1988-91 0.0008-0.0028 0.020-0.071 1992-98 0.003-0.004 0.076-0.102 1998 Gi 0.001 8-0.0030 0.046-0.076 8.2 0.004-0.005 0.102-0.127 Service Limit 0.005 Max 0.127 Piston Rings Groove Clearance Production 0.001 0.043-0.081 Compression 1992-98 0.001 0.030-0.074 Service Limit 0.001 0.031-0.099 All others Top 0.01 0-0.01 8 0.254-0.457 2nd 0.01 6-0.024 0.406-0.609 Service Limit 1998 Gi Production 0.01 0-0.020 Unless otherwise noted CAMSHAFT CHECKING REMOVAL INSTALLATION CYLINDER HEAD REMOVAL INSTALLATION CYLINDER HEAD (VALVE) COVER REMOVAL INSTALLATION ENGINE MINIMUM ENGINE HEIGHT ENGINE ALIGNMENT MODEL DESIGNATIONS REMOVAL INSTALLATION ENGINE AND FLYWHEEL REMOVAL INSTALLATION ENGINE CIRCULATING PUMP REMOVAL INSTALLATION ENGINE IDENTIFICATION ENGINE MECHANICAL CAMSHAFT CYLINDER HEAD CYLINDER HEAD (VALVE) COVER ENGINE ENGINE CIRCULATING PUMP ENGINE AND FLYWHEEL ENGINE IDENTIFICATION EXHAUST ELBOW EXHAUST HOSES 6-21 EXHAUST ELBOW 6-21 REMOVAL INSTALLATION ... 6-22 EXHAUST HOSES (BELLOWS) . . 6-22 REMOVAL INSTALLATION ... 6-22 EXHAUST MANIFOLD ......... 6-7 REMOVAL INSTALLATION ... 6-7 EXHAUST VALVE (FLAPPER) ... 6-3 REPLACEMENT EXPLODED VIEWS 6-4 CYLINDER BLOCK 6-5 CYLINDER HEAD INTAKE MANIFOLD .......... 6-3 FRONT COVER AND OIL SEAL . . REMOVAL INSTALLATION ... 6-16 FRONT ENGINE MOUNTS 6-16 REMOVAL INSTALLATION ... 6-23 GENERAL INFORMATION ...... 6-23 HYDRAULIC VALVE LIFTER .... REMOVAL INSTALLATION ... 6-2 INTAKE MANIFOLD 6-21 REMOVAL INSTALLATION ... 6-22 INTERMEDIATE EXHAUST PlPE . 6-7 REMOVAL INSTALLATION ... LOWER EXHAUST PlPE (Y-PIPE) 6-23 REMOVAL INSTALLATION ... OIL PAN .................... 6-16 REMOVAL INSTALLATION ... 6-2 OIL PUMP 6-13 REMOVAL INSTALLATION ... 6-13 REAR ENGINE MOUNTS REMOVAL INSTALLATION ... FRONT COVER AND SEAL FRONT ENGINE MOUNTS GENERAL INFORMATION HYDRAULIC VALVE LIFTER INTAKE MANIFOLD INTERMEDIATE EXHAUST LOWER EXHAUST PIPE (Y-PIPE) PUMP REAR ENGINE MOUNTS REAR SEAL ROCKER ARMS AND PUSH RODS TIMING CHAIN AND SPROCKETS VIBRATION DAMPER. PULLEY AND HUB 6-20 REAR OIL SEAL 6-6 REMOVAL INSTALLATION ... 6-2 ROCKER ARMS AND PUSH RODS 6-10 REMOVAL INSTALLATION ... 6-10 VALVE CLEARANCE CHECK ... 6-13 SPECIFICATIONS 6-13 ENGINE. .......... 6-16 ENGINE. 6-16 TORQUE .................. 6-6 TIMING CHAIN AND SPROCKETS 6-18 REMOVAL INSTALLATION ... 6-7 VALVE CLEARANCE .......... 6-20 CHECK VIBRATION DAMPER. PULLEY 6-19 AND HUB REMOVAL INSTALLATION ... 6-2 ENGINE MECHANICAL-FORD V8 ENGINES NEVER, NEVER attempt to use standard automotive parts when replacing anything on your engine. Due to the uniqueness of the environment in which they are operated in, and the levels at which they are operated at, marine engines require different versions of the same part; even if they look the same. Stock and most aftermarket automotive parts will not hold up for prolonged periods of time under such conditions. Automotive parts may appear identical to marine parts, but be assured, OMC marine parts are specially manufactured to meet OMC marine specifications. Most marine items are super heavy-duty units or are made from special metal alloy to combat against a corrosive saltwater atmosphere. OMC marine electrical and ignition parts are extremely critical. In the United States, all electrical and ignition parts manufactured for marine application must conform to stringent Coast Guard requirements for spark or flame suppression. A spark from a non-marine cranking motor solenoid could ignite an explosive atmosphere of gasoline vapors in an enclosed engine compartment. V8 ENGINES The OMC 302 cubic inch and 351 cubic inch and 460 cubic inch displacement V8 engines are manufactured by Ford Motor Company. These engines are used in the following configurations: 5.0 (214 bbl) 5.0 EFI (EFI) (EFI) (2 bbl) 5.0 HO (2 bbl) 5.8 (4 bbl) 5.8 EFI (EFI) (EFI) (4 bbl) (EFI) 5.8 HO (EFI) 5.8 LE (4 bbl) 7.5 (4 bbl) 351 (4 bbl) 351 EFI (EFI) 460 (4 bbl) Cylinder numbering and firing order is identified in the illustrations at the end of the Maintenance Section. ENGINE See Figures 1 and 2 The engine serial numbers are the manufacturer's key to engine changes. These alpha-numeric codes identify the year of manufacture, the horsepower rating and various differences. If any correspondence or parts are required, the engine serial number must be used for proper identification. Remember that the serial number establishes the year in which the engine was produced, which is often not the year of first installation. The engine specifications decal contains information such as the model number or code, the serial number (a unique sequential identifier given ONLY to that one engine) as well as other useful information. An engine specifications decal can generally be found on top of the flame arrestor (early models), or on the inner side of the rocker arm cover, usually near the line (port side on most models); further, on fuel injected engine you can find it on the side of the TFI module bracket all pertinent serial number information can be found here-engine and drive designations, serial numbers and model numbers. Unfortunately this decal is not always legible on older boats and it's also quite difficult to find, so please refer to the following procedures for each individuals unit's serial number location. Serial numbers tags are frequently difficult to see when the engine is installed in the boat; a mirror can be a handy way to read all the numbers. The engine seriallmodel number is usually stamped on the port rear side of the engine where it attaches to the bell housing; although on most later models it may instead be a metal plate attached in the same location. If your engine has a stamped number it will simply be the serial number; if you have a plate (and you should), it will always show a Product number, a number and then the actual Serial number. The first two characters identify the engine size in liters (L); 50 represents the 58 represents the and so forth. The third character identifies the fuel delivery system; 2 designates a 2 bbl carburetor, 4 is a 4 bbl carburetor, and F is a fuel injected engine. The fourth character designates a major engine or horsepower change-it doesn't let you know what the change was, just that there was some sort of change. A means it is the first model released, B would be the second, and so forth The fifth character designates what type of steering system was used; M would be manual steering and P would be power steering. Now here's where it gets interesting; on 1986-87 engines and 1994-98 engines, the sixth, seventh and eighth characters designate the model year. The sixth and seventh actually show the model year, while the eighth is a random model year version code. KWB and WXS represent 1986; and ARJ, ARF, FTC, SRC or SRY show 1987. MDA is 1994, HUB is 1995, NCA is 1996, LKD is 1997 and BYC is 1998. On 1988-93 engines, the sixth character designates the direction of propeller rotation. is right hand, L is left hand and E is either. Also on 1988-93 engines, the seventh, eighth and ninth characters designate the model year. The seventh and eighth actually show the model while the ninth is a random model year version code. GDE or GDP is 1988, MED or MEF is 1989, PWC, or PWS is 1990, RGD or RGF is 1991, AMH or AMK is 1992 and JVB or JVN is 1993. Fig. 1 Engine serial number sticker Fig. 2 On fuel injected engines, look on the TFI module bracket ENGINE MECHANICAL-FORD V8 ENGINES 6-3 Any remaining characters are proprietary. So in example, a Model 2. Remove the stern drive unit as detailed in the Drive Systems section. number on the ID plate that reads would designate a 1987 engine with a 4 bbl carburetor and power steering, first model released. A number reading designate a 1993 engine with fuel injection, power steering and a right hand propeller, first release; get the picture? Engine Model Designations All engines covered here utilize unique identifiers assigned by OMC; surnames if you etc. Obviously the first two characters designate the engine size in litres (L). The second letter, a G or and F designate the engine manufacturer; General Motors (G) or Ford (F). The third through fifth letters can be found in different combinations, but the individual letter designates the same thing regardless of position. L designates limited output. and X designate superior output-a will always have a lesser horsepower rating than a in a given model year. An designates that the engine is fuel injected, if there is no i then you know the engine uses a carburetor. REMOVAL & INSTALLATION CULT See Figures Prior to removing the engine from your vessel, it is imperative to measure the engine height as detailed in the Determining Minimum Engine Height section. DONOT remove the engine until you have completed this procedure! Check the clearance between the front of the engine and the inside edge of the engine compartment bulkhead. If clearance is less than 6 in. you will need to remove the stern drive unit because there won't be enough room to disengage the driveshaft from the engine coupler. More than 6 in. will provide enough working room to get the engine out without removing the drive, BUT, we recommend removing the drive anyway. If you intend on doing anything to the mounts or stringers, you will need to re-align the engine as detailed in the Engine Alignment section-which requires removing the drive, so remove the drive! 3. Open or remove the engine hatch cover. 4. Disconnect the battery cables (negative first) at the battery and then disconnect them from the engine block and starter. Make sure that all switches and systems are OFF before disconnecting the batterv cables. 5. Disconnect the two power steering hydraulic lines at the steering cylinder (models Carefully plug them and then tie them off somewhere on the engine, making sure that they are higher then the pump to minimize any leakage. Disconnect the fuel inlet line at the fuel pump or filter (whichever comes first on your particular engine) and quickly plug it and the inlet-a clean golf tee and some tape works well in this situation. Make sure you have rags handy, as there will be some spillage. 7. Tag and disconnect the two-wire trimitilt connector. 8. Pop the two-wire sender connector out of the retainer and then disconnect it. You may have to cut the plastic tie securing the cable in order to move it out of the way. 9. Locate the large rubber coated instrument cable connector (should be on the starboard side), loosen the hose clamp and then disconnect it from the bracket. Move it away from the engine and secure it. On early models, you will also need to unplug the three-wire instrument cable connector just above it. Take note of you throttle arm attachment stud-is it a close" or a "pull-to-close"? What hole is it on?? Remove the cotter pin and washer from the throttle arm. Loosen the anchor block retaining nut and then spin the retainer away from the cable trunnion. Remove the throttle cable from the arm and anchor bracket. Be sure to mark the position of the holes that the anchor block was attached to. 11. Loosen the hose clamps and disconnect the exhaust hose bellows from intermediate or exhaust pipe. You may want to spray some WD-40 around the lip of the hose where it connects to the elbow, grasp it with both hands and wiggle it back and forth while pulling down on it. Slide it down over the lower pipe. 12. Drain the cooling system as detailed in the Maintenance section. I Fig. 3 Disconnect the power steering lines at the cylinder Thottle Arm I Jam Anchor Bracket Lock Nut Cable Block Fig. 6 Details of the throttle cable assembly-Fi and engines Fig. 4 Disconnect the instrument cable connector Fig. 7 Locate the engine lifting brackets and then connect and engine hoist Throttle Arm Anchor Block Fig. 5 Details of the throttle cable assembly-FL engines Boss Fig. 8 Details of the throttle cable and trunnion 6-4 ENGINE MECHANICAL-FORD V8 ENGINES Fig. 9 Attach the anchor block assembly to the bracket 13. Loosen the hose clamp on the water supply hose at the transom bracket and carefully slide it off the water tube. Attach the hose to the engine. 14. Disconnect the shift cables and position them out of the way. 15. Tag and disconnect any remaining lines, wires or hoses at the engine. 16. Attach a suitable engine hoist to the lifting eyes and take up any line slack until it is just taught. The engine hoist should have a capacity of at least 1500 Ibs. (680 17. Locate the rear engine mounts and remove both lock nuts and flat washers. 18. Locate the front engine mounts and remove the two (per mount) lag bolts. 19. If vou listened to us at the beainnina of the the drive unit should If so, slowly lift the engine. Try not to hit the power steering control valve, or any other accessories, while removing it from the engine compartment. If you didn't listen to us, and you had sufficient clearance in the engine compartment, the drive unit is probably still installed. Raise the hoist slightly the weight is removed from the mounts and then carefully pull the engine forward until the driveshaft disengages from the coupler, now raise the engine out of the compartment. To Install: 20. Apply Engine Coupler grease to the splines of the coupler. 21. Slowly lower the engine into the compartment. If the drive unit was not removed, AND the crankshaft has not been rotated, insert the driveshaft into the coupler as you push the engine backwards until they engage completely and then lower the engine into position over the rear mounts until the front mounts just touch the stringers. If the shaft and coupler will not align completely, turn the crankshaft or driveshaft slightly until they mate correctly. If the drive was removed, or the mounts were disturbed in any way, lower the engine into position over the rear mounts until the front mount just touches the stringer. 22. Install the two flat washers into the recess in the engine bracket side of the rear mounts and then install the two lock nuts. Tighten them to 28-30 ft. (38-40 Nm). Never use an wrench or driver to the locknuts. 23. lnstall the lag bolts into their holes on the front mounts and tighten each bolt securely. 24. If the drive was removed, the mounts were disturbed, or the driveshaftlcoupler didn't mate correctly, perform the engine alignment procedure detailed in this section. We think it's a good idea to do this regardless! 25. Reconnect the exhaust bellows by sliding it up and over the pipe, position the clamps between the ribs in the hose and then tighten the clamps securely. Make sure you don't position the clamps into the expanding area. 26. Reconnect the water inlet hose. Lubricate the inside of the hose and wiggle it onto the inlet tube. Slide the clamp over the ridge and tighten it securely. This sounds like an easy step, but it is very important-if the hose, particularly the underside, is not installed correctly the hose itself may collapse or come off. Either scenario will cause severe damage to your engine, so make sure you do this correctly! 27. Carefully, and quickly, remove the tape and plugs so you can connect the power steering lines. Tighten the large fitting to 15-17 ft. Ibs. (20-23 Nm) and the small fitting to 10-12 Ibs. (14-16 Nm). Don't forget to check the fluid level and bleed the system when you are finished with the installation. 28. Reconnect the connector so the two halves lock together. 29. Reconnect the trim position sender leads, the instrument cable, the engine ground wire, the battery cables and all other wires, lines of hoses that were disconnected during removal. Make sure you swab a light coat of grease around the fitting for the large cable plug. Always make certain that all switches and systems are turned OFF before reconnecting the battery cables. Make sure all cables, wires and hoses are routed correctly before initially starting the engine. 30. Unplug the fuel line and fitting and reconnect them. Remember to check for leaks as soon as you start the engine. 31. Install and adjust the throttle cable. For complete details, please refer to the Fuel System section): a. Remember we asked you to determine if you had a "push-to-close" or "pull-to-open" throttle cable (the throttle arm stud)? Position the remote control handle in Neutral-the propeller should rotate freely. b. Turn the propeller shaft and the shifter into the forward gear detent position and then move the shifter back toward the Neutral position halfway. c. Position the trunnion over the groove in the throttle cable so the internal bosses align and then snap it into the groove until it is fully seated. d. lnstall the into the anchor block so the open side of the trunnion is against the block. Position the assembly onto the bracket over the original holes (they should be the lower two of the four holes) and then install the retaining bolt and nut. When the nut is securely against the back of the bracket, tighten the bolt securely. e, lnstall the connector onto the throttle cable and then pull the connector until all end play is removed from the cable. Turn it sideways until the hole is in alignment with the correct stud on the throttle arm. Slide it over the stud and install the washer and a new cotter pin. Make sure the cable is on the same stud that it was removed from. Tighten the jam nut against the connector The throttle arm connector nut must be installed on the cable with a minimum of 9 turns-meaning that at least 114 in. of thread should be showing between the end of the cable and the edge of the nut. 32. Install and adjust the shift cables. Please refer to the Drive Systems section for further details. 33. Check and refill all fluids. Start the engine and check for any fuel or coolant leaks. Go have fun! DETERMINING MINIMUM ENGINE HEIGHT 4 See Figure 10 This procedure MUST be performed prior to removing the engine from the vessel. With the engine compartment open, position a long level across the transom running fore and aft. 2. Have a friend or assistant steady the level while you measure from the bottom edge of the tool to the top of the exhaust elbow. Record the distance as "1". 3. Now measure from the bottom of the level to the static water line on the drive unit. Record the distance as Subtract the elbow measurement (1)from the static waterline measurement (2). If the result is less than 14 in. an exhaust elbow high rise kit must be installed (available from your local parts supplier). ENGINE MECHANICAL-FORD V8 ENGINES 6-5 Fig. 10 Use a level to determine minimum engine height Fig. 11 Install the alignment through the gimbal bearing ENGINE ALIGNMENT And 1990 See Figures 11 and 1 Engine alignment is imperative for correct engine installation and also for continued engine and drive operation. It is a good idea to ensure proper alignment every time that the drive or engine has been removed. Engine alignment is checked by using OMCalignment tool and handle Engine alignment is adjusted by raising or lowering the front engine With the drive unit off the vessel, slide the alignment tool through the gimbal bearing and into the engine coupler. It should slide easily, with no binding or force. If not, check the gimbal bearing alignment as detailed in the Drive Systems section. If bearing alignment is correct, move to the next step. 2. your engine utilizes a jam nut on the bottom of the mount bolt, loosen it and back it off at least 112 in. 3. Loosen the lock nut and back it off. 4. Now, determine if the engine requires raising or lowering to facilitate alignment-remember, the alignment tool should still be in position. Tighten or loosen the adjusting nut until the new engine height allows the alignment tool to slide freely. 5. Hold the adjusting nut with a wrench and then tighten the lock nut to 40-50 ft. Ibs. (54-60 Nm) on engines or 50-70 ft. Ibs. (68-95 Nm) on 1993-96 engines. If your engine uses a jam nut, cinch it up against the lock nut. 6. Remove the alignment tool and handle. 1987-89 Engines CULT v See Figures 11 and 12 Engine alignment is imperative for correct engine installation and also for continued engine and drive operation. It is a good idea to ensure proper alignment every time that the drive or engine has been removed. Engine alignment is checked by using OMCalignment tool and handle Enqine alignment is adjusted by or lowering the front engine With the drive unit off the vessel, slide the alianment tool throuah the gimbal bearing and into the engine coupler. It shouldslide easily, with binding or force. If not, check the gimbal bearing alignment as detailed in the Drive Systems section. If bearing alignment is correct, move to the next step. 2. There will be a slot on the lower mount providing access to the head of the mount bolt. Slide a 15116 in. open end wrench into the slot and hold the bolt so that you can loosen the upper lock nut. It is not necessary to remove the nut. Fig. 12 A good view of the front engine mount and its components 3. Now. determine if the enaine reauires raisina or lowerina to facilitate alignment-remember, the tool should be in 4. There should be a total of 4 slotted shims situated above below the rubber mount; rearrange the shims until the new engine height allows the alianment tool to slide freelv. The shims are slotted and will slide and out of mount easrly Never more than 4 on an mount 5 Install the nut and to 100-120 ft. Ibs. (136-63 Nm). 6. Remove the alignment tool and handle. ENGINE MECHANICAL-FORD V8 ENGINES 1 Support Screw Height Fig. 13 Always preset the support screw height on engines REMOVAL INSTALLATION V8 Engines See Figures 12 and 13 Position an engine hoist over the engine and hook it up to the two engine lifting eyes (usually front starboard side, rear port side). 2. Measure the distance between the top of the large washer on the mount and the flat on the lower side of the mounting bracket. Record it. 3. Remove the two lag bolts on each side of the mount where it rests on the stringer. 4. Raise the engine just enough to allow working room for removing the mount. 5. Remove the two mount bracket-to-engine mounting bolts with their lock washers and lift out the mountibracket. Some may use bolts of mark them so you their oriainal 6. Carefully position the mount in a vise. Position a wrench over the head of the adjusting bolt, just underneath the mount to hold the shaft and then remove the upper nut and washer. Lift off the bracket. 7. Remove the two lock nuts from the bolt and slide out the adjusting bolt. Remember which washer goes where. To Install: 8. Drop the small washer over the shaft and then slide the adjusting bolt up through the mount. Position the large washer over the bolt so it rests on the mount and then spin on the first (lower) lock nut and tighten it to 60-75 (81-102 Nm). 9. Check that the mount support screw height is set to 112 in. on the 1993 engine or 114 in. on the 1994-96 On the 1993 set the screw to 7/16 in. while on the 1994-96 engines set the screw to 3116 in. On all engines, make sure there is no paint on the head of the bolt, or on the mating surface at the block. 1987-92 engines do not use a height support bolt, 10. Spray the two mounting bolts with Loctite Primer N and allow them to air dry. Once dry, coat the bolts with Loctite or OMC Nut Lock and attach the mount bracket to the engine. Tighten the bolts to 32-40 ft. Ibs. (43-54 Nm). On engines with a height support bolt, tighten the correct support bolt for your engine until it just contacts the cylinder block. Now tighten it an additional 114 of a turn. 12. Screw on the middle lock nut and washer onto the mount bolt and then position the mount bracket over the bolt. Install the washer and upper adjusting nut and check the measurement taken previously. Move the upper and middle lock nuts up or down until the correct specification is achieved. 13. Position the mount over the lag screw holes and then slowly lower the engine until all weight is off the hoist. Install and tighten the lag screws securely. 14. Hold the middle nut with a wrench and then tighten the upper nut to 40-50 ft. Ibs. Nm) on 1989-92 engines or 50-70 ft. (68-95 Nm) on 1993-96 engines. If you're confident that your measurements and subsequent adjustment place the engine exactly where it was prior to removal, then you are through. If you're like us though, you may want to check the engine alignment before you fire up the engine. V8 Engines Position an h engine lifting eyes front starboard side, rear port sidej. 2. Remove the 2 lag bolts on each side of the mount where it rests on the stringer. 3. Raise the engine just enough to allow working room for removing the mount. 4. Remove the 3 mount bracket-to-engine mounting bolts with their lock washers and lift out the mountibracket. of different lengths; so you locations. 5. Hold the mount bolt head and remove the upper lock nut. Note the positions of the adjusting shims and then remove them. 6. Pry out the rubber mounts. To Install: 7. Coat the smaller side of a new rubber mount with soapy water and then press it into the top of the mount bracket. Repeat the procedure with the lower rubber mount. 8. Slide a small flat washer over the mount bolt and then insert the bolt into the lower mount foot and through the rubber mounts. Slide the larger washer over the end of the bolt and thread on the lock nut. 9. Insert the slotted shims around the bolt so that they are in the same position as when removed and then tighten the lock nut to 100-120 ft. Ibs. (136-63 Nm). 10. Position the mount against the cylinder block, install the 3 mounting bolts and tighten them to 32-40 ft. Ibs. (43-54 Nm). 11. Install the lag bolts and tighten them securely. 12. Remove the engine hoist. REMOVAL INSTALLATION See Figure 14 CULT Remove the engine as detailed previously. 2. Loosen the two bolts and remove the mount from the transom plate. Remember, will have removed the top lock nut and the washer during engine removal. 3. Hold the square nut with a wrench and remove the shaft bolt. Be sure to take note of the style and positioning of the two mount washers as you are removing the bolt. Mark them, lay them out, or write it down, but don't forget their orientation!! To Install: 4. Slide the lower of the two washers onto the mount bolt, exactly as it came off. 5. Slide the bolt into the flat (bottom) side of the rubber mount, install the remaining washer (as it came off!) and then spin on the square nut. Do not tighten it yet. Incorrect washer installation will cause excessive vibration during engine operation. 6. Turn the assembly upside down and clamp the square nut in a vise. Spin the assembly until the holes in the mounting plate are directly opposite any two of the flat sides on the nut. This is important, otherwise the slot on the engine pad will not engage the mount correctly. Secure the mount in this position and tighten the bolt to 44-52 Ibs. (60-71 Nm). ENGINE MECHANICAL-FORD V8 ENGINES 6-7 Fig. 15 Lift off the cylinder head cover 7 Remove the mount from the vise and position the transom plats Install the bolts and washers and each to 20-25 ft Ibs. (27-34 Nm). 8 Install the engine, making sure that the slot in the engine pad engages the square nut correctly. Install the two washers and locknut and to 28-30 ft. Ibs (38-41 Nm) Fig. 14 A good look at the rear mount REMOVAL INSTALLATION See Figures 15 and 16 In order to perform this procedure efficiently, we recommend removing the exhaust manifold in order to have sufficient working room to remove the cylinder head cover. Although not completely necessary, it's worth the extra effort to avoid the aggravation of working around the manifolds. Please refer to the manifold procedure later in this section. 1. Open or remove the engine compartment hatch. Disconnect the negative battery cable. 2. Loosen the clamp and remove the crankcase ventilation hose at the cover (if equipped). Carefully move it out of the way. 3. Tag and disconnect any lines, leads or hoses that might be in the way of removal. In some instances you may be able to simply secure them out of the way without disconnecting them-you be the judge. 4. If your engine has a spark plug wire retainer attached to the cover, the wires or remove the retainer and then tag and disconnect the plug wires at the spark plugs. 5. Loosen the cover mounting bolts and lift off the cylinder head cover. Take note of any harness or hose retainers and clips that might be attached to certain of the mounting bolts; you need to make sure they go back in the same place. To Install: 6. Clean the cylinder head and cover mounting surfaces of any residual gasket material with a scraper or putty knife. 7. Position a new gasket onto the cover making sure that the tabs in the gasket engage the notches in the cover. Position the cover (don't forget the J-clips!) on the cylinder head and then tighten the mounting bolts to 60-72 inch Ibs. (6.8-8.1 Nm) on 1987-93 engines or 36-60 inch Ibs. (4-6 Nm) on 1994-96 engines. Make sure any retainers or clips that were removed are back in their original positions. On 1987-93 engines, wait 2 minutes and then retighten all of the bolts to the same specification once again. 8. Connect the crankcase ventilation hose and any other lines or hoses that may have been disconnected. Check that there were no other wires or hoses you may have repositioned in order to gain access to the cover. 9. Install the exhaust manifold. 10. Connect the battery cables. REMOVAL INSTALLATION See figures and 20 Open or remove the engine hatch cover and disconnect the negative battery cable. Remove the cylinder head cover as detailed previously. 2. Bring the piston in the No. 1 cylinder to TDC. If servicing only one arm, bring the piston in that cylinder to TDC. The No. 1 cylinder is the first cylinder at the starboard side of the engine. 3. Loosen and remove the rocker arm bolt. Lift out the oil deflector on the ad the fulcrum on all engines. 4. Lift the arm itself off of the mounting stud (or boss) and pull out the Lift off the guide before removing the if it didn't come off with the rocker. It is very important to keep each cylinder's component parts together as an assembly. We suggest drilling a set of holes in a and positioning the pieces in the holes. ENGINE MECHANICAL-FORD V8 ENGINES To Install: 5. Clean and inspect the rocker assemblies. If any scuffing, wear or obvious deterioration is found replace the entire assembly (rocker, fulcrum and and guide). Roll each push rod across a flat, even surface (countertops work great for this); if it does not roll smoothly, replace it. 6. Coat all bearing surfaces of the rocker assembly (valve stem tips, arm contact surfaces, fulcrum seat and push rod tip) with or Ford Multi-Purpose grease. 7. Slide the push rods into their holes. Make sure that each rod seats in its socket on the tappet. 8. lnstall a remote starter. 9. Bump the engine over until the No. cylinder is at TDC after the compression stroke. Valve arrangement running from front to back on the port side is: E- I-E-l-E-l-E-I, while on the starboard side it is: l-E-l-E-I-E-I-E. Install the guide, rocker arm, fulcrum and bolt on the following valves: and engines No. I:intake and exhaust No. 4: exhaust No. 5: exhaust No. 7: intake No. 8: intake engines No. : intake and exhaust No. 3: exhaust No. 4: intake No. 7: exhaust No. 8: intake Fig. 17 Exploded view of the rocker arm engines Fig. 18 Exploded view of the rocker arm assembly-7.51 engines 11. Now bump the crankshaft around 180" from TDC and install the guide, rocker arm, fulcrum, deflector and bolt on the following valves: and engines No. 2: exhaust No. 4: intake No. 5: intake No. 6: exhaust engines No. 2: exhaust No. 3: intake No. 6: exhaust No. 7: intake 12. Now bump the crankshaft around a further (for a total of from TDC where you started) on the engines. On the engine, bump the crankshaft around a further (that's a full 360" from TDC, plus an additional Install the guide, deflector, rocker arm, fulcrum and bolt on the following valves: and engines No. 2: intake No. 3: intake and exhaust No. 6: intake No. 7: exhaust No. 8: exhaust engines No. 2: intake No. 4: exhaust No. 5: intake and exhaust No. 6: intake No. 8: exhaust Fulcrum Bolt Oil Deflector ENGINE MECHANICAL-FORD V8 ENGINES 13. Now tighten all the fulcrum bolts to 18-25 ft. Ibs (24-34 Nm). The fulcrum base MUST be inserted in the slot on the cylinder head BEFORE tightening any of the bolts. 14. No additional adjustment of the valves is necessary as the lash is set automatically when the positive-stop rocker is tightened to specifications. To make sure that all components are operating properly though, it's a good idea to check the valve clearance as detailed following. 15. Install the cylinder head cover, connect the battery cable and check the idle speed. VALVE CLEARANCE CHECK See Figures 19 and 20 Positive-stop rocker arm bolts virtually eliminate the need for a regular valve clearance adjustment, but wear, tear or damage will sometimes only be revealed by virtue of a preliminary clearance check with the hydraulic lifter in the fully collapsed position. Clearance figures for each engine are detailed in the Engine Specification chart and should be checked between the rocker arm and the tip of the valve stem with a feeler gauge. Valve arrangement running from front to back on the port side is: E- I-E-I-E-I-E-I, while on the starboard side it is: I-E-I-E-I-E-I-E. Locate the purple wire coming off of the I terminal on the starter solenoid, tag it and disconnect it-this will prevent the engine from starting when you install a remote starter. Install a remote starter. Bump the engine over until the No. cylinder is at TDC after the compression stroke. 3. Install a Lifter Compressor tool onto the appropriate rocker arm and slowly apply enough pressure to bleed down the lifter until the rod is bottomed out. Check the clearance on the following valves: and engines No. : intake and exhaust No. 4: exhaust No. 5: exhaust No. 7: intake No. 8: intake engines No. 1: intake and exhaust No. 3: exhaust No. 4: intake No. 7: exhaust No. 8: intake 4. Now bump the crankshaft around from TDC, install the tool on the appropriate rocker arm, and check the clearance on the following valves: and engines No. 2: exhaust No. 4: intake No. 5: intake No. 6: exhaust engines No. 2: exhaust No. 3: intake No. 6: exhaust No. 7: intake 5. Now bump the crankshaft around a further (for a total of from TDC where you started) on the engines. On the engine, bump the crankshaft around a further (that's a full from TDC, plus an additional Install the tool and check the clearance on the following valves: and engines No. 2: intake No. 3: intake and exhaust No. 6: intake No. 7: exhaust No. 8: exhaust engines No. 2: intake No. 4: exhaust No. 5: intake and exhaust: No. 6: intake No. 8: exhaust 6. Allowable clearance on all valves should be: 93 in. (1 in. in. 7. If clearance is not within specifications on 1986-93 engines, OMC makes replacement that are available either 0.060 in. longer or shorter than stock. If clearance is lower than spec, install the shorter rod; if higher than spec, install the longer Valve clearance that is out of specification on 1994-96 engines will require replace components in the valvetrain. Fig. 19 Crankshaft positioning while installing the rockers on and engines. The No. 1 piston is at TDC after the compression stroke in position 1. Round two will have the crank moved to position 2. While round three will move the crank an additional 90" to position 3 Fig. 20 Crankshaft positioning while installing the rockers on engines. The No. 1 piston is at TDC after the compression stroke in position 1. Round two will have the crank moved 180" to position 2. While round three will move the crank an additional 270" to position 3 6-10 ENGINE MECHANICAL-FORD V8 ENGINES REMOVAL INSTALLATION ERATE If you have installed a new camshaft, always use new lifters. Using compressed air, thoroughly clean all dirt and grit from the cylinder head and related components. compressed air is not available, we highly recommend that you DO NOT proceed with this procedure. It is EXTREMELY important that no dirt gets into the lifter recesses before completing the installation. 2. Remove the cylinder head cover. 3. Remove the intake and exhaust manifolds. 4. Loosen the rocker arms and pivot the rockers off of the pushrods. 5. Remove the from the block, being very careful to keep track of where each one came from. As always, we recommend using a 2x4 with holes drilled in it-mark the holes for each rod and insert into the appropriate hole. 6. Remove the lifters. Although they should come right out, you may want to use a magnet; or more likely, you will need to use a lifter extractor tool for the or on the to extract each lifter. Once again, we suggest using a 2x4 with holes drilled in it to store the rods and lifters; you'd be amazed at how quickly this job will fall apart if someone walks in and kicks the components that you have laid out on the floor! To Install: 7. Clean all components thoroughly and let dry completely, use compressed air if at all possible. 8. Make sure that the push rod oil passages are clean and clear. Inspect the camshaft contact surface on the bottom of each lifter for excessive wear, galling or other damage. Discard the lifter if any of the above conditions are found. You'll probably want to check out the camshaft lobe for damage also. 9. Coat each lifter, bore and camshaft lobe with clean engine oil or Multi-Purpose grease, and then carefully install each one into its respective recess. 10. lnstall the into the sockets on the lifters and coat their tips with Ford Mullti-Purpose grease. Coat the valve stem ends as well. When reusing existing components, it is imperative that the lifters and push rods are installed in their original bores. 11. Lubricate the rockers and fulcrum seats with multi-purpose grease. Move the rockers into position and then tighten the bolt as detailed in the Rocker Arm procedure as detailed previously. 12. Check the valve clearance as previously detailed. Install the intake and exhaust manifolds. 14. lnstall the cylinder head cover. REMOVAL INSTALLATION And Engines See Figures and 24 DERATE Open or remove the engine compartment hatch. Disconnect the negative battery cable. 2. Loosen the clamp and remove the crankcase ventilation or PCV hoses at the cylinder head cover. Carefully move them out of the way. 3. Drain all water from the cylinder block and manifolds. Tag and disconnect all water hoses at the manifold and thermostat housing. Have some rags handy, since there will still be some water in them. Carefully move them out of the way. 5. Remove the thermostat housing. 6. Remove the flame arrestor and then disconnect the throttle cable at the carburetor. Remove the throttle cable bracket from the manifold. 7. Disconnect the fuel line and plug the line end and the carburetor fitting. If you have a non-flexible line, disconnect it at the fuel pump also. Move both the cable and fuel line out of the way. There should also be a fuel pump vent line connected to the carburetor-tag it, disconnect it and move it out of the way. 8. Tag and disconnect the lead at the ignition coil. 9. Remove the distributor cap with the leads still connected and set it aside temporarily. Mark the position of the distributor rotor to the distributor body. Scribe a match mark across the distributor and the manifold. Loosen the clamp bolt and remove the distributor. Please refer to the Electrical section for further details on distributor removal. DO NOT turn the engine over once the distributor has been removed. 10. Tag and disconnect the electrical leads at the ignition coil. Remove the coil and its bracket. 11. Tag and disconnect the lead at the temperature gauge sender unit. Tag and disconnect any other lines, leads or hoses that might be in the way of removal. In some instances you may be able to simply secure them out of the way without disconnecting them-you be the judge. 12. If your engine has a spark plug wire retainer attached to the cylinder head cover, unclip the wires or remove the retainer and then tag and disconnect the plug wires at the spark plugs. Move the wires (and the cap) out of the way. 13. Loosen and remove the 12 manifold mounting bolts (1 6 on the in the reverse order of the illustrated tightening sequence and then remove the manifold. Leave the carburetor and decel valve attached. There is a good likelihood you will need to pry the manifold off the block; be very careful that you don't scratch or mar the mating surfaces on the block, manifold or heads. To Install: 14. Carefully remove all remaining gasket material from the manifold mating surfaces with a scraper or putty knife. Be careful that you don't accidentally drop any old gasket into the crankcase or intake ports on the cylinder head. 15. Inspect the manifold and all mating surfaces for any cracks or nicks. Apply a 118 in. bead of RTV sealant to the forward and aft edges (4 corners) of the cylinder block mating surface where it meets the cylinder head. Make sure that you run the bead at least as wide as width of each seal. 17. lnstall the manifold gaskets onto the head. Position the cylinder block seals and run a 1116 in, bead of RTV sealant along the edge of each seal where it mates with the gaskets on the cylinder head. The sealer sets up fairly quickly, so don't dawdle here! 18. Carefully install the manifold into place so that all the bolt holes line up. Run your finger along the edge of all seal areas to make certain that they are still positioned correctly; if not, remove the manifold and reposition it again. Insert the bolts, tighten them finger-tight and then tighten all bolts in sequence to 23-25 ft. Ibs. (31-34 Nm) on the engines or 25-27 ft. Ibs. (34-40 Nm) on the When you're through, repeat the tightening sequence one more time and then make sure to recheck at the end of the season. Check the Torque Specifications chart for any further details on tightening needs. Tighten all bolts in the order shown in the illustration. 19. lnstall the thermostat housing and adaptor. lnstall the distributor making sure that the match marks align. Do the same with the cap and reconnect the spark plug wires. 21. lnstall the coil and bracket. Reconnect the electrical leads and the distributor lead. 22. Unplug the fuel and reconnect them. Connect the vent hose and the PCV hose. 23. lnstall all water hoses and tighten their clamps securely. 24. lnstall the throttle cable bracket and then connect the cable itself. Adjust it as detailed in the Fuel System section. lnstall the flame arrestor. 25. Connect all other lines, leads and hoses that may have been removed to facilitate manifold removal. 26. Connect the battery cable and start the engine. Check the ignition timing and idle speed. Check all hoses and seals for leaks. ENGINE MECHANICAL-FORD V8 ENGINES 6-11 SEALER (4-JOINTS) CYLINDER HEAD SEAL SURFACE OF CYLINDER BLOCK INTAKE GASKET INTAKE AN FOLD SEAL SEALER (4-SEALENDS) 21 Always use RTV sealer at the four block-to-head joints 22 Intake manifold tightening sequence-5.01 and engines 5.0 EFI, And Engines DERATE Upper Intake Manifold (Plenum) Please refer to the Exploded Views section for detailed illustrations of the upper manifold and related components. Open or remove the engine compartment hatch. Disconnect the negative battery cable. 2. Relieve the fuel system pressure as detailed in the Maintenance or Fuel System sections. 23 Intake manifold tightening sequence-7.51 engines Hos Thermostat O-ring Fig. 24 Exploded view of the intake manifold 3. Loosen the 4 retaining screws and lift of the engine's plastic cover. 4. Tag and disconnect the ISC solenoid and Throttle Position sensor leads at the throttle bodv. 5. Remove the lock nut and disconnect the throttle cable at the lever on the throttle body. Remove the 2 manifold mounting bolts at the rear of the plenum that secure the throttle cable bracket. Position the cable and bracket out of the way. 6. Tag and disconnect the pressure regulator hose and the fuel reservoir line at the rear of the plenum. 7. Tag and disconnect the PCV hose at the valve. 8. On the forward starboard side, tag and disconnect the vacuum line at the MAP sensor. Move it and the filter out of the way. 6-12 ENGINE MECHANICAL-FORD V8 ENGINES 9. Right next to the filter, remove the 2 forward plenum mounting bolts and lift off the shift bracket support. 10. At the module bracket next to the throttle body, tag and disconnect the high tension lead from the ignition coil, the primary lead also at the coil and the TFI-IV lead. 11. Remove the 2 remaining plenum screws and lift off the upper manifold with the throttle body attached. Be extremely careful of how you handle the and where you set it down, particularly the mating surfaces. You need also to safeguard against any foreign material entering the lower intake runners. To Install: 12. Carefully remove any remaining gasket material from the plenum and manifold mating surfaces. Make sure that any vacuum lines running under the center of the plenum are plastic tied correctly and in a position so they don't get crimped on installation. Never soak the plenum in commercial liquid cleaners or solvents. 13. Lay a new gasket onto the lower manifold runners. There are studs available to aid in positioning, but if you're careful and patient there should be no need for them. 14. Position the plenum onto the manifold in such a way that you do not dislodge the gasket. lnstall the 2 long mounting bolts and tighten them tight. 15. Coat the terminal with Electrical Terminal grease and reconnect the 3 leads at the module bracket. 16. lnstall the shift support bracket with the next two manifold screws and screw them down finger-tight. lnstall the throttle cable bracket with the 2 remaining manifold screws and then tighten all 6 mounting screws to 12-18 ft. Ibs. (16-24 Nm). 17. Reconnect the remaining vacuum lines. 18. Reconnect the throttle cable. Check for correct throttle operation and adjust if necessary. 19. Connect the battery cables. Lower lntake Manifold See Figures 21 and 25 Open or remove the engine compartment hatch. Disconnect the negative battery cable. 2. Drain all water from the cylinder block and manifolds. 3. Remove the upper intake as detailed previously. 4. Tag and disconnect all water hoses at the manifold and thermostat housing. Have some rags handy, since there will still be some water in them. Carefully move them out of the way. 5. Remove the thermostat housing and adapter. 6. Remove the distributor cap with the leads still connected and set it aside temporarily. Mark the position of the distributor rotor to the distributor body. Scribe a match mark across the distributor and the manifold. Loosen the clamp bolt and remove the distributor. Please refer to the Electrical section for further details on distributor removal. DO NOT turn the engine over once the distributor has been removed. 7. Tag and disconnect the lead at the temperature gauge sender unit. 8. Tag and disconnect any other lines, leads or hoses that might be in the way of removal. In some instances you may be able to simply secure them out of the way without disconnecting them-you be the judge. 9. If your engine has a spark plug wire retainer attached to the cylinder head cover, the wires or remove the retainer and then tag and disconnect the plug wires at the spark plugs. Move the wires (and the cap) out of the way. 10. Loosen and remove the 12 manifold mounting bolts in the reverse order of the illustrated tightening sequence and then remove the manifold. There is a good likelihood you will need to pry the manifold off the block; be very careful that you don't scratch or mar the mating surfaces on the block, manifold or heads. To Install: 11. Carefully remove all remaining gasket material from the manifold mating surfaces with a scraper or putty knife. Be careful that you don't accidentally drop any old gasket into the crankcase or intake ports on the cylinder head. Inspect the manifold and all mating surfaces for any cracks or nicks. 13. Apply a 118 in. bead of RTV sealant to the forward and aft edges (4 corners) of the cylinder block mating surface where it meets the cylinder head. Make sure that you run the bead at least as wide as width of each seal. 14. lnstall the manifold gaskets onto the head. Position the cylinder block seals and run a 1116 in, bead of RTV sealant along the edge of each seal where it mates with the gaskets on the cylinder head. The sealer sets up fairly quickly, so don't dawdle here! 15. Carefully install the manifold into place so that all the bolt holes line up. Run your finger along the edge of all seal areas to make certain that they are still positioned correctly; if not, remove the manifold and reposition it again. Insert the bolts, tighten them finger-tight and then tighten all bolts in sequence to 23-25 ft. Nm). When you're through, repeat the tightening sequence one more time and then make sure to recheck at the end of the season. Check the Torque Specifications chart for any further details on tightening needs. Tighten all bolts in the order shown in the illustration. 