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SERVICE MANUAL Number 3 MARINE ENGINES Mercury Marine 4 Cylinder GM 4 Cylinder • GM 6 Cylinder GM V-8 Cylinder ©Brunswick Corporation 1988 Printed in U.S.A. 90-95693 1-888 MODELS COVERED IN THIS MANUAL MODEL SERIAL NUMBER MCM 120 4952701 - 6255465 MCM 120R 6255466-6853913 MCM 140 4918570-6256954 MCM 140R 6256955 - 6852269 MCM 165 4884835 and Above MCM 470 4886620-6218036 MCM 470R 6218037-6902287 MCM 485 5685394 and Above MCM 488R 6170297 - 6899057 MCM 898 4887830-6218461 MCM 898R 6218462-6899057 MCM 228 4902305 - 6225266 MCM 228R 6225267 - 6899268 MCM 260 4908850 - 6227756 MCM 260R 6227757 - 6890705 MCM 330 4889680-6083144 MCM 330 (B-W) 6083145-6920831 MCM 370/400 4883520-6721534 MCM 400 Cyclone 5669232 - 6844266 MCM 440 Cyclone 6181070 -OA429860 MCM 460 Cyclone 6180970-6181039 MCM 475 Turbo 5670797 and Below MCM 470TR All (Note 1) MCM 230TR 6901029 and Below (Note 1) MCM 260TR 6885891 and Below (Note 1) MIE 470 All MIE 228 4931100-5907057 MIE 230 5907058-6901029 MIE 255 4924565 - 5907057 MIE 260 5907058 - 6885891 MIE 330 4890180-5889913 MIE 340 5889914-OA3Q7952 Note 1: Refer to top of page 1A-13. NOTICE Refer to appropriate "Stern Drive Service Manual" for Transom Assembly and Stern Drive Unit Repair. (OVER) SERVICE MANUAL OUTLINE SECTION 1 - Important Information/Troubleshooting Part A - General Information Part B - Maintenance Part C - Troubleshooting SECTION 2 - Removal/Installation/Alignment Part A - MCM 120/140/165 Part B - MCM 120R/140R Driveshaft Extension Models Part C - MCM 470/485/488 Part D - MCM 898/228/260 Part E - MCM 898/228/260 Driveshaft Exten sion Models Part F - MCM 330TR/TRS with Mercury Marine Transmission Part G - MCM 330 (B-W) TR/TRS Part H - MCM 370/400TRS and Hi-Performance Engines Part I - MIE 470/228/230/255/260/330/340 SECTION 3 - Electrical System Part A - Starting System Part B - Ignition System Part C - Charging System Part D - Instrumentation Part E - Electrical Kits Part F - Wiring Diagrams SECTION 4 - Fuel System Part A - Fuel Delivery System and Fuel Pumps Part B - Rochester 2 Barrel Part C - MerCarb 2 Barrel Part D - Rochester 4 Barrel Part E - Holley 4 Barrel SECTION 5 - Exhaust System Part A - Exhaust Manifolds/Elbows Part B - Exhaust Risers Part C - Exhaust Collectors SECTION 6 - Engine Part A - G.M. In-Line Part B - Mercury Marine 4 Cylinder Engine PartC-G.M. V-8 SECTION 7 - Cooling System Part A - Seawater Cooled Models Part B - 470/485/488 Part C - Closed Cooled Models SECTION 8 - Drive Systems Part A - Velvet Drive (Borg-Warner) Transmission Part B - Mercury Marine Transmission Part C - Driveshaft Models/Propeller Shaft SECTION 9 - Power Steering System NOTICE Throughout this publication, "Dangers", "Warnings" and "Cautions" (outlined in a border and accompanied by the International HAZARD Symbol ^ ) are used to alert the mechanic to special instructions concerning a particular service or operation that may be hazardous if performed incorrectly or carelessly. OBSERVE THEM CAREFULLY! These "Safety Alerts" alone cannot eliminate the hazards that they signal. Strict compliance to these special instructions when performing the service, plus "common sense" operation, are major accident prevention measures. DANGER — Immediate hazards which WILL result in severe personal injury or death. WARNING — Hazards or unsafe practices which COULD result in severe personal injury or death. CAUTION — Hazards or unsafe practices which could result in minor personal injury or product or property damage. NOTICE TO USERS This service manual has been written and published by the service department of Mercury Marine to aid our dealers' mechanics and company service personnel when servicing the products described herein. It is assumed that these personnel are familiar with the servicing procedures of these products, or like or similar products manufactured and marketed by Mercury Marine. That they have been trained in the recommended servicing procedures of these products which includes the use of mechanics common hand tools and the special Mercury Marine or recommended tools from other suppliers. We could not possibly know of and advise the service trade of all conceivable procedures by which a service might be performed and of the possible hazards and/or results of each method. We have not undertaken any such wide evaluat on. Therefore, anyone who uses a service procedure and/or tool, which is not recommended by the manufacturer, first must completely satisfy himself that neither his nor the product's safety will be endangered by the service procedure selected. All information, illustrations and specifications contained in this manual are based on the latest product information available at time of publication. OF THIS MANUAL It should be kept in mind, while working on the product, that the electrical system and ignition system is capable of violent and damaging short circuits or severe electrical shocks. When performing any work where electrical terminals could possibly be grounded or touched by the mechanic, the battery cables should be disconnected at the battery. Any time the intake or exhaust openings are exposed during service they should be covered to protect against accidental entrance of foreign material which could enter the cylinders and cause extensive internal damage when the engine is started. It is important to note that, during any maintenance procedure, replacement fasteners must have the same measurements and strength as those removed, whether metric or customary. (Numbers on the heads of the metric bolts and on surfaces of metric nuts indicate their strength. Customary bolts use radial lines for this purpose, while most customary nuts do not have strength markings. Mismatched or incorrect fasteners can result in damage or malfunction, or possibly personal injury. Therefore, fasteners removed should be saved for re-use in thesame locations whenever possible. Where the fasteners are not satisfactory for re-use, care should be taken to select a replacement that matches the original. (OVER) REPLACEMENT PARTS WARNING Electrical, ignition and fuel system components on MerCruiser Engines and Stern Drives are designed and manufactured to comply with U.S. Coast Guard Rules and Regulations to minimize risks of fire or explosion. Use of replacement electrical, ignition or fuel system components, which do not comply to these rules and regulations, could result in a fire or explosion hazard and should be avoided. When servicing the electrical, ignition and fuel systems, it is extremely important that all components are properly installed and tightened. If not, any electrical or ignition component opening would permit sparks to ignite fuel vapors from fuel system leaks, if they existed. ENGINE MECHANICAL COMPONENTS Many of the engine mechanical components are designed for marine applications. Unlike automotive engines, marine engines are subjected to extended periods of heavy load and wide-openthrottle operation, therefore, require heavy-duty components. Special marine engine parts have design and manufacturing specifications which are required to provide long life and dependable performance. Marine engine parts also must be able to resist the corrosive action of salt or brackish water that will rust or corrode standard automotive parts within a short period of time. Failure to use recommended Quicksilver service replacement parts can result in poor engine performance and/or durability, rapid corrosion of parts subjectec to salt water and possibly complete failure of the engine. Use of parts other than recommended service replacement parts will void the warranty on those parts which are damaged as a result of the use of other than recommended parts. SECTION 1 - IMPORTANT INFORMATION/ TROUBLESHOOTING PART A - GENERAL INFORMATION INDEX Page Introduction 1A-1 Propeller Information 1A-1 Hi-Performance Boating 1A-1 How to Use This Manual 1A-1 Page Numbering 1A-2 How to Read Parts Manual 1A-2 Directional References 1A-4 Engine Rotation 1A-4 Engine 20-Hour Break-In Period 1A-5 Water Testing New MerCruiser Engines 1 A-5 Serial Number Locations 1A-5 Engine Identification 1A-8 MCM 120R thru 260R Engines and Transom Assemblies Incompatible With Old Models 1A-8 Use of Older Model Stern Drive Units On MCM 120R thru 260R Models 1A-8 Identification of Engines 1A-9 MCM 470TR/230TR/260TR 1A-13 Boat and Engine Performance 1A-13 Boat Bottom 1A-13 Marine Fouling 1A-14 Weight Distribution 1A-14 Water In Boat 1A-14 Propellers 1A-14 Stern Drive Propeller Selection 1A-14 Inboard Propeller Selection 1A-15 Elevation and Climate 1A-15 INTRODUCTION This comprehensive overhaul and repair manual isdesigned as a "Service Guide" for MerCruiser models listed. It provides specific information including procedures for disassembly, assembly, inspection and adjustment, to enable dealers and service mechanics to keep the MerCruiser in top operating condition. The procedures are supplemented with photos and illustrations. Before attempting particular repairs, it is suggested that the repair procedure first be read thru completely to gain a total picture of the repair method, cautions and warnings. PROPELLER INFORMATION For in-depth information on marine propellers and boat per formance -- written by marine engineers -- order "Everything You Should Know About Propellers" Part No. 90-86144. HI-PERFORMANCE BOATING For a booklet entitled Hi-Performance Boat Operation' -- written bv marine engineers - order Part No. 90-86168. HOW TO USE THIS MANUAL The manual is divided into SECTIONS (shown, right) which Section represent major components and systems. 