16. lnstall the thermostat housing and adaptor. 17. lnstall the distributor making sure that the match marks align. Do the same with the distributor cap and reconnect the spark plug wires. 18. lnstall the upper manifold. lnstall all water hoses and tighten their clamps securely. 20. Connect all other lines, leads and hoses that may have been removed to facilitate manifold removal. 21. Connect the battery cable and start the engine. Check the ignition timing and idle speed. Check all hoses and seals for leaks. REMOVAL INSTALLATION See Figures and 28 Open or remove the engine compartment hatch. Disconnect the negative battery cable. Fig. 25 Intake manifold (lower) tightening engines ENGINE MECHANICAL-FORD V8 ENGINES 6-13 2. Drain all water coolant from the engine, manifold and exhaust elbow as detailed in the Maintenance section. 3. Disconnect all lines at the manifold and move them out of the way. It's a good idea to tag these so that you can ensure proper reconnection. 4. Loosen the hose clamps (two) and then squirt a little soapy water in between the hose and the elbow. Disconnect the exhaust pipe hose (bellows) at the elbow and move it out of the way. Grasp the hose with both hands and wiggle it back and forth while pulling it off the elbow. Take note of where all the hose clamps were situated. you are unable to gain enough clearance to slide the hose off the elbow, remove it completely (as detailed elsewhere). 5. If you intend to remove the starboard manifold, unsnap the electrical cable from the retaining clip and move it out of the way on FL models. On Fi and models, remove the two bolts and lift off the ECA. 6. Carefully tag and disconnect the spark plug wires at the plugs and secure them above the manifold and out of the way. 7. Remove, disconnect, or simply move out of the way, any hoses or wires which may be in the way of removal on your particular engine. 8. Loosen the 8 manifold retaining nuts from the center outward and then pry off the assembly. 9. If necessary, loosen the four retaining bolts and remove the exhaust elbow from the manifold. To Install: 10. Carefully clean all residual gasket material from the head, manifold and elbow mating surfaces with a scraper or putty knife. Inspect all gasket surfaces for scratches, cuts or other imperfections. 11. Position a new gasket, without any sealant, on the cylinder head and install the manifold over the studs; making sure that everything is aligned properly. Tighten all nuts (with new lock washers) until they are just tight and then tighten them to 20-26 ft. (27-35 Nm). Starting in the center, and working your way out to the ends of the manifold. 12. If you removed the elbow, coat a new gasket with sealing compound and position it onto the manifold, making sure that everything lines up. Install the elbow. Tighten the mounting bolts to 12-14 ft. (16-20 Nm) on 1987- 90 engines, or 12-1 8 ft. (16-24 Nm) on engines, refer to the Exhaust Elbow procedures found later for more detail on installing the elbow. 13. Connect the exhaust pipelbellows to the elbow and tighten the clamps securely. 14. If you removed the manifold or elbow plugs for some reason, make sure that the threads are coated with sealant before screwing them back in. 15. Connect the hoses and tighten the clamps securely. Make sure that any miscellaneous lines or hoses that you may have moved or disconnected during removal are reconnected and routed properly. 17. Fill the system with water or coolant, connect the battery cable and start the engine. When the engine reaches normal operating temperature, turn it off and re-torque the manifold bolts. REMOVAL INSTALLATION See Figures and 28 1. Drain the cooling system. 2. Loosen the two hose clamps and slide off the exhaust hose (bellows). Grasp it with both hands and pull it off while wiggling it from side to side. If sticks, drip a little bit of soapy water around the lip. 3. If removing the starboard elbow on Fi and models, remove the screws and disconnect the ECA-or ESA on carbureted engines 4. Remove the four bolts, lock washers and washers from the elbow and lift it off the manifold. A little friendly persuasion with a soft rubber mallet may be necessary! Be careful though, no need to take out all your aggressions on the poor thing. 5. Remove the gasket and discard it. To Install: 6. Clean the mating surfaces of the manifold and elbow thoroughly, coat both sides of a new gasket with Gasket Sealing compound and position it onto the manifold flange. 7. Position the elbow on the manifold so the bolt holes are in alignment. Position any anchor brackets or mounting hardware for other components and then install the four mounting bolts and their washers. Tighten all four to 12-14 ft. Ibs. Nm) on 1987-90 engines, or 12-18 ft. Ibs. (16-24 Nm) on 1991-96 engines. 8. Install the on the starboard elbow and tighten the screws securely. 9. Slide the exhaust hose, while wiggling it, all the way onto the elbow. Position the two clamps in their channels and tighten the clamp screws securely. Coating the inside of the hose with a soapy water solution will help you slip it on. REMOVAL INSTALLATION See Figures and 30 Starting with the upper hose, loosen all four hose two on top of the hose and two on the bottom. 2. Drizzle a soapy water solution over the top of the hose where it mates with the exhaust elbow and let it sit for a minute. 3. Grasp the hose with both hands and wiggle it side-to-side while pulling down on it until it separates from the elbow. 4. Now wiggle it while pulling upwards until it pops off the intermediate exhaust pipe. 5. The lower hose should be removed in the same manner as the upper. 6. Check the hose for wear, cracks and deterioration. 7. Coat the inside of the lower end of the lower hose with soapy water and wiggle it into position on the Y-pipe (lower). Remember to install the two clamps before sliding it over the end of the pipe. There is a step about 1 112 in. into the inside of one end on each the upper and lower hoses. The stepped side of BOTH hoses should fit over the intermediate pipe. This means that the stepped side on the upper hose faces DOWN, and the stepped side on the lower hose faces UP! 8. Slide the two clamps over the upper end of the lower hose and then coat the inside with the soapy water solution and insert the bottom of the intermediate pipe into it fully until it seats on the step. Tighten the clamp screws securely. 9. Coat the inside of the lower end of the upper hose with soapy water and wiggle it into position on the intermediate pipe until it meets the step. Remember to install the two clamps before sliding it over the end of the pipe. 10. Slide two clamps over the upper end, lubricate the inside with soapy water and wiggle the hose over the elbow. 11. Tighten all four clamp screws securely. See Figure 26 1. It is unlikely you will be able to get the pipe off without removing the engine, so remove the engine as previously detailed. 2. Loosen the retaining bolts at the transom shield and then remove the exhaust pipe. Carefully scrape any remnants of the seal from the pipe and transom mounting surfaces. The pipe mounting holes in the transom shield utilize locking inserts. Never clean the holes or threads with a tapping tool or you risk damaging the locking feature of the threads. 3. Coat a new seal with 3M Rubber Adhesive and position it into the groove on the transom shield mating surface. 4. Coat the mounting bolts with Gasket Sealing Adhesive. Position the exhaust pipe, insert the bolts and tighten them to 20-25 ft. (27-34 Nm). 5. Install the engine. Exhaust Elbow Fia. 26 view of the exhaust ENGINE MECHANICAL-FORD V8 ENGINES Exhaust Elbow Mounting Bolt, P R Elbow Lower (Collector) 27 Exploded view of the exhaust manifold and components- engine EXHAUST VALVE (FLAPPER) REPLACEMENT 6. Remove the exhaust hoses afnd the intermediate exhaust pipe. The flapper is located in the upper end of the y-pipe. 7. The valve is held in place by means of a pin running through two bushings in the sides of the pipe. Position a small punch over one end of the pin and carefully press the pin out of the pipe. Make sure you secure the valve while removing the retaining pin so it doesn't fall down into the exhaust pipe. 8. Press out the two bushings and discard them. Coat two new bushings with Scotch Grip Rubber Adhesive and press them back into the sides of the pipe. 9. Position the new valve into the pipe with the long side DOWN. When looking at the valve, the molded retaining rings are off-center-the side with the rings should face the top of the pipe. When the valve is in place, coat the pin lightly with engine oil and slowly slide it through one of the bushings, through the two retaining holes on the valve and then through the opposite bushing. Make sure the pin ends are flush with the sides of the pipe on both sides. 10. Install the exhaust hose. Fig. 28 Exploded view of the exhaust manifold and components- engine Fig. 29 A good look at the upper hose ... Fig. 30 ...and the lower hose-not all engines will have the bulge in the lower hose like shown here 6-16 ENGINE MECHANICAL-FORD V8 ENGINES REMOVAL INSTALLATION See Figure 31 CULT More times than not, this procedure will require the of the engine. Your boat and its unique engine installation will determine this, but the procedure is almost always easier with the engine removed from the boat. 1. Remove the engine as previously detailed in this section. 2. If you haven't already drained the engine oil, do it now. Make sure you have a container and lots of rags available. 3. Remove the oil dipstick and then remove the dipstick 4. Remove the oil withdrawal tube from the oil drain plug fitting. 5. Loosen and remove the oil pan retaining bolts, studs and nuts, starting with the center fasteners and working out toward the pan ends. Lift off the pan braces and then lightly tap the pan with a rubber mallet to break the seal and then lift it off the cylinder block. If your engine stand will allow for rotating the engine, you'll find that this will be easier with the pan facing To Install: 6. Clean the pan mating surfaces of any residual gasket material with a scraper or putty knife. Make sure that no old gasket material has been pressed into the retaining bolt holes in the pan, block or front cover. Clean the pan itself thoroughly with solvent. 7. Coat the mating surfaces of the oil pan and cylinder block with an oil- resistant sealant and then position a new gasket onto the block-make sure all the holes line up. In place of a one piece gasket like the other engines, the uses 2 side gaskets and 2 seals-make sure that the tabs in the front cover seal and the rear main bearing seal are over the edges of each side gasket. The two-piece oil pump utilizes two pump rotors and a pressure regulator valve enclosed in a housina. A baffled tube is attached to the body of the pump. dlpasses the screen, through the pump and then through the oil filter. REMOVAL INSTALLATION See Figures and 33 Remove the oil pan as previously detailed. you probably need to remove the engine for this procedure. 2. Loosen the two inlet tube mounting bolts and the bracket bolt and then remove the pick-up 3. Loosen and remove the 2 pump mounting bolts and lift off the pump assembly along with the intermediate shaft. 4. Pull out the driveshaft and retainer. 5. Loosen the 4 cover mounting screws and lift off the pump cover. 6. Match mark the two rotors where they mesh and then lift out the outer rotor and shaft. 7. Pull out the cotter pin retaining the relief valve plug. To remove the plug itself, you will need to drill a small hole in the plug, insert a self-tapping screw and pull it out with a pair of pliers-don't lose the spring. Now you can remove the valve itself. Are you sure you want to do this? 8. Clean all components in solvent and dry thoroughly. Inspect the pump body and rotors for cracks, excessive wear or other damage 9. lnstall the relief valve into the housing cover with a new spring. Press in the plug until it seats itself and then install a new cotter pin. 10. lnstall the outer rotor and shaft into the housing so the earlier marks line up. Fill the housing with fresh engine oil, install the pump cover and tighten the screws to 72-120 inch (8-16 Nm). 11. Now fill the pump with engine oil through the inlet to prime it-wiggle the pump shaft to aid the oil in coating all internal parts. 12. Insert the intermediate shaft into the distributor socket until it seats itself fully. The stop on the shaft should just contact the crankcase, so position it until this is the case. 13. When the stop is positioned correctly, insert into the pump and install them as an assembly. Do NOT force anything into position; if it will not seat properly, the drive is probably not aligned with the distributor shaft correctly. Rotate the intermediate shaft until they align. Tighten the oil pump bolts to 22-32 ft. Ibs. (30-43 Nm). 14. lnstall the pick-up tube and screen. Tighten the tube-to-pump bolts to 10-15 ft. Ibs. the bracket bolt to 22-32 ft. (30-43 Nm). , 15. lnstall the oil pan and engine. Fill the engine with oil. 8. Move the pan onto the block; don't dawdle here because the RTV sealant in the orevious steo sets verv auicklv. It is verv . , . that you ensure all the holes line 9. Position the pan braces on each side and then install a bolt at each corner to hold the pan in place. lnstall the rest of the bolts and tighten the 1/4-20 bolts to 84-108 inch Ibs. (9.5-12.2 Nm) and the 5/16-18 bolts to 108- 132 inch (12.2-14.9 Nm) from the center outward. On the fuel injected engines, tighten all bolts to 9-11 Ibs. (13-14 Nm); from the center outward. 10. lnstall the oil drain plug or the oil drain fitting and finger tighten the bolt. Rotate the fitting and then attach the withdrawal tube. Tighten the fitting bolt and flare nut to 15-18 ft. Ibs. (20-24 Nm). lnstall the engine (if removed). Refill with all fluids. Run the engine up to normal operating temperature, shut it off and check the pan for any leaks. Fig. 31 Exploded view of a typical oil pan and pump-5.01 and engines O-ring Tube Pick-up Screen REMOVAL INSTALLATION Over the years, these engines were equipped in a variety of configurations-flywheel and torsional damper, flywheel, damper and coupler, flywheel and coupler, etc. And for a number of years, some models also had a timing ring attached. Early models are usually the ones equipped with a damper, while and DP models usually were equipped with the coupler. King Cobra models are usually the ones that use the timing ring. Although we have attempted to narrow the applications in the following procedures, it was not always year or model specific. Please read the procedures FIRST in order to determine which one is appropriate for your particular engine's configuration. Models With A Torsional Damper CULT Over the years, these engines were equipped in a of configurations-flywheel and torsional damper, flywheel, damper and coupler, flywheel and coupler, etc. And for a number of years, some models also had a timing ring attached. Early models are usually the ones equipped with a damper, while Cobra, SP and DP models usually were equipped with the coupler. King Cobra models are usually the ones that use the timing ring. Although we have attempted to narrow ENGINE MECHANICAL-FORD V8 ENGINES 6-17 Fig. 32 Remove the pick-up tube ... Fig. 33 ...and then remove the pump itself To Install: the applications in the following procedures, it was not always year or model specific. Please read the procedures FIRST in order to determine which one is appropriate for your particular engine's configuration. 1. Remove the engine as detailed previously. 2. Loosen the bolts and remove the flywheel housing and cover plate. 3. Remove the three mounting bolts and pull off the rear torsional damper. 4. Remove four of the six flywheel retaining bolts. Loosen the other two, anv two is fine, and back them out about half wav. the two bolts as a carefully pull the flywheel off of the crankshaft Remove the two bolts and flywheel. To Install: 5. Position the flywheel over the dowel pin on the flange and make sure that the holes line up correctly. Coat the bolt threads with engine oil, install them and tighten to 59 Ibs. (82 Nm). Tighten the six bolts a diagonal star pattern. 6. lnstall the torsional damper and tighten the bolts securely. 7. lnstall the housing and plate. Coat all mounting bolts with engine oil and the 9116 housing bolts to 30 ft. Ibs. (41 Nm), tighten the 5116 in. plate bolts securely. 8. lnstall the engine. Models With A Timing Ring See Figures 34 and 35 Over the years, these engines were equipped in a variety of configurations-flywheel and torsional damper, flywheel, damper and coupler, flywheel and coupler, etc. And for a number of years, some models also had a timing ring attached. Early models are usually the ones equipped with a damper, while Cobra, SP and DP models usually were equipped with the coupler. King Cobra models are usually the ones that use the timing ring. Although we have attempted to narrow the applications in the following procedures, it was not always year or model specific. Please read the procedures FIRST in order to determine which one is appropriate for your particular engine's configuration. 1. Remove the engine from the boat as detailed previously in this section. 2. Loosen and remove any connections attached to either of the ground studs on each side of the flywheel. Move the electrical leads out of the way. 3. Loosen the 5 retaining bolts and slide out the lower housing cover. 4. Although not strictly necessary, we recommend removing the starter. 5. Locate the timing sensor cover on the housing, loosen the two nuts and lift off the cover. Remove the two nuts and washers and then pull out the sensor and position it out of the way. 6. Cut the plastic tie that secures the housing drain hose and the pull the hose out of the fitting. 7. Remove the flywheel housing retaining nutslbolts and pull off the housing. Take note of the positioning of the oil cooler and its bracket. 8. Slide an offset wrench behind the coupler and loosen the six flywheel mounting nuts gradually and as you would the lug nuts on your car or truck-that is, in a diagonal star pattern. Remove the coupler. 9. Mark the dowel hole on the timing ring and pry it off the flywheel. Remove the flywheel. 10. Thoroughly clean the flywheel mating surface and check it for any nicks, cracks or gouges, Check for any broken teeth. lnstall the over the dowel on the crankshaft 12. Position ring over the locating pin making sure the pin is in the correct hole--you did mark it, right? Press the ring into position. 13. Slide the coupler over the studs so that it sits in the recess on the flywheel. lnstall new lock washers and tighten the mounting nuts to 40-45 ft. Ibs. (54-61 Nm). Once again use the star pattern while tightening the bolts. 14. lnstall the flywheel housing and attach the oil cooler. Tighten the to 32-40 ft. Ibs. (43-54 Nm). 15. lnstall the washer, lock washer and inner nut on the ground stud and tighten it to 15-20 ft. Ibs. (20-27 Nm). Attach the electrical leads, install another lock washer and then tighten the outer nut securely. Slide the drain hose in and attach it with a new plastic tie. 17. Position the timing sensor onto the mounting studs and press in on the spring tab so that the sensor seats itself correctly over the timing ring. lnstall the washers and nuts, with the tab still depressed, and tighten them to 48-64 inch Ibs. (5-7 Nm). Once the nuts are tightened, press in on the spring tab again and that the tab DOES NOT touch the timing ring. If it does, loosen the nuts and try it again. If the sensor tab comes in contact with the teeth of the timing ring, it will be damaged on engine start-up. 18. lnstall the sensor and tighten the nuts to 48-64 inch Ibs. (5-7 Nm). 19. Coat both sides of a new gasket with Gasket Sealing Compound and position it onto the cover. Slide the cover into position and tighten the bolts to inch Ibs. (7-9 Nm). 20. Install the engine. Models With A Coupler See Figures and 36 Over the years, these engines were equipped in a variety of configurations-flywheel and torsional damper, flywheel, damper and coupler, flywheel and coupler, etc. And for a number of years, some models also had a timing ring attached. Early models are usually the ones equipped with a damper, while Cobra, SP and DP models usually were equipped with the coupler. King Cobra models are usually the ones that use the timing ring. Although we have attempted to narrow the applications in the following procedures, it was not always year or model specific. Please read the procedures FlRST in order to determine which one is appropriate for your particular engine's configuration. Remove the engine from the boat as detailed previously in this section. 2. Loosen and remove any connections attached to either of the ground studs on each side of the flywheel. Move the electrical leads out of the way. 3. Although not strictly necessary, we recommend removing the starter. 4. Loosen the 4 or 5 retaining bolts and slide out the lower housing cover. 6-18 ENGINE MECHANICAL-FORD V8 ENGINES Fig. 34 Remove the cover ... I Fig. 35 ...and then pull off the coupler after removina the bolts 5. Cut the plastic tie that secures the housing drain hose and the pull To Install: Fig. 36 Tighten the mounting bolts in a criss-cross pattern the hose out of the fitting. 6. Remove the oil cooler and bracket, take note of the positioning of both and secure them out of the way. 7. Remove the flywheel housing. 8. Slide an offset wrench behind the coupler and loosen the six flywheel mounting nuts gradually and as you would the lug nuts on your car or truck-that is, in a diagonal star pattern. 9. Remove the coupler and then the flywheel. To Install: 10. Thoroughly clean the flywheel mating surface and check it for any nicks, cracks or gouges. Check for any broken teeth. 11. lnstall the flywheel over the dowel on the crankshaft. 12. Slide the coupler over the studs so that it sits in the recess on the flywheel. lnstall new lock washers and tighten the mounting nuts to 40-45 ft. Ibs. (54-61 Nm) except on 1992 engines where the spec is 35-40 ft. (47- 54 Nm). Once again use the star pattern while the bolts. 4. lnstall the flywheel housing and attach the oil cooler. Tighten the bolts to 28-36 ft. (38-49 Nm) on 1987-91 engines or 32-40 ft. Ibs. (43-54 Nm) on engines. 13. lnstall the washer, lock washer and inner nut on the ground stud and tighten it to 20-25 ft. Ibs. (27-34 Nm) on 1987-91 engines or 15-20 ft. (20-27 Nm) on 1992-96 engines. Attach the electrical leads, install another lock washer and then tighten the outer nut securely. 14. Coat both sides of a new gasket with Gasket Sealing Compound and position it onto the cover. Slide the cover into position and tighten the bolts to 60-84 inch Ibs. (7-9 15. Slide the drain hose in and attach it with a new plastic tie. lnstall the engine. REMOVAL INSTALLATION And Engines See Figures 37 and 38 It is not necessary to remove the oil pan or rear main bearing cap when removing the one-piece oil seal on these engines although you may find it easier to do just that. 1. Remove the engine. 2. Remove the flywheel housing and cover as detailed in this section. 3. Remove the engine coupler and flywheel from the engine as detailed in this section. 4. Using a sharp awl or punch, carefully punch a hole into metal surface of the seal between the cylinder block and the lip. lnstall a slide hammer screw in the threaded end and remove the seal. Be very careful not to scratch or mar the seal or groove surfaces. 6. Thoroughly clean the groove surface. 7. Coat the new seal with clean engine oil. 8. On engines, position it into a Seal Driver so that the seal's lip faces the cylinder block. Position the driver and seal over the crankshaft and then thread the attaching screws into the holes in the crankshaft. Tighten them securely, and alternately, until the seal is fully seated in the groove. The rear edge of the seal must be within 0.005 in. of the outer edge of the cylinder block. 9. On engines, insert the seal, lip facing forward, into a Seal Driver and then position the tool over the centerline of the crankshaft. Keeping the tool perfectly straight, hit the drive end with a mallet until the leading edge of the tool comes into contact with the cylinder block. 10. On either engine, inspect the seal and groove surface after removing the tool to make sure nothing was damaged during installation. 11. lnstall the flywheel and engine coupler. lnstall the cover and flywheel housing. 12. lnstall the starter. lnstall the engine. Fig. 37 Use this driver on the engine... Fig. 38 ...or this one on the engine ENGINE MECHANICAL-FORD V8 ENGINES 6-19 Engines Cylinder Block CULT See Figures and 41 in. Fig. 40 Position the new upper seal as shown ... These engines utilize a split-lip style rear main seal. The seal can be removed without removing the crankshaft. You will need to remove the engine for this procedure though. Remove the engine as detailed previously in this section (although not strictly necessary, its highly recommended). 2. Remove the oil pan and pump as detailed previously in this section. 3. Loosen all of the main bearing cap bolts just enough so that the crankshaft drops down 1132 in. at the rear. 4. Loosen the retaining bolts and remove the rear main bearing cap. Carefully insert a small or awl and remove the lower half of the seal from the cap. Do not damage the seal seating surface. 5. Using a hammer and a small drift or punch, tap on the end of the upper seal until it starts to protrude form the other side of the race. Grab the protruding end with pliers and pull out the remaining seal half. OMC makes a seal removal tool for this purpose also, or many people will thread a small screw into one end of the seal and then it out that which way works best for you. Upper and lower seals must replaced as a pair. Never replace only one seal. 6. Clean the seal grooves thoroughly with a small bottle brush. Fig. 41 ...and then position the lower seal 7. Check that you have the correct new seals. Coat the entire seal half in clean engine oil. 8. Install the upper half of the seal (undercut side facing front of the engine) by rotating it on the journal until about 118 in. is protruding from the parting surface. Be very careful here, as you need to make sure that no seal rubber has been shaved off by the bottom edge of the seal groove. 9. Tighten up all bearing cap bolts (except the rear) to 95-105 ft. (129-142 Nm) to bring the crankshaft back up into position. 10. Insert the lower seal half into the main bearing cap in the same manner as you did with the upper seal. 11. Make sure that the caplblock mating surfaces and the seal ends are free of any oil and then apply a small amount of Perfect Seal to the cap at the rear of the top mating surface. Do not apply sealer forward of the side seal groove. 12. Install the bearing cap and tighten the bolts on all caps to 95-105 ft. Ibs. 13. Install the oil pump and pan. 14. Install the engine. 39 These engines use a split-lip oil seal REMOVAL INSTALLATION Disconnect the battery cables. See 2. Remove the bracket mounting bolts for the alternator, raw water and power steering pump. Swivel them in to relieve belt tension. 3. Remove the drive as detailed in the Maintenance section. 4. Drain the engine and manifolds. 5. Remove the three bolts and pull off the drive pulley attached to the balancer. 6. Remove the balancer retaining bolt and install special tool 6316-D onto the damper. Tighten the tool press bolt and remove the damper; don't lose the crankshaft OMC --that you DO NOT use a conventional gear puller for this procedure. To Install: 7. Inspect the crank key and then install it into the shaft. Using a little adhesive will make this easier. 8. Coat the front cover oil seal lip with Ford Multi-Purpose grease and then install the damper so that the key and keyway align. Use a proper installation tool to press the assembly into place on the crankshaft. Be sure that you thread the tool into the crankshaft at least in. to protect the threads. In a pinch you can use a block of wood and a plastic mallet, but be careful that the pulley does not shift on its mountings while you're hammering. Or, you can use a large washer and a x 4 in. bolt, but we suggest the tool. Fig. 42 Use a special tool to remove the damper 6-20 ENGINE MECHANICAL-FORD V8 ENGINES 9. lnstall the retaining bolt and tighten it to 70-90 ft. Ibs. Nm). Squirt a little RTV sealant into the crankshaft keyway to guard against oil seepage. 10. lnstall the drive pulley and tighten the bolts to 22-32 ft. Ibs (30-43 Nm). 11. lnstall the drive belts and make sure that they are adjusted properly. 12. Connect the battery cables. REMOVAL INSTALLATION TE See Figures 43 and This procedure may require engine removal, depending upon your particular boat. If necessary, remove the engine as detailed previously in this section. It is not necessary to remove the front cover in order to remove the oil seal. Open the drain valves and drain the coolant from the block and exhaust manifold. Loosen the alternator and power steering brackets (or the idler pulley) to provide slack, and then remove the drive belts. 2. Drain the oil if you haven't already done so. 3. Remove the alternator and power steering pump bracket bolts. 4. Remove the water circulation pump. The factory actually suggests that you can leave the pump on the cover, but we think removing it facilitates the process--either way will work, so you decide for yourself. 5. Remove the vibration damper and pulley as detailed previously in this section. 6. Remove the few oil pan-to-front cover bolts. Loosen the cover mounting bolts and pry the front cover outward slightly. Insert a razor knife between the cover and block so that it is flush with the inside of the cover and then carefully cut the oil pan gasket at each side of the cover. 7. Remove the cover. 8. If the oil seal needs replacement, position a seal remover tool over the seal and cover. Tighten the thru-bolts to force the puller under the flange and then tighten the puller bolts alternately until the seal is removed. 9. Remove the front cover gasket. To Install: 10. Clean all gasket material from the cover and block mating surfaces with a scraper of putty knife. Be careful not to knock any pieces of gasket into the timing assembly. If you removed the oil seal, coat a new one with Ford Multi-Purpose grease and insert it into the installation tool Position the seal and tool over the end of the crankshaft and push it forward until the seal starts seating itself into the cover. Screw the installation screw with its washer and nut into the end of the crank and then tighten the nut against the washer and sleeve while forcing the seal into the cover. Remove the tool and inspect the front edge of the seal for damage. Fig. 43 Use a sharp knife to cut the oil pan seal 12. Take a new oil pan gasket and cut out a portion of it equal to that which you cut previously when removing the cover. Coat the oil pan mating surface with RTV sealer and carefully position the cut gasket into the flange. While you have the sealer out, run a small bead along the joints where the three (pan, cover and block) surfaces come in contact with one another. Coat the of the oil seal with engine oil. Coat both sides of a new gasket with sealant and then position the gasket onto the engine. lnstall the cover so that all the bolt holes line up and then use an alignment tool P-6019-B) to ensure proper cover-to-block alignment. Coat the mounting bolt threads with Ford Perfect Seal and screw them in finger-tight. Push in on the tool and tighten the cover-to-pan bolts to 9-11 ft. Ibs. (13-14 Nm). Tighten the cover-to-block bolts to 12-18 ft. Ibs. (17-24 Nm). Remove the tool. 14. lnstall the vibration damper and its pulley. 15. lnstall the circulation pump and its pulley (or just the pulley if you chose earlier to leave the pump attached to the cover). Pull the back on. Check their tension adjustment. lnstall the engine if removed. Add oil and start the engine and check for any leaks. Fig. 44 Removing the front cover REMOVAL INSTALLATION CULT See Figures and 47 1. Disconnect the battery cables. 2. Remove the mounting bolts for the alternator and power steering pump brackets. 3. Remove the crankshaft pulley and harmonic balancer as previously detailed in this section. 4. Remove the front cover as previously detailed in this section. 5. Rotate the camshaft slightly so that it creates tension on one side of the timing chain (either side is OK). Find a reference point on the same side of the cylinder block as the side that the timing chain is tight on and then measure from this point to the outer edge of the chain. 6. Rotate the camshaft in the opposite direction until the other side of the chain is tight. Press the inner side of the chain outward until it stops and then measure from your reference point on the cylinder block (obviously, do ENGINE MECHANICAL-FORD V8 ENGINES this from the same side of the chain as did in the to the outer edge of the chain. This is timing chain deflection and it be no more than 0.500 in. If it is more than specification, the chain will require replacement. 7. Look carefully at the camshaft and crankshaft sprockets-you should notice a small indent on the front edge of one of the teeth on each sprocket (it may actually be at the base of the tooth on some sprockets). Bump the engine over until these two marks are in alignment as shown in the illustration--crank mark at and cam mark at a remote starter will work or you can screw the damper bolt back into the crankshaft and turn it with a wrench. 8. Dab a little paint across one of the chain links and the camshaft sprocket. Loosen the camshaft sprocket retaining bolt and remove it along with the fuel pump eccentrics. Grasp the two sprockets at top and bottom, with the chain still attached, and wiggle them off the shafts as an assembly. They should come off readily, but if not, tap the bottom edge lightly with a rubber mallet. Never rotate the crankshaft once the timing chain has been removed. If moved, you'll risk damage to the pistons valve train. To Install: 9. Clean the chain and sprockets in solvent and let them air dry. Check the chain for wear and damage, making sure there are no loose or cracked links. Check the sprockets for cracked or worn teeth. 10. lnstall the timing chain onto the camshaft sprocket so that the paint marks made during removal match up. If they do, and you haven't moved the engine, the timing marks on the two sprockets should also. Hold the in both hands so the chain is hanging down, engage the chain around the crankshaft sprocket making sure that the mark is pointing up, and then slide the assembly onto the two shafts making sure the dowel pin aligns with the hole in the camshaft sprocket. Do not force them! 11. lnstall the two-piece fuel pump eccentric and washer. Install the camshaft bolt and tighten it to 40-45 ft. Ibs. Nm). Never force either of the sprockets onto their shafts or use a hammer. 12. lnstall the front cover, vibration damper and water pump pulley. 13. Install and adjust the drive belts. 14. Reconnect the alternator and power steering brackets. I-Reference Point 45 When checking timing chain deflection, find a reference on the cylinder block and use it for each measurement OIL 47 A good look at the timing chain on the engine CHECKING 2 Locating pins 3-match marks aligned Fig. 46 The two marks on each of the timing sprockets must be in before removing or installing the timing chain See Figures and 50 If the shaft is out of the engine, you can use a micrometer to take the heel-to-lobe measurement and the side-to-side measurement. Subtract the second measurement from the first to get lobe lift. Most times though, the shaft will still be in the cylinder block so perform the following procedure. 6-22 ENGINE MECHANICAL-FORD ENGINES Check each lobe consecutively, from front to back. 11. Remove the installation bolt and install the thrust Tag and disconnect the electrical connectors at the ignition coil. Fig. 48 Use a micrometer when checking the camshaft lift with the shaft out of the engine 2. Remove the cylinder head cover and rocker arms as detailed previously. 3. lnstall a solid push rod into the bore, or use an adapter for ball end rods. Make sure that the rod is seated against the lifter, which is seated on the camshaft lobe. 4. Using a special adaptor, connect a dial indicator so that its tip is positioned on the end of the pushrod-the adaptor should screw onto the end of the rocker stud. 5. Slowly rotate the crankshaft in the direction of engine rotation until the valve lifter is riding on the heel (back side of lobe) of the camshaft lobe. The should be at its lowest point when the lifter is on the heel. A remote starter works well for turning the engine over in this situation. 6. Set the indicator to and then rotate the engine until the is at the highest point of its travel. Camshaft lift should be as detailed in the Engine Specifications chart. 7. Continue rotating the engine until the is back at its lowest position-make sure that the indicator still reads 0. 8. Repeat this procedure for the remaining pushrods. 9. lnstall the rocker arms and adjust the valve clearance. 10. lnstall the cylinder head cover and reconnect the coil leads. REMOVAL INSTALLATION 1. Remove the cylinder head covers and rocker assemblies as previously detailed in this section. Remove the pushrods. 2. Remove the intake manifold. 3. Remove the lifters. Match mark the lifters to their bores and then lift them out and store them in a rack with labels so they can be reinstalled in their original locations. 4. Remove the front cover and timing as previously detailed in this section. 5. Remove the fuel pump and push rod. 6. Remove the thrust platelretainer. 7. Thread the cap bolt back into the camshaft bolt hole and carefully pull the camshaft out of the cylinder block. You may have to wiggle it back and forth a bit, so be sure you don't lean it up or down or else you could damage the bearings. Do not cant the shaft while removing it. To Install: 8. Inspect the camshaft as detailed previously. 9. Coat the camshaft journals with engine oil. Coat the camshaft lobes with engine oil). 10. Carefully insert the shaft into the cylinder block and slide it all the way in. Be very careful not to damage the bearings. 12. lnstall the sprockets, fuel pump eccentrics, timing chain and front cover. 13. Drop the lifters back into their original bores so that they are aligned with the match marks and then install the push rods. 14. lnstall the intake manifold. 15. lnstall the rocker assemblies and the cylinder head covers. REMOVAL INSTALLATION See Figure 51 and 52 Drain the water from the cylinder block and manifold. 2. Remove the fuel line support brackets. Disconnect the fuel line at the carburetorlthrottle body and fuel pump, plug the fitting holes and remove the line. 3. Remove the cylinder head cover and rocker rods as detailed previously in this section. 4. Remove the intake and exhaust manifolds as previously detailed; you can leave the carburetorlthrottle body attached to the intake manifold if you like. 5. If you intend to remove the valve lifters, now is the time to do it. Either way, make sure that you cover the valley of the cylinder block carefully with plenty of rags to prevent dirt from entering any of the passages or settling on any components. 6. Tag and disconnect the spark plug wires at the plugs; move them out of the way. Although not necessary, it's a good idea to remove the plugs themselves also; plug the holes if you do. 7. Remove or relocate any components or connections that may interfere with the removal of an individual cylinder head. 8. Loosen the cylinder head bolts in the reverse order of the illustrated tightening sequence and then carefully lift the head off the block. You may need to persuade it with a rubber mallet-be careful! Set the head down carefully on two support blocks; do not sit it on cement. Its always a good idea to keep a record of which bolts came from which holes. It may sound silly, but on many engines they are different sizes and you wouldn't be the first person to break off a long bolt while tightening it in a short hole. Spend the extra few seconds and do this! To Install: 9. Carefully, and thoroughly, remove all residual head gasket material from the cylinder head and block mating surfaces with a scraper or putty knife. Check that the mating surfaces are free of any nicks or cracks. Make sure there is no dirt or old gasket material in any of the bolt holes. Refer to the Engine Rebuilding section found for complete details on inspection and refurbishing procedures. Dimension A Minus Dimension B Equals The Cam Lobe Lift A Fig. 50 Use a dial indicator when checking the camshaft lift with the shaft in the engine--typical Fig. 49 Measure the camshaft lobe at these two points with the micrometer ENGINE MECHANICAL-FORD V8 ENGINES 6-23 10. Inspect the head bolts on engines. Engines may be equipped with one of two types of bolts. You may reuse all standard head bolts if this is what your engine has, but must replace any "torque-to-yield"bolts as shown in the accompanying illustration. 11. Position a new gasket over the cylinder block dowel pins. Do not use any sealer as the gasket is coated with a lacquer which will provide the proper sealing effect once the engine gets to normal operating temperature the first time. DO NOT use automotive-type steel gaskets. Many times the gasket will be marked, make sure the word UP is facing, you guessed it, 'up', if noted on your gasket. 12. Position the cylinder head over the dowels in the block. lnstall the head bolts finger tight. It never hurts to use new bolts, although it's not necessary (except as noted earlier). 13. Tighten the bolts, a little at a time, in the sequence illustrated, until the proper tightening torque is achieved. engines: the first step should be 50 ft. (68 the second step should be 60 ft. (81 Nm), the third step should be 70 (88-95 Nm). In sequence. engines with standard bolts: the first step should be 65 ft. Ibs. (75-88 Nm), the second step should be 65-72 ft. (88-98 Nm). In sequence. 1994-96 engines with "torque-to-yield bolts: tighten all the bolts, in sequence, to 25-35 (34-47 Next, tighten them to 45-55 ft. Ibs. (61-75 Nm). Finally, tighten all bolts an additional 85"-95" (114 turn). Obviously you will need a meter for these last passes. 1989-93 engines: the first step should be 90 ft. (122 Nm), the second step should be 100 ft. Ibs. (136 Nm), the third step should be 11 2 Ibs. (1 52 Nm). In sequence. 1994-96 engines: the first step, in sequence, should be ft. Ibs. Nm), the second step should be 105-112 Ibs. (143-151 Nm). engines: the first step should be 80 ft. Ibs. (108 Nm), the second step should be 110 ft. Ibs. (149 Nm), the third step should be 135 Ibs. (184 Nm). In sequence, 14. lnstall the rocker assemblies and the cylinder head cover. 15. Install the manifolds and connect the fuel line. Don't forget to remove the fitting plugs. I I Reuse Fig. 51 Make sure to check the head bolts on engines I 16. Install the spark plugs if they were removed and then connect the plug wires. 17. lnstall or connect any other components removed to facilitate getting the head off. 18. Add coolantiwater, connect the battery and check the oil. Start the engine and run it for a while to ensure that everything is operating properly. Keep an eye on the temperature gauge. 19. It never hurts to re-tighten the cylinder head bolts again after 20 hours of operation. REMOVAL INSTALLATION See Figure 53 1. Disconnect the battery cables and then drain all water from the block and manifolds. 2. Drain all waterlcoolant from the cylinder block. 3. Loosen, but do not remove, the pump pulley mounting bolts. 4. Loosen the power steering pump and alternator bracket bolts and swivel them in until you are able to remove the Different engines may have different systems, follow the belt back and loosen the appropriate components. 5. Now you can remove the pump pulley bolts along with the lock washers and clamping ring. Pull off the pulley. 6. Remove the two power steering pump bracket bolts, the brace from the alternator bracket, the retaining bolt and the pump. 7. Disconnect the large water hose at the pump. 8. Tag and disconnect the electrical leads at the alternator and move them out of the way. Remove the bracket bolts and lift off the alternator. 9. Remove the mounting bolts and lift the pump off of the block. There's a good chance you will need to persuade the pump-tap it lightly with a rubber mallet. To Install: 10. Carefully scrape any old gasket material off both mounting surfaces. Inspect the pump for blockage, cracks or any other damage, lnspect the impeller for cracks. Replace either if necessary. 11. Coat both sides of a new gasket with sealant and position on the cylinder block. Make sure that all of the holes are lined up. 12. Position the pump and screw in all bolts except those that attach the alternator and power steering pump brackets. Tighten the bolts to 12-18 ft. Ibs. (17-24 Nm). 13. Reconnect the water hoses and tighten the hose clamps securely. 14. Position the spacer and the bolt behind the rear power steering pump bracket and tighten it securely. Attach the other bracket to the pump and tighten the 2 bolts. 15. lnstall the alternator and tighten the bracket-to-pump bolts to 18-20 ft. Ibs. (24-27 Nm). 16. Attach the steering pump brace to the alternator and tighten the bolt securely. 17. Position the pump pulley and clamping ring on the boss. Screw the mounting bolts and lock washers in and tighten them to 14-20 Ibs. (19-27 Nm). 18. lnstall the drive and adjust them as detailed previously. Start the engine and check the system for leaks Fig. 52 Cylinder head tightening sequence Fig. 53 Removing the water circulating 6-24 ENGINE MECHANICAL-FORD V8 ENGINES Fig. 55 Exploded view of the cylinder engines, all years similar ENGINE MECHANICAL-FORD V8 ENGINES 6-25 TORQUE Alternator Bracket 18-20 24-27 Camshaft Sprocket 55-61 Connecting Rod Cap 19-24 26-33 40-45 54-61 Coolant Temp Sender 18-22 24-30 Crankshaft Main Bearing Cap 60-70 81-95 95-105 129-142 Pulley Bolt 22-32 Cylinder Head Step 1 50 68 Step 2 60 81 Step 3 65-70 8-95 Stretch Bolts Step 25-35 34-47 Step 2 45-55 61-75 Step 3 turn turn 1994-96 Standard Bolts To engine 32-40 43-54 Top nut 40-50 54-60 50-70 68-95 Nut 60-75 81-102 To engine 32-40 43-54 ., Rear Locknut 28-30 38-40 Mount 20-25 27-34 Exhaust Elbow To Manifold 12-14 16-20 12-18 16-24 Exhaust Manifold 20-26 27-35 Exhaust Pipe 20-25 27-34 Flywheel Bellhousing 28-36 38-49 32-40 43-54 Coupler Nut 54-61 Coupler Stud 20-25 27-34 1992-96 14-20 cover 1992: 35-40 ft. Ibs. (47-50) TORQUE SPECIFICATIONS . .