1 Some SECTIONS are further divided into PARTS. Each PART 2 has a title page. An index for the particular PART is printed on 3 the back of the title page. 4 5 SECTIONS and PARTS are listed on the "Service Manual Outline" sheet which immediately follows the cover of this 6 book. 7 8 For Transom Assembly and Stern Drive Unit repair, refer to 9 appropriate "Stern Drive Service Manual". Section Heading General Information/Troubleshooting Removal/lnstallation/Alignment Electrical Systems Fuel Systems Exhaust Systems Engine Cooling Systems Drive Systems Power Steering System 90-95693 485 IMPORTANT INFORMATION/TROUBLESHOOTING - 1A-1 PAGE NUMBERING HOW TO READ PARTS MANUAL i 1A-2 - IMPORTANT INFORMATION/TROUBLESHOOTING 90-95693 485 A. Part Number: For part ordering • Note N.S.S. for Reference N umber 2. PI jg, expansion - that means Not Sold Separately by Mercury Marine, however, in this case, the G.M. Part Number (for the plug) is given in the Description Column. B. Reference Number: For part shown on exploded parts view. C. Description: This is the most important column because it gives: 1) Description of Part: Ref. No. 1 is a Cylinder Block Assembly. No. 9 is a Camshaft, etc. 2) What parts are included with a certain part: Notice how the Description of Part, for Ref. Nos. 1 and 8 thru 14, are at the left side of the column. Description of Part for Ref. Nos. 2 thru 7 are indented under "Cylinder Block Assembly". If Ref. No. 1 (Cylinder Block Assembly) was ordered, all indented parts (Ref. Nos. 2 thru 7) would come with the part. Ref. Nos. 8 thru 14 would not come with Ref. No. 1 arid would have to be ordered separately. If 2 Cylinder Blocks were listed, both cylinder blocks would come with the indented parts. In some cases, an indented part will have another part indented under it. The second indented part will come with the first indented part. 3) Serial number break: If serial number information is listed, check product serial number to ensure that correct part is ordered. 4) Special information: Many times special information will be shown after description such as; LH. Rotation. R.H. Rotation. Filter Up, Filter Down. etc. This will help in selecting the correct part. D. Quantity: Quantity that has to be ordered. E. Special Information Block: Additional information, part numbers for gasket sets. etc. 90-95693 485 IMPORTANT INFORMATION/TROUBLESHOOTING - 1A-11 DIRECTIONAL REFERENCES Front of boat is bow; rear is stern. Starboard side is right side; port side is left side. In this service manual, all directional references are given as they appear when viewing boat from stern, looking toward bow, except on V-Drive inboard engines. (Figure 1) STARBOARD (RIGHT) AFT or STERN (REAR! Figure 1. Directional Reference ENGINE ROTATION Engine rotation terminology at times has caused confusion. To clarify, engine rotation is determined by observing flywheel rotation from the rear (transmission or stern drive end) of the engine looking forward (water pump end). PROPELLER ROTATIONSAME as engine rotation. IS NOT NECESSARILY THE When ordering replacement engines, short blocks or parts for engines, be certain to check engine rotation. Do not rely on propeller rotation in determining engine rotation. a - Left Hand Rotation (CCW) - All MCM Stern Drive Engines, MIE Inboard L.H. 'Standard) Rotation b - Right Hand Rotation (CW) MIE Inboard R.H. (Opposite) Rotation Figure 1. Engine Rotation FORE or BOW (FRONT) 15126 1A-10- IMPORTANT iN FORM ATI ON/TROUBLESHOOTING 90-95693 485 ENGINE 20-HQUR BREAK-IN PERIOD IMPORTANT: Proper break-in is essential to obtain-mal reading occurs, stop engine immediately and determine ing minimum oil consumption, maximum engine cause. performance and service. 7. FREQUENTLY CHECK crankcase oil level and add oil if necessary. It is normal for oil consumption to be somewhat The first 20 hours of operation is the engine (new or rebuilt) high during the break-in period. break-in period. During this period, it is extremely important 8. At end of 20-hour break-in period, drain break-in oil from that the engine is operated, as outlined in the following infor-crankcase and replace oil filter. Fill crankcase with correct mation. grade and viscosity oil. 1. DO NOT operate engine below 1500 RPM for extended periods of time during the first 10 hours. During this WATER TESTING NEW MERCRUISER ENGINES period, shift into gear as soon as possible after starling engine and advance throttle so that RPM is above 1500 Care must be exercised during the first 20 hours of operation (provided that conditions permit safe operation at this on new MerCruisers or possible engine failure may occur. If a speed). new engine has to be water-tested at full throttle before the 2. DO NOT operate at any one constant speed for extended break-in period is complete, follow this procedure. periods of time. 3. DO NOT exceed 3A of full throttle during the first 10 hours 1. Start engine and run at idle RPM until normal operating of operation. During the next 10 hours, occasional opera-temperature is reached. tion at full throttle (5 minutes at-a-time maximum) is 2. Run boat up on plane. permissible. 3. Advance engine RPM (in 200 RPM increments) until en4. AVOID full throttle acceleration from stopped position. gine reaches its maximum rated RPM. 5. DO NOT operate at full throttle until engine reaches normal operating temperature. IMPORTANT: DO NOT run at maximum RPM for 6. OBSERVE INSTRUMENTATION carefully. If an abnor-more than 2 minutes. SERIAL NUMBER LOCATIONS a - Serial Number Plate b - Starter Motor Figure 1. MCM 120/120R/140/140R/165 90-95693 485 16263 a - Serial Number Plate b - Front of Heat Exchanger Figure 2. MCM 470/485 and Early MCM 470R/488R IMPORTANT INFORMATION/TROUBLESHOOTING - 1A-11 a - Serial Number Plate b - Starboard Side of Flywheel Bell Housing and Cylinder Block a - Serial Number Plate Figures. MCM 330 (B-W) b - Fuel Pump Figure 3. Later MCM 470R/488R Figure 4. MCM 898/898R/228/228R/260/260R/330 16727 a - Serial Number Plate b - Starter Motor a - Serial Number Plate b - Flywheel Bell Housing Figure 6. MCM 370/400/400 Cyclone/440 Cyclone/ 460 Cyclone/475 Turbo and MCM 470TR/ 230TR/260TR 90-95693 485 1A-10- IMPORTANT iN FORM ATI ON/TROUBLESHOOTING a - Serial Number Plate b - Starter Motor a - Serial Number Plate b - Starter Motor - Serial Number Plate Figure 9. MIE 230/260/340 - Front of Heat Exchanger Figure 7. MIE 470 a - Serial Number Plate b - Starter Motor Figure 8. MIE 228/255/330 90-95693 485 IMPORTANT INFORMATION/TROUBLESHOOTING - 1A-7 ENGINE IDENTIFICATION MCM 120R-thru-260R ENGINES and TRANSOM ASSEMBLIES INCOMPATIBLE WITH OLD MODELS The MCM 120R-thru-260R engines and transom assemblies cannot be used to replace previous (older) MCM 120-thru-260 engines and transom assemblies for the following reasons: • Engine mounting hole center-to-center dimension is different in flywheel housing and inner transom plate. MCM 120R-thru-260R -9-1/2" (241mm) MCM 120-thru-485 - 14-1/2" (368mm) MCM 898-thru-260 - 12-1/2" (318mm) • Exhaust collector systems are not interchangeable between the "R " models and the previous models. USE OF OLDER MODEL STERN DRIVE UNITS ON MCM 120R-thru-260R MODELS Mercury Marine does not recommend the use of older model stern drive units on the new models, as the units will not mate up satisfactorilv with the transom assemblv. In addition, the older in-line model stern drive units are equipped with universal joint coupli ng end yoke (39385A1). (Figure 1) This yoke is shorter than voke (59830A1) (Figure 2) used on the new model stern drive units, and therefore, will not fully engage the engine coupler splines. IMPORTANT: Use of an older in-line model stern drive unit on a new model will result in a spline failure to coupling and/or yoke. Figurel. Universal Joint Coupling End Yoke (39385A1) Used On Older In-Line Models Figure 2. Universal Joint Coupling End Yoke (59830A1) Used On MerCruiser MC M 120R-thru-260R Models and Older V-8 Models 1A-10- IMPORTANT iN FORM ATI ON/TROUBLESHOOTING 90-95693 485 IDENTIFICATION OF ENGINES a - Shift Plate On Inner Transom Plate b - Straight-Back Exhaust Elbow Figure 3. MCM 120/140 a - Shift Plate Mounted On Inner Transom Plate b - Separate Coolant Reservoir and Exhaust Elbow c - 3' (76mm) Heat Exchanger Figure 6. MCM 470 15871 a - Shift Plate On Side of Exhaust Manifold b - Off-Set Exhaust Elbow Figure 4. MCM 120R/140R a - Shift Plate On Side of Exhaust Man fold b - Combined Coolant Reservoir and Exhaust Elbow c - 4" (102mm) Heat Exchanger Figure 7. MCM 470R 10920 Figure 5. MCM 165 a - Shift Plate Mounted on Inner Transom Plate b-C o mbined Coolant Reservoir and Exhaust Elbow c - 3" i'76mm) Heat Exchanger Figure 8. MCM 485 90-95693 485 IMPORTANT INFORMATION/TROUBLESHOOTING - 1A-11 a - Shift Plate Mounted on Side of Exhaust Manifold b - Combined Coolant Reservoir and Exhaust Elbow a - Exhaust Elbow Mounted On Aft End of Manifold c - 4" (102mm) Heat Exchanger b - Mercury Marine Transmission d - 4 Barrel Rochester Carburetor Figure 12. MCM 330 Figure 9. MCM 488R a - Exhaust Elbow Mounted In Center of Manifold b - Thunderbolt IV (HEI) Ignition System c - Borg-Warner Transmission b - Shift Plate At Back of Engine Figure 13. MCM 330 (B-W) c - Conventional Ignition System Figure 10. MCM 898/228/260 a - Exhaust Elbow Mounted On Aft End of Manifold a - Exhaust Elbow Mounted In Center of Manifold b - Shift Plate On Side of Exhaust Elbow c - Thunderbolt IV (HEI) Ignition System Figure 11. MCM 898R/228R/260R 1A-10- IMPORTANT iN FORM ATI ON/TROUBLESHOOTING 90-95693 485 a - Rocker Arm Cover Decal - "370" or "Series 400" b - Serial