- Starter Motor Bolts 24-30 33-41 Bracket 16-19 22-26 Timing Chain Cover To Block 12-18 17-24 To Oil Pan 9-1 1 13-14 Torsional Damper 59 82 Valve Cover 1994-96 36-60 4-6 Vibration Damper 70-90 Water (Circulating) Pump Mounting Bolts 12-18 17-24 Pulley 14-20 19-27 Water Temperature Sender 18-22 24-30 and models: figure is for lower upper manifold 12-18 ft. Ibs. Nm) ENGINE MECHANICAL-FORD V8 ENGINE 6-28 ENGINE MECHANICAL-FORD ENGINES ENGINESPECIFICATIONS - Standard Metric Component (in.) (mm) Valve System (Cont'd) Spring Free Length Exhaust (1989-91) 5. OL (1 992-96) 1.87 1.86 47.5 47.24 1.877 47.68 (1995-96 EFI) 1.87 47.5 (1992-96) 1.877 47.68 Spring Assembled Ht. lntake (1 992-93) 1.66-1.72 1.77-1.80 42.16-43.69 44.96-45.72 (1 994-96) 1.18 27.43 1.78 45.21 (1995-96 EFI) 44.96-45.97 (1992-93) 44.96-45.72 (1994-96) 1.18 27.43 1.78 45.21 (1 995-96 EFI) Exhaust (1989-91) 1.59-1.63 40.39-41.40 1.58-1.61 40.13-40.89 (1989-91) 190-210 Ibs. 1.31 841-941 N Intake (1 995-96 EFI) (1989-91) 1.31 841-941 N 33.27 (1992-93) 195-215 1.15 867-956 N 29.21 (1994-96) 208-228 1.33 925-1014 N 33.78 194-214 1.33 N 33.78 995-96 EFI) Exhaust (1992-96) 195-215 1.15 867-956 N 29.21 190-210 1.31 841-941 N 33.27 Closed Intake (1992-96) 195-215 76-84 1 1.69 867-956 N 340-376 N 29.21 42.92 Exhaust (1992-96) (1992-96) (1 (1992-96) 74-82 74-82 76-84 71-79 71-79 1.78 1.78 1.69 1.60 1.79 329-365 N 329-365 N 340-376 N 318-353 N 318-353 N 45.21 45.21 40.64 45.47 71-79 318-353 N 40.64 Service Limit -10% Length -10% Length Stem Diameter Intake 0.341 6-0.3423 8.677-8.694 Exhaust 0.341 1-0.3418 8.664-8.682 Stem-to-Guide Clear. Production Intake 0.001 0-0.0027 0.0254-0.0686 Exhaust 0.001 5-0.0032 0.038-0.081 Wear Limit 0.0055 0.1397 ENGINE MECHANICAL-FORD V8 ENGINES 6-29 ENGINE SPECIFICATIONS Standard Metric Component (in.) (mm) Camshaft Bearing Clearance Production 0.001-0.003 0.025-0.076 Service Limit 0.006 0.1 52 End Play Production 0.001-0.006 0.025-0.152 Service Limit 0.009 0.229 Journal Diameter 53.95-53.97 Journal Out-of-Round 0.0005 Max 0.0127 Max Lobe Lift Intake 0.285 6.604 Exhaust 0.29 7.061 Loss 0.005 Max 0.127 Max 0.005 Max 0.127 Max Timing Chain Deflection 0.5 12.7 Connecting Rod 6-30 ENGINE MECHANICAL-FORD V8 ENGINES ENGINE SPECIFICATIONS - Standard Metric Component (in.) (mm) Valve system Face Angle 44 deg. 44 deg. Lifter Hydraulic Hydraulic Clearance Production 0.0007-0.0027 0 01 8-0.069 Service Limit 0.005 Max 0 127 Collapsed Gap Production 0.075-0.175 Service Limit 0.1 00-0.150 2.54-3.81 Diameter 22.199-22.213 Push Rod Run Out 0.015 Max 0.381 Max Rocker Arm Lift Ratio Seat Angle 45 deg. 45 deg. Seat Width 0.060-0.080 Spring Free Length 2.06 52.32 Spring Assembled Ht. 1.80-1.83 45.72-46.48 Spring Pressure Open 300-330 Ibs. 1.32 33.74 Closed 87-97 1.82 387-432 46.23 Service Limit -1 0% Length -1 0% Length Stem Diameter Intake 0.3416-0.3423 8.677-8.694 Exhaust 0.341 6-0.3423 8.677-8.694 Stem-to-Guide Clear. Production Intake 0.001 0-0.0027 0.0254-0.0686 Exhaust 0.001 0-0.0027 0.0254-0.0686 Wear Limit 0.0055 0.1397 BUY OR REBUILD? ........................................7-3 CYLINDER HEAD .........................................7-5 ASSEMBLY ............................................. DISASSEMBLY 7-6 INSPECTION 7-7 REFINISHING REPAIRING ................................7.14 DETERMINING ENGINE CONDITION 7-2 COMPRESSION TEST 7-2 OIL PRESSURE TEST ..................................... 7-2 ENGINE BLOCK 7.16 ASSEMBLY 7.21 DISASSEMBLY 7.16 GENERAL INFORMATION 7.16 INSPECTION ............................................7.17 REFINISHING 7-21 ENGINE OVERHAUL 7-3 CLEANING ............................................. 7-3 ........................................ 7-3 REPAIRING DAMAGED THREADS 7-4 TOOLS 7-3 ENGINE PREPARATION .................................... 7-5 ENGINE RECONDITIONING BUY OR REBUILD? ....................................... 7-3 CYLINDER HEAD ........................................7-5 DETERMINING ENGINE CONDITION 7-2 ENGINE BLOCK 7.16 ENGINE OVERHAUL 7-3 ENGINE PREPARATION 7-5 ENGINE START-UP AND BREAK-IN ..........................7.25 ENGINE START-UP AND BREAK-IN 7-25 BREAKING IT 7.25 KEEP IT MAINTAINED 7.25 STARTING THE ENGINE 7.25 7-2 ENGINE OVERHAUL pressure recorded for the highest reading cylinder. For example, if your highest reading cylinder pressure was 150 psi (1034 then 75 percent of Anything that generates heat friction will eventually burn or wear out (for example, a light bulb generates heat, therefore its life span is limited). With this in mind, a running engine generates tremendous amounts of both; friction is encountered by the moving and rotating parts inside the engine and heat is created by friction and combustion of the fuel. However, the engine has systems designed to help reduce the effects of heat and friction and provide added longevity. The oiling system reduces the amount of friction encountered by the moving parts inside the engine, while the cooling system reduces heat created by friction and combustion. If either system is not maintained, a break-down will be inevitable. Therefore, you can see how regular maintenance can affect the service life of your engine. If you do not drain, flush and refill your cooling system at the proper intervals, deposits will begin to accumulate, thereby reducing the amount of heat it can extract from the coolant. The same applies to your oil and filter; if it is not changed often enough it becomes laden with contaminates and is unable to properly lubricate the engine. This increases friction and wear. There are a number of methods for evaluating the condition of your engine. A compression test can reveal the condition of your pistons, piston rings, cylinder bores, head valves and valve seats. An oil pressure test can warn you of possible engine bearing, or oil pump failures. Excessive oil consumption, evidence of oil in the engine air intake area bluish smoke from the exhaust may indicate worn piston rings, worn valve guides valve seals. COMPRESSION TEST See Figure 1 Please refer also to the Maintenance section for details specific to your engine. A noticeable lack of engine power, excessive oil consumption poor fuel mileage measured over an extended period are all indicators of internal engine wear. Worn piston rings, scored or worn cylinder bores, blown head gaskets, sticking or burnt valves, and worn valve seats are all possible culprits. A check of each cylinder's compression will help locate the problem. A screw-in type compression gauge is more accurate than the type you simply hold against the spark plug hole. Although it takes slightly longer to use, it's worth the effort to obtain a more accurate reading. Make sure that the proper amount and viscosity of engine oil is in the crankcase, then ensure the battery is fully charged. 2. Warm-up the engine to normal operating temperature, then shut the engine OFF. 3. Disable the ignition system. 4. Label and disconnect all of the spark plug wires from the plugs. 5. Thoroughly clean the cylinder head area around the spark plug ports, then remove the spark plugs. 6. Set the throttle plate to the fully open (wide-open throttle) position. You can block the throttle linkage open for this, or you can have an assistant operate the throttle lever in the boat. 7. Install a screw-in type compression gauge into the No. 1 spark plug hole until the fitting is snug. Be careful not to cross-thread the spark plug hole. 8. According to the tool manufacturer's instructions, connect a remote starting switch to the starting circuit. 9. With the ignition switch in the OFF position, use the remote starting switch to crank the engine through at least five compression strokes (approximately 5 seconds of cranking) and record the highest reading on the gauge. 10. Repeat the test on each cylinder, cranking the engine approximately the same number of compression strokes time as the first. Compare the highest readings from each cylinder to that of the others. The indicated compression pressures are considered within specifications if the lowest reading cylinder is within 75 percent of the that would be 113 psi (779 So the lowest reading cylinder should be no less than 3 psi (779 11. If a cylinder exhibits an unusually low compression reading, pour a tablespoon of clean engine oil into the cylinder through the spark plug hole and repeat the compression test. If the compression rises after adding oil, it means that the cylinder's piston rings cylinder bore are damaged or worn. If the pressure remains low, the valves may not be seating properly (a valve job is needed), or the head gasket may be blown near that cylinder. compression in any two adjacent cylinders is low, and if the addition of oil doesn't help raise compression, there is past the head gasket. Oil and coolant in the combustion chamber, with blue or constant white smoke from the exhaust, are of this oroblem. However, don't be alarmed by the normal white emitted from exhaust during engine warm-up or from cold weather operation. There may be evidence of water droplets on the engine dipstick oil droplets in the cooling system if a head gasket is blown. Fig. 1 A screw-in type compression gauge is more accurate and easier to use without an assistant OIL PRESSURE TEST Check for proper oil pressure at unit passage with an" externally mounted mechanical oil pressure gauge (as opposed to relying on a factory installed dash-mounted gauge). A tachometer may also be needed, as some specifications may require running the engine at a specific rpm. With the engine cold, locate and remove the oil pressure sending unit. 2. Following the manufacturer's instructions, connect a mechanical oil pressure gauge and, if necessary, a tachometer to the engine. 3. Start the engine and allow it to idle. 4. Check the oil pressure reading when cold and record the number. You may need to run the engine at a specified rpm, so check the specifications. 5. Run the engine until normal operating temperature is reached. 6. Check the oil pressure reading again with the engine hot and record the number. Turn the engine OFF. 7. Compare your hot oil pressure reading to that given in the chart. If the reading is low, check the cold pressure reading against the chart. If the cold pressure is well above the specification, and the hot reading was lower than the specification, you may have the wrong viscosity oil in the engine. Change the oil, making sure to use the proper grade and quantity, then repeat the test. Low oil pressure readings could be attributed to internal component wear, pump related problems, a low oil level, or oil viscosity that is too low. High oil pressure readings could be caused by an overfilled crankcase, too high of an oil viscosity or a faulty pressure relief valve. ENGINE OVERHAUL Now that you have determined that your engine is worn out, you must make some decisions. The question of whether or not an engine is worth rebuilding is largely a subjective matter and one of personal worth. Is the engine a popular one, or is it an obsolete model? Are parts available? Will it get acceptable gas mileage once it is rebuilt? Is the vessel being put into worth keeping? Would it be less expensive to buy a new engine, have your engine rebuilt by a pro, rebuild it yourself or buy a used engine? Or would it be simpler and less expensive to buy another boat? If you have considered all these matters and more, and have still decided to rebuild the engine, then it is time to decide how you will rebuild it. The editorsfeel that most engine machining should be performed by a professional machine shop. Don't think of it as wasting money, rather, as an assurance that the job has been done right the first time. There are many expensive and specialized tools required to perform such tasks as boring and honing an engine block or having a valve job done on a cylinder head. Even inspecting the parts requires expensive micrometers and gauges to properly measure wear and clearances. Also, a machine shop can deliver to you clean, and ready to assemble parts, saving you time and aggravation. Your maximum savings will come from performing the removal, disassembly, assembly and installation of the engine and purchasing or renting only the tools required to perform the above tasks. Depending on the particular circumstances, you may save 40 to 60 percent of the cost doing these yourself. A complete rebuild or overhaul of an engine involves replacing all of the moving parts (pistons, rods, crankshaft, camshaft, etc.) with new ones and machining the non-moving wearing surfaces of the block and heads. Unfortunately, this may not be cost effective. For instance, your crankshaft may have been damaged or worn, but it can be machined undersize for a minimal fee. So, as you can see, you can replace everything inside the engine, but, it is wiser to replace only those parts which are really needed, and, if possible, repair the more expensive ones. Later we will break the engine down into its two main components: the cylinder head and the engine block. We will discuss each component, and the recommended parts to replace during a rebuild on each. Most engine overhaul procedures are fairly standard. In addition to specific parts replacement procedures and specifications for your individual engine, this is also a guide to acceptable rebuilding procedures. Examples of standard rebuilding practice are given and should be used along with specific details concerning your particular engine; which are found in the Engine Mechanical section. Competent and accurate machine shop services will ensure maximum performance, reliability and engine life. In most instances it is more profitable for the do-it-yourself mechanic to remove, clean and inspect the component, buy the necessary parts and deliver these to a shop for actual machine work. Much of the assembly work (crankshaft, bearings, piston rods, and other components) is well within the scope of the do-it-yourself mechanic's tools and abilities. You will have to decide for yourself the depth of involvement you desire in an engine repair or rebuild. TOOLS The tools required for an engine overhaul or parts replacement will depend on the depth of your involvement. With a few exceptions, they will be the tools found in a mechanic's tool kit. More in-depth work will require some or all of the following: A dial indicator (reading in thousandths) mounted on a universal base Micrometers and telescope gauges Jaw and screw-type pullers Scraper Valve spring compressor Ring groove cleaner Piston ring expander and compressor Ridge reamer Cylinder hone or glaze breaker Engine stand The use of most of these tools is illustrated in the procedures. Many can be rented for a one-time use from a local parts jobber or tool supply house specializing in marine or automotive work. Occasionally, the use of special tools is called for. See the information on Special Tools and the Safety Notice in the front of this manual before substituting another tool. OVERHAUL Aluminum has become extremely popular for use in engines, due to its low weight. Observe the following precautions when handling aluminum parts: Never hot tank aluminum parts (the caustic hot tank solution will eat the aluminum. Remove all aluminum parts (identification tag, etc.) from engine parts prior to the tanking. Always coat threads lightly with engine oil or compounds before installation, to prevent seizure. Never over-tighten bolts or spark plugs especially in aluminum threads. When assembling the engine, any parts that will be exposed to frictional contact must be to provide lubrication at initial start-up. Any product specifically formulated for this purpose can be used, but engine oil is not recommended as a pre-lube in most cases. When semi-permanent (locked, but removable) of bolts or nuts is desired, threads should be cleaned and coated with or another similar, commercial non-hardening marine sealant. CLEANING See Figures and 5 Before the engine and its components are inspected, they must be thoroughly cleaned. You will need to remove any engine varnish, oil sludge carbon deposits from all of the components to insure an accurate inspection. A crack in the engine block or cylinder head can easily become overlooked if hidden by a layer of sludge or carbon. Most of the cleaning process can be carried out with common hand tools and readily available solvents or solutions. Carbon deposits can be chipped away using a hammer and a hard wooden chisel. Old gasket material and varnish or sludge can usually be removed using a scraper cleaning solvent. Extremely stubborn deposits may require the use of a power drill with a wire brush. If using a wire brush, use extreme care around any critical machined surfaces (such as the gasket surfaces, bearing saddles, cylinder bores, etc.). Use of a wire brush is NOT RECOMMENDED on any aluminum components. Always follow any safety recommendations given by the manufacturer of the tool solvent. You should always wear eye protection during any cleaning process involving scraping, chipping or spraying of solvents. An alternative to the mess and hassle of cleaning the parts yourself is to drop them off at a local marina or machine shop (or even an automotive garage). They will, more than likely, have the necessary equipment to properly clean all of the parts for a nominal fee. Flg. 2 Use a gasket scraper to remove the old gasket material from the mating surfaces 7-4 ENGINE OVERHAUL Always wear eye protection during any cleaning process involving scraping, chipping or spraying of solvents. Fig. 3 Use a ring expander tool to remove the piston rings Fig. Clean the piston ring grooves using a ring groove cleaner tool, or. .. I Fig. 5 . .. use a piece of an old ring to clean the grooves. Be careful, the ring can be quite sharp Remove any oil galley plugs, freeze plugs pressed-in bearings and carefully wash and degrease all of the engine components including the fasteners and bolts. Small parts such as the valves, springs, etc., should be placed in a metal basket and allowed to soak. Use pipe cleaner type brushes, and clean all passageways in the components. Use a ring expander and remove the rings from the pistons. Clean the piston ring grooves with a special tool or a piece of broken ring. Scrape the carbon off of the top of the piston. You should never use a wire brush on the pistons. After preparing all of the piston assemblies in this manner, wash and degrease them again. Use extreme care when cleaning around the cylinder head valve seats. A mistake or slip may cost you a new seat. When cleaning the cylinder head, remove carbon from the combustion chamber with the valves installed. This will avoid damaging the valve seats. REPAIRING DAMAGED THREADS See Figures 6, and Several methods of repairing damaged threads are available. (shown here), and are among the most widely used. All involve basically the same principle-drilling out stripped threads, tapping the hole and installing a pre-wound insert-making welding, plugging and oversize fasteners unnecessary. Two types of thread repair inserts are usually supplied: a standard type for most inch coarse, inch fine, metric course and metric fine thread sizes and a spark lug type to fit most spark plug port sizes. Consult the individual tool manufacturer's catalog to determine exact applications. Typical thread repair kits will contain a selection of pre-wound threaded inserts, a tap (corresponding to the outside diameter threads of the insert) and an installation tool. Spark plug inserts usually differ because they require a tap equipped with pilot threads and a combined section. Most manufacturers also supply blister-packed thread repair inserts separately in addition to a master kit containing a variety of taps and inserts installation tools. Before attempting to repair a threaded hole, remove any snapped, broken or damaged bolts or studs. Penetrating oil can be used to free frozen threads. The offending item can usually be removed with locking pliers or using a extractor. After the hole is clear, the thread can be as shown in the series of accompanying illustrations and in the kit manufacturer's instructions. BOLT OR SCREW THREADED INSERT I DAMAGED THREADS Fig. 6 Damaged bolt hole threads can be replaced with thread repair inserts ENGINE OVERHAUL 7 Drill out the damaged threads with the specified size bit. Be sure to drill completely through the hole or to the bottom of a blind hole Flg. 8 Using the kit, tap the hole in order to receive the thread insert. Keep the tap well oiled and back it out frequently to clean out the chips Fig. 9 Screw the insert onto the installer tool until the tang engages the slot. Thread the insert into the hole until it is 114112 turn below the top surface, then remove the tool and break off the tang using a punch TANG Fig. 10 Standard thread repair insert (left), and spark plug thread insert To properly rebuild an engine, you must first remove it from the vessel, then disassemble and diagnose it. Ideally you should place your engine on an engine stand. This affords you the best access to the engine components. Follow the manufacturer's directions for using the stand with your particular engine. Remove the flywheel or coupler before installing the engine to the stand. Now that you have the engine on a stand, and assuming that you have drained the oil and waterlcoolant from the engine, it's time to strip it of all but the necessary components. Before you start disassembling the engine, you may want to take a moment to draw some pictures, or labels or containers to mark the locations of various and the bolts studs which fasten them. Modern day engines use a lot of little brackets and clips which hold wiring harnesses and such, and these holders are often mounted on studs bolts that can be easily mixed up. The manufacturer spent a lot of time and money designing your and they wouldn't have wasted any of it by haphazardly placing brackets, clips or fasteners on the boat. If it's present when you disassemble it, put it back when you assemble, you will regret not remembering that little bracket which holds a wire harness out of the path of a rotating part. You should begin by unbolting any accessories still attached to the engine, such as the water pump, power steering pump, alternator, etc. Then, unfasten any manifolds (intake or exhaust) which were not removed during the engine removal procedure. Finally, remove any covers remaining on the engine such as the rocker arm, front or timing cover and oil pan. Some front covers may require the balancer crank pulley to be removed beforehand. The idea is to reduce the engine to the bare necessities (cylinder valve train, engine block, crankshaft, pistons and connecting rods), plus any other 'in block' components such as oil pumps, balance shafts and auxiliary shafts. Finally, remove the cylinder from the engine block and carefully place on a bench. Disassembly instructions for each component follow later. There are two basic types of cylinder heads used on today's engines: Overhead Valve (OHV) and the Overhead Camshaft (OHC). The latter can also be broken down into two subgroups: the Single Overhead Camshaft (SOHC) and the Dual Overhead Camshaft (DOHC). Generally, if there is only a single camshaft on a head, it is just referred to as an OHC head. An engine with an OHV cylinder head is also known as a engine. Most cylinder heads these days are made of an aluminum alloy due to its light weight, durability and heat transfer qualities. However, cast iron was the material of choice in the past, and is still used on many engines today. Whether made from aluminum or iron, all cylinder heads have valves and seats. Most use two valves per cylinder, while the more hi-tech engines will utilize a multi-valve configuration using 3, 4 and even 5 valves per cylinder. When the valve contacts the seat, it does so on precision machined surfaces, which seals the combustion chamber. All cylinder heads have a valve guide for each valve. The guide centers the valve to the seat and allows it to move up and down within it. The clearance between the valve and guide can be critical. Too much clearance and the engine may consume oil, lose vacuum damage the seat. Too little, and the valve can stick in the guide causing the engine to run poorly if at all, and possibly causing severe damage. The last component all cylinder heads have in common are valve springs. The spring holds the valve against its seat. It also returns the valve to this position when the valve has been opened by the valve train or camshaft. The spring is fastened to the valve by a retainer and valve locks (sometimes called keepers). Aluminum heads will also have a valve spring shim to keep the spring from wearing away the aluminum. An ideal method of rebuilding the cylinder head would involve replacing all of the valves, guides, seats, springs, etc. with new ones. However, depending on how the engine was maintained, often this is not necessary. A major cause of valve, guide and seat wear is an improperly tuned engine. An engine that is running too rich, will often wash the lubricating oil out of the guide with gasoline, causing it to wear rapidly. Conversely, an engine which is running too lean will place higher combustion temperatures on the valves and seats allowing them to wear or even burn. Springs fall victim to the operating habits of the individual. A driver who often runs the engine rpm to the will wear out or break the springs faster then one that stays well below it. Unfortunately, 'hours of operation' takes it toll on all of the parts. Generally, guides, springs and seats in a cylinder head can be machined and re-used, saving you money. However, if a valve is burnt, it may be wise to replace all of the valves, since they were all operating in the same environment. The same goes for any other component on the cylinder head. Think of it as an insurance policy against future problems related to that component. Unfortunately, the only way to find out which components need replacing, is to disassemble and carefully check each piece. After the cylinder are disassembled, thoroughly clean all of the components. 7-6 ENGINE OVERHAUL Remove the valve locks from the valve tip retainer. A small DISASSEMBLY magnet may help in removing the locks. OHV Heads 5. Lift the valve tool and all, off of the valve stem. Remove the valve seal from the stem and guide. If the seal is difficult to remove with the valve in place, try removing the valve first, then the seal. Follow the steps below for valve removal. See Figures 11 through 22 7. Position the head to allow access for withdrawing the valve. Before disassembling the cylinder head, you may want to fabricate some . containers to hold the various parts, as some of them can be quite small have mushroomed the valve lock grove tip, causing (such organized will aid in assembly and reduce confusion. Where possible, try to maintain a components' original location; this is especially important if there is not aoina to be anv machine work performed on the comoonents. 1 If already removed the rocker arms shafts, do so now. 8. Remove the valve from the cylinder head. 2. Position the head so that the springs are easily accessed. 9. If equipped, remove the valve spring shim. A small magnetic tool or 3. Use a valve spring compressor tool, and relieve spring tension from screwdriver will aid in removal. the retainer. Repeat Steps 3 though 9 until all of the valves have been removed Due to engine varnish, the retainer may stick to the valve locks. A gentle tap with a hammer may help to break it loose. Fig. 11 When removing a valve spring, use a compressor tool to relieve the tension from the retainer ... 1-Valve spring compressor 2-Rocker arm nut 3-Valve locks Fig. 12 ou may also find a compressor that looks like this Fig. 14 Be careful not to lose the small valve locks (keepers) Fig. 16 Removing an umbrellalpositive type seal I I Fig. 13 A small magnet will help in removal of the valve locks Fig. 15 Remove the valve seal from the valve stem-O-ring type seal shown I Fig. 17 Invert the cylinder head and withdraw the valve from the valve guide bore ENGINE OVERHAUL 7-7 INSPECTION A in. micrometer for the valves A dial indicator or inside diameter gauge for the valve guides Now that all of the cylinder head components are clean, it's time to A spring pressure test gauge inspect them for wear damage. To accurately inspect them, you will If you do not have access to the proper tools, you may want to bring the need some specialized tools: components to a shop that does. Screws Clam Clamp Elbow Grommet \ \ -11 Valve Stem Gasket spring Exhaust Valve Rocker arm stud Head gasket 18 Exploded view of the cylinder head-3.01 4 cylinder engines ENGINE OVERHAUL Rocker Rocker Arm Nut Fig. 19 Exploded view of the cylinder V6 engines Rocker Arm Fig. 20 Exploded view of the cylinder head-5.01 and Ford engines ENGINE OVERHAUL Fig. 21 Exploded view of the cylinder head-5.01 and GM V8 engines 7- OVERHAUL Fig. 22 Exploded view of the cylinder and V8 engines OHC Heads See Figures 23 and 24 Whether it is a single or dual overhead camshaft cylinder head, the disassembly procedure is relatively unchanged. One aspect to pay attention to is careful labeling of the parts on the dual camshaft cylinder head. There will be an intake camshaft and followers as well as an exhaust camshaft and followers and they must be labeled as such. In some cases, the components are identical and could easily be installed incorrectly. DO NOT MIX THEM UP! Determining which is which is very simple; the intake camshaft and components are on the same side of the head as was the intake manifold. Conversely, the exhaust camshaft and components are on the same side of the head as was the exhaust manifold. Fig. 23 Example of a multi-valve cylinder head. Note how it has 2 intake and 2 exhaust valve ports Fig. 24 Exploded view of a valve, seal, spring, retainer and locks from an OHC head ENGINE OVERHAUL 7-11 Cup Type Camshaft Followers + See Figures and 27 Most cylinder heads with cup type camshaft followers will have the valve spring, retainer and locks recessed within the follower's bore. You will need a style valve spring compressor tool, an OHC spring removal tool (or equivalent) and a small magnet to disassemble the head. If not already removed, remove the followers. Mark their positions for assembly. 2. Position the cylinder head to allow use of a style valve spring compressor tool. It is preferred to position the cylinder head gasket surface facing you with the valve springs facing the opposite direction and the head laying horizontal. 3. With the OHC spring removal adapter tool positioned inside of the follower bore, compress the valve spring using the style valve spring compressor. 4. Remove the valve locks. A small magnetic tool or screwdriver will aid in removal. 5. Release the compressor tool and remove the spring assembly. 6. Withdraw the valve from the cylinder head. 7. If equipped, remove the valve seal. Special valve seal removal tools are available. Regular or needlenose type pliers, if used with care, will work just as well. If using ordinary pliers, be sure not to damage the follower bore. The follower and its bore are machined to close tolerances and any damage to the bore will effect this relationship. 8. If equipped, remove the valve spring shim. A small magnetic tool or screwdriver will aid in removal. 9. Repeat Steps 3 through 8 until all of the valves have been removed. ROCKER ARM TYPE CAMSHAFT FOLLOWERS See Figures 28through 36 Most cylinder heads with rocker arm-type camshaft followers are easily disassembled using a standard valve spring compressor. However, certain models may not have enough open space around the spring for the standard tool and may require you to use a C-clamp style compressor tool instead. If not already removed, remove the rocker arms shafts and the camshaft. If applicable, also remove the hydraulic lash adjusters. Mark their positions for assembly. 2. Position the cylinder head to allow access to the valve spring. 3. Use a valve spring compressor tool to relieve the spring tension from the retainer. Due to engine varnish, the retainer may stick to the valve locks. A gentle tap with a hammer may help to break it loose. 4. Remove the valve locks from the valve tip retainer. A small magnet may help in removing the small locks. 5. Lift the valve spring, tool and all, off of the valve stem. 6. If equipped, remove the valve seal. If the seal is difficult to remove with the valve in place, try removing the valve first, then the seal. Follow the steps below for valve removal. 7. Position the head to allow access for withdrawing the valve. Cylinder heads that have seen a lot of miles abuse may have mushroomed the valve lock grove tip, causing difficulty in removal of the valve. If this has happened, use a metal file to carefully remove the high spots around the lock grooves tip. Only file it enough to allow removal. 8. Remove the valve from the cylinder head. 9. If equipped, remove the valve spring shim. A small magnetic tool or screwdriver will aid in removal. 10. Repeat Steps 3 though 9 until all of the valves have been removed. INSPECTION Now that all of the cylinder head components are clean, it's time to inspect them for wear damage. To accurately inspect them, you will need some specialized tools: A 0-1 in. micrometer for the valves A dial indicator or inside diameter gauge for the valve guides A spring pressure test gauge If you do not have access to the proper tools, you may want to bring the components to a shop that does. Valves See Figures 37and 38 DERA The first thing to inspect are the valve he margin and for cracks, excessive wear or Ihe the best place to look for burning. It should have a squared edge with an even width all around the diameter. When a valve burns, the margin will look melted and the edges rounded. Also inspect the valve head for any signs of tulipping. This will show as a lifting of the edges or dishing in the center of the head and will usually not occur to all of the valves. All of the heads should look the same, any that seem dished more than others are probably bad. Next, inspect the valve lock grooves and valve tips. Check for any burrs around the lock grooves, especially if you had to file them to remove the valve. Valve tips should appear flat, although slight rounding with high mileage engines is normal. Slightly worn valve tips will need to be machined flat. Last, measure the valve stem diameter with the micrometer. Measure the area that rides within the guide, especially towards the tip where most of the wear occurs. Take measurements along its length and compare them to each other. Wear should be even along the length with little to no taper. If no minimum diameter is given in the specifications, then the stem should not read more than 0.001 in. below the unworn area of the valve stem. Any valves that fail these inspections should be replaced. I I Fig. 27 Position the OHC spring tool in the an OHC spring removal tool (center) for cup heads retain the camshaft using bolt-on Fig. 25 C-clamp type spring compressor and Fig. 26 Most cup type follower cylinder follower bore, then compress the spring with a C-clamp type tool type followers bearing caps 7-12 ENGINE OVERHAUL Fig. 28 Example of the shaft mounted rocker arms on some OHC heads Fig. 29 Another example of the rocker arm type OHC head. This model uses a follower under the camshaft Fig. 30 Before the camshaft can be removed, all of the followers must first be removed . . . Fig. 31 . . . then the camshaft can be Fig. 32 Compress the valve spring . . . Fig. 33 . . . then remove the valve locks from removed by sliding it out (shown), or the valve stem and spring retainer unbolting a bearing cap (not shown) Fig. 34 Remove the valve spring and retainer Fig. 35 Remove the valve seal from the from the cylinder head guide. Some gentle prying or pliers may help to remove stubborn ones Fig. 38 Use a micrometer to check the valve stem diameter Fig. 36 All aluminum and some cast iron heads will have these valve spring shims. Remove all of them as well Fig. 37 Valve stems may be rolled on a flat surface to check for bends ENGINE OVERHAUL 7-13 Springs, Retainers and Valve Locks See Figures 39 and 40 The first thing to check is the most obvious, broken springs. Next check the free length and squareness of each spring. applicable, insure to distinguish between intake and exhaust springs. Use a ruler carpenter's square to measure the length. A carpenter's square should be used to check the springs for squareness. If a spring pressure test gauge is available, check each springs rating and compare to the specifications chart. Check the readings against the specifications given. Any springs that fail these inspections should be replaced. The spring retainers rarely need replacing, however they should still be checked as a precaution. Inspect the spring mating surface and the valve lock retention area for any signs of excessive wear. Also check for any signs of cracking. Replace any retainers that are questionable. Valve locks should be for excessive wear on the outside contact area as well as on the inner notched surface. Anv locks which appear worn or broken and its respective valve should be replaced. Fig. 39 Use a caliper to check the valve spring free-length Fig. 41 A dial gauge may be used to check valve stem-to-guide Fig. 40 Check the valve spring for squareness on a flat surface; a carpenter's square can be used Cylinder Head There are several things to check on the cylinder head: guides, seats, cylinder head surface flatness, cracks and physical damage. Valve Guides See Figure 41 Now that you know the valves are good, you can use them to check the guides, although a new valve, if available, is preferred. Before you measure anything, look at the guides carefully and inspect them for any cracks, chips or breakage. Also if the is a removable stvle in most aluminum heads), them for looseness or evidence of movement. All of the guides should appear to be at the same height from the spring seat. If any seem lower (or higher) from another, the guide has moved. Mount a dial indicator onto the spring side of the cylinder head. Lightly oil the valve stem and insert it into the cylinder head. Position the dial indicator against the valve stem near the tip and zero the gauge. Grasp the valve stem and wiggle towards and away from the dial indicator and observe the readings. Mount the dial indicator 90 degrees from the initial point and zero the gauge and again take a reading. Compare the two readings for a out of round condition. Check the readings against the specifications given. An Inside Diameter gauge designed for valve guides will give you an accurate valve guide bore measurement. If the I.D. gauge is used, compare the readings with the specifications given. Any guides that fail these inspections should be replaced or machined. clearance; read the gauge while moving the valve stem Valve Seats A visual inspection of the valve seats should show a slightly worn and pitted surface where the valve face contacts the seat. the seat carefully for severe pitting or cracks. Also, a seat that is worn will be recessed into the cylinder head. A severely worn or recessed seat may need to be replaced. All cracked seats must be replaced. A seat concentricity gauge, if available, should be used to check the seat run-out. If run-out exceeds specifications the seat must be machined (if no specification is given use 0.002 in. or Cylinder Head Surface Flatness See Figures 42 and 43 After you have cleaned the gasket surface of the cylinder head of any old gasket material, check the head for flatness. Place a straightedge across the gasket surface. Using feeler gauges, determine the clearance at the center of the straightedge and across the cylinder head at several points. Check along the centerline and diagonally on the head surface. If the exceeds 0.003 in. within a 6.0 in. span, or 0.006 in. over the total length of the head, the cylinder head must be resurfaced. After resurfacing the heads of a V-type engine, the intake manifold flange surface should be checked, and if necessary, milled proportionally to allow for the change in its mounting 7-14 ENGINE OVERHAUL surface using a straightedge and feeler gauge 'racks And Physical Damage Generally, cracks are limited to the combustion chamber, however, it is not uncommon for the head to crack in a spark plug hole, port, outside of the head or in the valve springlrocker arm area. The first area to inspect is always the hottest: the exhaust seatlport area. A visual inspection should be performed, but just because you don't see a crack does not mean it is not there. Some more reliable methods for inspecting for cracks include a magnetic process or a dye penetrant. is used only on ferrous metal (cast iron) heads. uses a spray on fluorescent mixture along with a black light to reveal the cracks. It is strongly recommended to have your cylinder head checked professionally for cracks, especially if the engine was known to have overheated leaked or consumed coolant. Contact a local shop for availability and pricing of these services. Physical damage is usually very evident. For example, a broken mounting ear from dropping the head or a bent or broken stud bolt. All of these defects should be fixed or, if not repairable, the head should be replaced. Camshaft and Followers Inspect the and followers as described earlier. REFINISHING & REPAIRING LED Many of the procedures for and repairing head must be bv a the inspected part is not worn, can be performed inexpensively. However, you spent a lot of time and effort so far; why risk trying to save a couple bucks if you might have to do it all over again? Valves L LED Any valves that were not replaced should be and the ground flat. Unless you have access to a valve grinding machine, this should be done by a machine shop. If the valves are in extremely good condition, as well as the valve seats and guides, they may be lapped in without performing machine work. It is a recommended practice to lap the valves even after machine work has been performed new valves have been purchased. This insures a positive seal between the valve and seat. Lapping The Valves Before lapping the valves to the seats, read the rest of the cylinder head procedure to insure that any related parts are in acceptable enough condition to continue. Fig 42 Check the head for flatness across the center of the head Fig. 43 Checks should also be made along both diagonals of the head surface Before any valve seat machining lapping can be performed, the guides must be within factory recommended specifications. I.Invert the cylinder head. 2. Lightly lubricate the valve stems and insert them into the cylinder head in their numbered order. 3. Raise the valve from the seat and apply a small amount of fine lapping compound to the seat. 4. Moisten the suction head of a hand-lapping tool and attach it to the head of the valve. 5. Rotate the tool between the palms of both hands, changing the position of the valve on the valve seat and lifting the tool often to prevent grooving. 6. Lap the valve until a smooth, polished circle is evident on the valve and seat. 7. Remove the tool and the valve. Wipe away all traces of the grinding compound and store the valve to maintain its lapped location. Do not get the valves out of order after they have been lapped. They must be put back with the same valve seat with which they were lapped. Springs, Retainers and Valve Locks There is no repair or refinishing possible with the springs, retainers and valve locks. If they are found to be worn or defective, they must be replaced with new (or known good) parts. Cylinder Head Most refinishing procedures dealing with the cylinder head be performed by a machine shop. Read the procedures below and review your inspection data to determine whether or not machining is necessary. Valve Guide any machining or replacements are made to the valve guides, the seats must be machined. Unless the valve guides need machining or replacing, the only service to perform is to thoroughly clean them of any dirt or oil residue. There are only two types of valve guides used on automobile engines: the replaceable-type (all aluminum heads) and the cast-in integral-type (most cast iron heads). There are four recommended methods for repairing worn guides. ENGINE OVERHAUL Inserts a process metal and thereby clearance, a true center, and control It the least way of the valve However, not the best, and some cases, a knurled valve guide not stand up for more than a short It a and precrsron tools to proper clearances It would not be cost to purchase these tools, unless you plan on several of the same head a guide the to accept a bronze One style the whrch Installed rnto a threaded guide Another the thrn-walled where the reamed overslze to accept a insert After the a tool then run through the to expand the Insert, to the The Insert then reamed to the standard srze for proper valve clearance for overslze valves restores normal clearances and provrdes a true valve seat Most type can be reamed to accept an valve an overslze stem The cost factor for can become as you need to purchase the reamer and new, overslze stem valves for all gurdes whrch were reamed are generally 003 to 030 076 to 015 the most common To replace type valve they must be out, then reamed to accept replacement must be done on a allow centerrng and off of the valve seat or a serious seat may occur makrng to properly the seat Replaceable-type gurdes are pressed the head A hammer and a stepped or punch may be used to and remove the Before the measure the on the spring of the head and record for Use the stepped to hammer out the old from the chamber of the head When installing, determine whether or not the also seals a water jacket the head, and does, use the recommended sealing agent If there no water jacket, grease the valve and bore Use the stepped and hammer the new the head from the of the head A stack of washers the same as the measured may help the rnstallatron process Valve Seats Before any valve seat machining can be performed, the guides must be within factory recommended specifications. If any machining or replacements were made to the valve guides, the seats must be machined. If the seats are in good condition, the valves can be lapped to the seats, and the cylinder head assembled. See the valves procedures for instructions on lapping. If the valve seats are worn, cracked or damaged, they must be serviced by a machine shop. The valve seat must be perfectly centered to the valve guide, which requires very accurate machining. Cylinder Head Surface If the cylinder head is warped, it must be machined flat. If the is extremely severe, the head may need to be replaced. In some instances, it may be possible to straighten a warped head enough to allow machining. In either case, contact a professional shop for service. Cracks And Physical Damage Certain cracks can be repaired in both cast iron and aluminum heads. For cast iron, a tapered threaded insert is installed along the length of the crack. Aluminum can also use the tapered inserts; however welding is the preferred method. Some physical damage can be repaired through brazing or welding. Contact a machine shop to get expert advice for your particular dilemma. Any OHC cylinder head that shows excessive should have the bearing journals align bored after the cylinder head has been resurfaced. Failure to align bore the camshaft bearing journals could result in severe engine damage including but not limited to: valve and piston damage, connecting rod damage, camshaft crankshaft breakaae. ASSEMBLY DERATE The first step for any assembly job is to have a clean area in which to work. Next, thoroughly clean all of the parts and components that are to be assembled. Finally, place all of the components onto a suitable work space and, if necessary, arrange the parts to their respective positions. OHV Engines Lightly lubricate the valve stems and insert all of the valves into the cylinder head. If possible, maintain their original locations. 2. If equipped, install any valve spring shims which were removed. 3. If equipped, install the new valve seals, keeping the following in mind: If the valve seal presses over the guide, lightly lubricate the outer guide surfaces. If the seal is an O-ring type, it is installed just after compressing the spring but before the valve locks. 4. Place the valve spring and retainer the stem. 5. Position the spring compressor tool and compress the spring. 6. Assemble the valve locks to the stem. 7. Relieve the spring pressure slowly and insure that neither valve lock becomes dislodged by the retainer. 8. Remove the spring compressor tool. 9. Repeat Steps 2 through 8 until all of the springs have been installed. OHC Engines See Figure 44 CUP TYPE CAMSHAFT FOLLOWERS To install the springs, retainers and valve locks on heads which have these components recessed into the camshaft follower's bore, you will need a small screwdriver-type tool, some clean white grease and a lot of patience. You will also need the C-clamp style spring compressor and the OHC tool used to disassemble the head. 1. Lightly lubricate the valve stems and insert all of the valves into the cylinder head. If possible, maintain their original locations. 2. If equipped, install any valve spring shims which were removed. 3. If equipped, install the new valve seals, keeping the following in mind: If the valve seal presses over the guide, lightly lubricate the outer guide surfaces. If the seal is an O-ring type, it is installed just after compressing the spring but before the valve locks. 4. Place the valve spring and retainer over the stem. 5. Position the spring compressor and the OHC tool, then compress the spring. 6. Using a small screwdriver as a spatula, fill the valve stem side of the lock with white grease. Use the excess grease on the screwdriver to fasten the lock to the driver. 7. Carefully install the valve lock, which is stuck to the end of the screwdriver, to the valve stem then press on it with the screwdriver until the grease squeezes out. The valve lock should now be stuck to the stem. 8. Repeat Steps 6 and 7 for the remaining valve lock. 9. Relieve the spring pressure slowly and insure that neither valve lock becomes dislodged by the retainer. 10. Remove the spring compressor tool. 11. Repeat Steps 2 through 10 until all of the springs have been installed. 12. Install the followers, and any other components that were removed for disassembly. ROCKER ARM TYPE CAMSHAFT FOLLOWERS Lightly lubricate the valve sterns and insert all of the valves into the cylinder head. If possible, maintain their original locations. 2. If equipped, install any valve spring shims which were removed. 3. equipped, install the new valve seals, keeping the following in mind: If the valve seal presses over the guide, lightly lubricate the outer guide surfaces. the seal is an O-ring type, it is installed just after compressing the spring but before the valve locks. 4. Place the valve spring and retainer over the stem. 5. Position the spring compressor tool and compress the spring. 6. Assemble the valve locks to the stem. 7. Relieve the spring pressure slowly and insure that neither valve lock becomes dislodged by the retainer. 8. Remove the spring compressor tool. Repeat Steps 2 through 8 until all of the springs have been installed. 10. Install the rockers, shafts and any other components that were removed for disassembly. GENERAL INFORMATION A thorough overhaul or rebuild of an engine block would include replacing the pistons, rings, bearings, timing assembly and oil pump. For OHV engines also include a new camshaft and lifters. The block would then have the cylinders bored and honed oversize (or if using removable cylinder sleeves, new sleeves installed) and the crankshaft would be cut undersize to provide new wearing surfaces and perfect clearances. However, your particular engine may not have everything worn out. What if only the piston rings have worn out and the clearances on everything else are still within factory specifications? Well, you could just replace the rings and put it back together, but this would be a very rare example. Chances are, if one component in your engine is worn, other components are sure to follow, and soon. At the very least, you should always replace the rings, bearings and oil pump. This is what is commonly called a "freshen up". Because the top piston ring does not travel to the very top of the cylinder, a ridge is built up between the end of the travel and the top of the cylinder bore. Pushing the piston and connecting rod assembly past the ridge can be difficult, and damage to the piston ring lands could occur. If the ridge is not removed before installing a new piston or not removed at all, piston ring breakage and piston damage may occur. It is alwavs recommended that remove before the piston and connecting rod assemblies. If know that new pistons are going to be installed and the engine block will be bored oversize, you may be able to forego this step. However, some ridges may actually prevent the assemblies from being removed, necessitating its removal. There are several different types of ridge reamers on the market, none of which are inexpensive. Unless a great deal of engine rebuilding is anticipated, borrow or rent a reamer. Turn the crankshaft until the piston is at the bottom of its travel. 2. Cover the head of the piston with a rag. 3. Follow the tool manufacturers instructions and cut away the ridge, exercising extreme care to avoid cutting too deeply. 4. Remove the ridge reamer, the rag and as many of the cuttings as possible. Continue until all of the cylinder ridges have been removed. DISASSEMBLY CULT See Figures 47 48 49 and 50 The engine disassembly instructions following assume that you have the engine mounted on an engine stand. If not, it is easiest to disassemble the engine on a bench or the floor with it resting on the bell housing or transmission mounting surface. You must be able to access the connecting rod fasteners and turn the crankshaft during disassembly. Also, all engine covers (timing, front, side, oil pan, whatever) should have already been removed. Engines which are seized or locked up may not be able to be completely disassembled, and a core (salvage yard) engine should be purchased. On OHV engines, if not done during the cylinder head removal, remove the and lifters, keeping them in order for assembly. Remove the timing gears timing chain assembly, then remove the oil pump drive assembly and withdraw the camshaft from the engine block. Remove the oil pick-up and pump assembly. If equipped, remove any balance or auxiliary shafts. If necessary, remove the cylinder ridge from the top of the bore. See the cylinder ridge removal procedure. On OHC engines, if not done during the cylinder head removal, remove the timing assembly. Remove the oil pick-up and pump assembly and, if necessary, the pump drive. If equipped, remove any balance or auxiliary shafts. If necessary, remove the cylinder ridge from the top of the bore. See the cylinder ridge removal procedure. Rotate the engine over so that the crankshaft is exposed. Use a number punch or scribe and mark each connecting rod with its respective cylinder number. The cylinder closest to the front of the engine is always number However, depending on the engine placement, the front of the engine could either be the flywheel or end. Generally the front of the engine faces the bow. Use a number punch or scribe and also mark the main bearing caps from front to rear with the front most cap being number 1 (if there are five caps, mark them 1 through 5, front to rear). Take special care when pushing the connecting rod up from the crankshaft because the sharp threads of the rod will score the crankshaft journal. Insure that special plastic caps are installed over them, or cut two pieces of rubber hose to do the same. Fig. 45 Place rubber hose over the connecting rod studs to protect the crankshaft and cvlinder bores from Once assembled, check the valve clearance and correct as ENGINE OVERHAUL 7-17 Fig. 46 Carefully tap the piston out of the bore using a wooden dowel Aaain, rotate the enaine, this time to the number one cvlinder surface) the crankshaft until the number one is at the bottom of its travel, this should allow the maximum access to its connecting rod. Remove the number one connecting rods fasteners and cap and place two of rubber hose over the rod to protect the crankshaft from damage. Using a sturdy wooden dowel and a hammer, push the connecting rod up about 1 in. from the crankshaft and remove the upper bearing insert. Continue pushing or tapping the connecting rod up until the piston rings are out of the cylinder bore. Remove the piston and rod by hand, put the upper half of the bearing insert back into the rod, install the cap with its bearing insert installed, and hand-tighten the cap fasteners. If the parts are kept in order in this manner, they will not get lost and you will be able to tell which bearings came form what cylinder if any problems are discovered and diagnosis is necessary. Remove all the other piston assemblies in the same manner. On V-style engines, remove all of the pistons from one bank, then reposition the engine with the other cylinder bank head surface up, and remove that banks piston assemblies. The only remaining component in the engine block should now be the crankshaft. Loosen the main bearing caps evenly until the fasteners can be turned by hand, then remove them and the caps. Remove the crankshaft from the engine block. Thoroughly clean all of the components. INSPECTION Now that the engine block and all of its components are clean; it's time to inspect them for wear damage. To accurately inspect them, you will need some specialized tools: Two or three separate micrometers to measure the pistons and crankshaft journals A dial indicator Telescoping gauges for the cylinder bores A rod alignment fixture to check for bent connecting rods If you do not have access to the proper tools, you may want to bring the components to a shop that does. Generally, you shouldn't expect cracks in the engine block or its components unless it was known to leak, consume or mix fluids, it was severely overheated, or there was evidence of bad bearings crankshaft damage. A visual inspection should be performed on all of the components, but just because you don't see a crack does not mean it is not there. Some more reliable methods for inspecting for cracks include a magnetic process or a dye penetrant. is used only on ferrous metal (cast iron). uses a spray on fluorescent mixture along with a black light to reveal the cracks. It is strongly recommended to have your engine block checked professionally for cracks, especially if the engine was known to have overheated leaked or consumed coolant. Contact a local shop for availability and pricing of these services. Engine Block LED Engine Block Bearing Alignment Remove the main bearing caps and, if still installed, the main bearing inserts. Inspect all of the main bearing saddles and caps for damage, burrs or high spots. If damage is found, and it is caused from a spun main bearing, the block will need to be align-bored or, if severe enough, replacement. Any burrs or high spots should be carefully removed with a metal file. Place a straightedge on the bearing saddles, in the engine block, along the centerline of the crankshaft. If any clearance exists between the straightedge and the saddles, the block must be align-bored. Align-boring consists of machining the main bearing saddles and caps by means of a flycutter that runs through the bearing saddles. Deck Flatness The top of the engine block where the cylinder head mounts is called the deck. Insure that the deck surface is clean of dirt, carbon deposits and old gasket material. Place a straightedge across the surface of the deck along its centerline and, using feeler gauges, check the clearance along several points. Repeat the checking procedure with the straightedge placed along both diagonals of the deck surface. If the reading exceeds 0.003 in. within a 6.0 in. span, or 0.006 in, over the total length of the deck, it must be machined. Always check the Specification chart for your specific engine. Cylinder Bores See Figure 51 The cylinder bores house the pistons and are slightly larger than the pistons themselves. A common piston-to-bore clearance is 0.0015-0.0025 in. (0.0381 Refer to the Specification chart for your specific engine. Inspect and measure the cylinder bores. The bore should be checked for out-of-roundness, taper and size, The results of this inspection will determine whether the cylinder can be used in its existing size and condition, or a to the oversize is required (or in the case of removable sleeves, have replacements installed). The amount of cylinder wall wear is always greater at the top of the cylinder than at the bottom. This wear is known as taper. Any cylinder that has a taper of 0.0012 in. or more, must be re-bored. Measurements are taken at a number of positions in each cylinder: at the top, middle and bottom and at two points at each position; that is, at a point 90 degrees from the crankshaft centerline, as well as a point parallel to the crankshaft centerline. The measurements are made with either a special dial indicator or a telescopic gauge and micrometer. If the necessary precision tools to check the bore are not available, take the block to a machine shop and have them mike it. Also if you don't have the tools to check the cylinder bores, chances are you will not have the necessary devices to check the pistons, connecting rods and crankshaft. Take these components with you and save yourself an extra trip. For our procedures, we will use a telescopic gauge and a micrometer. You will need one of each, with a measuring range which covers your cylinder bore size. Fig. 47 Exploded view of the cylinder block-3-014 cylinder engines Piston w Strip Fig. 48 Exploded view of the cylinder V6 engines Fig. 50 Exploded view of the cylinder block-Ford V8engines Pistons 8 Rings Fig. 49 Exploded view of the cylinder block-GM V8engines 7-20 ENGINE OVERHAUL Fig. 51 Use a telescoping gauge to measure the cylinder bore diameter-take several readings within the same bore I Position the telescopic gauge in the cylinder bore, loosen the gauges lock and allow it to expand. Your first two readings will be at the top of the cylinder bore, then proceed to the middle and finally the bottom, making a total of six measurements. 2. Hold the gauge square in the bore, 90 degrees from the crankshaft centerline, and gently tighten the lock. Tilt the gauge back to remove it from the bore. 3. Measure the gauge with the micrometer and record the reading. 4. Again, hold the gauge square in the bore, this time parallel to the crankshaft centerline, and gently tighten the lock. Again, you will tilt the gauge back to remove it from the bore. 5. Measure the gauge with the micrometer and record this reading. The difference between these two readings is the out-of-round measurement of the cylinder. 6. Repeat Steps 1 through 5, each time going to the next lower position, until you reach the bottom of the cylinder. Then go to the next cylinder, and continue until all of the cylinders have been measured. The difference between these measurements will tell you all about the wear in your cylinders. The measurements which were taken 90 degrees from the crankshaft centerline will always reflect the most wear. That is because at this position is where the engine power presses the piston against the cylinder bore the hardest. This is known as thrust wear. Take your top, 90 degree measurement and compare it to your bottom, 90 degree measurement. The difference between them is the taper. When you measure your pistons, you will compare these readings to your piston sizes and determine piston-to-wall clearance. Crankshaft LED Inspect the crankshaft for visible signs of wear or damage. All of the journals should be perfectly round and smooth. Slight scores are normal for a used crankshaft, but you should hardly feel them with your fingernail. When measuring the crankshaft with a micrometer, you will take readings at the front and rear of each journal, then turn the micrometer 90 degrees and take two more readings, front and rear. The difference between the rear readings is the journal taper and the first-to-90 degree reading is the out-of-round measurement. Generally, there should be no taper or roundness found, however, up to 0.0005 in. for either can be overlooked. Also, the readings should fall within the factory specifications for journal diameters. If the crankshaft journals fall within specifications, it is recommended that it be polished before being returned to service. Polishing the crankshaft insures that any minor burrs or high spots are smoothed, thereby reducing the chance of scoring the new bearings. Pistons and Connecting Rods Pistons LED See Figure 52 The piston should be visually inspected for any signs of cracking or burning (caused by hot spots or detonation), and scuffing or excessive wear on the skirts. The wrist pin attaches the piston to the connecting rod. The piston should move freely on the wrist pin, both sliding and pivoting. Grasp the connecting rod securely, or mount it in a vise, and try to rock the piston back and forth along the centerline of the wrist pin. There should not be any excessive play evident between the piston and the pin. If there are C-clips retaining the pin in the piston then you have wrist pin bushings in the rods. There should not be any excessive play between the wrist pin and the rod bushing. Normal clearance for the wrist pin is approx. 0.001-0.002 in. mm). Please refer to the Specification chart for your specific engine. of the measurement obtained earlier. difference readings is the piston-to-wall clearance. If the clearance is within specifications, the piston may be used as is. If the piston is out of specification, but the bore is not, you will need a new piston, If both are out of specification, you will need the cylinder and oversize pistons installed. Generally if two or more are out of it is best to the entire block and purchase a complete set of oversize pistons. I I Fig. 52 Measure the piston's outer diameter, perpendicular to the wrist pin, with a micrometer I Connecting Rod the rod checked for a connecting rod is bent, it will unevenly and piston, as well as place stress on these components. Any bent or twisted connecting rods must be replaced. If the rods are straight and the wrist pin clearance is within specifications, then only the bearing end of the rod need be checked. Place the connecting rod into a vice, with the bearing inserts in place, install the cap to the rod and torque the fasteners to specifications. Use a telescoping gauge and carefully measure the inside diameter of the bearings. Compare this reading to the rods original crankshaft journal diameter measurement. The difference is the oil clearance. If the oil clearance is not within specifications, install new bearings in the rod and take another measurement. If the clearance is still out of specifications, and the crankshaft is not, the rod will need to be reconditioned by a machine shop. You can also use to check the bearing clearances. The assembling procedure has complete instructions on its use. ENGINE OVERHAUL Camshaft lnspect the camshaft and as described earlier. Bearings All of the engine bearings should be visually inspected for wear damage. The bearing should look evenly worn all around with no deep scores or pits. If the bearing is severely worn, scored, pitted or heat blued, then the bearing, and the components that use it, should be brought to a machine shop for inspection. Full-circle bearings (used on most camshafts, auxiliary shafts, balance shafts, etc.) require specialized tools for removal and installation, and should be brought to a machine shop for service. Oil Pump The oil pump is responsible for providing constant lubrication to the whole engine and so it is recommended that a new oil pump be installed when rebuilding the engine. Completely disassemble the oil pump and thoroughly clean all of the components. lnspect the oil pump gears and housing for wear damage. lnsure that the pressure relief valve operates properly and there is no binding or sticking due to varnish or debris. If all of the parts are in proper working condition, lubricate the gears and relief valve, and assemble the REFINISHING See Figure 53 Almost all engine block refinishing must be performed by a machine shop. If the cylinders are not to be re-bored, then the cylinder glaze can be removed with a ball hone. When removing cylinder glaze with a ball hone, use a light or penetrating type oil to lubricate the hone. Do not allow the hone to run dry as this may cause excessive scoring of the cylinder bores and wear on the hone. If new pistons are required, they will need to be installed to the connecting rods. This should be performed by a machine shop as the pistons must be installed in the correct relationship to the rod or engine damage can occur. Pistons and Connecting Rods See Figure 54 Because of the tools necessary, only pistons with the wrist by C-clips are serviceable by the or technician. Press fit pistons require Dresses heaters to the connectina rod and should be performed by a machine shop. Flg. 53 Use a ball type cylinder hone to remove any glaze and provide a new surface for seating the piston rings Fig. 54 Most pistons are marked to indicate positioning in the engine (usually a mark means the side facing the front) All pistons will have a mark indicating the direction to the front of the engine and the must be installed into the engine in that manner. Usually it is a notch or arrow on the top of the piston, or it may be the letter F cast or stamped into the piston. C-Clip Type Pistons Note the location of the forward mark on the piston and mark the connecting rod in relation. 2. Remove the C-clips from the piston and withdraw the wrist pin. Varnish build-up or C-clip groove burrs may increase the difficulty of removing the wrist pin. If necessary, use a punch or drift to carefully tap the wrist pin out. lnsure that the wrist pin bushing in the connecting rod is usable and lubricate it with assembly lube. 4. Remove the wrist pin from the new piston and lubricate the pin bores on the piston. 5. Align the forward marks on the piston and the connecting rod and install the wrist pin. 6. The new C-clips will have a flat and a rounded side to them. Install both C-clips with the flat side facing out. 7. Repeat all of the steps for each piston being replaced. ASSEMBLY Before you begin assembling the engine, first give yourself a clean, dirt free work area. Next, clean every engine component again. The key to a good assembly is cleanliness. Mount the engine block into the engine stand and wash it one last time using water and detergent (dishwashing detergent works well). While washing it, scrub the cylinder bores with a soft bristle brush and thoroughly clean all of the oil passages. Completely dry the engine and spray the entire assemblv down with an anti-rust solution such as or similar Take a dean lint-free rag and wipe up any excess anti-rust solution the bores, bearing saddles, etc. Repeat the final cleaning process on the crankshaft. Replace any freeze or oil galley plugs which were removed during disassembly. Crankshaft CULT See Figures and 59 Remove the main bearing inserts from the block and bearing caps. If the crankshaft main bearing journals have been refinished to a definite undersize, install the correct undersize bearing. Be sure that the bearing inserts and bearing bores are clean. Foreign material under inserts will distort bearing and cause failure. 3. Place the upper main bearing inserts in bores with tang in slot. The oil holes in the bearing inserts must be aligned with the oil holes in the cylinder block. 4. lnstall the lower main bearing inserts in bearing caps. 5. Clean the mating surfaces of block and rear main bearing cap. 6. Carefully lower the crankshaft into place. Be careful not to damage bearing surfaces. 7. Check the clearance of each main bearing by using the following procedure: a. Place a piece of or its equivalent, on bearing surface across full width of bearing cap and about 114 in. off center. b. lnstall cap and tighten bolts to specifications, Do not turn crankshaft while is in place. c. Remove the cap. Using the supplied scale, check width of at widest point to get maximum clearance. Difference between readings is taper of journal. d. clearance exceeds specified limits, try a 0.001 in. or 0.002 in. undersize bearing in combination with the standard bearing. Bearing clearance must be within specified limits. If standard and 0.002 in. undersize bearing does not bring clearance within desired limits, refinish crankshaft journal, then install undersize bearings. Fig. 55 Apply a strip of gauging material to the bearing journal, then install and torque the cap 8. Install the rear main seal. 9. After the bearings have been fitted, apply a light coat of engine oil to the journals and bearings, Install the rear main bearing cap. Install all bearing caps except the thrust bearing cap. Be sure that main bearing caps are installed in original locations. Tighten the bearing cap bolts to specifications. 10. lnstall the thrust bearing cap with bolts finger-tight. Pry the crankshaft forward against the thrust surface of upper half of bearing. 12. Hold the crankshaft forward and pry the thrust bearing cap to the rear. This aligns the thrust surfaces of both halves of the bearing. 13. Retain the forward pressure on the crankshaft. Tighten the cap bolts to specifications. 15. Measure the crankshaft end-play as follows: a. Mount a dial gauge to the engine block and position the tip of the gauge to read from the crankshaft end. Carefullv the crankshaft toward the rear of the engine and hold it there while you the gauge. c. Carefully pry the crankshaft toward the front of the engine and read the gauge. d. Confirm that the reading is within specifications. not, install a new thrust bearing and repeat the procedure. If the reading is still out of specifications with a new bearing, have a machine shop inspect the thrust surfaces of the crankshaft, and if possible, repair it. 16. Rotate the crankshaft so as to position the first rod journal to the bottom of its stroke. Fig. 56 After the cap is removed again, use the scale supplied with the gauging material to check the clearance Fig. 57 A dial gauge may be used to check crankshaft end-play... ENGINE OVERHAUL 7-23 2. Unless new pistons are installed, be sure to install the pistons in the cylinders from which they were removed. The numbers on the connecting rod and bearing cap must be on the same side when installed in the cylinder bore. If a connecting rod is ever transposed from one engine or cylinder to another, new bearings should be fitted and the connecting rod should be numbered to correspond with the new cylinder number. The notch on the piston head goes toward the front of the engine. 3. Install all of the rod bearing inserts into the rods and caps. 4. lnstall the rings to the pistons. Install the oil control ring first, then the second compression-ring the top compression ring-Use a piston ring expander tool to aid in installation and to help reduce the chance of breakage. 5. Make sure the ring gaps are properly spaced around the circumference of the piston. Fit a piston ring compressor around the piston and slide the piston and connecting rod assembly down into the cylinder bore, pushing it in with the wooden hammer handle. Push the piston down until it is only slightly below the top of the cylinder bore. Guide the connecting rod onto the crankshaft bearing journal carefully, to avoid damaging the crankshaft. 6. Check the bearing clearance of all the rod bearings, fitting them to the crankshaft bearing journals. Follow the procedure in the crankshaft 1-Force crankshaft to forward position installation above. 7. After the bearings have been fitted, apply a light coating of assembly oil to the journals and bearings. 8. Turn the crankshaft until the appropriate bearing journal is at the bottom of its stroke. then the assemblv all the wav down until the connecting rod bearing seats on the crankshaft Be careful not to allow the bearing cap screws to strike the crankshaft bearing journals and damage them. 9. After the piston and connecting rod assemblies have been installed, check the connecting rod side clearance on each crankshaft journal. 10. Prime and install the oil pump and the oil pump intake tube. 11. Install the auxiliarylbalance shaftlassembly if equipped. I I Fig. 59 Carefully pry the crankshaft back and forth while reading the dial gauge for end-play Fig. 58 ...or you can use a feeler gauge Fig. 60 Checking the piston ring-to-ring groove side clearance using the ring and a feeler gauge Pistons and Connecting Rods See Figures and 67 1. Before installing the pistonlconnecting rod assembly, oil the pistons, piston rings and the cylinder walls with light engine oil. Install connecting rod bolt protectors or rubber hose onto the connecting rod Also perform the following: a. Select the proper ring set for the size cylinder bore. b. Position the ring in the bore in which it is going to be used. c. Push the ring down into the bore area where normal ring wear is not encountered. d. Use the head of the piston to position the ring in the bore so that the ring is square with the cylinder wall. Use caution to avoid damage to the ring or cylinder bore. e. Measure the gap between the ends of the ring with a feeler gauge. Ring gap in a worn cylinder is normally greater than specification. If the ring gap is greater than the specified limits, try an oversize ring set. f. Check the ring side clearance of the compression rings with a feeler gauge inserted between the ring and its lower land according to specification. The gauge should slide freely around the entire ring circumference without binding. Any wear that occurs will form a step at the inner portion of the lower land. If the lower lands have high steps, the piston should be replaced. Fig. 64 Piston ring arrangement 7-24 ENGINE OVERHAUL Fig. 61 The notch on the side of the bearing cap matches the tang on the bearing insert I Fig. 62 Most rings are marked to show which side of the ring should face up when installed to the piston GROOVED COMPRESSION OIL EXPANDER SPACER Fig. 63 Install the piston and rod assembly into the block using a ring compressor and the handle of a hammer RIGHT BANK LEFT BANK ARROW TOWARD NUMBERED OF ROD Flg. 65 Checking the connecting rod side clearance Fig. 67 Piston and rod positioning on a Ford V8, looking aft ENGINE OVERHAUL 7-25 Camshaft, Lifters And Timing Assembly 1. lnstall the camshaft. 2. Install the into their bores. 3. Install the timing gearsichain assembly. Cylinder 1. lnstall the cylinder using new gaskets. 2. Assemble the rest of the valve train (pushrods and rocker arms shafts). STARTING THE ENGINE Now that the engine is installed and every wire and hose is properly connected, go back and double check that all coolant and vacuum hoses are connected. Check that your oil drain plug is installed and properly tightened. If not already done, install a new oil filter onto the engine. Fill the crankcase with the proper amount and grade of engine oil. Fill the cooling system with a 50150 mixture of coolantiwater on models with a closed system. Connect the battery. 2. Start the engine. Keep your eye on your oil pressure indicator; if it does not indicate oil pressure within 10 seconds of starting, turn the engine off. Damage to the engine can result if it is allowed to run with no oil pressure. Check the engine oil level to make sure that it is full. Check for any leaks and if found, repair the leaks before continuing. If there is still no indication of oil pressure, you may need to prime the system. 3. Confirm that there are no fluid leaks (oil or other). 4. Allow the engine to reach normal operating temperature. 5. At this point you can perform any necessary checks or adjustments, such as checking the ignition timing. 6. lnstall any remaining components that were removed. BREAKING IT IN Make the first hours on the new engine, easy ones. Vary the speed but do not accelerate hard. Most importantly, do not lug the engine, and avoid sustained high speeds until at least 20 hours. Check the engine oil and coolant levels frequently. Expect the engine to use a little oil until the rings seat. Change the oil and filter at 20 hours and then follow the normal maintenance intervals from there out. KEEP IT MAINTAINED Now that you have just gone through all of that hard work, keep yourself from doing it all over again by thoroughly maintaining it. Not that you may not have maintained it before, heck you could have had a couple of thousand hours on it before doing this. However, you may have bought the vehicle used, and the previous owner did not keep up on maintenance. Which is why you just went through all of that hard work. See? 7-26 OIL RlNG SPACER COMPRESSION RlNG tCOMPRESSION RlNG Front Fig. 66 Piston ring spacing CARBURETED FUEL SYSTEM REMOVAL INSTALLATION DECELERATION VALVE ALL EXC . FORD ELECTRIC FUEL PUMP FORD V8 HOLLEY 2300 2 BBL FORD HOLLEY 41501416014175 4 BBL VACUUM TEST MECHANICAL FUEL PUMP OPERATION OPERATION ....................... BASIC FUNCTIONS ROCHESTER 2BBL CARBURETOR CIRCUITS ROCHESTER 4 BBL FUEL & AIR METERING SPECIFICATIONS ROCHESTER 2 BBL TROUBLESHOOTING ADJUSTMENT ..................... DIAGRAMS AUTOMATIC CHOKE DECELERATION VALVE CHOKE UNLOADER FUNCTION CHECK ELECTRIC CHOKE REMOVAL & INSTALLATION FLOAT DROP ELECTRIC FUEL PUMP FLOAT LEVEL COMPONENT REPLACEMENT IDLE SPEED MIXTURE CIRCUIT BREAKER INTERMEDIATE CHOKE ROD ....... RELAY & BRACKET PUMP ROD DESCRIPTION VACUUM BREAK FUEL SYSTEM CHECKS ASSEMBLY ....................... PRESSURE TEST CLEANING & INSPECTION REMOVAL INSTALLATION DISASSEMBLY ..................... FUEL AND COMBUSTION REMOVAL INSTALLATION .......... COMBUSTION ROCHESTER 4 BBL ................. FUEL ADJUSTMENT ..................... FUEL PUMP ACCELERATOR PUMP ROD ELECTRIC CHOKE ROD MECHANICAL FLOATLEVEL HOLLEY 2300 2 BBL IDLE SPEED & MIXTURE ASSEMBLY ....................... VACUUM BREAK CLEANING INSPECTION ........... ASSEMBLY DISASSEMBLY CLEANING & INSPECTION REMOVAL & INSTALLATION .......... DESCRIPTION ADJUSTMENT DISASSEMBLY ACCELERATOR PUMP CLEARANCE . . REMOVAL & INSTALLATION ACCELERATOR PUMP STROKE ..... CHOKE UNLOADER TORQUE CHOKE VACUUM CARBURETOR APPLICATIONS FLOATLEVEL 1986-90 HOLLEY 41501416014175 4 BBL ........ 1991-96 ADJUSTMENT ACCELERATOR PUMP CLEARANCE . . CARBURETOR 8-40 ACCELERATOR PUMP STROKE ..... HOLLEY BBL AUTOMATIC CHOKE HOLLEY 4 BBL CHOKE UNLOADER ROCHESTER 2BBL CHOKE VACUUM QUALIFICATION ... ROCHESTER 4BBL ............... FLOATLEVEL TROUBLESHOOTING SECONDARY THROTTLE COMBUSTION RELATED VALVEPLATE PISTON FAILURES ASSEMBLY COMMON PROBLEMS CLEANING INSPECTION WIRING DIAGRAMS DISASSEMBLY REMOVAL & INSTALLATION ............ MECHANICAL FUEL PUMP DESCRIPTION 1998 & V8 FUEL TEST V8 PRESSURE TEST 1997 8-2 FUEL SYSTEMS-CARBURETORS Fuel recommendations have become more complex as the chemistry of modern gasoline changes. The major driving force behind the changes in gasoline chemistry is the search for additives to replace lead as an octane booster and lubricant. These new additives are governed by the types of emissions they produce in the combustion process. Also, the replacement additives do not always provide the same level of combustion stability, making a fuel's octane rating less meaningful. In the 1960's and leaded fuel was common. The lead served two functions. First, it served as an octane booster (combustion stabilizer) and second, in engines, it served as a valve seat lubricant. For 2-stroke engines, the primary benefit of lead was to serve as a combustion stabilizer. Lead served very well for this purpose, even in high heat applications. Todav, all lead has been removed from the This means that thebenefit of lead as an octane booster has Several substitute octane boosters have been introduced in the of lead. While many are adequate in an engine, most do not perform as well as lead did, even though the octane rating of the fuel is the same. OCTANE RATING octane rating is a measurement of how stable the fuel is when heat is introduced. Octane rating is a major when deciding whether a fuel is suitable for a particular application. For example, in an engine, we want the fuel to ignite when the spark plug fires and not before, even under high pressure and temperatures. Once the fuel is ignited, it must burn slowly and smoothly, even though heat and pressure are building up while the burn occurs. The unburned fuel should be ignited by the traveling flame front, not by some other source of ignition, such as carbon deposits or the heat from the expanding gasses. A fuel's octane rating is known as a measurement of the fuel's anti-knock properties (ability to burn without exploding). Usually a fuel with a higher octane ratinq can be to a more severe combustion environment before or-abnormal combustion occurs. To understand how two aasoline can be different, even though they have the same rating, we need to know how octane rating is determined. The American Society of Testing and Materials (ASTM) has developed a universal method of determining the octane rating of a fuel sample. The octane rating you see on the pump at a fuel dock is known as the pump octane number. Look at the small print on the pump. The rating has a formula. The rating is determined by the method. This number is the average of the research octane reading and the motor octane rating. The Research Octane Rating is a measure of a fuel's anti-knock properties under a light load or part throttle conditions. During this test, combustion heat is easily dissipated. The Motor Octane Rating is a measure of a fuel's anti-knock properties under a heavy load or full throttle conditions, when heat buildup is at maximum. VAPOR PRESSURE Fuel vapor pressure is a measure of how easily a fuel sample evaporates. Many additives used in gasoline contain aromatics. Aromatics are light hydrocarbons distilled off the top of a crude oil sample. They are effective at increasing the research octane of a fuel sample but can cause vapor lock (bubbles in the fuel line) on a very hot day. If you have an inconsistent running engine and you suspect vapor lock, use a piece of clear fuel line to look for bubbles, indicating that the fuel is vaporizing. One negative side effect of aromatics is that they create additional combustion products such as carbon and varnish. If your engine requires high octane fuel to prevent detonation, de-carbon the engine more frequently with an internal engine cleaner to prevent ring sticking due to excessive varnish buildup. ALCOHOL-BLENDED FUELS When the Environmental Protection Agency mandated a phase-out of the leaded fuels in January of 1986, fuel suppliers needed an additive to improve the octane rating of their fuels. Although there are multiple methods currently employed, the addition of alcohol to gasoline seems to be favored because of its favorable results and low cost. Two types of alcohol are used in fuel today as octane boosters, methanol (wood alcohol) or ethanol (grain alcohol). When used as a fuel additive, alcohol tends to raise the research octane of the fuel. There are, however, some special considerations due to the effects of alcohol in fuel. Since alcohol contains oxygen, it replaces gasoline without oxygen content and tends to cause the mixture to become leaner. On older engines, the leaching affect of alcohol may, in time, cause fuel lines and plastic components to become brittle to the point of cracking. Unless replaced, these cracked lines could leak fuel, increasing the potential for hazardous situations. When alcohol blended fuels become contaminated with water, the water combines with the alcohol then settles to the bottom of the tank. This leaves the gasoline on a top layer. Modern fuel lines and plastic fuel system components have been specially formulated to resist alcohol leaching effects. ALTITUDE OPERATION At elevated altitudes there is less oxygen in the atmosphere than at sea level. Less oxygen means lower combustion efficiency and less power output. As a general rule, power output is reduced three percent for every thousand feet above sea level. On carbureted engines, re-jetting for high altitude does not restore lost power, it simply corrects the air-fuel ratio for the reduced air density and makes the most of the remaining available power. The most important thing to remember when re-jetting for high altitude is to reverse the jetting when returning to sea level. If the jetting is left lean when you return to sea level conditions, the correct ratio will not be achieved and possible engine damage may occur. RECOMMENDATIONS All engine covered here are designed to run on unleaded fuel. Never use leaded fuel in your boat's engine. The minimum octane rating of fuel being used for your engine must be at least 87 AKI (outside the US: 90 RON), which means regular unleaded, but some engines may require higher octane ratings. OMC actually recommends the use of 89 AKI (93 RON) fuel as the ideal-in fact, anything less than this on many engines will require a change to the ignition timing. Fuel should be selected for the brand and octane that performs best with your engine. Check your owner's manual if in doubt. Premium unleaded is more stable under severe conditions but also produces more combustion products. Therefore, when using premium unleaded, more frequent de-carboning is necessary. The use of a fuel too low in octane (a measure of anti-knock quality) will result in spark knock. Newer systems have the capability to adjust the engine's ignition timing to compensate to some extent, but if persistent knocking occurs, it may be necessary to switch to a higher grade of fuel. Continuous or heavy knocking may result in engine damage. In a high heat environment like an modern engine, the fuel must be very stable to avoid detonation. If any parameters affecting combustion change suddenly (the engine runs lean for example), uncontrolled heat buildup will occurs very rapidly. The combustion process is affected by several interrelated factors. This means that when one factor is changed, the other factors also must be changed to maintain the same controlled burn and level of combustion stability. Compression-determines the level of heat buildup in the cylinder when the air-fuel mixture is compressed. As compression increases, so does the potential for heat buildup Ignition Timing--determines when the gasses will start to expand in relation to the motion of the piston. If the ignition timing is too advanced, gasses will be ignited and begin to expand too soon, such as they would during pre-ignition. The motion of the piston opposes the expansion of the gasses, resulting in extremely high combustion chamber pressures and heat. If the ignition timing is retarded, the gases are ignited later in relation to piston position. This means that the piston has already traveled back down the bore toward the bottom of the cylinder, resulting in less usable power. FUEL SYSTEMS-CARBURETORS 8-3 Fuel Mixture-determines how efficient the burn will be. A rich mixture burns slower than a lean one. If the mixture is too lean, it can't become explosive. The slower the burn, the cooler the combustion chamber, because pressure buildup is gradual. Fuel Quality (Octane Rating)-determines how much heat is necessary to ignite the mixture. Once the burn is in progress, heat is on the rise. The unburned poor quality fuel is ignited all at once by the rising heat instead of burning gradually as a flame front of the burn passing by. This action results in detonation (pinging). There are two types of abnormal combustion-pre-ignition and detonation. Pre-ignition-occurswhen the air-fuel mixture is ignited by some incandescent source other than the correctly timed spark from the spark Detonation-occurs when excessive heat and or pressure ignites the mixture rather than the spark plug. The burn becomes explosive. In general, anything that can cause abnormal heat buildup can be enough to push an engine over the edge to abnormal combustion, if any of the four basic factors previously discussed are already near the danger point, for example, excessive carbon buildup raises the compression and retains heat as glowing embers. Troubleshooting fuel systems requires the same techniques used in other areas. A thorough, systematic approach to troubleshooting will pay big rewards. Build your troubleshooting checklist, with the most likely offenders at the top. Use your experience to adjust your list for local conditions. Everyone has been tempted to jump into the carburetor on a vague hunch. Pause a moment and review the facts when this urge occurs. In order to accurately troubleshoot a carburetor or fuel system problem, you must first verify that the problem is fuel related. Many symptoms can have several different possible causes. Be sure to eliminate mechanical and electrical systems as the potential fault. Carburetion is the number one cause of most engine problems but there are other possibilities. One of the toughest tasks with a fuel system is the actual troubleshooting. Several tools are at your disposal for making this process very simple. A timing light works well for observing carburetor spray patterns. Look for the proper amount of fuel and for proper atomization in the two fuel outlet areas (main nozzle and bypass holes). The strobe effect of the lights helps you see in detail the fuel being drawn through the throat of the carburetor. On multiple carburetor engines, always attach the timing light to the cylinder you are observing so the strobe doesn't change the appearance of the patterns. If you need to compare two cylinders, change the timing light hookup each time you observe a different cylinder. Pressure testing fuel pump output can determine whether the fuel spray is adequate and if the fuel pump diaphragms are functioning correctly. A pressure gauge placed between the fuel and the will test the entire fuel delivery system. Normally a fuel system problem will show up at high speed where the fuel demand is the greatest. A common symptom of a fuel pump output problem surging at wide open throttle but normal operation at slower speeds. To check the fuel pump output, install the pressure gauge and accelerate the engine to wide-open throttle. Observe the pressure gauge needle. It should always swing up the value indicated in the specification charts and remain steady. This reading would indicate a system that is functioning properly. If the needle gradually swings down toward zero, fuel demand is greater than the fuel system can supply. This reading isolates the problem to the fuel delivery system (fuel tank or line). To confirm this, an auxiliary tank should be installed and the engine re-tested. Be aware that a bad anti-siphon valve on a built-in tank can create enough restriction to cause a lean condition and serious engine damage. If the needle movement becomes erratic, suspect a ruptured diaphragm in the fuel pump. To check for air entering the fuel system, install a clear fuel hose between the fuel screen and fuel pump. If air is in the line, check all fittings back to the boat's fuel tank. Spark plug tip appearance is a good indication of combustion efficiency. The tip should be a light tan. A White insulator or small beads on the insulator indicate too much heat. A dark or oil fouled insulator indicates incomplete combustion. To properly read spark plug tip appearance, run the engine at the RPM you are testing for about 15 seconds and then immediately turn the engine OFF without changing the throttle position. Reading spark plug tip appearance is also the proper way to test jet verifications in high altitude. COMMON PROBLEMS Fuel Delivery Many times fuel system troubles are caused by a plugged fuel filter, a defective fuel pump or by a leak in the line from the fuel tank to the fuel pump. A defective choke may also cause problems. Would you believe, a majority of starting troubles which are traced to the fuel system are the result of an empty fuel tank or aged sour fuel. Sour Fuel Under average conditions (temperate climates), fuel will begin to break down in about four months. A gummy substance forms in the bottom of the fuel tank and in other areas. The filter screen between the tank and the carburetor and small passages in the carburetor will become clogged. The gasoline will begin to give off an odor similar to rotten eggs. Such a condition can cause the owner much frustration, time in cleaning components and the expense of replacement or overhaul parts for the carburetor. Even with the high price of fuel, removing gasoline that has been standing unused over a long period of time is still the easiest and least expensive preventative maintenance possible. In most cases, this old gas can be used without harmful effects in an automobile using regular gasoline. A gasoline presentative will keep the fuel fresh for up to twelve months. These products are available in most areas under various trade names. Choke Problems When the engine is hot, the fuel system can cause starting problems. After a hot engine is shut down, the temperature inside the fuel bowl may rise to 200F and cause the fuel to actually boil. All carburetors are vented to allow this pressure to escape to the atmosphere. However, some of the fuel may percolate over the high-speed nozzle. If the choke should stick in the open position, the engine will be hard to start. If the choke should stick in the closed position, the engine will flood, making it very difficult to start. In order for this raw fuel to vaporize enough to burn, considerable air must be added to lean out the mixture. Therefore, the only remedy is to remove the spark plugs, ground the leads, crank the engine through about ten revolutions, clean the plugs, reinstall the plugs and start the engine. If the needle valve and seat assembly is leaking, an excessive amount of fuel may enter the reed housing in the following manner. After the engine is shut down, the pressure left in the fuel line will force fuel past the leaking needle valve. This extra fuel will raise the level in the fuel bowl and cause fuel to overflow into the reed housing. A continuous overflow of fuel into the reed housing may be due to a sticking inlet needle or to a defective float, which would cause an extra high level of fuel in the bowl and overflow into the reed housing. Rough Engine If an engine does not idle smoothly, the most reasonable approach to the problem is to perform a tune-up to eliminate such areas as: Defective points Faulty spark plugs Timing out of adjustment Other problems that can prevent an engine from running smoothly include: An air leak in the intake manifold Uneven compression between the cylinders Of course any problem in the carburetor affecting the mixture will also prevent the engine from operating smoothly at idle speed. These problems usually include: Too high a fuel level in the bowl A heavy float Leaking needle valve and seat Defective automatic choke Improper adjustments for idle mixture or idle speed Excessive Fuel Consumption Excessive fuel consumption can be the result of any one of four conditions or a combination of all. Inefficient engine operation. 