Number Plate on Flywheel Housing - "370" Stamped in Plate 18733 Figure 14. MCM 370/400 a - Rocker Arm Cover Decal - "440" b - Serial Number Plate on Flywheel Housing - "440" Stamped in Plate c - Early Models Had Rochester 4 Barrel Carburetor, Later Models Had Holley 4 Barrel Carburetor d - Center Outlet Type Exhaust Manifold Figure 16. MCM 440 Cyclone 18731 a - Rocker Arm Cover Decal - "400" b - Serial Number Plate on Flywheel Housing - "400" Stamped in Plate c - Rochester 4 Barrel Carburetor d - 370 Type Exhaust Manifold and Elbow Figure 15. MCM 400 Cyclone 18732 a - Rocker Arm Cover Decal - "460" b - Seriai Number Plate on Flywheel Housing - "460" Stamped in Plate c - Holley 4 Barrel Carburetor d - Center Outlet Type Exhaust Manifold Figure 17. MCM 460 Cyclone 90-95693 485 IMPORTANT INFORMATION/TROUBLESHOOTING - 1A-11 18730 11274A a - Rocker Arm Cover Decal - "475" b - Serial Number Plate on Flywheel Housing - "475" Stamped a - Exhaust Elbow Mounted or. Aft End of Manifold in Plate b - Conventional Ignition System c - 370 Type Exhaust Manifold with Turbo Figure 20. MIE 228/255/330 Inboard Figure 18. MCM 475 Turbo 15018 Figure 19. MIE 470 Inboard a - Exhaust Elbow Mounted In Center of Manifold b - Thunderbolt IV (HEI) Ignition System Figure 21. MIE 230/260/340 Inboard 90-95693 485 1A-10- IMPORTANT iN FORM ATI ON/TROUBLESHOOTING MCM 470TR/230TR/260TR Limited production. Repair and specifications for engine is the same as MIE 470. Mercury Marine Hi-Performance Products has built three TR Production Performance Power Packages. "Removal, Installa-MCM 230TR: MIE 230 (L.H.) inboard engine with a Borgtion and Alignment" are similar to the MCM 330 (B-W) in Warner transmission (for TR package) added to engine. Repair "Section 2. Part G". For transmission and tailstock repair, and specifications for engine is the same as MIE 230. refer to "Section 8, Part A". MCM 260TR: MIE 260 (L.H.) inboard engine with a Borg- MCM 470TR: MIE 470 (L.H.) inboard engine with a Borg-U arner transmission (for TR package) added to engine. Repair Warner transmission (for TR package) added to engine. and specifications for engine is the same as MIE 260. BOAT and ENGINE PERFORMANCE NOTICE For further information, order "Everything You Need To Know About Propellers" (P/N 9086144) from: Mercury Marine Attn: Publications Department 1939 Pioneer Road Fond du Lac, Wl 54935 U.S.A. Figure 1 BOAT BOTTOM For maximum speed,a boat bottom should be as flat as possible in a fore-aft direction (longitudinally) for approximately the last 5 ft. (1.5m) (Figure 1). For best speedand minimum spray the corner between the bottom and the transom should be sharp. The bottom is referred to as having a "hook" if it is concave in the fore-and-aft direction (Figure 2). A "hook" causes more lift on the bottom near the transom and forces the bow to drop. This increases wetted surface and reduces boat speed, but it helps planing and reduces any porpoising (rythmical bouncing) tendency. A slight hook" is often built in by the manufacturer. A "hook" can also be caused by not trailering or storing the boat with support directly under the transom. A "rocker" is the reverse of a "hook" (Figure 3). The bottom is convex or bulged in the fore-and-aft direction. It can cause the boat to porpoise. Any "hook", "rocker or surface roughness on the bottom. particularly in the all-important center-aft portion (Figure 4), will have a negative effect on speed, often several miles per hour on a fast boat. Figure 2 Rocker Figure 3 Figure 4 90-95693 485 IMPORTANT INFORMATION/TROUBLESHOOTING - 1A-11 Marine Fouling Water in Boat Fouling is a kind of unwanted buildup (usually animalvegetable- derived) occurring on the boat's bottom and drive unit. Fouling adds up to drag, which reduces boat performance. In fresh water, fouling results from dirt, vegetable matter, algae or slime, chemicals, minerals and other pollutants. In salt water, barnacles, mossand other marine growth often produce dramatic buildup of material quickly. So it's important to keep the hull as clean as possible in all water conditions to maximize boat performance. Special hull treatments, such as antifouling paint, will reduce the rate of bottom fouling. However, due to the fact that drive units (outboard or stern drive) are made primarily of aluminum, be sure to select an antifouling paint having a copper- free. organo-tin base. The BIS (Tri-Butyl-Tin) Adipate (TBTA) base paint will not set up a galvanic corrosion "cell" as it is completely compatible with aluminum and avoids any electrolysis problems connected with many other paints. Applied according to instruction, it is also very effective. WEIGHT DISTRIBUTION Weight distribution is extremely important; it affects a boat's running angle or attitude. For best top speed, all movable weight — gear and passengers — should be as far aft as possible, to allow the bow to come up to a more efficient angle (3° to 5°). But on the negative side of this approach is the problem that, as weight is moved aft, some boats will begin an unacceptable porpoise. Secondly, as weight is moved aft, getting on plane becomes more difficult. Finally, the ride in choppy water becomes more uncomfortable as the weight goes aft. With these factors in mind, each boater should seek out what weight locations best suit his needs. Weight and passenger loading placed well forward increases the "wetted area" of the boat bottom and, in some cases, virtually destroys the good performance and handling characteristics of the boat. Operation in this configuration can produce an extremely wet ride, from wind-blown spray,and could even be unsafe in certain weather conditions or where bow- steering may occur. W eight distribution is not confined strictly to fore and aft locations, but also applies to lateral weight distribution. Uneven weight concentration to port or starboard of the longitudinal centerline can produce a severe listing attitude that can adversely affect the boat's performance, handling ability and riding comfort. In extreme rough water conditions, the safety of the boat and passengers may be in jeopardy. W hen a boat has lost performance, the bilge should be checked for water. Water weighs approximately 8 lbs. (29kg) per 1 gal. (3.8 litres) and can add considerable weight to a boat, therebv causing a loss of performance. Because hulls are constructed with stringers and cross members, each separate area can hold water. Most boat manufactures have drain holes to drain out the water. Make sure these drain holes are open. PROPELLERS Pitch is the distance that a propeller would move in one revolution (if it were traveling through a soft solid - like a screw in wood). Diameter is the distance across the circle made by the blade tips as the propeller rotates. When a propel.er is identified as 13x21. it has a 13" diameter with 21" of pitch. Theoretically, the propeller would move forward 21" in one revolution. Stern Drive Propeller Selection If a propeller is installed that does not allow engine RPM to reach the specified full-throttle RPM range, the engine will "labor" and will not produce full power. Operation under this condition will cause excessive fuel consumption, engine overheating and possible piston damage (due to detonation). On the other hand, installation of a propeller, that allows engine to run above the specified RPM limit, will cause excessive wear on internal engine parts which will lead to premature engine failure. Quicksilver propeller, for stern drives, cannot be bought in different diameters for a certain pitch, material and style. Example; a 19" pitch aluminum Black Max propeller comes only with a 14" diameter. It is the responsibility of the boat manufacturer and/or selling dealer to equip stern drive unit with the correct propeller. The correct propeller will allow the engine to operate within the specified RPM range at wide-open-throttle (WOT). Correct propeller must be used to obtain maximum engine performance and efficiency. 1A-10- IMPORTANT iN FORM ATI ON/TROUBLESHOOTING 90-95693 485 Because of many variables of boat design, only testing will determine the best propeller for a particular application. To test if the correct propeller has been installed, operate boat (with average load onboard) at WOT and check RPM with an accurate tachometer. Engine RPM should be near top of the specified range so that, under a heavv load, engine speed will not fall below specifications. If engine speed is too high, replace propeller with one that hasa higher pitch. Ifer.gine speed is too low. replace with a lower pitch propeller. Normally, a 300 to 400 RPM change exists between propeller pitches. Inboard Propeller Selection Inboard propellers are made in many different styles. Unlike stern drive propellers, inboard propellers can be bought in different diameters for a certain pitch, material and style. They also come with or without a cup. Changing diameter, pitch or cupping will have an effect on engine speed and prop slip, and in turn, directly effect the performance of a boa:. The blade configuration of a propeller is also important. Two 11" x 12" propellers from different propeller manufacturers may perform quite differently. It is the responsibility of the boat manufacturer and/or selling dealer to equip the boat with the correct propeller. The correct propeller will allow the engine to operate within the specified RPM range at wide-open-throttle (WOT). Correct propeller must be used to obtain maximum engine performance and efficiency. Because of many variables of boat design, onlv testing will determine the best propeller for a particular