8-4 FUEL SYSTEMS -CARBURETORS Faulty condition of the hull, including excessive marine growth. Poor boating habits of the operator. Leaking or out-of-tune carburetor. If the fuel consumption suddenly increases over what could be considered normal, then the cause can probably be attributed to the engine or boat and not the operator. Marine growth on the hull can have a very marked effect on boat performance. This is why sailboats always try to have a haul-out as close to race time as possible. While you are checking the bottom, take note of the propeller condition. A bent blade or other damage will definitely cause poor boat performance. If the hull and propeller are in good shape, then check the fuel system for possible leaks. Check the line between the fuel pump and the carburetor while the engine is running and the line between the fuel tank and the pump when the engine is not running. A leak between the tank and the pump many times will not appear when the engine is operating, because the suction created by the pump drawing fuel will not allow the fuel to leak. Once the engine is turned off and the suction no longer exists, fuel may begin to leak. If a minor tune-up has been performed and the spark plugs, points (if equipped) and timing are properly adjusted, then the problem most likely is in the carburetor and an overhaul is in order. Check the needle valve and seat for leaking. Use extra care when making any adjustments affecting the fuel consumption, such as the float level or automatic choke. Engine Surge If the engine operates as if the load on the boat is being constantly increased and decreased, even though an attempt is being made to hold a constant engine speed, the problem can most likely be attributed to the fuel pump or a restriction in the fuel line between the tank and the carburetor. COMBUSTION RELATED PISTON FAILURES When an engine has a piston failure due to abnormal combustion, fixing the mechanical portion of the engine is the easiest part of the equation. The hard part is determining what caused the problem in order to prevent a repeat failure. Think back to the four basic areas that affect combustion to find the cause of the failure. Since you probably removed the cylinder head, inspect the failed piston and look for excessive deposit buildup that could raise compression or retain heat in the combustion chamber. Statically check the wide open throttle timing. Be sure that the timing is not over advanced. It is a good idea to seal these adjustments with paint to detect tampering. Look for a fuel restriction that could cause the engine to run lean. Don't forget to check the fuel pump, fuel tank and lines, especially if a built in tank is used. Be sure to check the anti-siphon valve on built in tanks. If everything else looks good, the final possibility is poor quality fuel. Traditional carburetor theory often involves a number of laws and principles. The diagram illustrates several carburetor basics. If you blow air across a straw inserted into a container of liquid, a pressure drop is created in the straw column. As the liquid in the column is expelled, an atomized mixture (air and fuel droplets) is created. In a carburetor this is mostly air and a little fuel. The actual ratio of air to fuel differs with engine conditions but is usually from parts air to one part fuel at optimum cruise to as little as 7 parts air to one part fuel at full choke. Using our example, what if the top of the container is covered and sealed around the straw, what will happen? No flow. This is typical of a clogged carburetor bowl vent. If the base of the straw is clogged or restricted what will happen? No flow or low flow. This represents a clogged main jet. If the liquid in the glass is lowered and you blow through the straw with the same force what will happen? Not as much fuel will flow. A lean condition occurs. If the fuel level is raised and you blow again at the same velocity what happens? The result is a richer mixture. Atomized fuel Air Carburetor operating principles Fig. 1 If you blow air across a straw inserted into a container of liquid, a pressure drop is created in the straw column. As the liquid in the column is expelled, an atomized mixture (air and fuel is created FUEL AIR METERING The carburetor is merely a metering device for mixing fuel and air in the proper proportions for efficient engine operation. Float Systems See Figure 2 A small chamber in the carburetor serves as a fuel reservoir. A float valve admits fuel into the reservoir to replace the fuel consumed by the engine. If the carburetor has more than one reservoir, the fuel level in each reservoir (chamber) is controlled by identical float systems. Fuel level in each chamber is extremely critical and must be maintained accurately. Accuracy is obtained through proper adjustment of the floats. This adjustment will provide a balanced metering of fuel to each cylinder at all speeds. Following the fuel through its course, from the fuel tank to the combustion chamber of the cylinder, will provide an appreciation of exactly what is taking place. In order to start the engine, the fuel must be moved from the tank to the carburetor by a fuel pump installed in the fuel line. After the engine starts, the fuel passes through the pump to the carburetor. All systems have some type of filter installed somewhere in the line between the tank and the carburetor. Most engines also have a filter as valve Air intake Venturi High speed needle \ High speed orifice Fig. 2 Fuel flow through a venturi, showing principal and related parts controlling intake and outflow BASIC FUNCTIONS See Figure 1 an integral part of the carburetor. and Throttle slow speed FUEL SYSTEMS -CARBURETORS 8-5 At the carburetor, the fuel passes through the inlet passage to the needle and seat and then into the float chamber (reservoir). A float in the chamber rides up and down on the surface of the fuel. After fuel enters the chamber and the level rises to a predetermined point, a tang on the float closes the inlet needle and the flow entering the chamber is cut off. When fuel leaves the chamber as the engine operates, the fuel level drops and the float tang allows the inlet needle to move off its seat and fuel once again enters the chamber. In this manner, a constant reservoir of fuel is maintained in the chamber to satisfy the demands of the engine at all speeds. A fuel chamber vent hole is located near the top of the carburetor body to permit atmospheric pressure to act against the fuel in each chamber. This pressure assures an adequate fuel supply to the various operating systems. Mixture See Figure 3 A suction effect is created each time the piston moves upward in the cylinder. This suction draws air through the throat of the carburetor. A restriction in the throat, called a venturi, controls air velocity and has the effect of reducing air pressure at this point. The difference in air pressures at the throat and in the fuel chamber causes the fuel to be pushed out of metering jets extending down into the fuel chamber. When the fuel leaves the jets, it mixes with the air passing through the venturi. This mixture should then be in the proper proportion for burning in the cylinders for maximum engine performance. In order to obtain the proper mixture for all engine speeds, some models have high and low speed jets. These jets have adjustable needle valves that are used to compensate for changing atmospheric conditions. In almost all cases, the high-speed circuit has fixed high-speed jets and is not adjustable. A throttle valve controls the flow of airlfuel mixture drawn into the combustion chambers. A cold engine requires a richer fuel mixture to start and during the brief period it is warming to normal operating temperature. A choke valve is placed ahead of the metering jets and venturi. As this valve begins to close, the volume of air intake is reduced, thus enriching the mixture entering the cylinders. When this choke valve is fully closed, a very fuel mixture is drawn into the cylinders. The throat of the carburetor is usually referred to as the barrel. Carburetors with single, double or four barrels have individual metering jets, needle valves, throttle and choke plates for each barrel. Single and two barrel carburetors are fed by a single float and chamber. Induced low air Venturi Atmospheric air pressure Fig. 3 Air flow principle of a modern carburetor CARBURETOR CIRCUITS The following section illustrates the circuit functions and locations of a typical marine carburetor. Starting Circuit + See Figure 4 The choke plate is closed, creating a partial vacuum in the venturi. As the piston rises, negative pressure in the crankcase draws the rich air-fuel mixture from the float bowl into the venturi and then on into the engine. Fig. 4 Carburetor starting circuit Low Speed Circuit See Figure 5 Zero-one-eighth throttle, when the pressure in the crankcase is lowered, the air-fuel mixture is discharged into the venturi through the pilot outlet because the throttle plate is closed. No other outlets are exposed to low venturi pressure. The fuel is metered by the pilot jet. The air is metered by the pilot air jet. The combined air-fuel mixture is regulated by the pilot air screw. Mid-Range Circuit See Figure 6 One-eighth-three-eighths throttle, as the throttle plate continues to open, the air-fuel mixture is discharged into the venturi through the bypass holes. As the throttle plate uncovers more bypass holes, increased fuel flow results because of the low pressure in the venturi. on the model, there could be two, three or four bypass holes. Air Fuel Fig. 5 Carburetor lowspeed circuit FUEL SYSTEMS -CARBURETORS Air Fuel Good Unsuitable Fig. 6 Carburetor mid-range circuit High Speed Circuit See Figure 7 Three-eighths-wide-open throttle, as the throttle plate moves toward wide open, we have maximum air flow and very low pressure. The fuel is metered through the main jet and is drawn into the main discharge nozzle. Air is metered by the main air jet and enters the discharge nozzle, where it combines with fuel. The mixture atomizes, enters the venturi and is drawn into the engine. Fuel Fig. 7 Carburetor high speed circuit REMOVAL INSTALLATION Always disconnect the battery cables before attempting to work on the fuel system. Never smoke or allow open flame near the engine--this sounds like an obvious precaution, but you'd be surprised at how many people forget! No matter how much they look alike, marine carburetors are completely different from automotive carburetors. Never substitute an automotive carburetor for the one on your engine! Venting procedures are not the same and an automotive carburetor could allow dangerous vapors to escape into the bilge. Don't even think about it. Open the engine hatch or remove the covers and then disconnect the battery cables. Turn the fuel OFF shut down the fuel supply at the tank. 2. Remove the flame arrestor after disconnecting the vent hose. It's always a good idea to plug the throttle bores with a clean, lint-free cloth. 3. Disconnect the throttle cable at the carburetor and carefully move it out of the way. 4. Using two open-end wrenches, hold the fuel inlet nut at the carburetor securely and loosen the fuel line nut. Disconnect the two and carefully move the line out of the way. Plug both the inlet and line open ends to prevent fuel seepage. 5. Tag and disconnect the electric choke lead only). 6. Tag and disconnect any other lines, leads or hoses that may be in the way of removal. 7. Loosen and remove the carburetor mounting nuts (early models) or bolts and washers and lift the unit off the manifold. Plug the opening with a clean lint-free cloth. To Install: 8. Clean the mating surfaces thoroughly of all residual gasket material. 9. Position a new gasket and then install the carburetor. On early models, tighten the nuts to 10-14 ft. Ibs. (13-19 Nm). On all others, tighten the bolts to 12-15 ft. Ibs. (16-20 Nm). Hopefully you remembered to remove the rag! 10. Reconnect the fuel line to the inlet line after removing the plugs and tighten it to 18 ft. Ibs. (24 Nm). Don't forget to use two wrenches. 11. Connect the choke lead on the engine. 12. Install and adjust the throttle cable as detailed in the Maintenance section. On the and engines, make sure that the distance between the centers of the two ball studs is 2 in. on the engines, the distance should be 2 3/32 in. 13. Install the flame arrestor and reconnect the vent line. 14. Connect the battery cables. Start the engine and ensure there are no fuel leaks; shut down the engine immediately if there are. Check and adjust the idle speed and mixture. DISASSEMBLY See Figures 8 thru 13 Always be certain that your carburetor rebuild kit is for marine applications. 1. Remove the carburetor. 2. Remove the idle vent valve and the pump link. 3. Remove the small screw at the end of the choke shaft. Remove the fast idle cam screw and then lift off the fast idle linkage as an assembly. 4. Remove the air horn attaching screws and lift the horn straight up and off the carburetor body. 5. Remove the two choke valve retaining screws-the ends of the screws are staked, so you may have to file the ends first. Lift out the valve. 6. Remove the choke cover with the coil attached. Pull up the gasket and lift out the baffle plate. Carefully (and slowly) rotate the choke shaft counterclockwise until the piston comes out of its bore and then lift out the entire assembly. 7. Turn the air horn upside down and pull out the float's hinge pin. Lift out the float and remove the needle. 8. Press down on the power piston shaft until the spring snaps, forcing the piston out of the casting. Remove the piston. 9. Remove the accelerator pump plunger and the pump leverlshaft assembly. 10. Remove the 2 choke housing screws and separate it from the horn. Discard the gasket. 11. Remove the pump plunger, return spring and main metering jets. 12. Remove the power valve from the body. Certain models will have an aluminum inlet ball in the bottom of the well-it will fall out when you turn the carb over, so don't lose it. 13. Loosen the mounting screws and pull out the venture cluster. 14. The discharge ball spring is held in place by a retainer; pull it out with needle-nose pliers and remove the spring and ball. 15. Turn the carburetor back over an remove the 3 throttle body screws. Separate the throttle body from the bowl. FUEL SYSTEMS -CARBURETORS 8-7 THERMOSTAT HINGE CLUSTER GASKET POWER VALVE GASKET BODY SPRING ig. 8 Exploded view of a typical Rochester carburetor G A S K E T I I I PUMP SPRING GUIDE UMP DISCHARGE LEVER BODY FUEL SYSTEMS -CARBURETORS ASSEMBLY Do not disassemble the throttle body-replacement parts are NOT available. CLEANING INSPECTION Never use a wire brush or drill to clean jet passages or in the carburetor. Never allow the carburetor to soak in a cleaner bath for more than two hours. In fact, we recommend using spray cleaner. Never immerse the float assembly, needle, accelerator pump plunger or fuel filter in cleaner. Wipe them carefully with a clean cloth. Otherwise clean all allowable parts with carb cleaner and then dry with compressed air if at all possible. Blow out and through all passages to ensure there is no foreign material clogging them. Check the float needle and seat, if either is worn or damaged, replace them as a matched set. Check the float assembly and hinge pin for wear or damage, replace as necessary. Check the pump plunger, return spring, piston spring, idle mixture needle and all levers and linkages for wear or damage. Replace as necessary. Check the throttle valve shaft for excessive looseness in the throttle body. Check that the valve and shaft do not bind through their range of operation and that the valve opens and closes fully. Replace the assembly if it fails any of these tests. Check the choke valve lever and shaft for excessive looseness in the air horn, Check that the valve, lever and shaft do not bind through their range of operation and that the valve opens and closes fully. Replace the air horn assembly if it fails any of these tests. See Figures 8 and 14 1. lnstall the idle mixture adjusting needle into the throttle body and screw it down until it contacts the seat. Now back it out 1 112 turns. Position a new gasket and install the throttle body. Tighten the screws to 50 inch Ibs. (5.6 Nm). Always use a non-vent gasket. Never use a vented automotive gasket. 3. the steel discharge check ball and spring into the body and then insert the retainer. 4. lnstall the venture cluster with a new gasket. Make sure that the undercut screw is installed in the center hole with a new gasket. 5. lnstall the main metering and the power valve using new gaskets. 6. Slide the pump return spring into the pump and then install the inlet screen on the bottom of the bowl. 7. lnstall the choke housing with a new gasket. Attach the choke piston to the piston pin and the flat section on the side of the choke piston must face out toward the air horn. Push the shaft into the air horn and rotate it until the piston enters the bore. 8. Position the choke valve onto the shaft so the letters are facing up and screw in the retaining screws finger-tight, lnstall the choke rod lever and the trip lever to the end of the shaft. Center the valve so that the clearance between the lever and the air horn is 0.020 in. (0.51 mm), tighten the screws securely and then rouqh up their ends to prevent them from out. 9. lnstall the baffle aasket and thermostatic cover. Rotate the cover until the then tighten the retainers and screws securely. 10. lnstall the outer pump lever into the air horn and then install the inner arm; tighten the screw securely. 11. lnstall the pump plunger to the inner arm so that the shaft is pointing inward. lnstall the retainer. Vent .. ,. , Fig. 12 Now you can remove the metering Fig. 13 You'll need pliers to remove the rods and the venture cluster Fig. 14 Installing the venturi discharge ball retainer Fig. 9 Disconnect the pump link and the choke shaft Fig. Take apart the choke housing Fig. 11 After inverting the air horn, remove the float and power piston FUEL SYSTEMS -CARBURETORS 8-9 Position the screen on the float needle seat and then install the assembly onto the air horn. 13. lnstall the power piston into the vacuum cavity making sure that it can move without obstruction. Carefully stake the retainer to hold it in place. 14. lnstall a new air horn gasket and then attach the needle to the float. Carefully insert the needle into the float seat while, at the same time, guiding the float between the bosses. the hinge pin and check the float level and drop. 15. lnstall the horn to the float bowl. 16. lnstall the carburetor. ADJUSTMENT Float Level Floats With Vertical Seam See Figure 15 Following the disassembly procedure detailed previously, remove the bowl horn from the carburetor. 2. Turn the assembly upside down and check that the float pivots freely on the pin. Raise the float and let it fall--do not force it! Using a standard carburetor gauge, measure the distance between the bottom of the air horn gasket (remember it's upside down, so this will be the top) and the top of the float; it should be within the specifications given in your rebuild kit. Carefully bend the float arm (at the rear of the float) with needle nose pliers to achieve the correct measurement. Make sure the float stays in alignment. 4. Its usually a good idea to check the float drop now. 5. Recheck your measurements one more time. 6. Reinstall the air horn and carburetor. Floats With Horizontal Seam See Figure 16 Following the disassembly procedure detailed previously, remove the bowl horn from the carburetor. 2. Turn the assembly upside down and check that the float pivots freely on the pin. Raise the float and let it fall--do not force 3. Using a standard carburetor gauge, measure the distance between the bottom of the air horn gasket (remember it's upside down, so this will be the top) and the lower edge of the seam on the float; it should be within the specifications given in your rebuild kit. Carefully bend the float arm (at the rear of the float) with needle nose pliers to achieve the correct measurement. Make sure the float stays in alignment. 4. Its usually a good idea to check the float drop now. 5. Recheck your measurements one more time. 6. Reinstall the air horn while guiding the accelerator pump plunger the well. 7. Slide the idle speed needle spring over the needle and screw it back into the throttle body. lnstall the pump rod, choke rod and idle stop screw. 9. lnstall the carburetor. Hollow Floats See Figure 17 Following the disassembly procedure detailed previously, remove the bowl horn from the carburetor. 2. Turn the assembly upside down and check that the float pivots freely on the pin. Raise the float and let it fall--do not force it! 3. Using a standard carburetor gauge, measure the distance between the bottom of the air horn gasket (remember it's upside down, so this will be the top) and the lip at the toe of the float; it should be within the specifications given in your rebuild kit. Carefully bend the float arm (at the rear of the float) with needle nose pliers to achieve the correct measurement. Make sure the float stays in alignment. 4. Its usually a good idea to check the float drop now. 5. Recheck your measurements one more time. 6. Reinstall the air horn and carburetor. Float Drop See Figure 18 1. After checking the float level adjustment, turn the air over so it is right-side-up. 2. Allow the float to hang down freely and measure the distance between the bottom of the gasket and the lowest edge on the bottom of the float. On the and carburetor and later carbs, measure to the gasket seam at the toe of the float. 3. If your measurement is not within the specification given in the kit, carefully bend the float tang with needle-nose pliers until it comes within spec. 4. Recheck your measurements one more time. 5. Reinstall the air horn and carburetor. Speed Mixture Please refer to the Maintenance section for adjustment procedures. Pump Rod See Figure 19 Back out the idle stop screw and then close the throttle valves completely in their bores. 2. Position a pump gauge across the top of the air horn so that the leg is pointing down toward the top of the pump rod to the measurement listed in the Specifications chart. 3. If the lower edge of the gauge does not come in contact with the top of the rod, carefully bend the rod with needle-nose pliers until it does. Choke Unloader See Figure 20 Remove the flame arrestor. 2. Move the linkage to position the throttle valves in the fully open position. 3. Insert the proper gauge (or drill bit) between upper edge of the plate and the inner side of the air horn wall. The gauge should just slide if not, bend the tang on the throttle lever until the measurement is correct. INVERT AIR HORN WITH GASKET IN PLACE HORN GASKET TO ADJUST FLOAT LEVEL GAUGE SHOULD JUST TOUCH FLOATSEAM LEVE BEND HERE TO ADJUST CHECK FLOAT ALIGNMENT GAUGE FROM TOP OF FLOAT AIR HORN GASKET CHECK FLOAT ALIGNMENT MEASURE FROM LIP AT TOE OF FLOAT TO AIR HORN GASKET Fig. Float level adjustment-vertical seam Fig. 16 Float level adjustment-horizontal seam Fig. 17 Float level adjustment-hollow floats 8-10 FUEL SYSTEMS -CARBURETORS MEASURE SPECIFIED DISTANCE FROM CASKET SURFACE TO BOTTOM OF FLOAT Fig. 18 Float drop and early engines PLACE GAUGE ACROSS TOP OF AIR HORN TOUCH THROTTLEVALVES FULLY CLOSED Fig. 19 Pump rod adjustment I GAUGE BETWEEN UPPER EDGEOFCHOKE VALVE AND AIR HORN Fig. 20 Choke unloader adjustment Intermediate Choke and Engines DERATE 1. Remove the flame arrestor. 2. Remove the 3 mountina screws and lift off the thermostat cover, gasket and baffle. 3. Hold the choke valve closed and check that the edge of the actuator lever in the housing is lined up with the edge of the casting. If not, bend the choke rod with needle nose pliers at the bend just below the lever. Vacuum and Engines DERATE 1. Remove the flame arrestor. 2. Stretch a small rubber band over the vacuum break diaphragm plunger so that the diaphragm is fully seated. Make sure that the rubber band is not interfering with the vacuum break link's movement. 3. Pull up on the intermediate choke lever until the choke valve is fully closed and then insert the proper sized between the inner wall of the air horn and the upper edge of the valve. 4. Bend the vacuum break link at the 90" bend below the unit. Automatic and Engines See Figure 21 Remove the flame arrestor. . -- 2. Loosen the 3 choke cover mounting screws and then rotate the cover until the mark on the cover is in alignment with the index line on the housing. 3. Tighten the screws. Electric Engines Remove the flame arrestor. 2. Loosen the choke cover mounting screws and then rotate until the mark on the cover is in alignment with the index line on the housing. 3. If adjustment is necessary, move the cover one mark at a time, but never more than 2 marks in total from the index mark. 4. Tighten the screws. Fig. 21 Automatic choke adjustment DESCRIPTION The Rochester Quadrajet carburetor has two stages. The primary (fuel inlet) side has small 318 in, bores with a triple venturi setup equipped with plain-tube nozzles. The carburetor operates much the same as other carburetors using the venturi principle. The triple venturi, plus the small primary bores, makes for a more stable and finer fuel control during idle and partial throttle operation. When the throttle is partially open, the fuel metering is accomplished with tapered metering rods, positioned by a responsive piston and operating in specially designed jets. The secondary side has two large, 2 114 in., bores. These large bores, when added to the primary side bores, provide enough air capacity to meet most engine requirements. The air valve is used in the secondary side for metering control and backs-up the primary bores to meet air and fuel demands of the engine. The secondary air valve operates the tapered metering rods. These rods move in orifice plates and thus control fuel flow from the secondary nozzles in direct relation to the air flowing through the secondary bores. The float bowl is designed to avoid problems of fuel spillage during sharp turns of the boat which could result in engine cutout and delayed fuel flow. The bowl reservoir is smaller than most four-barrel carburetors to reduce fuel evaporation during hot engine shut down. The float system has one pontoon float and fuel valve which makes servicing much easier than on some other model carburetors. A fuel filter is located in the float bowl ahead of the float needle valve. This filter is easily removed for cleaning or replacement. The throttle body is made of aluminum as part of a weight-reduction program and also to improve heat transfer away from the fuel bowl and prevent the fuel from "percolating"during hot engine shut down. A heat insulator gasket is used between the throttle body and bowl to help prevent Always disconnect the battery cables before attempting to work on the fuel system. Never smoke or allow open flame near the engine-this sounds like an obvious precaution, but you'd be surprised at how many people forget! FUEL SYSTEMS -CARBURETORS 8-11 REMOVAL INSTALLATION ERATE No matter how much they look alike, marine are completely different from automotive carburetors. Never substitute an automotive carburetor for the one on your engine! Venting procedures are not the same and an automotive carburetor could dangerous vapors to escape into the bilge. Don't even think about it. Open the engine hatch or remove the covers and then disconnect the battery cables. Turn the fuel OFF shut down the fuel supply at the tank. 2. Remove the flame arrestor after disconnecting the vent hose. It's always a good idea to plug the throttle bores with a clean, lint-free cloth. 3. Disconnect the throttle cable hardware from the throttle bracket and lever anchor studs. Remove the cable and carefully move it out of the way. 4. Remove the retaining clip and disconnect the choke spring rod. 5. Using two open end line nut wrenches, hold the fuel inlet nut at the carburetor securely and loosen the fuel line nut. Disconnect the two and carefully move the line out of the way. Plug both the inlet and line open ends to prevent fuel seepage. 6. Loosen and remove the carburetor mounting (2 each) and washers, and lift the unit off the manifold. Plug the opening with a clean lint- free cloth. Remove the cable bracket. To Install: 7. Clean the mating surfaces thoroughly of all residual gasket material, position a new gasket and then install the carburetor. Certain models may use an adaptor or wedge plate, install this first. Tighten the nuts to 10-14 ft. Ibs. (13-19 Nm) and the bolts to 6-8 ft. Ibs. (8-11 Nm). Hopefully you remembered to remove the rag! 8. Reconnect the fuel line to the inlet line after removing the plugs and tighten it to 18 ft. Ibs. (24 Nm). Don't forget to use two wrenches. 9. Connect the choke spring rod and slide in the retaining clip. lnstall and adjust the throttle cable as detailed later in this section. 11. Install the flame arrestor and reconnect the vent line. 12. Connect the battery cables. Start the engine and ensure there are no fuel leaks; shut down the engine immediately if there are. Check and adjust the idle speed and mixture. DISASSEMBLY TE I) See Figures 22 thru 30 Always be certain that your carburetor rebuild kit is for marine applications. Remove the carburetor. 2. Place the carburetor on the workbench in the upright position. If servicing an older carburetor, remove the idle vent valve attaching screw, and then remove the idle vent valve assembly. Remove the clip from the upper end of the choke intermediate rod, disconnect the choke rod from the upper choke shaft lever, and then remove the intermediate choke rod from the air horn. 3. Drive back the roll pin at the upper end of the accelerator pump lever just enough to remove the lever, and then disconnect the pump rod and lever. 4. Disconnect and remove the accelerator pump rod and lever from the horn. 5. Hold the air valve wide open and then remove the secondary metering rods by tilting and sliding the rods from the holes in the hanger. 6. Remove the nine air horn-to-bowl attaching screws, 2 of the screws are counter-sunk next to the primary venturi. 7. Remove the retaining clip from the vacuum-break link at the vacuum- break diaphragm. Disconnect the vacuum-break link from the vacuum-break assembly. Gently push apart the retaining ears of the bracket to release the vacuum-break canister. 8. Now, lift straight up on the air horn and remove it, taking care not to bend the accelerator pump and air bleed tubes sticking out from the air horn. 9. Remove the piston from the air-valve link by rotating the bend through the hole, and then remove the from the air horn by rotating the bend through the air horn. Further disassembly of the air horn is not necessary. Do not remove the air valves, air valve shaft, and secondary metering rod hangers because they are calibrated. Do not attempt to remove the high-speed air bleeds and accelerating well tubes because they are pressed into position. Remove the accelerator pump piston from the pump well. Release the air horn gasket from the dowels on the secondary side of the bowl, and then pry the gasket from around the power piston and primary metering rods. Remove the pump return spring from the pump well. Pull off the insert block, remove the plastic filler from over the float valve. Use a pair of needle-nosed pliers and pull straight up on the metering rod hanger directly over the power piston and remove the power piston and the primary metering rods. Disconnect the tension spring from the top of each rod and then rotate the rod and remove the metering rods from the power piston. Pull up just a bit on the float assembly hinge pin until the pin can be removed by sliding it toward the pump well. 12. Insert a screwdriver into the slots on the fuel inlet seat and remove the seat and gasket. 13. Remove both primary metering rod jets. Remove the pump discharge check ball retainer and the check ball. 14. Remove the baffle plates from the secondary side of the bowl. 15. Disconnect the vacuum hose from the tube connection on the bowl and from the vacuum break assembly. Remove the retaining screw, and then lift the assembly from the float bowl. 16. Remove the fuel inlet filter retaining nut, gasket, filter, and spring. 17. Remove the throttle body by taking out the two throttle body-to-bowl attaching screws, and then lift off the insulator gasket. 18. Remove the idle mixture screws and springs. Take care not to damage the secondary throttle valves. CLEANING INSPECTION ERATE Never use a wire brush or drill to clean jet passages or tubes in the carburetor. Never allow the carburetor to soak in a cleaner bath for more than two hours. In fact, we recommend using spray cleaner. Never immerse the float assembly, needle, accelerator pump plunger or fuel filter in cleaner. Wipe them carefully with a clean cloth. Otherwise clean all allowable parts with carb cleaner and then dry with compressed air if at all possible. Blow out and through all passages to ensure there is no foreign material clogging them. Check the float needle and seat, if either is worn or damaged, replace them as a matched set. Check the float assembly and hinge pin for wear or damage, replace as necessary. Check the pump plunger, return spring, piston spring, idle mixture needle and all levers and linkages for wear or damage. Replace as necessary. Check the throttle valve shaft for excessive looseness in the throttle body. Check that the valve and shaft do not bind through their range of operation and that the valve opens and closes fully. Replace the assembly if it fails any of these tests. Check the choke valve lever and shaft for excessive looseness in the air horn. Check that the valve, lever and shaft do not bind through their range of operation and that the valve opens and closes fully. Replace the air horn assembly if it fails any of these tests. ASSEMBLY T I) See Figures 22, and 31 thru 42 1. Turn the idle mixture adjusting screws in until they are barely seated, and then back them out two to three turns as a rough adjustment at this time. Never turn the adjusting screws down tight into their seats or they will be damaged. 2. Place a new insulator gasket on the bowl with the holes in the gasket indexed over the two dowels. Install, and then tighten the throttle body-to- bowl screws evenly. 3. Install the fuel inlet filter spring, filter, new gasket, and inlet nut. Tighten the nut. 4. Install the baffle plates in the secondary side of the bowl with the notches facing up. 5. Grasp the choke rod so that the intermediate choke lever is at the bottom. Suspend the assembly into the float bowl so that the hole with the flat side aligns with the hole in the side of the float bowl. Now, insert the choke shaft on the vacuum break through the hole until it engages the flat- sided hole in the choke lever. lnstall the screw and tighten it securely. FUEL SYSTEMS -CARBURETORS ROD CHOKE HOLDER VALVE BREAK .EVER SHAFT , LEVER Flg. 22 Exploded view of a typical Rochester 4bbl carburetor FUEL SYSTEMS -CARBURETORS 8-13 Fig. 23 Remove the vacuum pump rod Fig. 24 Lift out the secondary metering rod I-Vacuum pump rod 2-valve 3-Air horn 4-Pump Lever Fig. 25 Lift the accelerator pump piston and spring out of the recess 1-Plastic filler 2-Primary metering rods 3-Power piston Fig. 26 Lift out the metering rods and power piston plate jets Fig. 27 Remove the primary jets and then remove the check ball retainer and ball nut Fig. 28 Remove the fuel inlet nut and associated Darts Primary jets Check ball Fig. 29 Removing the check ball Fig. 30 Lifting out the float 8-14 FUEL SYSTEMS -CARBURETORS Fig. 31 Suspend the choke lever into the float bowl ... 1-Choke rod 2-Choke lever 3-Flat sided hole Bend here Fig. 35 lnstalling the float assembly Fig. 36 Measuring the float Fig.34 Proper pull clip positioning Vacuum break 1 Choke rod Vacuum 2-Choke shaft break hose 3-Vacuum break control assembly Fig. 32 ...and then slide the vacuum break in Fig. 33 Installing the vacuum break until it engages the lever 6 lnstall the and gasket lnstall the pump passage next to the pump well 7 Install the pull on the needle the open end toward the front of the bowl lnstall the float by the float lever under the pull from the front to the back Hold the float assembly by the toe and the float lever the pull lnstall the from the pump well Take care not to the pull 8 Measure the from the top of the float bowl gasket surface, the gasket removed, to the top of the float at the toe end Check to be sure the held place and the tang of the float seated on the float needle when the measurement Check that your measurement 15164 If not, carefully bend the float up or down the correct measurement reached 9 lnstall the power the power well lnstall the meterlng jets, they were removed Be sure the connected to the top of each meterlng rod lnstall the assembly the well the meterlng jets, the should be flush the A sleeve around the plston holds the place assembly. lnstall the plastic filler over the float needle. Press it down firmly until it is seated. 2-Needle 3-Retaining pin I-Hinge pin 2-Universal carburetor gauge 3-Notch meterlng jets lnstall a new float needle seat check ball and In the 11. Place the accelerator pump return spring in the pump well. lnstall the air horn gasket around the primary metering rods and piston. lnstall the gasket on the secondary side of the bowl with the holes in the gasket indexed over the two dowels. lnstall the accelerating pump plunger in the pump well. 12. Install the secondary metering rods. Hold the air valve wide open and check to be sure the rods are positioned with their upper ends through the hanger holes and pointing toward each other. Hanger size may vary from the specifications chart due to inconsistencies in carburetor castings-the hole location may be different so make sure they are the same size as those originally installed. 13. Slowly position the air horn assembly on the bowl and carefully insert the secondary metering rods, the high-speed air bleeds, and the accelerating well tubes through the holes of the air horn gasket. Never force the air horn assembly onto the float bowl. Such action may distort the secondary metering plates. If the air horn assembly moves slightly sideways it will center the metering rods in the metering plates. lnstall the attaching screw. 14. Connect the pump rod to the inner hole of the pump lever and secure it with a spring clip. Position the lever into the casting mount on the carburetor and press the roll pin through the lever with a screwdriver. FUEL SYSTEMS -CARBURETORS 8-15 Fig. 37 Make sure the tension spring is positioned correctly before installing the power piston Power piston hanger 2-Tension spring 3-Metering rods Hanger 2-Metering rods Fig. 40 Positioning the secondary metering rods on the hanger 1-Plastic filler 2-Primary metering rods 3-Power piston Fig. 38 Installing the power piston and Fig. 39 Installing the float filler metering rods 2 1 Long Countersunk Fig. 41 Air horn tightening sequence Fig. 42 Use a screwdriver to press the roll pin place 15. Connect the bottom end of the choke shutter rod into the intermediate choke lever and secure it with a clip. Install the upper end of the rod into the choke blade lever and then press on the retaining clip. 16. Install the actuating rod into the air valve lever and then swivel the other end into the vacuum break arm and press on the retaining clip. Reconnect the vacuum line between the break and the carburetor. 17. Install the carburetor. ADJUSTMENT Accelerator Pump Rod See Figures 43 and 44 Back out the idle speed screw until it is no longer in contact with the throttle lever. 2. Move the pump rod to the inner hole on the lever if it's not already there. 3. Ensure that the throttle valves are closed fully and then measure the distance between the top of the carburetor (flame arrestor mounting surface) and the top of the pump plunger stem. Grasp the tip of the pump lever with a pair of needle nose pliers and bend it (carefully) until the distance is equal to Fig. 43 Measure the distance between the top of the carburetor and that listed in the Specifications chart while supporting the lever. the top of the plunger 1-Flame arrestor mounting surface 2-Pump plunger stem 8-16 FUEL SYSTEMS -CARBURETORS Choke Coil Rod + See Figures 45 and 46 1. Remove the flame arrestor. 2. Gently push the choke coil rod down into the housing. 3. The top of the choke coil rod must be even with the bottom of the hole in the vacuum break lever. 4. Bend the rod mid-way down at the kink to adjust it. Float Level See Figures 47 and 47 1. Press the float down lightly against the needle and hold the hinge pin in place securely. 2. Insert a float gauge (T-scale) into the hole near the flame arrestor stud. Measure from the top bowl casting to the top of the float at a point 3/16 in. in from the end of the float at the toe. 3. If not within specifications, bend the float arm with needle nose pliers at the location shown in the illustration. Speed Mixture Please refer to the Maintenance section for adjustment procedures. Vacuum Break + See Figures 48 and 49 4. Press in on the vacuum break control diaphragm until it is fully seated-attaching a small rubber band will sometimes help here. 5. Rotate the vacuum break choke lever counterclockwise until the left tang comes in contact with the vacuum break rod. The choke rod must be at the bottom of the slot in the choke lever. 6. Bend the tang on the choke lever until you can achieve the correct gap in the choke valve when checked with a drill bit between the inner wall of the air horn and the upper side of the valve. REMOVAL & INSTALLATION Always disconnect the battery cables before attempting to work on the fuel system. Never smoke or allow open flame near the engine--this sounds like an obvious precaution, but you'd be surprised at how many people forget! No matter how much they look alike, marine carburetors are completely different from automotive carburetors. Never substitute an automotive carburetor for the one on your engine! Venting procedures are not the same and an automotive carburetor could allow dangerous vapors to escape into the bilge. Don't even think about it. 1. Open the engine hatch or remove the covers and then disconnect the battery cables. Turn the fuel OFF shut down the fuel supply at the tank. 2. Remove the flame arrestor after disconnecting the vent hose. It's always a good idea to plug the throttle bores with a clean, lint-free cloth. 3. Unscrew the arrestor stud if the carburetor is to be replaced. 4. Pull out the cotter pin and disconnect the throttle cable at the carburetor and carefully move it out of the way. 5. Using two open-end wrenches, hold the fuel inlet nut at the carburetor securely and loosen the fuel line nut. Disconnect the two and carefully move the line out of the way. Plug both the inlet and line open ends to prevent fuel seepage. 6. Tag and disconnect the purpleiwhite electric choke lead. 7. Tag and disconnect any other lines, leads or hoses that may be in the way of removal. 8. Loosen and remove the 4 carburetor mounting and lift the unit off the manifold. Plug the opening with a clean lint-free cloth. Fig. 44 Bend the pump lever tip until the measurement is within specifications 1-Tip of pump lever 2-Support as shown Fig. 45 The top of the choke coil rod should be even with the bottom of the hole in the choke lever 1 Top of rod 2-Bottom of hole Fig. 46 Bend the choke coil rod here to adjust I-Bend here . FUEL SYSTEMS -CARBURETORS 8-17 Fig. 47 Read the float gauge where it intersects the top of the carburetor casing Fig. 47a Bend the float arm here Bend Pull Tang 2-Choke rod I Tang3-Vacuum break rod 2-Gap Fig. 48 Rotate the lever until the tang comes in contact with the Fig. 49 Measure the gap and then bend the tang to adjust vacuum break rod Remember which stud the flat washer and ground wire (from choke) were attached to. To Install: 9. Clean the mating surfaces thoroughly of all residual gasket material. 10. Position a new gasket and then install the carburetor. Position the flat washer and ground wire on the stud from which they were removed. Tighten the nuts to 10-14 (13-19 Nm). Hopefully you remembered to remove the rag! 11. Reconnect the fuel line to the inlet after removing the plugs and tighten it to 11-13 ft. Ibs. (15-18 Nm). Don't forget to use two wrenches. 12. Connect the choke lead. 13. Install and adjust the throttle cable. Install the flame arrestor and reconnect the vent line. 15. Connect the battery cables. Start the engine and ensure there are no fuel leaks; shut down the engine immediately if there are. Check and adjust the idle speed and mixture. DISASSEMBLY See Figures 50 thru 64 ERATE Disassembly can be made much easier by fabricating a holding fixture out of four 5116 x 2 in. bolts and eight nuts. Thread a nut about halfway onto each of the bolts, insert each one through the mounting holes on the carburetor and then screw on the remaining nuts. Voila, four little legs to keep your valuable carburetor off of whatever surface you are working on. Before even thinking about beginning this procedure, make certain that you have the correct rebuild kit for your make and model! 1. Remove the flame arrestor stud if you haven't already done this during removal. 2. Remove the fuel inlet line filter adapter from the float bowl. Lift out the filter screen and the 0-ring-throw away the O-ring. 3. Grab the spring clip retainer at the end of the choke plate lever and pull it off with a pair of needle nose pliers. 4. Remove the 3 Phillips screws from the thermostatic cover on the choke housing and lift off the retaining ring, the cover and the gasket. Make sure that you disengage the cover spring from the tang on the choke lever. 5. Remove the 3 Phillips screws, this time holding the choke housing to the main body. Pull off the housing while making sure that the choke linkage arm completely disengages from the horn linkage lever. 