application. To test if the correct propeller has been installed, operate boat (with average load onboard) at OTand check RPM with an accurate tachometer. Engine RPM should be near top of the specified range so that, under a heavy load, engine speed will not fall below specifications. If the engine exceeds the recommended RPM. an increase in pitch and/or diameter is required. A decrease in pitch and/or diameter is called for if engine RPM is too low. Normally a 1" change in pitch or diameter will change engine speed by ISO RPM. Cupping a propeller usually will reduce engine RPM by approximately 200 RPM. ELEVATION and CLIMATE Elevation has a very noticeable effect on the wide-openthrottle power ofan engine. Sinceair (containingoxygen) gets thinner as elevation increases, the engine begins to starve for air, like usinga supercharger in reverse. Humidity,barometric pressure and temperature do have a noticeable effect on the density of air. Heat and humidity thin the air. This phenomenon can become particularly annoying when an engine is propped out on a cool, dry day in spring and later, on a hot, sultry day in August, doesn't have its old zip. (See HP/weather relationship chart, Figure 5.) Although some performance can be regained by dropping to a lower-pitch propeller, the basic problem still exists. The propeller is too large in diameter for the reduced power output. The experienced marine dealer or a Quicksilver Propeller Repair Station can determine how much diameter to remove from a lower-pitch propeller for specific high-elevation locations. In some cases, a gear-ratio change (to stern drive unit) to more reduction is possible and very beneficial. It is a known fact that weather conditions exert a profound effect on power output of internal combustion engines. Therefore, established horsepower ratings refer to the power that the engine will produceat its rated RPM undera specific combination of weather conditions. Figure 5. 90-95693 485 IMPORTANT INFORMATION/TROUBLESHOOTING - 1A-11 INDEX MCM 120-260 Maintenance ScheduleMCM 470TR/230TR/260TR and MCM 330 475 Turbo Maintenance ScheduleMIE 470-340 Maintenance ScheduleTune-Up Chart (MCM 120-165) Tune-Up Chart (MCM 470-488R) Tune-Up Chart (MCM 898-260) Tune-Up Chart (MCM 898R-260R) Tune-Up Chart (MCM 330-370/400) Tune-Up Chart (MCM 400 Cyclone 475 Turbo) Page 1B-2 1B-4 1B-6 1B-8 1B-9 1B-10 1B-11 1B-12 1B-13 Tune-Up Chart (MCM 470TR/230TR/260TR) ...............1B-14 Tune-Up Chart (MIE 470) 1B-15 Tune-Up Chart (MIE 228/255/330) 1B-16 Tune-Up Chart (MIE 230/260/340) 1B-17 Capacity Charts 1B-18 Fuel, Oil, Fluid and Coolant Specifications.................. 1B-22 Fuel No Lead Gasoline/Alcohol BlendsCrankcase OilPower SteeringTransmissionCoolant Maintaining Crankcase Oil LevelOver-Filling Engine CrankcaseChecking Level/Filling Changing Oil and FilterMaintaining Power Steering Fluid Level 1B-22 1B-22 1B-23 1B-24 1B-24 1B-24 1B-25 1B-25 1B-25 1B-26 1B-27 Page Filling and Bleeding System 1B-28 Maintaining Transmission Fluid Level 1B-29 Borg-Warner Transmission 1B-29 Mercury Marine Transmission 1B-29 Maintaining Coolant Level 1B-30 Flushing Cooling System 1B-30 Lubrication 1B-32 Throttle Cable 1B-32 Shift Cable 1B-32 Engine Coupling "U"-Joint Splines (MCM 120-260) 1B-33 "U"-Joint Shaft Splines (Stern Drive Models with Borg-Warner Transmission) 1B-34 Output Housing (Stern Drive Models with Mercury Marine Transmission) 1B-34 Driveshaft Extension Models (MCM 120R/140R and 898/228/260) 1B-34 Staggered Engine (MCM 370-475 Turbo) ............... 1B-35 Starter Motor [MCM 330 (B-W) and MIE 230/260/340 Only] 1B-35 MCM 470TR/230TR/260TR 1B-35 Steering System/Stern Drive 1B-35 Compression Test Out-of-Season StoragePrecautionsLayupRecommissioning 1B-36 1B-36 1B-36 1B-37 1B-38 NOTICE Refer to appropriate "Stern Drive Service Manual" for all transom plate and stern drive maintenance. 90-95693 485 IMPORTANT INFORMATION/TROUBLESHOOTING- 1A-11 MCM 120-260 MAINTENANCE SCHEDULE • = To Be Performed by Owner I = To Be Performed by an Authorized MerCruiser Dealer NOTE: Refer to the end of this chart for explanation of lettered references (A, B, etc.) and "NOTES". Location and Service When Starting Engine Each Day After First 20 Hours of Operation Every 50 Hours of Operation Every 100 Hours of Operation At Least Once Each Year Engine Crankcase Oil - Check level • Closed Cooling Models Only - Check coolant level • Remote Control and Steering System Check for proper operation • • Power Package (Entire) Observe for obvious leaks (water, fuel, oil. exhaust, etc.) • Ignition System - Check timing and adjust, if necessary • • • Crankcase Oil and Oil Filter - Change • Refer to Page 1B-23 • Power Steering Models Only - Check fluid level (A) • • • Power Package (Entire) - Carefully inspect for leaks (water, coolant, fuel, oil, fluid and exhaust) • • • Cooling System Hose Clamps - Check tightness; clean and test pressure cap • • Note 1 • Engine Exhaust Bellows Clamps - Check tightness • • Note 1 • Drive Belts (All) - Inspect condition and check tension. • • • Ignition System - Clean and inspect condition • • Note 1 • Power Package (Entire) - Check for loose, missing or damaged parts, (especially engine and drive unit mount fasteners and starter, and Power Steering pump mounting fasteners). • • • Steering System - Lubricate and inspect (Refer to "Stern Drive Service Manual") • Note 2 • Battery - Check electrolyte level and specific gravity. Inspect case for damage. • • Electrical System (Entire) - Check loose or dirty connections or damaged wiring (especially battery cables). • Note 2 • Fuel Pump Sight Tube (or Glass) - Check for ev dence of fuel (indicating a ruptured diaphragm) • • Hoses (All) - Inspect for cracks, swelling, weather checking or other signs of deterioration. Check connections for adequate tightness. • • Engine Exhaust Bellows - Inspect for cracks, swelling, burns or other signs of deterioration. • • Flame Arrestor and Crankcase Ventilation Hose - Clean and Inspect. • • 1A-10- IMPORTANT iN FORM ATI ON/TROUBLESHOOTING 90-95693 485 Location and Service When Starting Engine Each Day After First 20 Hours of Operation Every 50 Hours of Operation Every 100 Hours of Operation At Least Once Each Year Shift and Throttle Cable and Linkage Lubricate and inspect. (B) • Note 2 • Engine Coupling and Stern Drive Unit Universal Joint Shaft Splines and Cross Bearings - Lubricate (C) • • Engine Alignment - Check • • Driveshaft Extension Models Only - Lubricate (C) • • Fuel Filters - Replace • Power Package Exterior Surfaces - Clean and paint. (D) (E) • Note 3 Seawater Pickup Pump - Disassemble and inspect. • Closed Cooling Models Only - Test coolant for alkalinity. • Closed Cooling Models Only - Clean heat exchanger seawater section • Transom Assembly and Stern Drive Unit Refer to "Stern Drive Service Manual". Cooling System - Flush seawater section (CORROSIVE AREAS ONLY) After Use Each Day Power Package Exterior Surfaces - Spray with rust preventative. Fresh Water Areas - Every 6 Weeks Salt Water Areas - Every 2-3 Weeks Closed Cooling Models Only - Replace coolant (F) Every 2 Years Seawater Pickups Check for marine growth or debris Every 30 Days NOTE 4 Boat Bottom - Clean and paint As Required Carburetor - Adjust • As Required (A) Use Automatic Transmission Fluid (ATF). Dexron or Dexron II. (B) Use SAE 30W engine oil. (C) Use Quicksilver 2-4-C Multi-Lube. (D) Use Quicksilver Primer and Spray Paint. (E) Use Quicksilver Corrosion and Rust Preventive Type II. (F) Use a 50/50 mixture of ethylene glycol anti-freeze that meets GM specification 1825M and pure soft water. Refer to page 1B-24. (1) In fresh water areas, every 100 hours of operation or 120 days (whichever comes first). In saltwater areas, every 50 hours of operation or 60 days (whichever comes first). (2) In fresh water areas, every 50 hours of operation or 60 days (whichever comes first). In saltwater areas, every 25 hours of operation or 30 days (whichver comes first). (3) Requires more frequent attention, if used in extremely salty, polluted or mineral laden waters. (4) Reouires more frequent attention, if used in areas with rapid marine growth. 90-95693 485 IMPORTANT INFORMATION/TROUBLESHOOTING - 1A-11 MCM 470TR/230TR/260TR and MCM 330-475 Turbo Maintenance Schedule Location and Service When Starting Engine Each Day After First 20 Hours of Operation Every 50 Hours of Operation Every 100 Hours of Operation At Least Once Each Year Engine Crankcase Oil - Check level • Closed Cooling Models Only - Check coolant level • Remote Control and Steering System Check for proper operation • Power Package ;Entire) Observe for obvious leaks (water, fuel, oil, exhaust, etc.) • Transmission Fluid - Check level (A) • Ignition System - Check timing and adjust, if necessary • • • Crankcase Oil and Oil Filter - Change • Refer to Page 1B-23 • Power Steering Models Only - Check fluid level (B) • • • Cooling System Hose Clamps - Check tightness. • • Note 1 • Exhaust Hose Clamps - Check tightness • • Note 1 • Drive Belts (All) Inspect condition and check tension. • • • Ignition System - Clean and inspect condition • • Note 1 • Power Package (Entire) Carefully inspect for leaks (water, coolant, fuel, oil, fluid and exhaust) • • • Power Package (Entire) Check for loose, missing or damaged parts, (especially engine and drive unit mount fasteners and starter, and Power Steering pump mounting fasteners). • • • Steering System Lubricate and inspect (Refer to "Stern Drive Service Manual") • Note 2 • Battery Check electrolyte level. Inspect case for damage. • • Electrical System (Entire) Check loose or dirty connections or damaged wiring (especially battery cables). • Note 2 • Fuel Pump Sight Tube (or Glass) Check for evidence of fuel (indicating a ruptured diaphragm). • • Hoses (All) Inspect for cracks, swelling, weather checking or other signs of deterioration. Check connections for adequate tightness. • • Engine Exhaust Hoses - Inspect for cracks, swelling, burns or other signs of deterioration. • • 1A-10- IMPORTANT iN FORM ATI ON/TROUBLESHOOTING 90-95693 485 Flame Arrestor and Crankcase Ventilation Hose - Clean and Inspect. • • Shift and Throttle Cable and Linkage Lubricate and inspect. (C) • Note 2 • MCM 230/260/330 (B-W) Only Lubricate Starter Motor (D) • Note 1 • Stern Drive Unit Universal Joint Shaft Splines and Cross 3earings - Lubricate (E) • • Drive Shaft and Tailstock Input Bearing, Lubricate (Staggered Installations Only) (E) • • Tailstock Output Bearing, Lubricate (Staggered Installations Only) (E) • • Engine Alignment Check • • Fuel Filters Replace • Transmission Fluid Replace and clean strainer. (A) • Note 3 Power Package Exterior Surfaces Clean and paint. (F) • Note 4 Seawater Pickup Pump Disassemble and inspect. • Steering Head and Remote Control Inspect and lubricate. (E) • Closed Cooling Models Only Test coolant for alkalinity. • Closed Coding Models Only - Clean heat exchanger seawater section • Transom Assembly and Stern Drive Unit Refer to ' Stern Drive Service Manual". Cooling System Flush seawater section (CORROSIVE AREAS ONLY) After Use Each Day Power Package Exterior Surfaces Spray with rust preventative. (G) Fresh Water Areas Every 6 Weeks Salt Water Areas Every 2-3 Weeks Closed Cooling Models Only - Replace coolant (H) Every 2 Years Seawater Pickups Check for marine growth or debris Every 30 Days NOTE 5 Boat Bottom Clean and paint As Required Carburetor Adjust • As Required (A) Use Automatic Transmission Fluid (ATF), Type F, Dexron or Dexron II. (B) Use Automatic Transmission Fluid (ATF). Dexron or Dexron II. (C) Use SAE 30W engine oil. (D) Use Lubrip ate Extra-Heavy Gear Shield or its equivalent. (E) Use Quicksilver 2-4-C Multi-Lube. (F) Use Quicksilver Primer and Spray Paint. (G) Use Quicksilver Corrosion and Rust Preventive Type 11. (H) Use a 50/50 mixture of ethylene glycol anti-freeze that meets GM specification 1825M and pure, soft water. Refer to page 1B-24. (1) In fresh water areas, every 100 hours of operation or 120 days (whichever comes first). In saltwater areas, every 50 hours of operation or 60 days (whichever comes first). (2) In fresh water areas, every 50 hours of operation or 60 days (whichever comes first). I n saltwater areas, every 25 hours of operation or 30 days (whichever comes first). (3) Requires more frequent attention, if used for high speed or heavy-duty operation. (4) Requires more frequent attention, if used in extremely salty, polluted or mineral-laden waters. (5) Requires more frequent attention, if used in areas with rapid marine growth. 90-95693 485 IMPORTANT INFORMATION/TROUBLESHOOTING - 1A-11 MIE 470-340 MAINTENANCE SCHEDULE • = To Be Performed by Owner • = To Be Performed by an Authorized MerCruiser Dealer NOTE: Refer to the end of this chart for explanation of lettered references (A, B, etc.) and "NOTES". Location and Service When Starting Engine Each Day After First 20 Hours of Operation Every 50 Hours of Operation Every 100 Hours of Operation At Least Once Each Year Closed Cooling Models Only - Check coolant level. • Engine Crankcase Oil - Check level • Power Package (Entire) - Observe for obvious leaks (water, fuel, oil, exhaust, etc.) • Remote Contro and Steering System Check for proper operation • Transmission Fluid - Check level (A) • Cooling System Hose Clamps - Check tightness. • • Note 1 • Drive Belts (All) Inspect condition and check tension. • • • Exhaust System Inspect condition. Check hose clamps for adequate tightness. • • Note 1 • Ignition System - Clean and inspect condition • • Note 1 • Power Package (Entire) Check for loose, missing or damaged parts, (especially engine mount fasteners and starter, and alternator mounting fasteners). • • • Crankcase Oil and Oil Filter - Change • Refer to Page 1B-23 • Engine Alignment - Check • • Ignition System - Check timing and adjust, if necessary. • • Battery - Check electrolyte level and specific gravity. Inspect case for damage. • • Electrical System (Entire) Check loose or dirty connections or damaged wiring (especially battery cables). • Note 2 • Fuel Pump Sight Tube (or Glass) - Check for evidence of fuel. • • Flame Arrestor and Crankcase Ventilation Hoses - Clean and inspect • • Hoses (All) - Inspect for cracks, swelling, weather checking or other signs of deterioration. Check connections for adequate tightness. • • 1A-10- IMPORTANT iN FORM ATI ON/TROUBLESHOOTING 90-95693 485 Shift and Throttle Cable and Linkage Lubricate and inspect. (B) • Note 1 • MIE 230/260/340 Only Lubricate starter motor (C) • Note 1 • Fuel Filters Replace • Power Package Exterior Surfaces Clean and paint. (D) • Note 3 Seawater Pickup Pump Disassemble and inspect. • Closed Cooling Models Only - Clean seawater section of heat exchanger • Note 3 Steering Head and Remote Control Inspect and lubricate. (E) • Transmission Fluid Change. (A) • Note 4 Boat Bottom Clean and paint As Required Carburetor Adjust • As Required Closed Cooling Models Only - Clean closed cooling section As Required Closed Cooling Models Only Change coolant At Least Once Every 2 Years Closed Cooling Models Only Check coolant for alkalinity At Least Once Between Change Intervals Power Package Exterior Surfaces Spray with rust preventive. (F) Fresh Water Areas Every 6 Weeks Salt Water Areas Every 2-3 Weeks Propeller. Shaft and Strut Inspect for damage and tighten gland nut (if applicable). Refer to Boat Manufacturer's Recommendations. Sea Strainer (if so eqiupped) Clean Refer to Manufacturer's Recommendations. Seawater Cooling System Flush (CORROSIVE AREAS ONLY) After Use Each Day Seawater Pickup Check for marine growth or debris Every 30 Days Note 5 Steering System (Entire) Check for loose, missing or damaged parts. Refer to Boat Manufacturer's Recommendations. (A) Use Automatic Transmission Fluid (ATF), Type F, Dexron or Dexron II. (B) Use SAE 30 engine oil. (C) Use Lubriplate Extra-Heavy Gear Shield or its equivalent. (D) Use Quicksilver Primer and Spray Paint. (E) Use Quicksilver 2-4-C Multi-Lube. (F) Use Qu cksilver Corrosion and Rust Preventive Type II. l: (1) In fresh water areas, every 100 hours of operation or 120 days (whichever comes first). In saltwater areas, every 50 hours of operation or 60 days (whichever comes first). (2) In fresh water areas, every 50 hours of operation or 60 days (whichever comes first). In saltwater areas, every 25 hours of operation or 30 days (whichever comes first). (3) Requires more frequent attention, if used in extremely salty, polluted or mineral-laden waters. (4) Requires more frequent attention, if used for high speed or heavy-duty operation. (5) Requires more frequent attention, if used in areas with rapid marine growth. 90-95693 485 IMPORTANT INFORMATION/TROUBLESHOOTING - 1A-11 TUNE-UP CHART MODEL MCM 120/120R MCM 140/140R MCM 165 Horsepower (Kilowatts) 120 (90) 140 (104) 165 (123) Number of Cylinders 4 6 Displacement 153 CID (2.5 litre) 181 CID (3 litre) 250 CID (4 litre) Bore/Stroke 3.87"/3.25" (98.3/82.6mm) 4.00"/3.60" (101.7/91.4mm) 3.87"/3.53" (98.3/89.7mm) Compression Ratio 8.5:1 8.0:1 Compression Pressure 140 PSI (966 kPa) Idle RPM (In Forward Gear) 650-700 Max. RPM (At W.O.T.) 3900-4300 4200-4600 3900-4300 Oil PSI (At 2000 RPM) 30-60 PSI (207-414 kPa) Min. Oil PSI (At Idle) 4 PSI (28 kPa) Fuel Pump PSI (At 1000 RPM) 5-6-1/2 PSI (35 - 44 kPa) Electrical System 12 Volt Negative (-) Ground Min. Battery Cold Cranking Amps 305 375 Firing Order 1-3-4-2 1-5-3-6-2-4 Spark Plug Type AC-MR43T Champion RV8C Autolite-144 NKG-BR6FS Spark Plug Gap .035" (,9mm) Breaker Point Gap .022" (.5mm) .016"-.019" (.4-.45mm) Dwell 28° - 34° Breaker Point Spring Tension 19-23 Oz. (540-65Cg) Timing (At Idle RPM) 8° BTDC 6° BTDC 8° BTDC Preliminary Idle Mixture 1-1/4 Turns Thermostat 143° F (62° C) 1 B-12- IMPORTANT INFORMATION/TROUBLESHOOTING 90-95693 1-888 TUNE-UP CHART MODEL MCM 470 MCM 470R MCM 485 MCM 488R Horsepower (Kilowatts) 170 (127) 185 (131) 188 (140) Number of Cylinders 4 Displacement 224 CID (3.7 litre) Bore/Stroke 4.36"/3.75" (110.7/95.3mm) Compression Ratio 8.8:1 Compression Pressure 150 PSI (1035 kPa) Idle RPM (In Forward Gear) 650-700 Max. RPM (At W.O.T.) 3800-4200 4400-4800 Oil PSI (At 2000 RPM) 30-60 PSI (207-414 kPa) Min. Oil PSI (At Idle) 4 PSI (28 kPa) Fuel Pump PSI (At 1000 RPM) 5 - 6-1/2 PSI (35-44 kPa) Electrical System 12 Volt Negative (-) Ground Min. Battery Cold Cranking Amps 450 Firing Order 1-3-4-2 Spark Plug Type AC-R42TS Champion - RV9YC Autolite-13 NGK-BPR6FS Spark Plug Gap .035" (,9mm) Breaker Point Gap .022" (.5mm) Dwell 28° -34° Breaker Point Spring Tension 19-23 Oz. (5^0-650g) Timing (At Idle RPM) 8C BTDC Preliminary Idle Mixture 1-1/4 Turns Thermostat 160°F (71 °C) 90-95693 1-888 IMPORTANT INFORMATION/TROUBLESHOOTING - 1B-35 TUNE-UP CHART MODEL MCM 898 MCM 228 MCM 260 Horsepower (Kilowatts) 198 (148) 228 (170) 260 (194) Number of Cylinders V-8 Displacement 305 CID (5 litre) 350 CID (5.7 litre) Bore/Stroke 3.74"/3.48" (95/88.4mm) 4.00"/3.48" (101.6/88.4mm) Compression Ratio 8.5:1 Compression Pressure 150 PSI (1035 kPa) 155 PSI (1069 kPa) 150 PSI (1035 kPa) Idle RPM (In Forward Gear) 650-700 Max. RPM (At W.O.T.) 3800-4200 4200-4600 Oil PSI (At 2000 RPM) 30-55 PSI (207-379 kPa) Min. Oil PSI (At Idle) 4 PSI (28 kPa) Fuel Pump PSI (At 1800 RPM) 5-1/4 6- 1/2 PSI (36 - 44 