6. Turn over the carburetor and remove the 4 accelerator pump cover retaining screws at the bottom of the fuel bowl. Lift off the cover, its diaphragm and the spring. Make sure the inlet check ball moves freely. With the bowl still upside down and the check ball seated in the retainer, check that the clearance between the ball and retainer is in. If out of spec, bend the wire retainer very carefully to bring clearance back into range, Remember that this is not a serviceable item, so don't bend it too far, and don't remove the ball; otherwise you will need to replace the entire bowl. 7. Remove the four 5/16 in. primary fuel bowl retaining bolts and lift off the bowl and metering block assemblies. Discard the gaskets. You will most likely need to tap the assembly lightly with a small rubber mallet to break the seal. 8-18 FUEL SYSTEMS -CARBURETORS PIN Fia. 50 Exoloded view of a 23002 bbl carburetor Fia. 51 A good look at the fabricated mounting legs Make sure that you take note of the positioning of the wire on the end of the fuel valve and the metal tab on the float itself. This wire must hook UNDER the tab on reassembly or the inlet valve will not open during operation. On engines, remove the fuel inlet valve assembly. Loosen and remove the lock nut on the outer end of the float pin and then remove the inner hex nut and the two washers. Slide out the pin. Loosen the 2 screws holding the float and then remove it and the bracket. Fig. 52 Removing the fuel inlet and filter 9. On all other engines, pull off the float retainer (E-clip) with a pair of needle nose pliers the float off of the hinge pin. Remove the spring from the float (or pin) and then lift the baffle out of the bowl. Remove the inlet needle from its seat and then unscrew the seat, discarding the gasket. 10. When removing the float on all engines, the needle valve will fall into the bowl; make sure you remove it. Slide out the small plastic cover and unscrew the needle valve seat, pull out the gasket and discard it. 11. Remove the idle adjusting needles and their gaskets from the metering block (there should be one on each side of the block). It's never a bad idea to tighten them up while counting the turns until they make contact BEFORE you remove them as this will give you a decent benchmark for installation. 12. Remove the main jets with a screwdriver and then lift the vent baffle off of its pegs and throw away the two O-rings. 13. Unscrew the power valve with a FUEL SYSTEMS -CARBURETORS 8-19 Fig. 53 Pull out the spring clip ... Fig. 54 ...remove the choke housing cover... Fig. 55 ...and then remove the housing itself Fig. 56 Remove the accelerator pump cover, diaphragm and spring Fia. 57 Do not remove the check valve Fig. 58 Pull off the fuel bowl and its gasket in. wrench. Discard the gasket. 14. Remove all old gasket material from the metering block and the float bowl mating surfaces. 15. a small Phillips head screwdriver into the top of the carburetor and loosen the accelerator discharge nozzle so that you can pull out the nozzle. Make sure you get both gaskets out. 16. Turn the carburetor over (the discharge needle should fall out while you're doing this) and remove the 6 throttle body retaining screws and washers. Disconnect the vacuum hose from the choke and then lift off the throttle body. 17. Further disassembly should be unnecessary. CLEANING INSPECTION Never use a wire brush or drill to clean jet passages or in the carburetor. Check the float needle and seat, if either is worn or damaged, replace them as a matched set. Check the float assembly and hinge pin for wear or damage, replace as necessary. Check the pump plunger, return spring, piston spring, idle mixture needle and all levers and linkages for wear or damage. Replace as necessary. Check the throttle valve shaft for excessive looseness in the throttle body. Check that the valve and shaft do not bind through their range of operation and that the valve opens and closes fully. Replace the assembly if it fails any of these tests. Check the choke valve lever and shaft for excessive looseness in the air horn. Check that the valve, lever and shaft do not bind through their range of operation and that the valve opens and closes fully. Replace the air horn assembly if it fails any of these tests. ASSEMBLY 4 See Figures 50 thru 64 and 65 Please refer to the Disassembly section for additional illustrations of the assembly procedure. Never allow the carburetor to soak in a cleaner bath for more than two hours. In fact, we recommend using spray cleaner. Never immerse the throttle body, float assembly, needle, accelerator pump plunger or fuel filter in cleaner. Wipe them carefully with a clean cloth. Otherwise clean all allowable parts with carb cleaner and then dry with compressed air if at all possible. Blow out and through all passages to ensure there is no foreign material clogging them. 1. Position a new gasket over the bottom of the main body so that all six holes line up correctly. Install the throttle body and screws and tighten them to 50 inch Ibs. (5.6 Nm). 2. Drop the accelerator pump discharge needle into its bore in the body. Slide a new gasket over the nozzle screw, followed by the nozzle and another new gasket. Now install the nozzle so that the notches on its body align with those in the bore and tighten the screw to 15 inch Ibs. (1.7 Nm). 3. Manv rebuild kits will contain more than one oower valve-check the number in the Carburetor specifications chart for your engine -- and make sure you grab a valve with the corresponding number stamped on it. Now look at the fuel ports on the valve. A valve with multiple fuel passages will require a gasket with three internal projections; while a valve with only two passages will require a gasket without any internal projections and a round gasket. Make sure you choose the correct one. Install the valve into the metering block and tighten it to 100 inch 8-20 FUEL SYSTEMS -CARBURETORS Fig. 59 A good look at the float assembly in the bowl Fig. 60 Slide out the plastic cover Fig. 61 Removing the metering block from the main body Fig. 62 Unscrewing the power valve Fig. 63 Remove the accelerator discharge Fig. 64 The throttle body is attached to the bottom of the main body Fig. 65 Most power valves will be marked with an identifier-this one is a 4.5 (11.3 Nm). In some cases, but not all, if you're working on a you've probably already figured out by now that you don't have a power valve. 4. Slide new O-rings over each end of the vent baffle, coat them lightly with engine oil and insert one end into the block. Install the jets. 5. Install a new gasket onto each of the idle mixture needles. Screw them until they just seat on the block and then back them out an equivalent number of turns as noted on removal. 6. Coat the inner mating surface of the metering block with a very thin film of grease and position a new gasket over the dowels. Position the block and gasket onto the carburetor and press it into place. 7. Position a new gasket (metal) onto the needle valve seat and then tighten it into the fuel bowl to 10 inch Ibs. Nm). Slide the small cover into position. Place a new needle valve into the seat so that the spring clip faces out. 8. Slide the float onto the hinge pin, making sure that the clip rides over the float tab. Position the float spring into the grooves on the bowl and then install the small e-clip retainer onto the hinge pin. 9. Turn over the fuel bowl so the float tab is resting on top of the needle valve. If the float is not level (parallel to the bowl), carefully bend the tab until it is. 10. Position the diaphragm spring into the accelerator pump cavity. Lay a new diaphragm over the spring so the raised disc is facing up and resting on the pump lever. Install the cover over the diaphragm and tighten the screws securely. 11. Coat the outer mating surface of the metering block with a very thin film of grease and position a new gasket over the dowels. Position the bowl onto the block and press it into place. lnstall the mounting bolts, with new gaskets, until each is just finger-tight. Now tighten them again to 45 inch Ibs. 1 12. Check that the choke lever, spring and piston all move smoothly with no sign of binding, Squeeze a drop of light weight oil into the piston bore and actuate the piston several times. Choke components are not available individually-if you detect problems, replace the entire assembly. 13. Position the choke assembly on the main body so that the choke plate lever and the choke lever align. Tighten the 3 screws securely. FUEL SYSTEMS -CARBURETORS 14. Insert a new cover gasket over the housing so the piston is protruding through the gasket. Now install the cover while guiding the lever into the spring end. Make sure that the lever engages the spring or the choke will be useless. Rotate the cover until the index mark is in the same place as noted during removal (or, check the Specifications chart). Slide on the retaining ring and then tighten the screws securely. The ring has raised tabs at each hole to aid in pulling the cover in tight; if after tightening the 3 screws you notice that the cover is still loose, remove the screws and flip the retaining ring over. 15. Install the spring clip over the choke plate lever, securing it to the choke lever. 16. Insert a new (or cleaned) fuel filter screen into the adapter, thread the assembly into the fuel bowl and tighten it to 100 inch Ibs. (11.3 Nm). 17. Thread the flame arrestor stud into the top of the unit, tightening it securely. Remove the fabricated legs if you haven't already and then install the carburetor. Check the throttle cable and idle speed adjustments. ADJUSTMENT Float Level Engines attempting to perform this procedure without removing the carburetor, please make certain that you first drain all fuel from the carburetor. Remove the fuel bowl as detailed in the Carburetor Disassembly section. 2. Turn the bowl upside down and loosen the float adjustment screw. 3. Turn the adjustment nut until the float is sitting level in the bowl. 4. Hold the nut and tighten the screw securely. 5. the fuel bowl. All Other Engines See Figure 66 If attempting to perform this procedure without removing the carburetor, please make certain that you first drain all fuel from the carburetor. 1. Remove the fuel bowl as detailed in the Carburetor Disassembly section. 2. Remove the float baffle and then turn the bowl upside down. 3. Carefully bend the curved float arm that comes in contact with the inlet needle until the float is level and parallel with the fuel bowl. 4. Install the fuel bowl. Accelerator Pump Stroke Accelerator pump stroke is controlled by the position of the cam. The mounting screw must be positioned in the correct hole in the cam and throttle arm as detailed in the Carburetor Specifications chart. Fig. 66 Bend the arm to adjust the float level Accelerator Pump Clearance Remove the flame arrestor. 2. Move the throttle plates to the wide open position and hold there. 3. Depress the pump arm and then check the clearance between the arm (still depressed) and the head of the pump lever screw. 4. If clearance is not within the specifications detailed in the chart, rotate the adjusting screw IN to increase the clearance, or OUT to decrease 5. Check the pump operation; the pump should begin to move immediately when moving the throttle shaft. Any indication of hesitation on the pump's part will lead to hesitation or lag felt when using the throttle. Check for bent or worn components. Recheck you clearance adjustment and then check the pump stroke. 6. Install the flame arrestor. Choke Vacuum See Figures 67 and 68 Remove the flame arrestor. 2. Remove the 3 retaining screws and lift off the choke housing cover and retaining ring. 3. Using a paper clip or very small awl, press the choke piston down against the screw stop. 4. While holding the piston down against the stop, apply light pressure to the choke housing lever (as if you were closing it) until all free play is removed from the linkage. 5. Now insert the correct size drill bit into the choke opening and adjust it with the stop screw-tighten the screw to decrease the opening size and loosen it to increase the size of the opening. Be careful if you are increasing the size of the opening with the screw. Never back the screw out so far as to let the piston slip past it. 6. Reinstall the housing cover as detailed in the Carburetor Assembly procedures. Install the flame arrestor. Fig. 67 Push the piston against the screw stop with a paper clip 8-22 FUEL SYSTEMS -CARBURETORS 68 Choke vacuum adiustment screw Choke Unloader Remove the flame arrestor. 2. With the throttle valves held in the wide open position, carefully insert the correct drill bit (see the Spec chart) between the lower edge of the plate and the inner wall of the air horn. 3. Now press lightly on the choke control lever while removing the bit. You should notice a very light drag on the bit as you are pulling it out. If not, or if you feel heavy pressure, use needle nose pliers to bend the tab on the throttle shaft lever (behind the choke housing) until you are satisfied with the drag. REMOVAL INSTALLATION 9. If replacing the carburetor, take note of the throttle lever bracket position and remove it. To Install: 10. Clean the mating surfaces thoroughly of all residual gasket material. 11. Attach the throttle lever bracket from the old carburetor making sure its in the same position as on the original one. 12. Position a new gasket and then install the carburetor. Position the flat washer and ground wire on the stud from which they were removed. Tighten the nuts to ft. Ibs. (13-19 Nm). Hopefully you remembered to remove the rag! 13. Reconnect the fuel line to the inlet line after removing the plugs and tighten it to 11-13 ft. Ibs. (15-18 Nm). Don't forget to use two wrenches. Don't forget to reinstall the vent hose on the engine. 14. Connect the choke lead. 15. Install and adjust the throttle cable. 16. Install the flame arrestor stud and tighten it to 65-80 inch Ibs. (7.3-9 Nm). 17. Install the flame arrestor and reconnect the vent line. 18. Connect the battery cables. Start the engine and ensure there are no fuel leaks; shut down the engine immediately if there are. Check and adjust the idle speed and mixture. DISASSEMBLY CULT See Figures 69 thru 77 Disassembly can be made much easier by fabricating a holding fixture out of four 5116 x 2 in. bolts and eight nuts. Thread a nut about halfway onto each of the bolts, insert each one through the mounting holes on the carburetor and then screw on the remaining nuts. Voila, four little legs to keep your valuable carburetor off of whatever surface Always disconnect the batt ery cables before attempting to work on the fuel system. Never smoke or allow open flame near the No matter how much they look alike, marine carburetors are completely different from automotive carburetors. Never substitute an automotive carburetor for the one on your engine! Venting procedures are not the same and an automotive carburetor could allow dangerous vapors to escape into the bilge. Don't even think about it. Open the engine hatch or remove the covers and then disconnect the battery cables. Turn the fuel OFF shut down the fuel supply at the tank. 2. Remove the flame arrestor after disconnecting the vent hose. It's always a good idea to plug the throttle bores with a clean, lint-free cloth. 3. the arrestor stud if the carburetor is to be replaced. 4. Pull out the cotter pin and disconnect the throttle cable at the carburetor and carefully move it out of the way. 5. Using two open-end wrenches, hold the fuel inlet nut at the carburetor securely and loosen the fuel line nut. Disconnect the two and carefully move the line out of the way. Plug both the inlet and line open ends to prevent fuel seepage. On Ford engines, cut the plastic tie and remove the vent hose. 6. Tag and disconnect the electric choke lead. 7. Tag and disconnect any other lines, leads or hoses that may be in the way of removal. 8. Loosen and remove the 4 carburetor mounting and lift the unit off the manifold. Plug the opening with a clean lint-free cloth. Remember which stud the flat washer and ground wire (from choke) Before even thinking about beginning this procedure, make certain that vou have the correct rebuild kit for make and model! 1. Remove the flame arrestor stud if you haven't already done this removal. 2. Remove the four primary fuel bowl retaining bolts and lift off the bowl aside. You will most likely need to tap the bowllblock assembly lightly with a small rubber mallet to break the seal. 3. Pull the transfer tube out of the inner side of the carburetor mating surface and discard the O-rings. 4. Remove the idle adjusting needles and their gaskets from the metering block (there should be one on each side of the block). It's never a bad idea to tighten them up while counting the turns until they make contact BEFORE you remove them as this will give you a decent benchmark for installation. 5. Remove the main jets with a jet wrench (a screwdriver should work here as well) and then lift the vent baffle off of its pegs and throw away the two O-rings. Make sure that you take note of the jet numbers and which bore they came out of. Fig. 69 A good look at the fabricated mounting legs were attached to. FUEL SYSTEMS -CARBURETORS 8-23 COVER 70 Exploded view of a typical 41501416014175 bbl carburetor 8-24 FUEL SYSTEMS -CARBURETORS Fig. 71 Unscrewing the power valve Block 6. Unscrew the power valve from the inner side of the metering block with a Iin. wrench. discard the gasket. Pull out the accelerator pump tube and discard the O-rings. 7. Working inside the primary bowl, pull off the float retainer (E-clip) with a pair of needle nose pliers and slide the float off of the hinge pin. Remove the spring from the float (or pin) and then lift the baffle (small plastic cover) out of the bowl. Remove the inlet needle from its seat and then unscrew the seat, discarding the gasket. The needle valve will probably fall into the bowl; make sure you remove it. 8. Turn over the bowl and remove the 4 accelerator pump cover retaining screws at the bottom of the fuel bowl. Lift off the cover, its diaphragm and the spring. Make sure the inlet check ball moves freely. With the bowl still upside down and the check ball seated in the retainer, check that the clearance between the ball and retainer is 0.011-0.013 in. If out of spec, bend the wire retainer very carefully to bring clearance back into range, Remember that this is not a serviceable item, so don't bend it too far, and don't remove the ball; otherwise you will need to replace the entire bowl. 9. Remove the fuel inlet line filter adapter from the float bowl. Lift out the filter screen and the 0-ring-throw away the O-ring or gasket. 10. Remove any and all remaining gasket material from the bowl and block mating surfaces. 11. Remove the secondary fuel bowl and metering block by following the procedures above for the primary. Note that there will be no accelerator pump or power valve to remove here. Note also that if you are working on a V8 engine, you will probably need a 122 clutch-type screwdriver to remove the 4 bowl retaining screws. 12. Pull off the retaining clip at the bottom of the secondary vacuum diaphragm link rod. 13. Turn the carburetor over and remove the throttle body retaining screws and washers. 14. Pull the retaining clip off of the lower end of the choke rod with needle nose pliers. Remove the 3 retaining screws and lift off the choke housing cover and retaining ring. Now you can remove the 3 housing retaining screws and pull off the housing and vacuum passage gasket. 15. Remove the secondary vacuum housing from the main body-you should have disconnected the link rod in an earlier step. Remove the four cover screws and lift off the cover, spring, diaphragm and check ball from the housing. 16. Insert a small Phillips head screwdriver into the top of the carburetor and loosen the accelerator discharge nozzle so that you can pull out the nozzle. Make sure you get both gaskets out. Turn over the carburetor and let the needle fall into your hand. Fig. 75 ...the cover and diaphragm spring ... Fig. 73 Do not remove the check valve Fig. 76 ...and the diaphragm itself Fig. 74 Remove the secondary diaphragm rod circlip ... Fig. 72 Remove the accelerator pump cover, diaphragm and spring Fig. 77 Remove the accelerator discharge nozzle from inside the bore FUEL SYSTEMS -CARBURETORS 8-25 Unless there is damage, do not remove the choke plate, shaft, rod or guide. The plate screws are staked and must be filed down to the shaft in order to remove anything. 17. Further disassembly should be unnecessary. CLEANING & INSPECTION See Figures 78 and 79 Never use a wire brush or drill to clean jet passages or tubes in the carburetor. Never allow the carburetor to soak in a cleaner bath for more than two hours. In fact, we recommend using spray cleaner. Never immerse the throttle body, float assembly, needle, accelerator pump plunger or fuel filter in cleaner. Wipe them carefully with a clean cloth. Otherwise clean all allowable parts with carb cleaner and then dry with compressed air if at all possible. Blow out and through all passages to ensure there is no foreign material clogging them. Check the float needle and seat, if either is worn or damaged, replace them as a matched set. Check the float assembly and hinge pin for wear or damage, replace as necessary. Check the pump plunger, return spring, piston spring, idle mixture needle and all levers and linkages for wear or damage. Replace as necessary. Check the throttle valve shaft for excessive looseness in the throttle body. Check that the valve and shaft do not bind through their range of operation and that the valve opens and closes fully. Replace the assembly if it fails any of these tests. Fig. 79 Check the secondary vacuum diaphragm (top) and the accelerator pump diaphragm for tears, pin holes or other damage Check the choke valve lever and shaft for excessive looseness in the air horn. Check that the valve, lever and shaft do not bind through their range of operation and that the valve opens and closes fully. Replace the air horn assembly if it fails any of these tests. Always replace the seat valve assemblies. These components receive the most wear of any part in the carburetor and correct fuel level cannot be maintained if they are worn or damaged. Check the secondary vacuum diaphragm by depressing the diaphragm stem and covering the vacuum fitting with your finger. Release the stem; if it moves out more than 1116 in. in ten seconds, there is a leak and it will require replacement. 78 Always replace the seat valves ASSEMBLY CULT See Figures 69 thru and 81 Please refer to the Disassembly section for additional illustrations of the assembly procedure. Drop the accelerator pump discharge needle into its bore in the throttle throat. Position the nozzle over the needle so that the nozzles are down and the slot is air'vent rib; install the retaining screw and tighten it securely. 2. Drop the check ball into the hole in the secondary vacuum diaphragm housing and then insert the diaphragm into the housing so that the vacuum hole lines up with the opening for the check ball. It's a good idea to squirt a drop of clean oil under each of the four corners on the diaphragm to keep it from moving when installing the cover. Place the spring onto the housing cover and then install the cover so that all screw and vacuum holes are in alignment. Tighten the cover screws securely while holding the diaphragm rod to keep the diaphragm from collapsing. 3. Position a new gasket over the secondary vacuum passage on the carburetor body and then install the housing onto the carburetor. Tighten the screws securely. 4. Position a new choke housing gasket on the carburetor. Install the housing while guiding the housing shaft lever onto the choke rod. The projection on the end of the choke rod must be under the fast idle cam so that the cam will be raised whenever the choke plate is closed. Tighten the mounting screws and lock washers and then slip the retaining clip onto the choke rod. 5. Install the choke housing cover with a new gasket. The small lever attached to the choke piston MUST index into the loop on the thermostatic coil. Position the retaining ring over the cover and then install the mounting screws finger-tight. Rotate the cover so that the index marks on the cover and housing line up as they were before removal; or check the Specifications chart. Tighten the screws. 6. Turn over the carburetor and install a new throttle body gasket. Position the throttle body while sliding the secondary vacuum diaphragm rod over operating lever. Tighten the mounting screws to 50 inch Ibs. (5.6 Nm) and then press the retainer onto the diaphragm rod and operating lever. 7. Position a new gasket onto the fuel inlet nut, install the nut and tighten it securely. 8-26 FUEL SYSTEMS -CARBURETORS 8. Position the spring into the accelerator pump bore on the primary fuel bowl and then install the diaphragm so that the large end of the lever disc will be against the operating lever. lnstall the cover and tighten the screws securely. Move the operating lever so that it compresses the diaphragm to ensure that it has not been pinched and then tighten the cover screws to 5 inch Ibs. (0.6 Nm). 9. On all models but the Ford, insert the filter screen into the primary bowl and then install the inlet nut with a new gasket. On the engine, install the inlet nut and filter with a new gasket. 10. Thread the fuel inlet needle seat into the bore with a new gasket. Drop in the needle and clip assembly and slide the plastic baffle into position. 11. Position the float into the bosses and then slide in the guide pin. Check the float setting as detailed in the Adjustments section. 12. Many rebuild kits will contain more than one power valve--check the number designated in the Carburetor Specifications chart for your engine and make sure you grab a valve with the corresponding number stamped on it. Now look at the fuel ports on the valve. A valve with multiple fuel passages will require a with three internal proiections; while a valve with two require a gasket internal projections and round aasket. Make sure vou choose the correct one. lnstall the valve into the block and tighten it to 100 inch (11.3 Nm). 13. Coat two new O-rings with clean engine oil and slide them onto the transfer tube. Press the tube into the primary metering block until it is fully seated. 14. Thread the main jets into their original bores. Remember that all jets should be marked with an individual number-refer to the Specifications chart for this number. 15. lnstall new gaskets on the idle mixture needles and then thread them into the block until they just come into contact with the surface and then back them out an equivalent number of turns to the figure recorded during the disassembly procedure; or check the Specification chart. 16. Coat the inner mating surface of the metering block with a very thin film of grease. Position a new gasket over the dowels. Position the block and gasket onto the carburetor and press it into place. 17. Coat the outer mating surface of the metering block with a very thin film of grease and position a new gasket over the dowels. Position the baffle plate. Make sure that the accelerator passages are not blocked and position the bowl onto the block and press it into place. lnstall the mounting bolts, with new gaskets, until each is just finger-tight. Now tighten them again to 45 inch (5.1 18. Coat two new tube O-rings with Vaseline and slide them onto the so thev're aaainst the flanae on each end. Press one end into the recess'in the bowl careful disturb the O-ring. 19. Assemble the secondary fuel bowl and metering block by following the procedures above for the primary. Note that there will be no accelerator pump or power valve to assemble here so skip those steps. Fig. 80 The small lever MUST engage the loop in the housing cover 20. After assembling all components associated with secondary bowl and metering block, position a new gasket over the dowels on the inner side of the metering block. Now position the metering plate and another inner gasket on the block and attach the assembly to the carburetor, lnstall the retaining screws and tighten them securely. 21. Position the bowl over the block and then install it so that the fuellbalance tube slides into the recess. lnstall and tighten the retaining screws. Note also that if you are working on a V8 engine, you will need a clutch-tvoe screwdriver to remove the 4 bowl retainina screws. 22. the carburetor. Fig. 81 Most power valves will be marked with an identifier-this one is a 4.5 ADJUSTMENT If the carburetor has been rebuilt, please perform all adjustments in the following order; otherwise perform individual adjustments as necessary. Throttle Valve Plate See Figure 82 The carburetor must be removed for this adjustment. 1. Remove the carburetor and turn it upside down. Carefully set it down on a clean surface. 2. Back out the secondary throttle shaft stop screw until the secondary throttle plates are fully closed. This screw is imbedded in the throttle body, just underneath the secondary vacuum diaphragm rod. 3. Snap the throttle plates closed, turn the stop screw in until it just comes into contact with the secondary lever and then turn the screw in another 114 of a turn. The plates should not stick in the bores-if they do, turn in the screw slightly until they stop sticking. 4. lnstall the carburetor. Float Level ERA See Figure 83 Primary and secondary fuel bowls are both adjusted in the same manner. Which one you start with is up to you. 1. Drain the fuel from the carburetor and then remove the fuel bowl and float assembly as detailed in the Disassembly procedures. Although not necessary, we recommend removing the carburetor. 2. Remove the float baffle and then turn the bowl upside down. 3. Carefully bend the curved float arm contacting the float inlet needle until the edge of the float is parallel with the edge of the fuel bowl. 4. lnstall the bowl with new gaskets. lnstall the carburetor if removed. FUEL SYSTEMS -CARBURETORS Fig. 82 Use a small screwdriver to turn the stop screw Fia. 83 Bend the float arm here Choke Vacuum Qualification See Figures 84 and 85 Remove the choke housing and retaining ring. 2. Unbend a paper clip, insert it into the piston bore and push the piston down until it rests against the screw stop. Be careful that you do not scratch the piston or bore. 3. With the piston still against the stop, apply very light pressure to the choke housing lever in the closed position until all free-play has been removed from the linkage. 4. Refer to the Carburetor Specifications chart, and insert the correct size drill bit between the lower edge of the plate and the inner wall of the air horn. Tighten the screw stop to decrease clearance, or loosen the screw to increase clearance. The drill bit must slide through the opening with no drag. Never back the screw out so far as to allow the piston to drop past the screw. Accelerator Pump Stroke Accelerator pump stroke if fully controlled by the position of the cam-which is to say, the hole it is in on the throttle arm. Please refer to the Carburetor Specifications chart for the correct hole. Accelerator Pump Clearance 1. Move the throttle to the wide open position and hold lever down. 2. Insert a 0.0015 in. flat feeler gauge between the bolt head under the pump lever and the pump arm. Turn the adjuster screw until you can obtain the correct clearance; turn it in to increase the clearance, or out to decrease the clearance. 3. The pump should begin to move as soon as the throttle shaft moves. Fig. 84 Carefully force the piston down with a paper clip 8-28 FUEL SYSTEMS -CARBURETORS 85 Choke vacuum adiustment screw stop Automatic Choke See Figure 86 The electric automatic choke has been set at the factory to give maximum performance under all operating and weather conditions. marks on the cover and housing should be aligned as specified in the Carburetor Specifications chart. A richer or leaner mixture can be obtained by loosening the cover screws and rotating the housing cover. Rotating the housing cover in a counterclockwise direction will the mixture, causing the choke to stay on for a longer time. Rotating the housing cover in the clockwise direction will lean out the mixture, causing the choke to kick off sooner. It is a aood idea to always keep alternative within two notched of the . . setting. Fig. 86 Aligning the index marks will set the automatic choke for proper operation Choke Unloader Refer to the Carburetor Specifications chart for the proper size drill bit to use. Hold the throttle in the wide open position and insert the appropriate drill bit between the upper edge of the plate and the inner wall of the air horn. This will actually give the proper clearance at the lower edge of the plate. Place you finger on the choke control lever and check that you can feel a very slight drag as the drill bit is moved through the opening. Carefully bend the tab on the kick down lever (under the housing) with needle nose pliers until the correct clearance is achieved and the drill bit passes through the opening with a slight drag. DESCRIPTION See Figures and 91 A mechanical-type fuel pump driven off the camshaft is utilized on all and engines, 1984-91 engines, 1986-92 GM engines and all carbureted V8 Ford engines. The fuel pump sucks gasoline from the fuel tank and delivers it to the carburetor in sufficient quantities, under pressure, to satisfy engine demands under all operating conditions. The pump is operated by a two-part rocker arm. The outer part rides on an eccentric on the camshaft and is held in constant contact with the camshaft by a strong return spring. The inner part is connected to the fuel pump diaphragm by a short connecting rod. As the camshaft rotates, the rocker arm moves up and down. As the outer part of the rocker arm moves downward, the inner part moves upward, pulling the fuel diaphragm upward. This upward movement compresses the diaphragm spring and creates a vacuum in the fuel chamber below the diaphragm. The vacuum causes the outlet valve to close and fuel from the tank to enter the chamber by way of the fuel filter and the inlet valve. Now, as the eccentric on the camshaft allows the outer part of the rocker arm to move upward, the inner part moves downward, releasing its hold on the connecting rod. The compressed diaphragm spring then exerts pressure on the diaphragm, which closes the inlet valve and forces fuel out through the outlet valve to the carburetor. GASKET PLATE Fig. 87 Exploded view of the fuel pump1986- 90 and enaines FUEL Fig. 88 Exploded view of the fuel I I PLATE engines, enaines and all GM enaines FUEL SYSTEMS -CARBURETORS 8-29 Fig. 90 Exploded view of the fuel pump-1995-98 engines Fig. 89 A good shot of the pump on a 1993-94 engine Fuel Line Gasket , Overflow Hose Fig. 91 Exploded view of the fuel pump--Ford V8 engines Elbow Because the fuel pump moved downward only by the diaphragm spring, the pump delivers fuel to the carburetor only when the pressure in the outlet line is less than the pressure exerted by the diaphragm spring. This lower pressure condition exists when the carburetor float needle valve is unseated and the fuel passages from the pump into the carburetor float chamber are open. When the needle valve is closed and held in place by the pressure of the fuel on the float, the pump builds up pressure in the fuel chamber until it overcomes the pressure of the diaphragm spring. This pressure almost stops of the diaphragm until more fuel is needed in the carburetor float bowl. REMOVAL INSTALLATION All Except Ford V8 Engines See Figures 87 thru 90 Always have a fire extinguisher handy when working on any part of the fuel system. Remember, a very small amount of fuel vapor in the bilge, has the tremendous potential explosive power. Open or remove the engine hatchlcovers. Disconnect the battery cables. 2. Position a container under the and remove the fuel inlet and outlet lines. It is important to use two wrenches; one to hold the fitting nut and the other to loosen the line nut. Plug the line with a golf tee or something similar to prevent additional fuel spillage. Take care not to spill fuel on a hot engine, because such fuel may ignite. If your boat has a fuel shut-off valve, make sure it is turned OFF before disconnecting the fuel lines. 3. Disconnect the sight tube on engines so equipped. 4. Cut the plastic tie and pull off the line. 5. On the engine, you may find that removing the starboard engine mount will be beneficial on many engines-you can be the judge by observing the working space. 6. Loosen the two pump mounting boltsllock washers and carefully pull the pump out. Scrape any old gasket material from the pump and block mating surfaces. The pump may fall out of position when removing the pump; to prevent this, slip a small screwdriver in behind the pump and support the 7. Take note of the pump elbow positioning and then remove it for use on a new pump. To Install: 8. Check the pump for damage or wear. 9. Coat the threads of the elbow with Teflon@ Pipe sealant-DO NOT use Teflon@ tape. Install the elbow to the pump and tighten it to 48-60 inch Ibs. (5.4-6.7 Nm). 10. Coat BOTH sides of the new gasket with Gasket Sealing compound and position it on block. Swab the end of the with grease and insert the pump into the cylinder block so that the rod is riding on the camshaft eccentric. Tighten the mounting bolts to 12-14 ft. Ibs. (16-19 Nm) on and 1986-90 engines; 20-25 ft. Ibs. (27-34 Nm) on and engines and 1991 -98 engines. 11. Connect the vent line and tie it into position. 12. Coat the threads of the fuel line pump fittings with Pipe Sealant, thread them into the pump base and then tighten to 15-18 ft. Ibs. (20-24 Nm) while holding the inlet fittings with another wrench. Do not over-tighten and do not use Teflon tape. 13. Install the sight tube if removed. 14. Install the engine mount if removed. Don't forget to check the engine alignment. 15. Remove the container and connect the battery cables. Start the engine and check for fuel leaks. FUEL SYSTEMS -CARBURETORS Ford Engines 4 See Figures 91 and 92 Always have a fire extinguisher handy when working on any part of the fuel system. Remember, a very small amount of fuel vapor in the bilge, has the tremendous potential explosive power. Open or remove the hatchlcovers. Disconnect the battery cables 2. Unscrew and remove the fuel inlet line at the fuel Unscrew the filter and remove it 3 a under the pump and remove the fuel and outlet It important to use two open-end wrenches, one to hold the and the other to loosen the nut Plug the with a golf tee or to prevent fuel Take care not to spill fuel on a hot engine, because such fuel may If your boat has a fuel shut-off valve, make sure it is turned OFF before disconnecting the fuel lines. 4 Cut the and pull off the vent 5. Remove the two bolts and off the fuel bracket, of the way 6. Loosen the two pump screwsllock washers and carefully pull the pump out Scrape any old gasket from the pump and block surfaces The pump may fall out of when the pump, to prevent slip a small in the pump and support the 7 Take note of the pump elbow and then remove on a new pump. for use To Install: 8. Check the pump for damage or wear 9. Coat the threads of the elbow with Teflon@ sealant-DO NOT use Teflon@ tape. Install the elbow to the pump and to 48-60 Ibs. (5.4-6.7 . . 10. Coat BOTH sides of the new gasket with Gasket Sealing compound and it on block. Swab the end of the with arease and insert the into the cylinder block so that the rod is riding camshaft eccentric. Tighten the mounting bolts to 18-20 ft. Ibs. (24-27 Nm). 11. Install the filter bracket and tighten the bolts to 20-25 ft. (27-34 Fig. 92 A good shot of the fuel pump 12. Connect the vent line and tie it into position. 13. Coat the threads of the fuel line pump fittings with Pipe Sealant, thread them into the pump base and then tighten to 15-18 ft. Ibs. (20-24 while holding the inlet fittings with another wrench. Do not over-tighten and do not use Teflon tape. lnstall the filter and then reconnect the inlet line. 15. Remove the container and connect the battery cables. Start the engine and check for fuel leaks. Ford Engines 4 See Figures 91 and 93 Always have a fire extinguisher handy when working on any part of the fuel system. Remember, a very small amount of fuel vapor in the bilge, has the tremendous potential explosive power. 1. Open or remove the engine hatchlcovers. Disconnect the battery cables. 2. Unscrew and remove the fuel inlet and outlet lines at the fuel filter. On early models, you will need to drain the engine oil and then remove the oil filter to gain access here. 3. Unscrew and remove the filter fuel line at the fuel pump and remove it. 4. Remove the bolt, lock washer and plaster nut securing the dipstick clamp to the filter bracket. Remove the 2 mounting bolts and then lift off the bracket and filter. Carefully set it down upright as there will be fuel in the filter. 5. Position a container under the pump and remove the remaining fuel outlet line. It is important to use two open-end wrenches; one to hold the fitting and the other to loosen the line nut. Plug the line with a golf tee or something similar to prevent additional fuel spillage. Take care not to spill fuel on a hot engine, because such fuel may ignite. If your boat has a fuel shut-off valve, make sure it is turned OFF before disconnecting the fuel lines. 6. Cut the plastic tie and pull off the vent line. 7. Remove the two mounting bolts and lift off the fuel filter bracket, securing it out of the way. 8. Loosen the two pump mounting boltsllock washers and carefully pull the pump out. Scrape any old gasket material from the pump and block mating surfaces. The pump may fall out of position when removing the pump; to prevent this, slip a small screwdriver in behind the pump and support the 9. Take note of the pump elbow positioning and then remove it for use on a new pump. To Install: 10. Check the pump for damage or wear. 11. Coat the threads of the elbow with Teflon@ Pipe sealant-DO NOT use tape. lnstall the elbow to the pump and tighten it to 48-60 inch Ibs. (5.4-6.7 Nm). 12. Coat BOTH sides of the new gasket with Gasket Sealing compound and position it on block. Swab the end of the with grease and insert the pump into the cylinder block so that the rod is riding on the camshaft eccentric. Tighten the mounting bolts to 20-25 ft. Ibs. (27-34 Nm). 13. Connect the vent line and tie it into position. 14. Thread the pump outlet line in and tighten the line nut securely. 15. lnstall the filter and bracket and tighten the bolts finger-tight. Make sure that the long bolt goes in the upper hole. 16. lnstall the dipstick tube clamp and tighten it securely. Now go back and tighten the bracket mounting bolts to ft. Ibs. (27-34 Nm). 17. Coat the threads of the remaining fuel line fittings with Pipe Sealant, thread them into the pump base and then tighten to 15-18 ft. Ibs. (20-24 Nm) while holding the fittings with another wrench. Do not over-tighten and do use Teflon tape. 18. lnstall the oil filter if removed. 19. Remove the container and connect the battery cables. Start the engine and check for fuel leaks. FUEL SYSTEMS -CARBURETORS 8-31 Fig. 93 A good shot of the fuel pump Always have a fire extinguisher handy when working on any part of the fuel system. Remember, a very small amount of fuel vapor in the bilge, has the tremendous potential explosive power. 1. Open or remove the engine hatchicovers. Disconnect the battery cables. 2. Confirm that there is fuel in the tank. Also, make sure that the fuel filter and the carburetor inlet filter are clean and free of obstructions. 3. Position a container under the fuel filter and remove the inlet line. It is important to use two open-end wrenches; one to hold the fitting elbow and the other to loosen the line nut. Plug the line with a golf tee or something to prevent additional fuel spillage. 4. Tag and disconnect all electrical leads at the (t)terminal of the ignition coil; tape the ends and position them out of the way. Reconnect the battery cables. 5. Connect a vacuum gauge to the remaining fitting on the connector. Always follow the gauge manufacturer's instructions on set-up when installing the gauge. 6. Crank the engine and note the reading on the gauge. The vacuum should be 9-10 in. Hg. 7. Replace the fuel pump if the vacuum reading is outside the specified range. All fuel pumps covered here are of the sealed variety; no adjustments or rebuilds are possible. 8. Turn off the engine, remove the gauge and fuel line and then remove the connector. Reinstall the fuel to the fitting and tighten to 18 ft. Ibs. (24 Nm). Reconnect the ignition coil leads. FUEL TEST The fuel line, from the tank to the fuel pump, can be quickly tested by PRESSURE TEST disconnecting the existing fuel line at the fuel pump and connecting a gallon portable tank and fuel line. This simple substitution eliminates the fuel tank and fuel lines in the boat. Now, start the engine and check the performance. Always have a fire extinguisher when part of If the problem has been corrected, the fuel system between the fuel pump the fuel system. very smaliamount of the DERA inlet and the fuel tank is at fault. This area includes the fuel line, the fuel bilge, has the tremendous potential explosive power. pickup in the tank, the fuel filter, anti-siphon valve, the fuel tank vent, and excessive foreign matter in the fuel tank, and loose fuel fittings sucking air Open or remove the engine hatchicovers. Disconnect the battery into the system. Improper size fuel fittings can also restrict fuel flow, cables. Possible cause of fuel line problems may be deterioration of the inside 2. Confirm that there is fuel in the tank. Also, make sure that the fuel lining of the fuel line which may cause some of the lining to develop a filter and the carburetor inlet filter are clean and free of obstructions; we blockage similar to the action of a check valve. Therefore, if the fuel line recommend replacing the filters before performing this test. appears the least bit questionable, replace the entire line. 3. Position a container under the fuel pump and remove the outlet line Another possible restriction in the fuel line may be caused by some heavy (the line leading to the carburetor). It is important to use two open-end object lying on the line-a tackle box, etc. wrenches; one to hold the fitting elbow and the other to loosen the line nut. Plug the line with a golf tee or something similar to prevent additional fuel spillage. 4. Thread a 'tee' or a fuel pressure gauge connector into the fitting elbow on the pump and then reconnect the fuel line to the other end. 5. Connect a fuel pressure test gauge to the remaining fitting on the DESCRIPTION connector. Always follow the gauge manufacturer's instructions on set-up when installing the gauge. See Figure 94 6. Connect the battery cables, start the engine and let it idle. The fuel pressure should be 5 Ford All engines, 1993-98 GM engines and all engine where it should be 5-6 psi (34.5-41.4 except on the psi (39.6-48.3 engines utilize an electric fuel pump with their carbureted fuel 7. Slowly run the engine up to 1,800 rpm and check that the pressure systems. remains the same. The electric fuel pump system includes the fuel a water separating 8. If pressure varies, or is off specification at all, replace the pump. All fuel filter, the electric fuel pump and a carburetor. fuel pumps covered here are of the sealed variety; no adjustments or pumps covered herein utilize a 12V motor running continuously at rebuilds are possible. 4000 rpm during cranking or operation. The motor drives a conventional 9. Turn off the engine, remove the pressure gauge and fuel line and gear-type pump using incoming fuel as coolant. Fuel is supplied at varying then remove the connector. Reinstall the fuel line to the fitting and tighten to pressures determined by both engine load and fuel consumption. A fuel 18 ft. Ibs. (24 Nm). pressure regulator eliminates the need for a return line. Whenever the ignition switch is in the START position, voltage is supplied VACUUM TEST to the fuel pump relay via the 85 or S terminal on the starter relay. Once the relay is activated, voltage is applied to pump motor and then on to ground. DERATE This circuit is protected by a circuit breaker (12.5 amp on some 6 amp on others). Once the ignition switch is in the RUN If experiencing slow starts or long cranking tests, this test position, voltage is supplied via the alternator "light" terminal. after confirming that fuel pump pressure is acceptable. Electric fuel pumps are not repairable, adjustable or rebuildable. 8-32 FUEL SYSTEMS -CARBURETORS Filter 94 The electric fuel pump is usually located at the front of the engine. Mounting hardware may differ slightly on certain models 3. Cut the plastic tie holding the electrical leads to the body of the pump. Unplug the electrical harness at the pump suppressor connector and move it out of the way. 4. Hold the pump end cap (just under the lower edge of the upper Always have a fire extinguisher handy when working on any part of retaining bracket) with a wrench while loosening the lock nut (on top of the fuel system. Remember, a very small amount of fuel vapor in the bracket, under elbow). Unscrew the upper elbow. bilge, has the tremendous potential explosive power. REMOVAL INSTALLATION All OMC fuel pumps are designed to meet U.S. Coast Guard fuel system reaulations. Never substitute and automotive stvle oumo. Open or remove the engine Disconnect the battery cables. 