kPa) Electrical System 12 Volt Negative (-) Ground Min. Battery Cold Cranking Amps 305 350 Firing Order 1-8-4-3-6-5-7-2 Spark Plug Type AC-MR43T Champion RV8C Autolite-144 NGK-BR6FS Spark Plug Gap .035" (,9mm) Breaker Point Gap .016"-.019" (.4-.45mm) Dwell 26° - 31° Breaker Point Spring Tension 25-30 Oz. (709-850g) Timing (At Idle RPM) 8° BTDC Preliminary Idle Mixture 1-1/4 Turns 2-3 Turns Thermostat 143°F (62°C) 1 B-10 - IMPORTANT INFORMATION/TROUBLESHOOTING 90-95693 1-888 TUNE-UP CHART MODEL MCM 898R MCM 228R MCM 260R Horsepower (Kilowatts) 198 (148) 228 (170) 260 (194) Njmber of Cylinders V-8 Displacement 305 CID (5 litre) 350 CID (5.7 litre) Bore/Stroke 3.74"/3.48" (95/88.4mm) 4.00"/3.48" (101.6/88.4mm) Compression Ratio 8.5:1 Compression Pressure 150 PSI (1035 kPa) 155 PSI (1069 kPa) 150 PSI (1035 kPa) Idie RPM (In Forward Gear) 650-700 Max. RPM (At W.O.T.) 3800-4200 4200-4600 Oil PSI (At 2000 RPM) 30-55 PSI (207-379 kPa) Min. Oil PSI (At Idle) 4 PSI (28 kPa) Fuel Pump PSI (At 1800 RPM) 5-1/2-7 PSI (38-48 kPa) Electrical System 12 Volt Negative (-) Ground Min. Battery Cold Cranking Amps 305 350 Firing Order 1-8-4-3-6-5-7-2 Spark Plug Type AC-MR43T Champion RV8C Autolite-144 NGK-BR6FS Spark Plug Gap .035" (,9mm) Timing (At Idle RPM) 8° BTDC Preliminary Idle Mixture 1-1/4 Turns 2-3 Turns Thermostat 143°F (62°C) 90-95693 1-888 IMPORTANT INFORMATION/TROUBLESHOOTING - 1B-11 TUNE-UP CHART MODEL MCM 330 (B-W) MCM 330 MCM 370/400 Horsepower (Kilowatts) 330 (246) 370 (262) Number of Cylinders V-8 Displacement 454 CID (7.4 litre) Bore/Stroke 4.25"/4.00" (108/101.6mm) Compression Ratio 8.5:1 8.2:1 8.6:1 Compression Pressure 150 PSI (1035 kPa) Idle RPM (In Forward Gear) 650-700 800-850 Max. RPM (At W.O.T.) 4200-4600 4800-5200 Oil PS! (At 2000 RPM) 30-70 PSI (207-483 kPa) Min. Oil PSI (At Idle) 4 PSI (28 kPa) 5 PSI (35 kPa) Fuel Pump PSI (At 1800 RPM) 5-1/2-7 PSI (38 - 48 kPa) 5-1/4 - 6-1/2 PSI (36 - 44 kPa) Electrical System 12 Volt Negative (-) Ground Min. Battery Cold Cranking Amps 450 Firing Order 1-8-4-3-6-5-7-2 Spark Plug Type AC-MR43T Champion RV8C Autolite-144 NGK-BR6FS Dwell 26° -31° Breaker Point Spring Tension 25-30 Oz. (709-850g) Timing (At Idle RPM) 8° BTDC 10° BTDC Preliminary Idle Mixture 2-3 Turns Thermostat 143°F (62°C) 1 B-12 - IMPORTANT INFORMATION/TROUBLESHOOTING 90-95693 1-888 TUNE-UP CHART MODEL MCM 400 CYCLONE MCM 440 CYCLONE MCM 460 CYCLONE MCM 475 TURBO Horsepower (Kilowatts) 400 (298) 440 (328) 460 (343) 475 354 Number of Cylinders V-8 Displacement 454 CID (7.4 litre) 482 CID (7.9 litre) 454 CID (7.4 litre) Bore/Stroke 4.25"/4.00" (108/102mm) 4.25"/4.25" (108/108mm) 4.25"/4.00" (108/102mm) Compression Ratio 8.6:1 9.2:1 7:1 Compression Pressure 150 PSI (1035 kPa) 160 PSI (1103 kPa) 130 PSI (896 kPa) Idle RPM (In Forward Gear) 800-850 Max. RPM (At W.O.T.) 4800-5200 4800-5400 5200-5400 Oil PSI (At 2000 RPM) 35-7C (241-48 PSI 3 kPa) Min. Oil PSI (At Idle) 5 PSI (35 kPa) Fuel Pump PSI (At 1800 RPM) 5-1/4 - 6-1/2 PSI (36 - 44 kPa) ; Electrical System 12 Volt Negative (-) Ground Min. Battery Cold Cranking Amps 450 Firing Order 1-8-4-3-6-5-7-2 Spark Plug Type AC-MR43T Champion RV8C Autolite-144 NGK-BR6FS AC-MR41T Champion-V4C Spark Plug Gap .035" (,9mm) Breaker Point Gap .016" . 019" (.4 - ,45mm) Dwell 28° 31° Breaker Point Spring Tension 25-30 Oz. (709-850g) Timing (At Idle RPM) 10° BTDC 15° BTDC 16° BTDC Preliminary Idle Mixture 2-3 Turns Thermostat 143°F ;62°C) 90-95693 1-888 IMPORTANT INFORMATION/TROUBLESHOOTING - 1B-13 TUNE-UP CHART MODEL MCM 470TR MCM 230TR MCM 260TR Horsepower (Kilowatts) 170 (127) 230 (172) 260 (194) Number of Cylinders 4 V-8 Displacement 224 CID (3.7 litre) 305 CID (5 litre) 350 CID (5.7 litre) Bore/Stroke 4.36"/3.75" (110.7/95.3mm) 3.74"/3.48" (95/88.4mm) 4.00"/3.48" (101.6/88.4mm) Compression Ratio 8.8:1 8.5:1 Compression Pressure 150 PSI (1035 kPa) 155 PSI (1069 kPa) 150 PSI (1035 kPa) Idle RPM (In Forward Gear) 650-700 Max. RPM (At W.O.T.) 3800-4200 4000-4400 Oil PSI (At 2000 RPM) 30-60 PSI (207-414 kPa) 30-55 PSI (207-379 kPa) Min. Oil PSI (At Idle) 4 PSI (28 kPa) Fuel Pump PSI 5 - 6-1/2 PSI (35-44 kPa) 5-1/2-7 PSI (38 - 48 kPa) Electrical System 12 Volt Negative (-) Ground Min. Battery Cold Cranking Amps 450 305 350 Firing Order 1-3-4-2 1-8-4-3-6-5-7-2 Spark Plug Type Same as MIE 470 AC-MR43T Champion - RV8C Autolite-144 NGK-BR6FS Spark Plug Gap .035" (,9mm) Breaker Point Gap .022" (.5mm) Dwell 28° -34° Breaker Point Spring Tension 19-23 Oz. (540-650g) Timing (At Idle RPM) 8° BTDC Preliminary Idle Mixture 1-1/4 Turns 2-3 Turns Thermostat 160°F (71°C) 143°F (62° C) 1 B-14 - IMPORTANT INFORMATION/TROUBLESHOOTING 90-95693 1-888 TUNE-UP CHART MODEL MIE 470 Horsepower (Kilowatts) 170 (127) Number of Cylinders 4 Displacement 224 CID (3.7 litre) Bore/Stroke 4.36"/3.75" (110.7/95.3mm) Compression Ratio 8.8:1 Compression Pressure 150 PSI (1035 kPa) Idle RPM (In Forward Gear) 650-700 Max. RPM (At W.O.T.) 3800-4200 Oil PSI (At 2000 RPM) 30-60 PSI (207-414 kPa) Min. Oil PSI (At Idle) 4 PSI (28 kPa) Fuel Pump PSI (At 1000 RPM) 5 - 6-1/2 PSI (35 - 44 kPa) Electrical System 12 Volt Negative (-) Ground Min. Battery Cold Cranking Amps 450 Firing Order 1-3-4-2 L.H. or R.H. Rotation Spark Plug Type AC-R42TS Champion RV9YC Autolite-13 NGK-BPR6FS Spark Plug Gap .035" (,9mm) Breaker Point Gap .022" (.5mm) Dwell 28° 34° Breaker Point Spring Tension 19-23 Oz. (540-650g) Timing (At Idle RPM) 8° BTOC Preliminary Idle Mixture 1-1/4 Turns Thermostat 160°F (71 °C) 90-95693 1-888 IMPORTANT INFORMATION/TROUBLESHOOTING - 1B-15 TUNE-UP CHART MODEL MIE 228 MIE 255 MIE 330 Horsepower (Kilowatts) 228 (170) 255 (190) 330 (246) Number of Cylinders V-8 Displacement 305 CID (5 litre) 350 CID (5.7 litre) 454 CID (7.4 litre) Bore/Stroke 3.74"/3.48" (95/88.4mm) 4.00"/3.48" (101.6/88.4mm) 4.25"/4.00" (108/101,6mm) Compression Ratio 8.5:1 8.2:1 Compression Pressure 155 PSI (1069 kPa) 150 PSI (1035 kPa) Idle RPM (In Forward Gear) 650-700 Max. RPM (At W.O.T.) 4000-4400 3800-4200 Oil PSI (At 2000 RPM) 30-55 PSI (207-379 kPa) 30-70 PSI (207-483 kPa) Min. Oil PSI (At Idle) 4 PSI (28 kPa) Fuel Pump PSI (At 1800 RPM) 5-1/4-6-1/2 PSI (36 - 44 kPa) Electrical System 12 Volt Negative (-) Ground Min. Battery Cold Cranking Amps 305 350 450 Firing Order L.H. Rot. 1-8-4-3-6-5-7-2 R.H. Rot. 1-2-7-5-6-3-4-8 Spark Plug Type AC-MR43T Champion -RV8C Autolite-144 NGK-BR6FS Spark Plug Gap .035" (,9mm) Breaker Point Gap .016"-.019" (.4-.45mm) Dwell 26° -31° Breaker Point Spring Tension 25-30 Oz. (709-850g) Timing (At Idle RPM) 8° BTDC Preliminary Idle Mixture 2-3 Turns Thermostat 143°F (62° C) 1 B-16 - IMPORTANT INFORMATION/TROUBLESHOOTING 90-95693 1-888 TUNE-UP CHART MODEL MIE 230 MIE 260 MIE 340 Horsepower (Kilowatts) 230 (172) 260 (194) 340 (254) Number of Cylinders V-8 Displacement 305 CID (5 litre) 350 CID (5.7 litre) 454 CID (7.4 litre) Bore/Stroke 3.74"/3.48" (95/88.4mm) 4.00"/3.48" (101.6/88.4mm) 4.25"/4.00" (108/101.6mm) Compression Ratio 8.5:1 Compression Pressure 155 PSI (1069 kPa) 150 PSI (1035 kPa) Idle RPM (In Forward Gear) 650-700 Max. RPM (At W.O.T.) 4000-4400 Oil PSI (At 2000 RPM) 30-55 PSI (207-379 kPa) 30-70 PSI (207-483 kPa) Min. Oil PSI (At Idle) 4 PSI (28 kPa) Fuel Pump PSI (At 1800 RPM) 5-1/2-7 PSI (38-48 kPa) Electrical System 12 Volt Negative (-) Ground Min. Battery Cold Cranking Amps 305 350 450 Firing Order L.H. Rot. 1-8-4-3-6-5-7-2 R.H. Rot. 1-2-7-5-6-3-4-8 Spark Plug Type AC-MR43T Champion - RV8C Autolite-144 NGK-BR6FS Spark Plug Gap .035" (,9mm) Timing (At Idle RPM) 8° BTDC Preliminary Idle Mixture 2-3 Turns Thermostat 143°F (62°C) 90-95693 1-888 IMPORTANT INFORMATION/TROUBLESHOOTING - 1B-17 CAPACITY CHART NOTICE All Capacities are approximate MODEL MCM 120/120R MCM 140/140R MCM 165 Crankcase (with Filter) 4 Qts. (3.8 litres) 5 Qts. (4.7 litres) Standard Cooling System 9 Qts. (8.5 litres) 11 Qts. (10.4 litres) Closed Cooling System 9 Qts. (8.5 litres) 11 Qts. (10.4 litres) Stern Drive Unit 32 Fl. Oz. (.95 litres) MODEL MCM 470 MCM 470R MCM 485 MCM 488R Crankcase (with Filter) 5-1/2 Qts. (5.2 litres) 5-3/4 Qts. (5.4 litres) 6-1/2 Qts. (6.1 litres) Closed Cooling System 10-1/2 Qts. (9.9 litres) 11 Qts. (10.4 litres) 10-1/2 Qts. (9.9 litres) 11 Qts. (10.4 litres) Stern Drive Unit 32 Fl. Oz. (.95 litres) MODEL MCM 898/898R MCM 228/228R MCM 260/260R Crankcase (with Filter) 5 Qts. (4.7 litres) 5-1/2 Qts. (5.2 litres) Standard Cooling System 15 Qts. (14.1 litres) Closed Cooling System 20 Qts. (19 litres) Stern Drive Unit 32 Fl. Oz. (.95 litres) 1B-18 - IMPORTANT INFORMATION/TROUBLESHOOTING 90-95693 485 CAPACITY CHART NOTICE All Capacities are approximate MODEL MCM 330 MCM 330 (B-W) MCM 370/400 Crankcase 6 Qts. 7 Qts. 6 Qts. (with Filter) (5.6 litres) (6.6 I tres) (5.6 litres) Standard 20 Qts. Cooling System (19 litres) Closed 28 Qts. Cooling System (26.5 litres) Transmission 2 Qts. (1.8 litres) Stern Drive 4 Qts. Unit (TR) (3.8 litres) Stern Drive Unit (TRS) 3 Qts. (2.8 litres) MODEL MCM 400/440 CYCLONE MCM 460 CYCLONE MCM 475 TURBO Crankcase 7 Qts. 10 Qts. 8 Qts. (with Filter) (6.6 litres) (9.4 litres) (7.5 litres) Standard 20 Qts. Cooling System (19 litres) Transmission 2 Qts. (1.8 litres) Stern Drive Unit (TRS) 3 Qts. (2.8 litres) 90-95693 485 IMPORTANT INFORMATION/TROUBLESHOOTING - 1B-19 CAPACITY CHART NOTICE All Capacities are approximate MODEL MCM 470TR MCM 230TR MCM 260TR Crankcase (with Filter) 5-1/2 Qts. (5.2 litres) 6 Qts. (5.6 litres) Standard Cooling System 15 Qts. (14.1 litres) Closed Cooling System 10-1/2 Qts. (9.9 litres) 20 Qts. (19 litres) Transmission 2 Qts. (1.8 litres) Stern Drive Unit (TR) 4 Qts. (3.8 litres) 1B-20 -IMPORTANT INFORMATION/TROUBLESHOOTING 90-95693 485 CAPACITY CHART NOTICE All Capacities are approximate MODEL MIE 470 MIE 228/255 MIE 330 Crankcase (with Filter) 5-1/2 Qts. (5.2 litres) 6 Qts. (5.6 litres) 7 Qts. (6.6 litres) Standard Cooling System 15 Qts. (14.1 litres) 20 Qts. (19 litres) Closed Cooling System 10-1/2 Qts. (9.9 litres) 20 Qts. (19 litres) 28 Qts. (26.5 litres) Transmission 1:1 2 Qts. (1.8 litres) Transmission 1.5:1-3.0:1 3 Qts. (2.8 litres) Transmission V-Drive 4 Qts. (3.8 litres) MODEL MIE 230 MIE 260 MIE 340 Crankcase (with Filter) 6 Qts. (5.6 litres) 7 Qts. (6.6 litres) Standard Cooling System 15 Qts. (14.1 litres) 20 Qts. (19 litres) Closed Cooling System 20 Qts. (19 litres) 28 Qts. (26.5 litres) Transmission 1:1 2 Qts. (1.8 litres) Transmission 1.5:1-3.0:1 3 Qts. (2.8 litres) Transmission V-Drive 4-1/2 Qts. (4.2 litres) 90-95693 485 IMPORTANT INFORMATION/TROUBLESHOOTING - 1B-21 FUEL, OIL, FLUID and COOLANT SPECIFICATIONS FUEL Use of improper gasoline can damage the engine seriously. Engine damage, that results from use of improper gasoline, is considered misuse of the engine and is not covered under MerCruiser Warranty. The use of anv good grade regular leaded, premium, low-lead or lead-free automotive gasolines with a minimum posted octane rating of 86 (research octane number 90), are satisfactory for use in MerCruiser marine engines. [Hi-Performance models: Minimum posted octane rating of 88 (research octane number 93). If 88 octane is not available, a gasoline with an average octane rating as low as 86 (research octane number 90) may be used: however, ignition timing must be retarded 4° to prevent harmful detonation.] However, gasolines containing alcohol, either methyl alcohol (methanol) or ethvl alcohol (ethanol) may cause increased: • Corrosion of metal parts • Deterioration of elastomer and plastic parts • Fuel permeation through flexible fuel lines • Wear and damage of internal engine parts • Starting and operating difficulties. Some of these adverse effects are due to the tendency of gasolines containing alcohol to absorb moisture from the air. resulting in a phase of water and alcohol separating from the gasoline in the fuel tank. The adverse effects of alcohol are more severe with methyl alcohol (methanol) and are worse with increasing alcohol content. FIRE AND EXPLOSION HAZARD: Fuel leakage from any part of the fuel system can be a fire and explosion hazard which can cause serious bodily injury or death. Careful periodic inspection of the entire fuel system is mandatory, particularly after storage. All fuel components including fuel tanks, whether plastic, metal or fiberglass, fuel lines, fittings, fuel filters, fuel pumps and carburetors should be inspected for leakage, softening, hardening, swelling or corrosion. Any sign of leakage or deterioration necessitates replacement before further engine operation. Because of the possible adverse effects of alcohol in gasoline, it is recommended that only alcohol free gasoline be used where possible. If only alcohol containing fuel is available, or if the presence of alcohol is unknown, then increased inspection frequency for leaks and abnormalities is required. No Lead Gasoline/Alcohol Blends LEAD Recent regulations by the L.S. Environmental Protection Agencv (EPA) and the Canadian government have required the removal of lead (anti-knock compound) from all gasoline by 1988 due tc the lead emission in exhaust being a health hazard. In order to maintain octane ratings, many gasoline manufacturers are adding ethyl alcohol (ethanol) or methyl alcohol (methanol) to the gasoline to replace the lead. Since 1975. Mercury Marine has recommended operation of MerCruiser marine engines with any good grade regular leaded, premium, low-lead or no-lead gasolines with a minimum average octane rating of 88. Prior to that time, recommendations were to use one tank of leaded gasoline for every four tanks of no-lead gasoline. Mercury Marine has recently amended its fuel recommendations for MerCruiser engines. NO LEAD GASOLINE WITH A MINIMUM POSTED AVERAGE OCTANE RATING OF 86, MAY BE USED IN MERCRUISER MARINE ENGINES AS STATED ABOVE. (HI-PERFORMANCE MODELS ARE EXCEPTIONS.) GASOLINE/ALCOHOL BLENDS Manv new motor vehicleowner manualsare warning about the potential damage from using gasoline containing alcohol, especially METHANOL. They cite possible fuel system damage and performance problems. These are just two of the hazards that may be caused by alcohol. These same problems as well as theadditional safety risk of fireand explosion from fuel system leaks appiv to marine inboard engines. METH ANOL is more severe in its bad effects than is ETHANOL. Alcohol is also more severe in older engines since newer engines have materials which are more resistant to alcohol. EFFECTS OF GASOLINE/ALCOHOL BLENDS ON MARINE ENGINES Corrosion of metals may result from use of alcohol-gasoline blends. Portable or permanently installed fuel tanks of metal or fiberglass, fuel filters, fuel lines and float bowls may be affected by alcohol blended fuels. Many fiberglass fuel tanks are slowly dissolved by alcohol. leading immediately to filter and carburetor plugging and eventually to fuel tank failure. Alcohol containing fuels will absorb moisture from the air. At first, this moisture will remain in solution, but once the water content of the fuel has built up to about one-half of one percent, it will separate out. (phase separation) bringing the alcohol with it. This alcohol-water mixture settles to the bottom of the fuel tank and if this mixture gets into the engine, engines can be seriously damaged internally, as it may wash the protective film of oil off the bore of any cvlinder that it enters. Before the engine can be restarted, it is necessary to remove the separated alcohol and water layer, flush ou: the fuel system with clean fuel and remove and dry the spark plugs. 1A-10- IMPORTANT iN FORM ATI ON/TROUBLESHOOTING 90-95693 485 BOAT/MOTOR STORAGE W hen operating a MerCruiser on gasoline containing alcohol, storage of gasoline in the fuel tank for long periods of time should be avoided. Long periods of storage, common to boats, create unique problems. In cars, gasoline/alcohol blend fuels normally are consumed before they can absorb enough moisture to cause trouble, but boats often sit idle long enough for phase separation to take place. In addition, internal corrosion may take place during storage if alcohol has washed protective oil films from internal components. WINTER STORAGE If boat is to be placed in winter storage, carburetors must be run drv at idle RPM. Permanent fuel tanks should be drained completely and Quicksilver Gasoline Stabilizer and Conditioner added to any fuel remaining in the tank. Portable fuel tanks should be emptied completely. It is also recommended to coat the internal engine parts with Quicksilver Storage Seal. Follow the directions on the container. This coating will reduce possibilities of internal parts becoming rusted from moisture accumulation during storage. WARRANTY Performance problems, fuel svstem or other damage resulting from the use of gasoline-alcohol blended fuels is not the responsibilitv of Mercury Marine and will not be covered under our warrantv. CONTINUING EVALUATIONS The effects of gasoline blended with ETHANOL and METHANOL are still being evaluated by the United States Coast Guard, the National Marine Manufacturers Association (NMMA), Mercury Marine and other engine and boat manufacturers. We have recommended pump posting of alcohol content of gasoline. Further we recommend using gasoline known not to contain any METHANOL or ETHANOL when possible. TEST FOR ALCOHOL CONTENT IN GASOLINE The following is an acceptable and widely used field procedure for the detection of alcohol in gasoline. (Outboard motors only: It should be conducted on the fuel before the addition of oil as the oil may obscure any change in separation level.) L se anv small transparent bottle or tube that can be capped and is or can be provided with graduations or a mark at about 1/3 full. A pencil mark on a piece of adhesive tape may be used. PROCEDURE Fill the container with water to the mark. Add fuel almost to fill the container, leaving some air space, and then cap the container. The proportions of fuel to water are not critical, but there should be 2-3 times as much fuel as water. 3. Shake container vigorously and allow it to sit upright for up to about 3-5 minutes. If the volume of water appears to have increased, alcohol is present. If you are not sure, there is not enough to be of concern. If the dividing line between water and fuel becomes cloudy, use the middle of the cloudy band. CRANKCASE OIL After the 20-hour break-in oil has been drained, select a crankcase oil based on the prevailing daytime temperature in the area in which the boat is operated. The chart below is the guide to crankcase oil selection and recommended change intervals. Oil filter should always be changed with oil. To help obtain optimum engine performance and to provide maximum protection, we strongly recommend the use of Quicksilver 4-Cvcle Marine Engine Oil. If not available, however, a good grade detergent automotive oil of correct viscosity, that has an API classification of "SE" or "SF", may be used. IMPORTANT: The use of multi-viscosity oils specifically is not recommended for use in MerCruiser Engines. In those areas, however, where the recommended straight weight oil is not available, a multi- viscosity 20W-40 ("SE" or "SF") or, as a second but less preferable choice, 20W-50 ("SE" or "SF") may be used. The use of multi-viscosity oils (other than 20W-40 or 20W-50), oils which contain "solid" additives, non-detergent oils, or low quality oils specifically are not recommended. 