2. Position a container under the pumplfilter assembly and remove the fuel inlet line at the filter bracket and the outlet line at the top of the pump. It is important to use two open-end wrenches; one to hold the fuel fitting nut or elbow and the other to loosen the line nut. Plug the line with a golf tee or something similar to prevent additional spillage. Take care not to spill fuel on a hot engine, because such fuel may ignite. Not holding while loosening the lock nut will damage the internal causina fuel durina operation. 5. Remove the 2 fuel filter bracket mounting bolts and lift off the as an assembly, sliding the pump out of the upper grommet. Be careful of spilling fuel. 6. Lay the assembly down, or carefully mount the bracket in a vise. Hold the lower pump end cap with a wrench and unscrew the filter to-pump adapter. FUEL SYSTEMS -CARBURETORS 8-33 Not holding the end cap while loosening the lock nut will damage the internal O-ring, causing fuel leakage during operation. To Install: Electric fuel pumps all look familiar, but will usually have different flow rates-always make sure that you have the correct pump for your engine. 7. Slide a new O-ring over the threads of the adapter until it rests on the upper side of the hex nut. 8. Screw the assembly into the pump while holding the lower end cap. Tighten the adapter to 8-10 ft. Ibs. (11-14 Nm). 9. Slide the assembly up through the grommet in the bracket and position it so the mounting holes line up on the bracket. Tighten the filter bracket bolts to 20-25 ft. Ibs. (27-34 Nm). 10. Thread the upper lock nut onto the elbow until it reaches the underside of the fitting. Slip on the washer and then a new O-ring. Thread the elbow into the top of the pump until it stops and then back it out just enough to align with the fuel line. Connect the line and tighten it securely. Hold the upper end cap again and tighten the lock nut to 60-84 inch (6.8-9.5 Nm). 12. Reconnect the suppressor lead-push it in until the tabs click. If you notice any of the suppressor holes open, be sure to coat them with Liquid Neoprene to prevent water from entering. 13. Install a new plastic tie around the pump body and electrical leads. 14. Reconnect the inlet line and tighten it securely. 15. Install the pump guard if removed. 16. Remove the container and connect the battery cables. Start the engine and check for fuel leaks. PRESSURE TEST See This test MUST be performed with the boat in the water and the engine running. It is imperative that an assistant be with you in the boat also to check the pressure readings. 95 1. Open or remove the engine hatchicovers. Disconnect the battery cables. 2. Position a container under the fuel line connection at the carburetor (or the outlet side of the fuel pump) and remove the fuel line. It is important to use two open-end wrenches; one to hold the fitting and the other to loosen the line nut. Plug the line with a golf tee or something similar to prevent additional fuel spillage. Engine Fuel Speed Pressure 4.9-8.5 Fig. 95 Electric fuel pump pressure test specifications 3. Thread a 'tee' or a fuel pressure connector into the fitting nuffelbow on the carburetor or pump and then reconnect the fuel line to the other end. 4. Connect a fuel pressure test gauge to the remaining fitting on the connector. Always follow the gauge manufacturer's instruction when setting up the pressure gauge. 5. Connect the battery cables, start the engine and let it idle. The fuel pressure should be 4.9-8.5 psi. 6. Slowly run the engine up to 4600 rpm, checking the fuel pressure readings at each of the listed engine speed readings. New engines will almost always have lower operating pressures than engines that have been broken in, 7. If pressure varies from specifications, replace the pump. 8. Turn off the engine, remove the pressure gauge and fuel line and then remove the connector. Reinstall the fuel line to the fitting and tighten to 18 Ibs. (24 Nm). FUEL SYSTEM CHECKS Check that the fuel filter is debris free and seals tightly against mounting bracket and threads. Check that the carburetor inlet filter screen is clean and free of debris. Check for kinked, bent, crushed or damaged fuel lines. Check for restricted anti-siphon valve; or incorrect valve. Check for cracked, obstructed or damaged fuel pick-up screen in fuel tank. Check for blocked or broken fuel tank vent. COMPONENT REPLACEMENT Circuit Breaker 1. Open or remove the engine Disconnect the battery cables. 2. Locate the circuit breaker on the pump bracket. Tag and disconnect the electrical leads, remove the 2 mounting screws and lift off the breaker. 3. Install a new breaker and tighten the mounting bolts to inch Ibs. Nm). 4. Attach the Red lead to one stud and the lead to the other. Tighten the nuts to 20-25 inch Ibs. (2.3-2.8 Nm). 5. Coat both terminals with Liquid Neoprene. Reconnect the battery cables. Relay And Bracket 1. Open or remove the engine Disconnect the battery cables. 2. Cut the plastic tie, remove the wire retainer and then disconnect the plug near the solenoid. 3. Tag and disconnect the two leads at the circuit breaker. 4. Tag and disconnect the Green electrical lead at the terminal on the rear of the alternator. 5. Cut the plastic tie holding the harness to the pump and then disconnect the connector at the pump suppressor. 6. Remove the two mounting screws and lift off the relay bracket. Unplug the relay. To Install: 7. Pop the relay into the mounting bracket, position the bracket and tighten the screws to 20-25 inch Ibs. Nm). 8. Align the connector tabs and press the pump suppressor connector halves together until they click. Reattach the harness to the pump body with the plastic tie. 9. Reroute the green lead through the clamps on the front of the engine and connect it to the alternator. 10. Reattach the two circuit breaker leads and coat the terminals with Liquid Neoprene. 11. Reconnect the two halves of the connector and press it into the wire retainer. Secure the connector to the retainer with a plastic tie. 8-34 FUEL SYSTEMS -CARBURETORS In order to prevent the engine from stalling during high vacuum conditions, a deceleration (gulp) valve is used on all carbureted Ford engines. Air is allowed to flow into the intake manifold, entering the mixture so as to lean out the rich condition frequently created by high vacuum when the throttle valves are closed on rapid deceleration. Sudden vacuum acts to draw down the in the valve, opening the valve and allowing air to flow through the screen and into the manifold. FUNCTION CHECK Start the engine and allow it to reach normal operating temperature at idle. 2. Remove the small vacuum signal line from the vacuum source on the manifold. 3. Reconnect the vacuum line and listen carefully for air flowing through the screen and into the manifold. Confirm also that there is a noticeable drop in engine speed (rpm) when reconnecting the vacuum line. 4. If the air flow through the screen does not persist for at least a second or, if the idle speed does not drop, check all hoses and lines connected to the valve for damage or blockage. 5. If the lines are OK, replace the valve. REMOVAL INSTALLATION Open or remove the engine Disconnect the cables. 2. Cut the plastic ties securing the vacuum lines and screen. Remove the 2 mounting screws and lift off the valve. 3. Install a new valve and tighten the screws securely. 4. Attach the two vacuum lines and the screen and secure them with plastic ties. Electric Fuel Pump Circuit Schematic1992- 93 V6 engines FUEL SYSTEMS -CARBURETORS 8-35 1-Black 2-Red 3-Red IPurple 4-Purple 5-YellowIRed 6-Green 7-Orange Electric Fuel Pump Circuit Schematic-1994-96 V6 and engines Alternator Pump 1-Black Dio 2-Red 3-Red Purple 4-Purple 5-Yellow I Red 6-Green 7-Orange El Circuit Starter Breaker Electric Fuel Pump Circuit Schematic-1997 V6 and engines Black 2-Red 8-36 FUEL SYSTEMS -CARBURETORS Alternator Electric Fuel Pump Circuit Schematic-1998 V6 and V8 engines Alternator Remote Control Electric Fuel Pump Circuit Schematic-1994-96 V8 engines FUEL SYSTEMS -CARBURETORS 8-37 Fuel Alternator Pump Diode Assist 4-Purple 5-Yellow I Red 6-Green 7-Orange Electric Fuel Pump Circuit Schematic1997 7.41 V8 engines TORQUE SPECIFICATIONS Component ft. lbs. inch Nm Accelerator Pump Cover 5 0.6 Carburetor Mounting Nuts Holley 10-14 13-1 9 Rochester Early Models 13-1 9 Later Models 12-15 16-20 Rochester Nuts 13-19 6-8 Circuit Breaker 20-25 25-34 Fuel Bowl 45 5.1 Fuel Filter Bracket 20-25 25-34 Fuel Line Elbow 48-60 5.4-6.7 Fuel Line 8 20-24 Fuel Pump Electric Adapter 8-1 0 11-14 Filter Bracket 20-25 25-34 60-84 6.8-9.5 Mechanical 20-25 25-34 (1986-90) 12-14 16-19 991-98) 20-25 25-34 20-25 25-34 (GM) 20-25 25-34 18-20 24-27 20-25 25-34 Inlet Needle seat 1.1 Power Valve 11.3 8-38 FUEL YSTEMS -CARBURETORS CARBURETOR APPLICATIONS Engine Horsepower Fuel Year Model (At Prop.) Delivery 1986 2.5 2.511 53 L4 NA Rochester IGE 2 bbl 3.0 3.01181 L4 NA Rochester 2 bbl 4.3 V6 NA Rochester IGE 2 bbl 4.3 V6 NA Rochester Quadrajet 4 bbl 5.0 5.01302 V8 185 Rochester Quadrajet 4 bbl 5.7 5.71350 V8 230 Rochester Quadrajet 4 bbl 1987 2.3 2.31140 L4 NA Rochester 2 bbl 3.0 3.01181 L4 NA Rochester IGE 2 bbl 4.3 4.31262 V6 NA Rochester 2 bbl 4.3 4.31262 V6 NA Rochester Quadrajet 4 bbl 5.0 5.01302 V8 185 Rochester Quadrajet 4 bbl 5.7 5.71350 V8 230 Rochester Quadrajet 4 bbl 7.5 460 7.51460 V8 NA 4 bbl 1988 2.3 2.311 40 L4 NA Rochester 2 bbl 3.0 3.011 81 L4 NA Rochester IGE 2 bbl 4.3 4.31262 V6 NA Rochester IGE 2 bbl 4.3 4.31262 V6 NA Rochester Quadrajet 4 bbl 5.0 185 Rochester IGE 2 bbl 5.0 5.01302 V8 200 Rochester Quadrajet 4 bbl 5.7 5.71350 V8 230 Rochester Quadrajet 4 bbl 350 5.71350 V8 NA Rochester Quadrajet 4 bbl 7.5 460 7.51460 V8 NA 4 bbl 1989 2.3 L4 NA Rochester 2 bbl 3.0 3.01181 L4 Rochester 2 bbl 4.3 4.31262 V6 160 Rochester IGE 2 bbl 5.0 5.01302 V8 1851200 2300 2 bbl 5.7 5.71350 V8 230 Rochester Quadrajet 4 bbl 5.8 5.81351 V8 235 4 bbl 262 4.31262 V6 NA Rochester Quadrajet 4 bbl 350 5.71350 V8 NA Rochester Quadrajet 4 460 7.51460 NA 4 bbl 1990 2.3 2.311 40 L4 NA 2300 (350 cfm) 2 bbl 3.0 3.011 81 L4 120 2300 (350 cfm) 2 bbl 3.0 HO 3.011 81 L4 NA 2300 (500 cfm) 2 bbl 4.3 4.31262 V6 160 2300 (500 cfm) 2 bbl 4.3 HO 4.31262 V6 NA 41 60 (575 4 bbl 5.0 5.01302 V8 185 2300 (300 cfm) 2 bbl 5.0 HO 5.01302 V8 200 2300 (300 cfm) 2 bbl 4175 (650) 4 bbl 5.7 5.71350 V8 230 5.7 LE 5.71350 V8 NA 4175 (650) 4 bbl 5.8 V8 235 41 60 (600 cfm) 4 bbl 350 5.71350 V8 NA 41 75 (650) 4 bbl 454 7.41454 V8 NA 4150 (850 4 460 7.51460 V8 NA 4160 (750 cfm) 4 bbl Electric choke PWC models used a Rochester 2 bbl carburetor Spread bore Dual feed FUEL SYSTEMS -CARBURETORS 8-39 CARBURETOR APPLICATIONS Displacement Engine Horsepower Carburetor Fuel Year Model In. (At Prop.) Delivery 1991 3.0 81 L4 120 2300 (350 dm) 2 bbl 3.0 HO 3.01181 L4 NA 2300 (500 2 bbl 4.3 4.31262 V6 1 60 2300 (500 dm) 2 bbl 4.3 HO V6 NA 41 60 (575 cfrn) 4 bbl 5.0 5.01302 V8 1 85 2300 (300 cfm) 2 bbl 5.0 HO 5.01302 V8 200 Holley 2300 (490 2 bbl 5.7 5.71350 V8 230 4175 (650) 0 4 bbl 5.7 LE, 350 5.71350 V8 NA 41 75 (650) 4 bbl 5 8 V8 235 4160 (600 cfm) 4 bbl 454 7.41454 V8 300 41 50 (750 cfrn) 4 bbl 454 HO V8 390 4150 (850 cfm) 4 1992 3.0 3.01181 L4 I20 Holley 2300 (350 cfm) 2 bbl 3.0 HO 81 L4 NA 2300 (500 cfm) 2 bbl 4.3 4.31262 V6 1 60 2300 (500 cfm) 2 bbl 5.0 5.01302 V8 185 2300 (300 cfm) 2 bbl 5.0 HO 5.01302 V8 200 2300 (490 2 bbl 5.7 5.71350 V8 230 41 75 (650) 0 4 bbl 5.7 LE 5.71350 V8 NA 4175 4 bbl 58 V8 235 Holley 41 60 (600 cfm) 4 bbl 5.8 LE, 351 5.81351 V8 235 4160 (600 cfm) 4 bbl 454 V8 300 4150 (750 cfm) 4 bbl 502, 454 HO V8 390 4150 (850 cfm) 3.0 3.01181 L4 1 20 2300 (350 cfm) 2 bbl 3.0 HO 3.011 81 L4 130 2300 (500 cfm) 2 bbl 4.3 V6 1 60 2300 (500 cfm) 2 bbl 4.3 HO 4.31262 V6 NA 41 60 (575 cfm) 4 bbl 5.0 5.01302 185 2300 (300 cfm) 2 bbl 5.0 HO 5.01302 V8 200 2300 (490 cfm) 2 bbl 5.8 V8 235 41 60 (600 cfrn) 4 bbl 7 41454. . . . . . 41 50 1750 4 hhl. 1994 3.011 81 L4 1 20 2300 (350 cfrn) 2 bbl 3.01181 L4 135 2300 (500 cfrn) 2 bbl 4.31262 V6 1 60 2300 (500 cfrn) 2 bbl 5.01302 V8 190 2300 (490 cfm) 2 bbl 5.71350 V8 225 2300 (500 cfm) 2 bbl 5.81351 V8 230 4160 (600 cfm) 4 bbl V8 300 41 50 (750 cfrn) 4 1995 3.01181 L4 130 2300 (500 cfm) 2 bbl V6 160 2300 (500 cfrn) 2 5.01302 V8 190 2300 (490 cfm) 2 bbl 5.81351 V8 235 4160 (600 . 4 bbl 7.41454 V8 300 41 50 (750 cfm) 4 1996 3.01181 L4 30 Holley 2300 (500 cfm) 2 bbl 4.31262 V6 160 2300 (500 cfm) 2 bbl V6 1 85 41 60 (575 cfm) 4 bbl 5.01302 V8 190 2300 (490 cfrn) 2 bbl V8 235 4160 dm) 4 bbl 7.41454 V8 300 4150 (750 cfrn) 4 Spread bore Single feed Dual feed 8-40 FUEL SYSTEMS -CARBURETORS CARBURETOR APPLICATIONS Displacement Year Model In. 1997 3.011 81 Engine L4 Horsepower (At Prop.) 135 Carburetor Fuel Delivery 2 bbl 4.31262 V6 2300 (500 cfm) 2300 (500 cfrn) 2 bbl 4.31262 V6 205 4160 (575 cfrn) 4 bbl 21 5 2300 (500 cfm) 2 bbl 5.71350 250 41 75 (650 cfrn) 4 bbl 7.41454 300 41 50 (750 cfm) 4 bbl 1998 2300 (500 cfm) 2 bbl 3.01181 L4 135 2300 (500 cfm) 2 bbl 4.31262 V6 190 41 60 (575 cfm) 4 bbl 4.31262 V6 205 220 2300 (500 dm) 2 bbl 5.01305 250 2300 (500 cfm) 2 bbl 5.71350 Spread bore Single feed Model 300 1 989 1990 1991 350 1989-90 1991 1992-94 490 5.0 HO, 500 3.0 HO, 1990 1990-91 1995-98 1991 1992-98 CARBURETOR SPECIFICATIONS HOLLEY 2300 Choke Choke Choke Unloader Vacuum Float Mixture Main Setting (mm) in. Setting (Turns) Jet Inotch lean 0.270-0.330 0.130-0.150 1 off seat 60 (6.8-8.4) (3.3-3.9) 1 notch lean 0.300 (7.6) 0.140 (3.6) Level 1 off seat 60 3 notches lean 0.300 (7.6) 0.228 (5.8) 1 off seat 61 3 notches lean 0.300 (7.6) 0.228 (5.8) 1 off seat 61 3 notches lean 0.380 (9.625) 0.250 (6.35) Level 314 off seat 63 3 notches lean 0.380 (9.625) 0.250 (6.35) 314 off seat 63 3 notches lean 0.380 (9.625) 0.250 (6.35) 314 off seat 63 3 notches lean 0.312 (7.93) 0.221 (5.6) off seat 72 5 notches lean 0.300 (7.62) 0.365 (9.3) Level 75 5 notches lean 0.300 (7.62) 0.365 (9.3) 75 5 notches lean 0.300 (7.62) 0.365 (9.3) 75 5 notches lean 0.300 (7.62) 0.365 (9.3) 71 5 notches lean 318 (9.525) 0.250 (6.35) Level 518 off seat 70 5 notches lean 318 (9.525) 0.250 (6.35) 518 off seat 70 5 notches lean 318 (9.525) 0.250 (6.35) off seat 70 5 notches lean 0.300 (7.62) 0.315 (8) 3141 off seat 75 5 notches lean 0.300 (7.62) 0.315 (8) off seat 69 Accelerator Pump Pump Power Lever Cam Valve in. (mm) Position 50 Hole (0.1 30-0.381) 50 0.010-0.015 Hole (0.254-0.381) 3.5 Hole ) 3.5 0.010-0.015 Pink Hole 25 Hole (0.254-0.381) 2.5 0.010-0.015 Hole ) 2.5 0.010-0.015 Orange (0.254-0.381) 3.5 Orange (0.254-0.381) Hole 25 0.01 0-0.01 5 Hole ) 2.5 0.010-0.015 Hole ) 2.5 0.010-0.015 Orange Hole 2.5 0.010-0.01 5 Orange Hole 25 Hole ) 2.5 0.010-0.015 Hole ) 2.5 0.010-0.015 Red (0.254-0.381) # 1 Hole 4.5 0.010-0.015 Red # 1 Hole 4.5 0.010-0.015 Yellow 1 Hole Measured at lower edge of plate Parallel to fuel bowl when bowl inverted Level with fuel bowl inverted; Secondary: turns in 1 turn starboard to 112 turn port off seat 1998: Throttle lever side -67; choke coil side -68 FUEL SYSTEMS -CARBURETORS 8-41 CARBURETOR SPECIFICATIONS -HOLLEY 4BBL Accelerator Accelerator Secondary Choke Choke Unloader Choke Vacuum Float Mixture Power Pump Lever Pump Cam Throttle Plate Model Engine Year Setting In. in. Settlng (Turns) Jet Valve (Turns) 1989 1 notch lean 0.130-0.150 1 112 Turns Out 73 65 (0.127-0.381) Hole Beyond Contact 750 1 notch rich 0.270-0.330 1 112 Turns 73 65 0.005-0.015 Hole 114 Beyond Out Contact 1989 1 notch lean 0.270-0.330 1 112 Turns 73 65 0.0050.015 Hole 114 Beyond (3.3-3.9) Out (0.1 Contact 4150 750 1990 5 notches lean Turn Out 88 6.5 (Pri.) Hole 118 Beyond (6.3-12.7) 3.5 Contact notches lean 0.344 0.312 (7.92) 114 off seat 73 2.5 0.010-0.015 Orange 118 Beyond 56 2.5 Hole Contact 850 5 114-112 Turn Out 88 (Pri.) 6.5 0.010-0.015 Orange 118 Beyond (10.5-10.8) 84 3.5 Hole Contact 4160 575 4.3 HO 1990 5 notches lean 0.300 (7.62) 0.250 (6.35) 314 Turn Out 67 25 0.010-0.015 Hole Beyond Contact 1991 5 notches lean 0.300 (7.62) 0.250 (6.35) 314 Turn Out 67 2.5 Hole 114 Beyond Contact 1993 5 notches lean 0.300 (7.62) 0.250 (6.35) 314 Turn Out 67 2.5 0.010-0.015 Orange Hole Contact 5 notches lean 0.300 (7.62) 0.250 (6.35) 314 off seat 67 2.5 0.010-0.015 Orange Beyond (0.254-0.381) Hole Contact 1998 5 notches lean (7.62) 0.250 (6.35) 1 118 off seat 63 2.5 Green Beyond hole Contact 600 1990 1 notch lean 0.300 (7.62) 0.140 (3.6) 1 73 65 0.010-0.015 Hole 114 Beyond Out ) Contact 1991-96 3 notches lean 0.300 (7.62) 0.228 (5.8) 718 off seat 67 2.5 Orange 118 Beyond Hole Contact Hole 114 Beyond Out (0.254-0.381) Contact 351 1992 3 notches lean 0.300 (7.62) 0.228 (5.8) 314 off seat 69 4.5 0.010-0.015 Orange 118 Beyond (0.254-0.381) Hole Contact 750 1990 1 notch lean 0.300 (7.62) 0.140 (3.6) 1 73 6.5 0.010-0.015 Measured at lower edge of plate Both parallel to fuel bowl when bowl is inverted CARBURETOR SPECIFICATIONS -HOLLEY 4BBL lntital Accelerator Accelerator Secondary Choke Choke Pump Pump Choke Unloader Vacuum Float Mixture Power Lever Cam Plate Model Engine Year Sefflng in. Setting (Turns) Jet Valve in. (mm) Posltion (Turns) 4175 650 1990 0.230-0.240 0.228 (5.8) Level 114 off seat 60 50 Hole 118 Beyond (0.254-0.381) Contact 1991 Index 0.230-0.240 0.228 (5.8) 114 off seat 60 5.0 Hole 118 Beyond Contact 1992 Index 0.230-0.240 0.228 (5.8) offseat 60 2.5 Orange 118 Beyond (5.9-6.1) (0.254-0.381) Hole Contact 1997 Index 0.230-0.240 0.228 (5.8) 112 off seat 60 2.5 0.010-0.015 Orange 118 Beyond (5.9-6.1) Hole Contact 5.7 LE, 1990 Index 0.228 (5.8) Level 1 off seat 60 5.0 0.010-0.015 Hole 118 Beyond 350 (5.9-6.1) (0.254-0.381) Contact 1991 0.230-0.240 0.228 (5.8) 1 off seat 60 5.0 0.010-0.015 Hole 118 Beyond Contact 1 992 Index 0.228 (5.8) seat 60 2.5 0.010-0.015 Orange Beyond (5.9-6.1) Hole Contact Measured at lower edge of plate Both parallel to fuel bowl when is inverted For Part Part 112 turn off seat For Part Part 2.5 Part is 112 turn off seat Part and 80391 should be 2.5 8-42 FUEL SYSTEMS -CARBURETORS CARBURETOR ROCHESTER Accelerator Initial Float Float Pump Vacuum Choke Initial Level Rod Break Unloader Choke Mixture CARBURETOR SPECIFICATIONS ROCHESTER Pump initial Float Rod Pump Vacuum Choke Level Adjustment Rod Break Unloader Mixture Year Model Engine in. (mm) in. Position in. (mm) in. (mm) (Turns) 1986 1708251 5 5/16 (7.77) 23/64 (9.14) Hole (3.18) 15/64 (5.94) 3 17058286 5/16 (7.77) 23/64 (9.14) lnner Hole (3.18) 15/64 (5.94) 3 1987 1708251 5 5/16 (7.77) 23/64 (9.14) Inner Hole (3.18) 15/64 (5.94) 3 17059286 5/16 (7.77) 23/64 (9.14) lnner Hole (3.18) 15/64 (5.94) 3 1988 5 5/16 (7.77) 23/64 (9.14) Hole (3.18) 15/64 (5.94) 3 17059286 5/16 (7.77) 23/64 (9.14) lnner Hole (3.18) 15/64 (5.94) 3 1989 17082515 262 5/16 (7.77) 23/64 (9.14) Inner Hole (3.18) 15/64 (5.94) 3 17059286 350 5/16 (7.77) 23/64 (9.14) lnner Hole (3.18) 15/64 (5.94) 3 COMPONENT LOCATIONS ............. 9-73 DIAGNOSTIC TROUBLE CODES (DTC READING CODES FORD 9-19 GM 9-48 CLEARING CODES FORD 9-20 GM 9-48 DIAGNOSTIC TROUBLE CODE (DTC) CHARTS 9-70 ECM PIN LOCATIONS FORD 9-21 GM 9-60 ELECTRONIC CONTROL ASSEMBLY .. FORD ELECTRONIC CONTROL MODULE (ECM) GM 9-26 ENGINE COOLANT TEMPERATURE SENSOR (ECT) FORD 9-8 GM 9-26 FORD ELECTRONIC MULTI-POINT FUEL INJECTION (MFI) AIR CHARGE TEMPERATURE SENSOR (ACT) 9-8 CIRCUIT BREAKER 9-8 CLEARING CODES 9-20 DESCRIPTION OPERATION DIAGNOSTIC TROUBLE CODES 9-18 EEC POWER RELAY ELECTRONIC CONTROL ASSEMBLY (ECA) 9-9 ENGINE COOLANT TEMPERATURE SENSOR (ECT) 9-8 FUEL INJECTOR 9-10 FUEL PRESSURE REGULATOR 9-10 FUEL PUMP 9-10 FUEL RAIL 9-11 FUEL SEPARATOR 2 IDLE SPEED CONTROL (ISC) SOLENOID KNOCK SENSOR (KS) AND AMPLIFIER 9-12 MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR 9-13 PIN LOCATIONS 9-21 READING CODES 9-19 RELIEVING FUEL PRESSURE 9-8 SYSTEM DIAGNOSIS 9-14 THROTTLE BODY 9-14 THROTTLE POSITION SENSOR (TP) 9-14 VACUUM DIAGRAMS 9-21 FUEL AND COMBUSTION FUEL 9-2 COMBUSTION 9-2 FUEL FLOW DIAGRAMS 9-71 FUEL INJECTOR FORD 9-10 GM 9-27 GM MFI 9-27 FUEL PRESSURE REGULATOR FORD 9-10 GM 9-29 FUEL PUMP FORD 9-10 GM 9-30 GM THROTTLE BODY FUEL INJECTION (TBI) .............................. 9-22 GM MULTI-POINT FUEL INJECTION (MFI) . 9-22 CIRCUIT BREAKER ................. 9-26 CLEARING CODES ..................9-48 COOLANT COVER ASSEMBLY ......... 9-26 DESCRIPTION OPERATION ......... 9-22 DIAGNOSTIC TEST SCHEMATICS ...... 9-44 DIAGNOSTIC TROUBLE CODES ....... 9-48 DIAGNOSTIC TROUBLE CODE SCHEMATICS ......................9-51 ELECTRONIC CONTROL MODULE ............................9-26 ENGINE COOLANT TEMPERATURE SENSOR (ECT) ..................... 9-26 FUEL INJECTORS ................... 9-27 FUEL METER BODY ................. 9-28 FUEL METER COVER ................ 9-29 FUEL PRESSURE REGULATOR ........ 9-29 FUEL PUMP .......................9-30 FUEL PUMP RELAY ................. 9-32 FUEL ........................9-32 GENERAL DIAGNOSTIC TESTS ........ 9-40 IDLE AIR CONTROL VALVE (IAC) ....... 9-33 INTAKE AIR TEMPERATURE SENSOR (IAT) ... 9-35 KNOCK SENSOR (KS) ............... 9-35 KNOCK SENSOR MODULE ........... 9-35 MANIFOLD ABSOLUTE PRESSURE SENSOR (MAP) .....................9-35 READING CODES ................... 9-48 RELIEVING FUEL PRESSURE ......... 9-26 SYSTEM DIAGNOSIS 9-40 THROTTLE BODY ................... 9-35 THROTTLE BODY ADAPTER PLATE .... 9-37 THROTTLE POSITION SENSOR (TP) .... 9-39 VAPOR SEPARATOR . . RESERVOIR ....................... 9-39 KNOCK SENSOR (KS) ................ FORD ............................9-12 GM 9-35 MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR FORD 9-13 GM 9-35 RELIEVING FUEL PRESSURE FORD ............................ 9-8 GM ..............................9-26 SPECIFICATIONS VOLTAGE REFERENCE VALUES (FORD) . 9-20 SYSTEM DIAGNOSIS FORD 9-14 GM ..............................9-40 THROTTLE BODY FORD 9-14 GM-TBI 9-35 GM.MFI 9-37 THROTTLE POSITION SENSOR (TP) FORD ............................9-14 GM 9-39 SCHEMATICS DIAGNOSTIC TESTS (GM) 9-44 DTC 9-51 SYSTEM (FORD) .................... 9-53 SYSTEM (GM) 9-56 TORQUE 9-77 9-2 FUEL SYSTEMS -FUEL INJECTION FUEL SYSTEM APPLICATIONS Displacement Engine Fuel Year Model In. Type Delivery 1993 5.01302 V8 MFI -FORD V8 MFI -FORD 1994 FORD 351 V8 MFI-FORD 1995 5.0 EFI V8 MFI -FORD 5.8 EFI V8 MFI-FORD 7.4 EFI V8 MFIGM 1996 TBI 5.01302 V8 MFI-FORD V8 TBI V8 MFI FORD V8 MFI-GM 1997 V6 TBI V8 TBI V8 MFI GM 1998 V6 TBI TBI 7.41454 MFI -GM V8 MFI-GM -- Fuel recommendations have become more complex as the chemistry of modern gasoline changes. The major driving force behind the changes in gasoline chemistry is the search for additives to replace lead as an octane booster and lubricant. These new additives are governed by the types of emissions they produce in the combustion process. Also, the replacement additives do not always provide the same level of combustion stability, making a fuel's octane rating less meaningful. In the 1960's and leaded fuel was common. The lead served two functions. First, it served as an octane booster (combustion stabilizer) and second, in 4-stroke engines, it served as a valve seat lubricant. For engines, the primary benefit of lead was to serve as a combustion stabilizer. Lead served very well for this purpose, even in high heat applications. Today, all lead has been removed from the refining process. This means that the benefit of lead as an octane booster has been eliminated. Several substitute octane boosters have been introduced in the place of lead. While many are adequate in an engine, most do not perform nearly as well as lead did, even though the octane rating of the fuel is the same. OCTANE RATING A fuel's octane rating is a measurement of how stable the fuel is when heat is introduced. Octane rating is a major consideration when deciding whether a fuel is suitable for a particular application. For example, in an engine, we want the fuel to ignite when the spark plug fires and not before, even under high pressure and temperatures. Once the fuel is ignited, it must burn slowly and smoothly, even though heat and pressure are building up while the burn occurs. The unburned fuel should be ignited by the traveling flame front, not by some other source of ignition, such as carbon deposits or the heat from the expanding gasses. A fuel's octane rating is known as a measurement of the fuel's anti-knock properties (ability to burn without exploding). Usually a fuel with a higher octane rating can be subjected to a more severe combustion environment before spontaneous or abnormal combustion occurs. To understand how two gasoline samples can be different, even though they have the same octane rating, we need to know how octane rating is determined. The American Society of Testing and Materials (ASTM) has developed a universal method of determining the octane rating of a fuel sample. The octane rating you see on the pump at a fuel dock is known as the pump octane number. Look at the small print on the pump. The rating has a formula. The rating is determined by the method. This number is the average of the research octane reading and the motor octane rating. The Research Octane Rating is a measure of a fuel's anti-knock properties under a light load or part throttle conditions. During this test, combustion heat is easily dissipated. The Motor Octane Rating is a measure of a fuel's anti-knock properties under a heavy load or full throttle conditions, when heat buildup is at maximum. VAPOR PRESSURE Fuel vapor pressure is a measure of how easily a fuel sample evaporates. Many additives used in gasoline contain aromatics. Aromatics are light hydrocarbons distilled off the top of a crude oil sample. They are effective at increasing the research octane of a fuel sample but can cause vapor lock (bubbles in the fuel line) on a very hot day. If you have an inconsistent running engine and you suspect vapor lock, use a piece of clear fuel line to look for bubbles, indicating that the fuel is vaporizing. One negative side effect of aromatics is that they create additional combustion products such as carbon and varnish. If your engine requires high-octane fuel to prevent detonation, de-carbon the engine more frequently with an internal engine cleaner to prevent ring sticking due to excessive varnish buildup. ALCOHOL-BLENDED FUELS When the Environmental Protection Agency mandated a phase-out of the leaded fuels in January of 1986, fuel suppliers needed an additive to improve the octane rating of their fuels. there are multiple methods currently employed, the addition of alcohol to gasoline seems to be favored because of its favorable results and low cost. Two types of alcohol are used in fuel today as octane boosters, methanol (wood alcohol) or ethanol (grain alcohol). When used as a fuel additive, alcohol tends to raise the research octane of the fuel. There are, however, some special considerations due to the effects of alcohol in fuel. Since alcohol contains oxygen, it replaces gasoline without oxygen content and tends to cause the mixture to become leaner. On older engines, the leaching affect of alcohol may, in time, cause fuel lines and plastic components to become brittle to the point of cracking. Unless replaced, these cracked lines could leak fuel, increasing the potential for hazardous situations. water, rhe tank. leaves the gasoline on a top layer. Modern fuel lines and plastic fuel system components have been specially formulated to resist alcohol leaching effects. RECOMMENDATIONS All engine covered here are designed to run on unleaded fuel. Never use leaded fuel in your boat's engine. The minimum octane rating of fuel being used for your engine must be at least 87 AKI (outside the US: 90 RON), which means regular unleaded, but some engines may require higher octane ratings. OMC actually recommends the use of 89 AKI (93 RON) fuel as the ideal-in fact, anything less than this on many engines will require a change to the ignition timing. Fuel should be selected for the brand and octane that performs best with your engine. Check your owner's manual if in doubt. Premium unleaded is more stable under severe conditions but also produces more combustion products. Therefore, when using premium unleaded, more frequent de-carboning is necessary. The use of a fuel too low in octane (a measure of anti-knock quality) will result in spark knock. Newer systems have the capability to adjust the engine's ignition timing to compensate to some extent, but if persistent knocking occurs, it may be necessary to switch to a higher grade of fuel. Continuous or heavy knocking may result in engine damage. In a high heat environment like an modern engine, the fuel must be very stable to avoid detonation. If any parameters affecting combustion change (the enqine runs lean for example), uncontrolled heat buildup will occurs The combustion is affected several interrelated factors. This means that when factor is other factors also must be changed to maintain the same controlled burn and level of combustion stability. FUEL SYSTEMS -FUEL INJECTION 9-3 the level of heat buildup in the cylinder when the air-fuel mixture is compressed. As compression increases, so does the potential for heat buildup Ignition when the gasses will start to expand in relation to the motion of the If the ignition timing is too advanced, gasses will be ignited and begin to expand too soon, such as they would during pre-ignition. The motion of the piston opposes the expansion of the gasses, resulting in extremely high combustion chamber pressures and heat. If the ignition timing retarded, the gases are ignited later in relation to piston position. This means that the piston has already traveled back down the bore toward the bottom of the cylinder, resulting in less usable power. Fuel Mixture--determines how efficient the burn will be. A rich mixture burns slower than a lean one. If the mixture is too lean, it can't become explosive. The slower the burn, the cooler the combustion chamber, because pressure buildup is gradual. Fuel Quality (Octane Rating)-determines how much heat is necessary to ignite the mixture. Once the burn is in progress, heat is on the rise. The unburned poor quality fuel is ignited all at once by the rising heat instead of burning gradually as a flame front of the burn passing by. This action results in detonation (pinging). There are two types of abnormal combustion-pre-ignition and detonation. Pre-ignition--occurs when the air-fuel mixture is ignited by some incandescent source other than the correctly timed spark from the spark Detonation-occurs when excessive heat and or pressure ignites the mixture rather than the spark plug. The burn becomes explosive. In general, anything that can cause abnormal heat buildup can be enough to push an engine over the edge to abnormal combustion, if any of the four basic factors previously discussed are already near the danger point, for example, excessive carbon buildup raises the compression and retains heat as glowing embers. See Figures 1, 2, 3,4 and 5 The purpose of this section is to describe-in layman's terms whenever possible-the Multi-Port Fuel Injection (MFI) system installed on many Ford engines covered here. Visual inspections, and simple tests that may be performed using only as possible, complete combustion. On MFI systems, there is a throttle body located on the intake manifold, much like a carburetor except that only air is distributed and metered through the bores on the throttle body' Air for combustion is controlled by a throttle valve connected to the throttle linkage. Fuel is supplied by individual injectors mounted in the intake manifold and attached to a fuel rail assembly. Each injector is "pulsed" or "timed" to open or close by an electronic signal from the ECM. While constantly receiving input from various sensors, the ECM performs high speed calculations of engine fuel requirements and then "pulses the injectors open or closed. Ford's multi-point furl injection system is a pulse density fuel injection system. This is to say that fuel is metered into the intake air stream based on the engine's demand via 8 fuel injectors mounted on a tuned intake manifold. Inputs from various engine sensors are fed into an on-board electronic engine control computer (EEC-IV) which computes the necessary fuel flow rates to maintain the prescribed ratio at all times the engine is operating. The computer then sends an output signal to the injectors so they meter the correct quantity of fuel. The EEC-IV system is also capable of determining, and compensating for, engine age, uniqueness and altitude changes. The fuel delivery system consists of two fuel pumps-a low pressure pump mounted on the engine, between the fuel tank and vapor separator; and a high pressure pump mounted in the separator reservoir, delivering fuel to the injectors. Also included are a vapor separator reservoir, a fuel filter and a fuel charging system, The fuel charging system incorporates the electronic fuel injectors directly over each of the eight intake ports. When energized, the injectors spray a metered quantity of fuel directly into the intake air stream. A pressure regulator located downstream from the injectors maintains constant pressure across the injector nozzles. Excess fuel supplied by the pump, but not needed by the engine, passes through the regulator and back to the separator reservoir. On alternate revolutions of the crankshaft, one group of 4 injectors is energized simultaneously; with the remaining groups of four being energized on the next revolution. Injector "on time", or pulse width more accurately, is controlled by the EEC computer. basic shop test equipment, will be given wherever possible. Again, we emphasize: specialized test equipment, hours of training and considerable experience is required to perform detailed service on a fuel injection system.. The first fuel injection system was introduced in Europe over 60 years ago-in 1932 on diesel truck engines. In the beginning, the system and individual components were quite expensive. Over the years, state-of-the-art microprocessors (commonly referred to chips"), have lowered the cost of electronically controlled fuel injection systems. Today, the price of EFI is getting close to the cost of modern carbureted systems. An electronic fuel injection system is quite different from a carburetor system-even though they appear similar. The fuel injection system has a more efficient delivery of fuel to the cylinders than can be obtained with standard carburetor operation. The EFI system provides a means of fuel distribution by precisely controlling the airlfuel mixture and under all operating conditions for, as near Fig. 1 MFI system diagram FUEL CIRCUIT Fuel from the fuel tank is delivered, through the fuel filter, to the vapor separator reservoir via the low pressure fuel pump. Once the ignition key is switched to the ON position, the pump will energize for approximately 2 seconds and then shut off until the electronic control assembly (ECA) receives a signal from the profile ignition pick-up (PIP) indicating that the engine is cranking or running. The vapor separator reservoir is a fuel purge reservoir located at the rear of the engine, eliminating the need for fuel return lines. Fuel enters the reservoir from the bottom, passes through the high pressure pump on top of the assembly and then on to the fuel rail and injectors. When fuel demand is less than the volume of fuel being supplied, line pressure will open an internal regulator in the low pressure pump allowing the fuel to circulate internally. Power for the delivery system and appropriate timing for the injectors is controlled by the ECA. A operated diaphragm-type pressure regulator is located on the end of the fuel rail, downstream of the iniectors. One side of the regulator senses fuel pressure while the other detects manifold vacuum; thus allowing the regulator to maintain the appropriate, and equal, fuel pressure at each injector. Because of fuel vapors, the reservoir, and the fuel itself, are cooled by incoming seawater. Water enters passages in the reservoir from the transom shield water line and then continues on to the thermostat housing. 9-4 FUEL SYSTEMS -FUEL INJECTION Inside the reservoir there is a float and needle mechanism, very similar to what you're familiar with on a carburetor, which is connected to a vacuum line from the air plenum. Any vapor will separate from the liquid fuel and rise to the top of the reservoir. As the amount of vapor increases, the fuel volume will decrease, causing the float to open the needle valve. Vacuum will then pull the vapor from the reservoir and into the intake plenum. A pulse limiter at the plenum prevents backfire from igniting these vapors. Once the vapor has been purged, the low pressure pump will feed more fuel into the reservoir, causing the level to rise and the float to close the needle valve. Both the reservoir and the fuel rails are equipped with pressure relief valves. ELECTRICAL CIRCUIT As the ignition key is moved to the ON position, the EEC power relay is energized-providing power (current) to both the ECA and the fuel pump relay. Power for the pumps is supplied via 20 amp circuit breaker connected to the main 60 amp breakers on the engine. As mentioned previously, if the switch is not moved past the ON position and into the START position, the ECA will shut off the pump after approximately 2 seconds. Once moved to the START and cranking commences, the ECA will receive a signal from the PIP and once again energize the pump. The pump will continue to run until the engine speed drops below 120 rpm. COMPONENTS Fuel See Figure 6 There are 8 electro-mechanical injectors attached to the fuel rail. They are charged with metering and atomizing fuel as delivered to the engine. Each injector body consists of a solenoid-actuated pintle and needle valve assembly. A signal from the ECA activates the injector solenoid, causing the pintle to move inward and off the seat; thus allowing fuel to flow to the intake port. Fuel flow to the engine is regulated by the duration of solenoid energization, while atomization is obtained by contouring the pintle at the point where the fuel separates. OMC utilizes a Deposit Resistant Injector (DRI) so that lean fuel delivery problems caused by bad fuel (low grade) have been eliminated. These injectors have no pintle on the tip of the injector (as most injectors do); instead, fuel is metered via four small holes in a metering plate on the injector tip. As the inevitable fuel deposits coat the tip of the injector, the holes will not be affected; so metering characteristics remain correct. High Fuel Pressure Vapor Separator Fuel Pump Fig. 2 MFI system component locations-1993-94 FUEL SYSTEMS -FUEL INJECTION Fuel Pumps As discussed previously, there are two electric fuel pumps utilized with this system. A low pressure pump attached to the fuel filter bracket and a high pressure pump mounted on top of the vapor separator reservoir. Fuel Pressure Regulator The fuel pressure regulator is mounted on the rear of the Starboard rail, downstream of the injectors. The regulator is a simple diaphragm-type relief valve. One side of the diaphragm senses fuel pressure while the other side takes vacuum from the intake manifold. Nominal fuel pressure is established via the spring preload being applied to the diaphragm. Manifold pressure balance the other side of the diaphragm in order to maintain a constant pressure drop across all of the injectors. Excess fuel not needed by the engine bypasses the regulator and is returned to the separator reservoir. Fuel Rail The fuel rail delivers high pressure fuel from the vapor separator reservoir to each of the 8 injectors. The actual assembly consists of two hollow fails (one for each bank of cylinders) connected by a crossover. All fuel injectors and the pressure regulator are connected to the rail. All fuel rails are serviced as an assembly only, only the injectors and the regulator may be individually serviced. Intake Manifold The manifold assembly is actually made up of two separate manifolds; and upper and a lower. Runner lengths on the upper plenum are pre-tuned to optimize engine torque and power output. Fuel injector pockets are machined into the lower manifold in order to prevent any air or fuel leakage. These pockets are also positioned so that they the injector fuel pattern sprays directly in front of each intake valve. Throttle Body The throttle body is mounted to the upper intake manifold, Port side and controls airflow to the engine by means of a butterfly-style valve. All throttle bodies are one-piece aluminum with a bore. There is an air channel around'the throttle plate all engine idle airflow, regulated bv an electro-mechanical device controlled bv the ECA. A linear actuator ......... is. into the throttle body which a variable area metering valve known as the Speed Control (ISC) valve. Vapor Separator Tank The reservoir is located at the rear of the engine and consists of the assembly itself, the high pressure fuel pump, float assembly and various fuel and cooling lines. Operational details are discussed in the Description and Operation section. E-Core ECA. Trim and 3 MFI system component locations-1995-96 9-6 FUEL SYSTEMS -FUEL INJECTION Fuel Line Fig. 4 Exploded view of the lower manifold and fuel delivery system Lower Intake Low Pressure Circuit Breaker Reservoir FUEL SYSTEMS -FUEL INJECTION 9-7 Mounting I Bracket Sink 5 Exploded view of the upper manifold and fuel deliverv svstem 9-8 FUEL SYSTEMS -FUEL INJECTION ORIFICE Fig. 6 Cross section of an MFI injector Water Separating Fuel Filter The water separator is a "typical" unit designed to prevent moisture from continuing on through the fuel lines and eventually through the injectors into the cylinders. It can be found on the front of the engine. To reduce the risk of fire and personal injury, it is necessary to relieve the fuel system pressure before servicing any fuel system component. If this procedure is not performed, fuel may be sprayed out of a connection under extreme pressure. Always keep a dry chemical fire extinguisher near the work area when serving the fuel system. Tag and disconnect the electrical leads at each of the electric fuel pumps and move the harness out of the way. 2. Turn the ignition key and crank the engine for ten seconds to relieve any residual pressure in the system. If the engine starts, don't worry, allow it to run until it dies out and then crank the engine again for a few more seconds. 3. Reconnect the fuel pump leads. 4. Disconnect the battery cables before commencing any additional procedures. The air charge temperature sensor (or air bypass valve) monitors incoming air temperature changes and relays this information directly to the ECA. The ECA will then advance spark timing so the idle speed will increase at lower engine temperatures. Since cold air contains more oxygen, the ECA will the mixture when outside air is colder. REMOVAL INSTALLATION See Figures 2 and 3 Open the engine compartment and disconnect the battery cables. 2. Remove the 4 retaining screws and lift off the plastic engine cover. 3. Tag and disconnect the coil high tension lead, the E-coil connector and the connector at the TFI module, just forward of the throttle body. Move them all out of the way. 4. Tag and disconnect the electrical lead at the ACT sensor, just in front of the TFI module. Unscrew the sensor. To Install: 5. Install the sensor and tighten it to ft. Ibs. (16.3-24.4 Nm). Coat the electrical lead with Terminal Grease and reconnect it. 6. Apply Terminal Grease to the lead and two connectors from the module and reconnect them. Confirm that each connection is secure. 7. Install the plastic cover and tighten the screws to 24-36 inch Ibs. 4.1 Nm). 8. Connect the battery cables. TESTING See Figures 7 and 8 1. With the ignition switch in the OFF position, disconnect the electrical lead at the ACT sensor. 2. Measure the resistance across the two terminals in the sensor connector. 3. Match your reading to that in the chart for the given temperature. If within specification, the sensor is OK, otherwise replace the sensor. -- REMOVAL INSTALLATION See Figures 2,3 and 4 1. Open the engine compartment and disconnect the battery cables. 2. Locate the circuit breaker on the fuel pump lift bracket (front of engine, Port side) and disconnect the two electrical leads. 3. Remove the screwsinuts and lift off the breaker. 4. Install a new circuit breaker and tighten the to 20-25 inch Ibs. (2.3-2.8 Nm). 5. Connect the Red lead to one stud on the circuit breaker and the lead to the other. Tighten the nuts 20-25 inch Ibs. (2.3-2.8 Nm). Coat the two terminals with Liquid Neoprene. This sensor is a thermistor immersed in the engine coolant passageway. A thermistor is a resistor capable of changing value based on temperature. Low coolant temperature produces a high resistance and a high temperature causes low resistance. SENSOR DATA Temperature Voltage Resistance ( F ) ( ) (Volts) (K Ohms) 248 120 0.28 1.18 Voltage values calculated for VREF Due to sensor and VREF variactions, these values may vary by 15% Fig. 7 Sensor testing values FUEL SYSTEMS -FUEL INJECTION REMOVAL INSTALLATION + See Figures and Open the engine compartment and disconnect the battery cables. 2. Remove the 4 retaining screws and lift off the plastic engine cover. 3. Tag and disconnect the coil high tension lead, the E-coil connector and the connector at the TFI module, just forward of the throttle body. Move them all out of the way. 4. Tag and disconnect the electrical lead at the ECT sensor, just in front of the TFI module. Unscrew the sensor. To Install: 5. Install the sensor and tighten it to 10-15 ft. Ibs. (13.6-20.3 Nm). Coat the electrical lead with Terminal Grease and reconnect it. 6. Apply Terminal Grease to the lead and two connectors from the module and reconnect them. Confirm that each connection is secure. 7. Install the plastic cover and tighten the screws to 24-36 inch Ibs. 8. Connect the battery cables. 4.1 TESTING See Figures 7 and 11 With the ignition switch in the OFF position, disconnect the electrical lead at the ECT sensor. 2. Measure the resistance across the two terminals in the sensor. 3. Start the engine and allow it to reach normal operating temperature. Check the resistance again. 4. Check the two readings against those in the chart and replace the sensor if they are incorrect. See Figures 12 and 13 The EEC power relay receives direct battery power, protected by a circuit breaker and a fuse, via a electrical lead. Voltage from the ignition switch actuates the relay through a purple lead containing a diode to protect against reverse battery polarity. Finally, the lead carries battery voltage on the ECA at pins 37157. All EEC-IV system components receive power via this lead. REMOVAL INSTALLATION See Figures and 13 1. Open the engine compartment and disconnect the battery cables. 2. Remove the ECA bracket and then disconnect the small vacuum hose to the MAP sensor. 3. Disconnect the electrical leads at the relay. 4. Cut the plastic tie, remove the retaining screw and lift off the relay. 5. Attach the relay to the bracket. Tighten the retaining screw to 24-36 inch Ibs. (2.7-4.1 Nm) and install a new plastic tie. 6. Install the ECA bracket and reconnect the vacuum line. 7. Connect the battery cables. REMOVAL INSTALLATION See Figures 2 and 3 ERATE Turn the ignition key to the OFF position. Do not perform any further steps in this procedure until you have done this. 2. Open the engine compartment and disconnect the battery cables. 3. Locate the ECA on the front side of the engine (Starboard) and cut the plastic tie around the rubber boot. Pull the boot back and remove the Hex screw holding the 60 pin connector on the front of the assembly. Unplug the connector and position it out of the way. 4. Remove the 4 cover retaining screws and then remove the plastic cover and the ECA. To Install: 5. Position the assembly into the plastic cover so that the keyway lines 6. Attach the cover assembly to the bracket and tighten the screws to 24-36 inch Ibs. (2.7-4.1 7. Coat ALL terminal on the 60 pin connector with Terminal Grease and then plug it into the ECA. Tighten the Hex to 46-64 inch Ibs. (5-7 Nm). 8. Stretch the rubber boot over the connector and install a new plastic tie. Connect the battery cables. VREF 46 Rtn Fig. 8 ACT sensor schematic Fig. 9 Typical ECT sensor Fig. 10 The connector is held in place by a lock tab 7 RTN Fig. 11 ECT sensor schematic Fig. 12 EEC power relay Relay Diode Purple Black Black Fig. 13 EEC power relay pin locations 9-10 FUEL SYSTEMS -FUEL INJECTION See Figure 14 All EEC-IV EFI engine utilize an injector firing sequence that OMC calls 'bank-to-bank'-four injectors fire on one revolution of the crankshaft, while the remainina four fire on the next revolution of the shaft. All iniectors receive power via purpleiblack lead from the power relay at ECA 37/57. Ground circuits in the ECA control the actual firing; pin 58 fires the 4, 5 and 8 injectors via the lead, while pin 59 fires the #2, 3, 6 and 7 injectors via the purpleiwhite lead. Fuel injector or circuit will NOT prompt the ECA to store a trouble code in its memory. Fig. 14 Fuel injector schematic REMOVAL INSTALLATION and 6 DERATE See Figures Always have a fire extinguisher handy when working on any part of the fuel system. Remember, a very small amount of fuel vapor in the bilge, has the tremendous potential explosive power. 1. Relieve the fuel pressure as previously detailed. 2. Open the engine compartment and disconnect the battery cables. 3. Remove the upper intake plenum and fuel rail. There is a good chance that the injectors will come up with the rail-if this happens, disconnect the lead and pull the injector out of the holder on the rail. 4. Tag and disconnect the electrical lead at the injector you intend to remove. 5. Grab the body of the injector with your hand and pull it upward while wiggling it back and forth. To Install: 6. Replace the two O-rings on the injector, coating them with a light engine oil before slipping them on. Make sure that they are the fuel resistant type and are Brown in color. Never use silicone grease on the injector O-ring. 7. Install the injector back into the rail the same way you removed it. 8. Install the fuel rail and reconnect the electrical lead to the injector. Make sure you coat both terminals and connector with Terminal grease. 9. Install the upper intake plenum and connect the battery cables. REMOVAL INSTALLATION See Figures and 15 Always have a fire extinguisher handy when working on any part of the fuel system. Remember, a very small amount of fuel vapor in the bilge, has the tremendous potential explosive power. Relieve the fuel pressure as previously detailed. 2. Open the engine compartment and disconnect the battery cables. 3. Remove the upper intake plenum and fuel rail as previously detailed. 4. Remove the 3 Allen screws retaining the regulator and lift it off of the rail. Discard the gasket. To Install: 5. Inspect the O-ring for cracks or other signs of deterioration, replace as necessary. We think it's a good idea to replace the O-ring regardless of condition. Either way, coat it with clean engine oil. Never use silicone grease on the regulator O-ring. 6. Make sure that all residual gasket material is removed from the two mating surfaces and position a new gasket. 7. Install the regulator and tighten the screws to 27-40 inch Ibs. (3.0-4.5 Nm). 8. Install the fuel rail and upper plenum. 9. Connect the battery cables. Fia. 15 Cross section of the fuel reaulator REMOVAL INSTALLATION High Pressure DERATE See Figures 2,3 and 4 Always have a fire extinguisher handy when working on any part of the fuel system. Remember, a very small amount of fuel vapor in the bilge, has the tremendous potential explosive power. All OMC fuel pumps are designed to meet U.S. Coast Guard fuel system regulations. Never substitute and automotive style pump. 1. Open or remove the engine hatchicover and relieve the fuel system pressure as detailed previously. Disconnect the battery cable. 2. Locate the pump at the rear of the engine, on top of the fuel separator. 3. Make a note of the fitting elbow positioning and then hold the elbow while removing the fuel line; be sure to have some rags handy to catch any spilled fuel and make sure you plug the line before moving it out of the way. FUEL SYSTEMS -FUEL INJECTION 1 4. With your wrench still on the elbow, back off the lock nut with another wrench. The lock nut is the nut immediately inside of the elbow; do not confuse it with the end cap nut on the end of the pump. Unscrew the elbow from the end of the pump and set it aside. 5. Remove the 2 screws securing the end bracket to the reservoir and then remove the bracket from the pump. 6. Remove the banjo nut from the end of the pump and then remove the pump. Discard all O-rings. To Install: 7. Lubricate new O-rings with clean engine oil. Slide the small one onto the elbow fitting (right up against the flange) and the larger one onto the banjo nut so it in the groove on the inner side of the head. 8. Slide the banjo nut into the hole on the reservoir cover. Coat another new O-ring with clean engine oil and position it over the threads and up against the bracket. 9. Position the pump at a 45" angle, hold the end cap with a wrench and thread the banjo nut into the pump. Tighten it to 18-22 ft. Ibs. Nm). Be very careful to hold the end cap while tightening the banjo nut or you risk damaging the internal O-ring. 10. Position the support bracket over the other end of the pump and tighten the screws to 25-35 inch Ibs. Nm). 11. Screw the elbow fitting into the end of the pump so that it is in the same position as when removed. Cinch the lock nut down against the pump outlet and then tighten it to inch Ibs Nm) while holding the pump end cap. 12. Install the fuel line and connect the battery cables. Low Pressure See Figures 2,3 and 4 Always have a fire extinguisher handy when working on any part of the fuel system. Remember, a very small amount of fuel vapor in the bilge, has the tremendous potential explosive power. All OMC fuel pumps are designed to meet U.S. Coast Guard fuel system regulations. Never substitute and automotive style pump. Open or remove the engine hatchlcover and relieve the fuel system pressure as detailed previously. Disconnect the battery cable. 2. Position a container under the pumplfilter assembly and remove the inlet line at the filter bracket and the outlet line at the top of the pump. It is important to use two open-end wrenches; one to hold the fuel fitting nut or elbow and the other to loosen the line nut. Plug the line with a golf tee or something similar to prevent additional fuel spillage (OMC actually sells a plug for this purpose). Take care not to spill fuel on a hot engine, because such fuel may ignite. 3. Cut the plastic tie holding the electrical leads to the body of the pump. Unplug the electrical harness at the pump suppressor connector and move it out of the way. 4. Hold the pump end cap (just under the lower edge of the upper retaining bracket) with a wrench while loosening the lock nut (on top of bracket, under elbow). Unscrew the upper elbow. Not holding the end cap while loosening the lock nut will damage the internal O-ring, causing fuel leakage during operation. 5. Remove the 2 fuel filter bracket mounting bolts and lift off the as an assembly, sliding the pump out of the upper grommet. Be careful of spilling fuel. 6. Lay the assembly down, or carefully mount the bracket in a vise. Hold the lower pump end cap with a wrench and unscrew the filter bracket. to-pump adapter. Not holding the end cap while loosening the lock nut will damage the internal O-ring, causing fuel leakage during operation. To Install: 7. Slide a new O-ring over the threads of the adapter until it rests on the upper side of the hex nut. -- 8. Screw the adapterlbracket assembly into the pump while holding the lower end cap. Tighten the adapter to 8-10 ft. (11-14 9. Slide the assembly up through the grommet in the bracket and position it so the mounting holes line up on the bracket. Tighten the filter bracket bolts to 20-25 ft. Ibs. (27-34 Nm). 10. Thread the upper lock nut onto the elbow until it reaches the underside of the fitting. Slip on the washer and then a new O-ring. Thread the elbow into the top of the pump until it stops and then back it out just enough to align with the fuel line. Connect the line and tighten it securely. 11. Hold the upper end cap again and tighten the lock nut to inch Ibs. Nm). 12. Reconnect the suppressor lead-push it in until the tabs click. If you notice any of the suppressor holes open, be sure to coat them with Liquid Neoprene to prevent water from entering. 13. Install a new plastic tie around the pump body and electrical leads. 14. Reconnect the inlet line and tighten it securely. 15. Install the pump guard if removed. 16. Remove the container and connect the battery cables. Start the engine and check for fuel leaks. REMOVAL INSTALLATION DERATE 4 See Figure 4 Always have a fire extinguisher handy when working on any part of the fuel system. Remember, a very small amount of fuel vapor in the bilge, has the tremendous potential explosive power. Open or remove the engine hatchicover and relieve the fuel system pressure as detailed previously. Disconnect the battery cable. 2. Remove the upper intake body assembly as detailed previously. 3. Clean any and all debris from around the rail and injectors to prevent it from falling into the intake ports. 4. Carefully disconnect the fuel supply line at the rear Port side of the rail. Do the same with the return line on the Starboard side. Plug the lines and make sure you have plenty of rags available to mop up the inevitable spillage. 5. Make a note of the injector harness positioning on the rail and where it is secured. Cut the plastic ties securing the harness to the rails. 6. Remove the 4 rail retaining bolts (2 per side), carefully disengage the rails from each injector and lift off the rail. An alternate way is to simply remove the rail with the injectors attached, and then remove the injectors if necessary-we like this way better, particularly if you do not intend on replacing the rail or injectors. Cover the injector holes. To Install: 7. If the injectors were removed, confirm that the caps are clean and debris-free. 8. Replace the two O-rings on each injector, coating them with a light engine oil before slipping them on. Make sure that the O-rings are the fuel resistant type and are Brown in color. No you don't have to replace the rings if they are in good condition, but why would you not do it while you've got the injectors out?? Cheap insurance, and can save you a lot of headache and time down the road. Never use silicone grease on the injector O-ring. 9. If you left the injectors in position, seat each one into the rail cup, making sure the O-ring snaps into place. Otherwise, position the assembly over the ports and carefully pop the injectors into place. Once everything is in position, install the retaining bolts and tighten them to 70-105 inch Ibs. Nm). Reroute the injector harness so that it approximates the original positioning and then install new plastic ties where you had removed the old ones. Make sure that all terminals and connections have been coated with Terminal Grease. 11. Install the manifold and throttle body assembly. 12. Connect the battery cables. 9-12 FUEL SYSTEMS -FUEL INJECTION REMOVAL & INSTALLATION DERATE See Figures 2,3 and 4 Always have a fire extinguisher handy when working on any part of the fuel system. Remember, a very small amount of fuel vapor in the bilge, has the tremendous potential explosive power. 1. Open or remove the engine and relieve the fuel system pressure as detailed previously. Disconnect the battery cable. 2. Loosen the hose clamps and then remove the water inlet and outlet hoses from the tank. 3. Remove the power steering cooler retaining bracket bolt and position the cooler out of the way. There is a special flat washer behind the cooler bracket-don't lose it when lifting off the assembly. 4. Clip the plastic tie securing the pump harness to the pump and then unplug the connector and move the harness out of the way. 5. Remove the small clamp and wiggle the vent hose from the nipple at the rear of the reservoir. Position it out of the way. 6. Remove the fuel inlet line from the low pressure pump. Remove the line running between the reservoir and pressure regulator. Remove the high pressure pump outlet line. Please refer to the Fuel Pump procedures for specific details on removing the fuel lines. 7. Loosen the clamp and remove the cooling outlet line (running to the thermostat housing) connected to the elbow on the Starboard side of the reservoir. 8. Remove the 2 mounting bolts at the bottom of the reservoir and lift off the assembly. To Install: 9. Adjust the float level as detailed later in this section. 10. Position the reservoir onto the engine and tighten the mounting bolts to 24-36 (38-49 Nm). 11. Reattach the coolant line to the elbow on the reservoir and tighten the clamp securely. 12. Connect the three fuel lines to the pump and reservoir as detailed in the Fuel Pump section. 13. Connect the vent line running from the upper manifold and tighten the clamp securely, but not so tight as to pinch the hose. 14. Coat the terminals on the fuel pump and pump harness connector with Terminal Grease and plug the connector into the pump. Secure the harness to the pump body with a new plastic tie. 15. Slide the flay washer over the mounting stud on the rear of the reservoir and then install the power steering cooler. Tighten the lock nut to Ibs. Nm). 16. Reconnect the cooling hoses and tighten their hose clamps securely. 17. Connect the battery cables. FLOAT LEVEL See Figures 4 and 16 1. Disconnect all fuel and remove the high pressure fuel pump. 2. Remove the 8 reservoir cover retaining screws and lift off the cover and pump brackets. Discard the gasket. 3. Flip the cover assembly over and allow the float to drop down until it seats the float needle. 4. Measure the distance between the bottom edge of the inverted float (actually the top edge when installed in the reservoir) and the inner mounting surface of the reservoir cover. 5. Bend the float adjustment tab very carefully until the gap is 3/16 in. Rotate the assembly once or twice and check that the float moves freely and that the gap has not changed. Never force the float needle tip against the seat or you will damage the special tip. 6. Position a new cover gasket onto the reservoir and then carefully install the cover assembly. Tighten the retaining screws to 25-35 inch Ibs. (2.8-4.0 Nm). 7. Install the fuel pump and reconnect the fuel lines. Tab 16 Adjust the float level with the reservoir cover inverted See Figures 17 and 18 The idle speed control by-pass air solenoid receives battery voltage via the lead from ECA pins 37/57. Ground is via the ground wire from the ECA. This ground circuit serves to control voltage to the solenoid; the varying voltage then changes the position of the air by-pass valve. The greater the voltage, the more air will be allowed to bypass the throttle plate. REMOVAL & INSTALLATION 4 See Figures 2,3 and 4 Open or remove the engine hatchicover and relieve the fuel system pressure as detailed previously. Disconnect the battery cable. Tag the 2-pin connector at the rear of the ISC solenoid and disconnect it from the solenoid. The solenoid is attached to the aft side of the throttle body. 3. Remove the 2 solenoid retainina screws and it off the adaotor Discard the gasket. 4. Remove the 2 adaptor retaining screws and pull it off the throttle body. Discard the gasket. Pull the small muffler out of the adaptor body. To Install: 5. Carefully wash the muffler in solvent and allow it to air dry. 6. Clean any residual gasket material from both sides of the adaptor, and from the throttle body and solenoid mating surfaces. 7. Insert the muffler into the adaptor so that is flush with, or below, the surface. 8. Position a new gasket onto the throttle body and then install the adaptor. Tighten the screws to inch (8-11 Nm). 9. Position a new gasket onto the adaptor and install the solenoid. Tighten the screws to 71-102 inch Ibs. (8-11 Nm). 10. Coat all terminals of the connector with Terminal Grease and reconnect the lead to the solenoid. 11. Install the engine cover and connect the battery cables. See Figures 19 and 20 At the first sign of spark knock, a pulsing signal is produced by the sensor and then sent through an amplifier to the ECA. After receiving this signal, the ECA will retard timing in three steps (but no more than from the starting point) until knock is no longer sensed by the sensor. Once the MAP sensor detects a 3-4 in. Hg. change in engine vacuum, or the engine is shut off, the ECA will return the engine to its normal spark advance. REMOVAL INSTALLATION See Figure 19 Open or remove the engine hatchicover and relieve the pressure as detailed previously. Disconnect the battery cable. FUEL SYSTEMS -FUEL INJECTION 9-13 Fia. 17 ISC solenoid ISC solenoid schematic 2. Locate the knock sensor on the rear of the cylinder block, just above the flywheel housing and behind the port side leg of the separator reservoir. Tag and disconnect the electrical lead at the sensor and then unscrew the sensor. The sensor is fragile and must be handled with care. If it is dropped, or banged in any manner, you must replace it. 3. Working right next to the sensor, cut the plastic tie around the amplifier and pop it out of its bracket. Pry off the retainer and then unplug the amplifier connector. To Install: 4. Coat all terminals with Terminal Grease and plug in the amplifier connector. Press the retainer into position. Position the amplifier on the bracket and secure it with a new plastic tie. 5. Thoroughly clean the threads of the knock sensor and its hole. The sensor grounds through the threads, so there can be no residual paint or dirt. Carefully screw the sensor in and tighten it to 7-10 Ibs. (9.5-13.5 Nm). Pin D (Yellow) Amplifier Pin A (Black),. I 37/57Sensor Fia. 20 KS schematic DO NOT OVER-TIGHTEN THE KNOCK SENSOR. 6. Attach the sensor lead and connect the battery cables. See Figure and 23 The MAP sensor is a pressure transducer capable of measuring the changes in the intake manifold pressure. Pressure changes are the result of engine load and speed changes. MAP is the opposite of what is measured with a vacuum gauge. When manifold pressure is high, vacuum is low-requires more fuel and of course the opposite is true. A low pressure-higher vacuum requires less fuel. The MAP sensor is also used to measure barometric pressure under certain conditions. This feature permits the ECM to automatically adjust for changes in operating altitude. The ECM uses the MAP sensor to control fuel delivery and ignition timing. Reference voltage (VREF) is supplied to the sensor via a brownlyellow lead from the ECA. The sensor then outputs a frequency signal back to the ECA via the greenlblack lead and the circuit is completed with a signal return (SIG RTN) from the ECA to the sensor via the lead. REMOVAL INSTALLATION See Figures 2,3 and 5 1. Open or remove the engine hatchicover and relieve the fuel pressure as detailed previously. Disconnect the battery cable. 2. Remove the Self-Test connector and cover from the top of the ECA bracket just forward of the Starboard exhaust elbow. 3. Remove the 3 ECA bracket mounting screws. 4. Loosen the small hose clamp and pull the vacuum line off the nipple on the sensor. Tag the line and position it out of the way. Remove the sensor filter at the other end of the line and clean it in a mild solvent, Fin. 21 MAP sensor Fig. 22 MAP sensor schematic Manifold Vacuum Frequency in. Ha Hz Fig. 23 MAP sensor data table 9-14 FUEL SYSTEMS -FUEL INJECTION 5. Tag the sensor lead and disconnect it from the sensor body. 6. Remove the 2 retaining screws and pull the sensor off the bracket. To Install: 7. Attach the sensor to the ECA bracket so that the flat side is facing up (toward the bracket). Tighten the screws to 24-36 inch Ibs (2.7-4.1 Nm). It is very important that the sensor is installed upside down to prevent condensation damage. lnstall the sensor filter into the vacuum lines so that the arrow is pointing toward the sensor. Slide the vacuum line onto the sensor nipple and tighten all clamps securely. You may find it easier to connect the sensor terminal first. 9. Coat the connector terminals with Terminal Grease and snap together the connection. 10. Position the ECA bracket on the engine and tighten the screws to 60- 84 inch Ibs. (6.8-9.5 Nm). 11. Attach the Self-Test connector and cover. Connect the battery cables. REMOVAL INSTALLATION See Figures 5 and 24 Open or remove the engine hatchicover and relieve the fuel system pressure. Disconnect the battery cable. 2. Remove the 4 screws and lift off the plastic engine cover. 3. Remove mounting and then remove the flame arrestor. Certain models will have a bracket holding the arrestor on. 4. Remove the throttle cable locknut at the arm on the throttle body and then disconnect the throttle linkage. 5. Tag and disconnect the wiring harness for the ISC solenoid and TP sensor. 6. Remove the 4 throttle body mounting nuts. Lift out the throttle body and set it down in a holding fixture to avoid damage to the valves. Stuff a clean, lint-free rag into the plenum opening. 7. Remove the TP sensor and ISC valve with their O-rings from the assembly if necessary. 8. Lift the coil bracket off of the studs. To Install: 9. Carefully clean the throttle bore and valve. Do not use anything containing methyl ethyl ketone! If you didn't remove the TP sensor and valve, make sure that you get no solvent on them during cleaning. CAREFULLY scrape any gasket material off the mating surfaces. Make sure all passages are free of dirt and completely dry before installation. The inside of the throttle bore and the back (inner) side of the throttle valve have been coated with a special protective material which created a ridge at the point that the valve meets the bore--do not remove this ridge, or spray any kind of cleaner on the surfaces. 10. Slide a new gasket over the studs in the manifold so that the tab is at the bottom and facing rearward. Slide on the coil bracket. 11. Install the sensor and valve into the throttle body if they were removed. 12. Position the throttle body and new gasket (tab at bottom and facing the rear) over the studs and tighten the nuts to 12-18 ft. Ibs. Nm). 13. Connect the IAC and TP leads. 14. Connect the throttle cable and adjust as necessary. 15. lnstall the flame arrestor and engine cover. 16. Reconnect the battery cables. See Figures and 27 The TP sensor is a potentiometer connected to the throttle shaft on the throttle body. One end of the sensor is connected to a 5-volt reference signal (VREF) from the ECA via a brownlyellow lead and the other end is connected to ECA ground. A third wire (greylwhite) is connected directly to the ECM to measure the voltage from the TP sensor. The voltage output of the TP sensor changes when the throttle valve angle is changed. The circuit is completed when the signal is returned (SIG RTN) via the greylred wire. Thottle Cable \ Lock Nut Fig. 24 Disconnect the throttle cable and move it out of the way When the throttle position is closed, the voltage output of the TP sensor is low-about 112 volt. When the throttle valve is opened, the output increases and at WOT the output voltage should be close to 5 volts. Therefore, the ECM can determine fuel delivery requirements based on throttle valve angle--operator demand. REMOVAL INSTALLATION See Figures 2,3 and 5 1. Open or remove the engine and relieve the fuel system pressure. Disconnect the battery cable. 2. Remove the 4 screws and lift off the plastic engine cover. 3. Remove mounting and then remove the flame arrestor. 4. Tag and disconnect the electrical connector at the sensor and move it out of the way. 5. Using a magic marker, draw a line across the body of the sensor and the throttle body to use as a reference mark on installation. 6. Unscrew the 2 mounting screws and remove the sensor. Clean the sensor with a dry cloth; make sure that the sensor is in good condition (no wear, cracks or damage), if not replace it. If replacing the sensor with a new one, make sure to use the two new screws that came with the package. 7. Install the sensor so that the wiring harness would be laying across flame arrestor. Rotate the sensor clockwise until the reference mark made earlier lines up and tighten the screws to 18-26 inch Ibs. (2-3 Nm). 8. Coat the connector terminals with Terminal Grease and then plug them together. 9. Install the flame arrestor and cover. Connect the battery cables. See Figure 28 The following system checks and tests MUST be followed in the order that they are presented so that system diagnosis can be properly exercised. SYSTEM INTEGRITY CHECK 1. Inspect the entire fuel delivery system for leaks, looseness, corrosion, grounding or other damage. Be certain to check: Fuel tank and lines Fuel filter Fuel pumps Fuel injectors Pressure regulator All electrical connections and lines Vapor Separator 2. Repair or replace any component not standing up to the inspection. 3. If the fuel delivery system shows no evidence of damage, etc., proceed to the Fuel Injection Pressure Test. FUEL SYSTEMS -FUEL INJECTION 9-15 Fig. 25 TP sensor 26 46 RTN) Throttle Angle Voltage A Voltage values calculated for VREF 5V and may vary +I-15% due to variations SYMPTOM CHART CHECKS TO BE PERFORMED Fuel Throttle Ignition Electrical Cooling Engine Air Check the throttle linkage and cable for binding Check stern drive oil. Possible drive bearing problems Check hull for marine growth Check fuel tank, vents and fuel lines for leaks Fig. 28 SYMPTOM System Injectors Body Sensors System System Mechanical Intake Other X X X Cranking Will Not Crank Cranks But Does Not Run Hard To -Long Cranking Time X X XX X X X X X X X X X FUEL INJECTION PRESSURE TEST See Figure 29 With the ignition switch in the OFF position, install a fuel pressure gauge at the pressure valve on the fuel rail. 2. Ground the fuel pump lead at the (Self-Test Output) connector (pin 3. Turn the ignition switch to the ON position (but do not start the engine) so that the fuel pumps are energized. 4. If the gauge reads 36-42 psi (248-290 proceed to the Fuel Pressure Test. 5. If the gauge reads or very low, proceed to Checking Voltage At FP Relay. 6. If the gauge shows the pressure to be high, proceed to Checking the Regulator For High Pressure. FUEL PRESSURE TEST See Figure 29 With the ignition switch in the OFF position, install a fuel pressure gauge at the pressure valve on the fuel rail. 2. Connect a jumper wire to the lead at the Self-Test connector (pin 3. Turn the ignition switch to the ON position (but do not start the engine). Connect the jumper lead from the previous step to a suitable ground, run the fuel pumps for 30 seconds and then disconnect the jumper. 9-16 FUEL SYSTEMS -FUEL INJECTION Take note of the fuel pressure reading on the gauge. 4. The pressure should remain within 3 psi of the running pressure for at least 3 minutes after the jumper is removed from ground. 5. If the pressure held, proceed to Pressure Regulator Diaphragm Check. 6. If the pressure did not remain constant, proceed to Pressure Regulator Valve Seat Check. PRESSURE REGULATOR DIAPHRAGM CHECK CULT With the ignition switch in the OFF position, install a fuel pressure gauge at the pressure valve on the fuel rail. 2. Start the engine and allow it to run for 10 seconds. Turn it off for seconds and then start it again and allow it to run for another 10 seconds. 3. Turn off the engine and disconnect the vacuum line at the regulator. 4. Examine the port and regulator body for signs of leakage. 5. If no fuel is present, proceed to Fuel Pressure Under Load Check. 6. If fuel leakage is present, replace the regulator and then perform the Fuel Injection Pressure Test again. FUEL PRESSURE UNDER LOAD CHECK CULT With the ignition switch in the OFF position, install a pressure gauge at the pressure valve on the fuel rail. 2. Start the engine and allow it to idle. 3. Disconnect the vacuum line at the pressure regulator. If the line has vacuum, plug it. Otherwise, determine why there is no vacuum, fix the problem, and then plug the line. 4. Run the engine up to full throttle and then back to idle at least 4 or 5 times while checking the fuel pressure gauge. 5. If the fuel pressure remains within 3 psi of itself across all readings, unplug the vacuum line and reconnect it. 6. If the pressure readings vary more than 3 psi, proceed to Fuel Filter Check. FUEL PRESSURE REGULATOR CHECK CULT With the ignition switch in the OFF position, install a fuel pressure gauge at the pressure valve on the fuel rail. 2. Install a "T" in the vacuum line running from the regulator and the upper plenum. a vacuum gauge to the "T". 3. Start the engine and check both the pressure and vacuum gauges. 4. Increase the engine speed so that the vacuum level falls and check the pressure gauge. 5. If the fuel pressure increases as you accelerate and the vacuum decreases; and, if it decreases as you decelerate while the vacuum begins to increase, remove the gauges. 6. If the vacuum and pressure reading do not act inversely to one another, proceed to Vacuum Supply Check. VACUUM SUPPLY CHECK CULT With the ignition switch in the OFF position, install a pressure gauge at the pressure valve on the fuel rail. 2. Disconnect the vacuum line at the pressure regulator and plug it. 3. Connect a hand-operated vacuum pump to the regulator at the nipple. 4. Start the engine and check the fuel pressure while pumping the vacuum pump. 5. If the pressure reading changes as the vacuum changes, service the vacuum system and reconnect the vacuum line to the regulator. 6. If the fuel pressure does not change, replace the regulator. FUEL PUMP RELAY VOLTAGE CHECK See Figure 29 With the ignition switch in the OFF position and the battery fully charged, ground the fuel pump lead at the Self-Test connector (pin 2. Connect a DVOM to the fuel pump relay. 3. Turn the ignition switch to the ON position (but do not start the engine). Measure the voltage at the relay. 4. If voltage is more than look for an open circuit between the relay and the ECA. 5. If voltage less than proceed to Fuel Pump Relay Power Supply Check. FUEL PUMP RELAY POWER SUPPLY CHECK See Figure 30 CULT With the ignition switch in the OFF position and the battery fully charged, disconnect the electrical leads and remove the relay. 2. Turn the ignition switch to the ON position (but do not start the engine). Measure the voltage between the ground terminal in the relay connector (black lead, pin and both pins lead, pin #30 and purplelblack lead, pin 3. If voltage on both pins is higher than proceed to Fuel Pump Relay Operation Check. 4. If voltage is not higher than check for a crimped or torn wire between the pump relay and the EEC power relay or the battery (t). FUEL PUMP RELAY OPERATION CHECK TE See Figure 30 Remove the relay from the bracket. 2. Ground terminal #86 with a jumper wire and then connect a Bt 12V power supply to Measure the resistance between and 3. Resistance should be less than 1 ohm with the power source supplied and greater then 10,000 ohms when it is removed. 4. If not, replace the fuel pump relay. FUEL PUMP OPERATION CHECK See Figure 29 With the ignition switch in the OFF position and the battery fully charged, ground the fuel pump lead at the Self-Test connector (pin 2. Turn the ignition switch to the ON position (but do not start the engine). You should be able to hear the fuel pumps and also feel a slight vibration to the touch. 3. If they are working, proceed to Fuel Filter Check. 4. If they are not working, check that the 20 amp circuit breaker is operating and the wiring is good. If everything is OK, proceed to Fuel Pump Voltage Check. Fig. 29 connector pin locations FUEL SYSTEMS -FUEL INJECTION 9-17 FUEL PUMP VOLTAGE CHECK DERATE See Figure 29 With the ignition switch in the OFF position and the battery fully charged, ground the fuel pump lead at the Self-Test connector (pin 2. Disconnect the electrical leads at the two fuel pumps. 3. Turn the ignition switch to the ON position (but do not start the engine). 4. Measure the voltage at the power supply leads at each pump. If greater than at each pump, proceed to Fuel Pump Ground Check. 5. If voltage is less than check the circuit between the ECA and the fuel pump connector and then proceed to Fuel lnjection Pressure Test. FUEL PUMP GROUND CHECK CULT With the ignition switch in the OFF position and the battery fully charged, disconnect the electrical leads at the two fuel pumps. 2. Measure the resistance between the black wire terminal and ground. 3. If each pump is less than ohm, replace the pumps and then proceed to Fuel lnjection Pressure Test. 4. If more than 1 ohm, check for an open wire to ground and then proceed to Fuel lnjection Pressure Test. FUEL FILTER CHECK 1. Remove the fuel filter and check its condition and also for water. 2. If the filter requires replacement, proceed to Fuel Pump Ground Check. 3. If the filter is OK, reinstall it and repeat the Fuel lnjection Pressure Test. PRESSURE REGULATOR VALVE SEAT CHECK CULT Visually check the O-ring, gasket, mounting surfaces and regulator body for cracks or damage. 2. Connect a vacuum tester to the fuel outlet on the regulator and apply 20 in. Hg of vacuum. 3. If the vacuum drops below 10 in. Hg within seconds, replace the regulator and then repeat the Fuel lnjection Pressure Test. 4. If vacuum stays within specifications, proceed to Fuel lnjector Function Check. PRESSURE REGULATOR PRESSURE CHECK CULT With the ignition switch in the OFF position and the battery fully charged, remove the fuel return line at the fuel rail and the vapor separator. 2. Install a clear, fuel resistant, hose between the rail and the reservoir. 3. Install a fuel pressure gauge at the pressure valve. Fig. 30 Fuel pump relay pin locations 4. Ground the fuel pump lead as detailed in the Fuel lnjection Pressure Check. 5. Turn the ignition switch to the ON position (but do not start the engine). 6. Note the fuel pressure reading and confirm that fuel is being returned to the reservoir through the clear tube. Do not keep the pump lead grounded for more than 10 seconds. 7. If the pressure is still higher than 36-42 psi (248-290 replace the pressure regulator and then repeat the Fuel lnjection Pressure Test. 8. If pressure is no longer high, proceed to the Fuel Return System Check. ERATE Check the fuel return lines for blockage or kinking. 2. Remove the return line at the pressure regulator and apply 3-5 Ibs. of compressed air to the line. 3. If you hear air entering the reservoir, reconnect the line. 4. If no air can be heard entering the reservoir, proceed to the Fuel Return System Check. FUEL RETURN SYSTEM CHECK 1. With the ignition switch in the OFF position and the fully charged, remove the fuel return line at the pressure regulator and the vapor separator reservoir. 2. Apply 3-5 of compressed air to the line at the regulator. 3. If air flows freely through the line, service the reservoir. 4. If air does not flow through the line, replace it or attempt to clear the blockage. lnstall the line and repeat the Fuel lnjection Pressure Check. FUEL INJECTOR FUNCTION CHECK With the engine at normal operating temperature and idling, check that you can hear each injector pulsing with a mechanic's stethoscope. If the engine will not start, perform this step with the engine cranking. 2. If you can detect that the injectors are operating, proceed to Fuel lnjector Check. 3. If they are not working, proceed to Fuel lnjector Resistance Check. FUEL INJECTOR RESISTANCE CHECK DERATE 1. With the ignition switch in the OFF position and the battery fully charged,, disconnect each injector connector individually. 2. Check that the resistance on each injector is 13-16 ohms. 3. If within range, proceed to Fuel lnjector Continuity Signal Check. 4. If outside the range, replace the injector. FUEL INJECTOR CONTINUITY CHECK 1. With the ignition switch in the OFF position and the battery fully charged, disconnect any injector lead on bank 2. Connect a 12V test light to the terminal in the connector and then touch the probe to the other connector terminal. 3. Start the engine and observe whether the test light blinks or not. Obviously, if the tester lights, then the circuit has been completed. 9-18 FUEL SYSTEMS -FUEL INJECTION 4. Repeat this procedure for bank 2. 5. If the circuit has been completed, proceed to Fuel Injector Check. 6. If the circuit does not indicate continuity on either bank, go back and test each injector connector on that bank. Service or replace the individual lead as necessary. FUEL INJECTOR CHECK Using a Fuel Injector clean and test the injectors. Now clean them once more. Match the color range on the tester the top color of the injector and confirm that the flow rate is within specifications. 2. Check for any appreciable pressure drop while the special tool is connected to the system, either due to leakage or turning the unit off. 3. Check injector leak rate using the tool, anything over 1 droplmin. is too much. 4. If flow and leak rates were within specification, check all fuel lines for leaks. If all lines are OK, replace the fuel pump assembly and then repeat the Fuel Injection Pressure Check. 5. If either were out of specification, replace any defective injectors and then repeat this test and the Fuel Pressure Check. No Code--Loss of VREF Code 10-Vapor Separator Code 11-System Pass Code 12-RPM outside Self-Test upper band limit Code 13-RPM outside Self-Test lower band limit Code 14--PIP circuit fault Code 15-ROM test power in continuous (1993) Code 15-ROM test power interrupt (1994-96 Code 18-Loss of TACH input to circuit grounded Code 19-Failure in EEC reference voltage Code 21-ECT out of Self-test range Code 22-MAP out of Self-test range Code 23-TP out of Self-test range Code 24--ACT out of Self-test range Code 25-Inactive Ignore code Code indicated. ECT sensor circuit open Code 52-Shift assist circuit Code 53-TP circuit above maximum voltage Code indicated. ACT sensor circuit open Code 61-254" indicated. ECT sensor circuit grounded Code 63-TP circuit below minimum voltage Code 64-254" indicated. ACT sensor circuit grounded Code 67-NDS circuit open Code 72-Insufficient MAP change DYN RSP test Code 73-Insufficient TP change DYN RSP test Code 77-Operator error DYN RSP test Code 87-Fuel pump circuit failure Code 95-Fuel pump circuit open ECA-to-motor ground Code 96-Fuel pump circuit open BAT-to-relay Code 98-FMEM failure GENERAL INFORMATION Electronic Control Assembly (ECA) One portion of the ECA is devoted to monitoring both input and output functions within the system. This ability forms the core of the self-diagnostic system. If a problem is detected within a circuit, the controller will recognize the fault, assign it an identification code, and store the code in memory. All codes are 2-digit numbers and may be retrieved during diagnosis. While the EEC-IV system is capable of recognizing many internal faults, certain faults will not be recognized. Because the computer system sees only electrical signals, it cannot sense or react to mechanical or vacuum faults that may affect engine operation. Some of these faults though may affect another component which will set a code. For example, the ECA monitors the output signal to the fuel injectors, but cannot detect a clogged injector. As long as the output driver is responding correctly, the computer will read the system as functioning properly. However, the improper fuel will probably result in a lean mixture. This could, in turn, be detected by the knock sensor and then noticed by the ECA. Once the signal falls outside the pre-programmed limits, the ECA would notice a fault and then set a code. Failure Mode Effects Management {FMEM) The ECA contains back-up programs which allow the engine to operate if a sensor signal is lost. If a sensor input is seen to be out of range--either high or low-the FMEM program kicks in. The processor substitutes a fixed value for the missing sensor signal. The engine will continue to operate, although performance and driveability may be noticeably reduced. This function of the controller is sometimes referred to as the limp-home or fail- safe mode. If the missing sensor signal is restored, the FMEM system immediately returns the system to normal operation. When this cycle is in effect, the Self-Test function will show a service code 98. The error code associated with a particular fault will be stored in the Keep Alive Memory (KAM). If the fault is no longer detected, the engine will return to normal operating mode and the code will then be stored in Continuous Memory for the next 40 engine cycles before it is erased. HAND-HELD SCAN TOOLS See Figure 31 Although codes may be read through the flashing of the light, the use of hand-held scan tools like the OMC MFI Tester or an equivalent is recommended. There are aiternate manufacturers of these tools so be certain that the tools is correct for your intended use and application. The scan tools allows any stored fault codes to be read from the ECA memory. Use of the scan tool also provides additional data during troubleshooting, but does not eliminate the use of charts. Scan tools make data collection much easier, but the data must be correctly interpreted by an operator familiar with the system. Fig. 31 OMC MFI tester ELECTRICAL TOOLS See Figure 32 The most commonly required electrical diagnostic tool is the digital multi- meter (DVOM); allowing voltage, (resistance) and amperage to be read by one instrument. Many diagnostic tests require the use of a volt or ohmmeter during diagnosis. The multi-meter must be a high impedance unit, with megohms of impedance in the voltmeter. This type of meter will not place an additional load on the circuit being tested-extremely important when testing low voltage circuits. The multi-meter must be of high quality in all respects. It should be handled carefully and protected from impact or damage. Replace the batteries frequently. Additionally, an analog (needle-type) voltmeter may be used to read stored fault codes if the MFI tester is not available. Codes will be transmitted as visible needle sweeps on the face of the instrument. Almost all diagnostic procedures will require the use of a Breakout Box, a device which connects to the EEC-IV harness and provides testing ports for FUEL SYSTEMS -FUEL INJECTION 9-19 Fig. 32 OMC Breakout Box the 60 wires in the harness. Direct testing of the harness connectors at the terminals or by back-probing is not recommended; damage to the wiring and terminals is almost certain to occur. Other necessary tools include a quality tachometer with inductive pick-up, a fuel pressure gauge with system adaptors and a vacuum gauge with an auxiliary source of vacuum. READING CODES Diagnosis of a problem requires attention to detail and following the diagnostic procedures in the correct order. Always resist the temptation to begin extensive testing before completing the preliminary diagnostic steps. The preliminary or visual inspection must be completed in detail before the diagnosis begins. In many cases this will shorten diagnostic time and often cure the problem without electronic testing. Visual Inspection This is possibly the most critical step of all diagnosrs. A of all connectors, wiring and vacuum hoses can often lead to a repair without further diagnosis. Performance of this step relies heavily on the skill of the person performing it; a careful inspector will inspect the underside of all hoses as well as the integrity of hard-to-reach hoses blocked by other components. All wiring should be checked carefully for any signs of strain, burning, crimping or terminal pull-out from a connector. Checking connectors at components or in harnesses is required; usually pushing them together will reveal a loose fit. Pay particular attention to ground circuits, making certain they are not loose or corroded. Remember to check connectors and hose fittings at components not mounted on the engine. Any component or wiring in the vicinity of a fluid leak or spill should be given particular attention during inspection. Additionally, inspect maintenance items such as belt condition and tension, battery charge and condition, and the radiator cap. Any of these items can easily set off a condition that will create a fault code. Electronic Testina If a code was set before a problem was self-corrected (such as a momentarily loose connector), the code will be erased if the problem does not re-occur within 40 engine cycles. Codes will be output and displayed as numbers on the hand-held tester. In all cases, the code 11 is used to indicate PASS during testing. Please note that the PASS code may appear followed by other stored codes. These are codes from the Continuous Memory and may indicate faults, even though the system does not presently contain the fault. The PASS designation only indicates that the system passes all internal tests at the moment. Key On Engine Off (KOEO) Test The engine must be a normal operating temperature before performing this test and all visual checks should be completed. Connect the MFI Tester to the and connectors on top of the ECA cover. 2. Set the Mode switch on the tester to the FAST position. 3. Set the SPKR switch on the tester to the OFF position. 4. Set the button to the HOLD position (rased). 5. Turn on the PWR switch. It should beep once and then briefly display 888 and then settle in at 000. 6. Turn the ignition key to the ON position, but do not start the engine. 7. Press the button down to put the ECA into the Self-Test mode. After approximately 1 minute, any codes should begin to appear on the screen. Do not press the button again while the system is in Self- Test mode or you will erase all Continuous Memory codes. 8. Self-Test is complete when CCRCVD appears in the window. Press the button again to release it and lock all codes into the tester's memory. 9. Turn the ignition key to OFF. 10. You can use the and MEMREV buttons to review the codes stored in the tool's memory. The first code will always be proceeded by a "beep" and the CD prompt. Always review codes in the EXACT order in which they have been displayed. Key On Engine Running (KOER) Test The engine must be a normal operating temperature before performing this test and all visual checks should be completed. Connect the MFI Tester to the and connectors on top of the ECA cover. 2. Set the Mode switch on the tester to the FAST position. 3. Set the SPKR switch on the tester to the OFF position. 4. Set the button to the HOLD position (raised). 5. Turn on the PWR switch. It should beep once and then briefly display 888 and then settle in at 000. 6. Start the engine and allow it to idle for seconds prior to moving on to the next step. 7. Press the button down to put the ECA into the Self-Test mode. After 2 minutes. anv service codes should beain to appear on the screen. the first minute, the system will actuate "High Idle" Self-test so you can confirm the control of timing. If a DYN RSP prompt appears, or a Code 10 appears toward the end of the "High Idle" test, ignore it. Do not press the button again while the system is in Self- Test mode or vou will erase all Continuous Memorv codes. 8. Self-Test is complete when CCRCVD appears in the window. Press the button again to release it and lock all codes into the tester's memory. 9. Turn the ignition key to OFF. 10. You can use the and MEMREV buttons to review the codes stored in the tool's memory. The first code will always be proceeded by a "beep" and the CD prompt. Always review codes in the EXACT order in which they have been displayed. 9-20 FUEL SYSTEMS -FUEL INJECTION CLEARING CODES the purpose of testing or repair confirmation, perform the KOEO test. When the codes are just beginning to come up on the display, Press off the Continuous Memory Codes button and the codes will automatically be erased from the system's memory. Do not disconnect the battery to clear the codes-they'll clear, but in the process set another code 9) for the ECA power loss. As mentioned previously, these codes are normally stored in the ECA memory for a duration of 40 engine warm-up cycles. To clear the codes for Sensors DVOM Black Red Sensor Setting Lead Lead Value Notes VREF. DCV 46. 26 TP DCV 46 47 0.9-1 5V Throttle Closed 4 65V WOT ECT DCV 46 7 0.87-1.1 7V ACT DCV 46 25 1 MAP Hz 46 45 159 Hz PIP DCV 46 56 VBAT KS DCV 46 2 SAS (1 993) DCV 40 0 Not Actuated VBAT Actuated NDS (1 993) 46 30