90-95693 485 IMPORTANT INFORMATION/TROUBLESHOOTING - 1A-11 POWER STEERING IMPORTANT: Use only automatic transmission fluid (ATF), Dexron® or Dexron II in PowerSteering System. TRANSMISSION MERCURY MARINE TRANSMISSION Dexron® II, Type F or any other automatic transmission fluids (ATF) currently used in passenger cars are suitable for use in transmission. VELVET DRIVE® (BORG-WARNER) Dexron® II, Type F, or other hydraulic transmission Fluids which meet the Detroit Diesel Allison Type C3 specifications are recommended for use in all Velvet Drive® marine transmissions. COOLANT Alcohol or Methanol base anti-freeze or plain water, are not recommended for use in fresh water section of cooling system at any time. It is recommended that the coolant section of Closed Cooling System be filled with a 50/50 mixture of ethylene glycol anti-freeze and water. In areas where the possibility of freezing DOES NOT exist, it is permissible to use a solution of rust inhibitor and water (mixed to manufacturer's recommendations). Any brand of permanent type anti-freeze solution that is made for aluminum component engines can be used in aluminum MerCruiser engines. DO NOT MIX the new anti-freeze solution with the old solution or it will cause small particles to form in the coolant. These small particles can settle in the heat exchanger and restrict coolant flow. Drain and flush the old anti-freeze solution from the closed cooling system. All other MerCruiser engine can use any type of permanent anti-freeze or anv brand anti-freeze solution that meets G.M. specification 1825.VI. 1A-10- IMPORTANT iN FORM ATI ON/TROUBLESHOOTING 90-95693 485 MAINTAINING CRANKCASE OIL LEVEL OVER-FILLING ENGINE CRANKCASE Over full crankcases (oil level being too high) can cause a fluctuation or drop in oil pressure and rocker arm "clatter", on MerCruiser engines. The over-full condition results in the engine crankshaft splashing and agitating the oil, causing it to foam (become aerated). The aerated oil caused the hydraulic valve lifters to "bleed down". This, in turn, results in rocker arm "clatter" and loss of engine performance, due to the valves not opening properly. Care must be taken when checking engine oil level. Oil level must be maintained between the "add mark" and the "full mark" on the dipstick. To ensure that you are not getting a "false reading", make sure the following steps are done before checking the oil level. 16041 • Boat "at rest" in the water, OR • If boat is on a trailer, raise or lower bow until the boat is a - Dipstick setting at the approximate angle that it would be if setting b - Oil Level "at rest" in the water. • Allow sufficient time for oil to drain into the crankcase if Figure 1. Oil Level (Typical Engine) engine has just been run or oil has just been added. CHECKING LEVEL/FILLING 1. Stop engine and allow boat to come to a rest. 2. Allow oil to drain back into oil pan - approximately 5 minutes. 3. Remove dipstick (Figure 1) - Wipe clean and reinstall. Push dipstick all-the-way into dipstick tube. 4. Remove dipstick and note the oil level. 5. Oil level must be between the "FULL" and "ADD" marks. (Figure 1) 6. If oil level is below "ADD " mark, proceed to step 7 and 8. 7. Remove oil filler cap from valve rocker arm cover. (Figure 2) 8. Add required amount of oil to bring level up to. but not over, the "FULL" mark on dipstick. 16001 a " Cap Figure 2. Adding Oil (Typical Engine) 90-95693 485 IMPORTANT INFORMATION/TROUBLESHOOTING - 1A-11 CHANGING OIL and FILTER CHANGING OIL 1. Start engine and run until it reaches normal operating temperatures. IMPORTANT: Change oil when engine is warm from operation, as it flows more freely, carrying away more impurities. 2. Stop engine. 3. Remove drain plug from oil pan. and allow oil to drain into suitable container, or pan. (Figure 1) IMPORTANT: If drain plug is not accessible because of boat construction, oil may be removed thru dipstick tube. (Figure 2) a - Dipstick Tube 4. After oil has drained completely, reinstall drain plug and Figure 2. Dipstick Tube (Typical Engine) tighten securely. 16002 a - Drain Plug Figure 1. Drain Plug (Typical Engine) 5. Fill crankcase with specified oil as outlined in "Maintaining Crankcase Oil Level" in this section. IMPORTANT: ALWAYS use dipstick to determine exact quantity of oil required. DO NOT overfill. CHANGING FILTER 1. Remove and discard oil filter and its sealing ring. (Figure 3) 2. Coat sealing ring (Figure 4) on new filter with engine oil. and install new filter. Tighten filter SECURELY, BUT DO NOT OVER-TIGHTEN. 16095 16006 a - Oil Filter Figure 3. Changing Oil Filter (Typical Engines) 1A-10- IMPORTANT iN FORM ATI ON/TROUBLESHOOTING 90-95693 485 16043 16043 a - Sealing Ring - Coat with Engine Oil Figure 4. Sealing Ring (Typical Filter) MAINTAINING POWER STEERING FLUID LEVEL IMPORTANT: Use only automatic transmission fluid (ATF), Dexron or Dexron II in Power Steering System. With Engine Cold 1. Stop engine and position drive unit so that it is straight back. 2. Remove fill cap/dipstick from Power Steering pump and note fluid level. (Figure 1) 3. Level should be between "FULL COLD" mark and bottom of dipstick. (Figure 2) 4. If fluid level is below bottom of dipstick, but f.uid is still visible in pump reservoir, add required amount of automatic transmission fluid (ATF), thru fill cap opening, to bring level up to "FULL COLD" mark on dipstick. DO NOT OVERFILL. With Engine Warm from Operation 1. Stop engine and position drive unit so that it is straight back. 2. Remove fill cap/dipstick from Power Steering pump and note fluid level. (Figure 1) 3. Level should be between "FULL HOT" mark and "ADD " mark on dipstick. (Figure 2) 4. If level is low (beiow "ADD " mark), but fluid is still visible in pump reservoir, add required amount of automatic transmission fluid (ATF), thru fill cap opening, to bring level up to "FULL HOT" mark on dipstick. DO NOT OVERFILL. 90-95693 485 IMPORTANT INFORMATION/TROUBLESHOOTING - 1A-11 a - Fill Cap/Dipstick Figure 1. Checking Fluid Level a - Engine Cold b - Engine Warm Figure 2. Fill Cap/Dipstick FILLING and BLEEDING SYSTEM IMPORTANT: Power Steering system MUST BE filled exactly as explained, following to be sure that all air is bled from the system. All air must be removed, or fluid in pump may foam during operation and be discharged from pump reservoir. Foamy fluid also may cause Power Steering system to become spongy, which may result in poor boat control. 1. Position drive unit so that it is straight back. Remove shipping cap from Power Steering pump and check fluid level with dipstick attached to fill cap. Add automatic transmission fluid (ATF), as required, to bring level up to "Full-Cold" mark on dipstick. IMPORTANT: Use only automatic transmission fluid (ATF), Dexron or Dexron II in Power Steering System. 2. Turn steering wheel back-and-forth to end of travel in each direction several times; then recheck fluid level and add fluid, if necessary. 3. Install vented fill cap. DO NOT operate engine without water being supplied to seawater pickup pump or pump impeller may be damaged and subsequent overheating damage to engine may result. 4. Start engine and run at fast idle (1000-1500 RPM) until engine reacnes normal operating temperature. During this time, turn steering wheel back-and-forth to end of travel in each direction several times. 5. Position drive unit so that it is straight back and stop engine. Remove fill cap from pump. Allow any foam in pump reservoir to disperse, then check fluid level and add fluid, as required, to bring level up to "Full-Hot" mark on dipstick. DO NOT OVERFILL. Reinstall fill cap securely. IMPORTANT: Drive unit MUST BE positioned straight back and Power Steering fluid MUST BE hot to accurately check fluid level. 6. If fluid is still foamy (in Step5). repeat Steps4and5 until fluid does not foam and level remains constant. 90-95693 485 1A-10- IMPORTANT iN FORM ATI ON/TROUBLESHOOTING MAINTAINING TRANSMISSION FLUID LEVEL BORG-WARNER TRANSMISSION IMPORTANT: Use only recommended fluid. Transmission fluid should be checked when starting engine each day. as follows: 1. Remove dipstick. Check to ensure that fluid is indicated on dipstick. Fluid level may be somewhat over full mark, as some of the fluid from transmission fluid cooler and hoses may have drained back into transmission. If low. add automatic transmission fluid (ATF) until level comes up to full mark on dipstick. 3. Stop engine and QUICKLY check fluid level. Add automatic transmission fluid, if necessary, to bring level up to full mark on dipstick. 4. Reinstall dipstick. 5. If transmission fluid level was extremely low, carefullv check transmission, fluid cooler and hoses for leaks. MERCURY MARINE TRANSMISSION IMPORTANT: Use only recommended fluid. a - Dipstick b - Full Mark c - Dipstick Tube Figure 1. Checking Transmission Fluid Level IMPORTANT: To accurately check fluid level, engine MUST BE run at 1500 RPM for 2 minutes immediately prior to checking level. 2. Start engine and run at 1500 RPM for 2 minutes to fill all hydraulic circuits. IMPORTANT: Be sure to push dipstick all-the-way down into dipstick tube when checking fluid level. Transmission fluid level should be checked before starting engine each day. Check level with dipstick, located on starboard (right) side of transmission. (Figure 2) Fluid level should be maintained between "Full''' and "Add" marks on dipstick. If low. add recommended fluid thru dipstick tube to bring level up to "Full" mark. a - Dipstick Figure 2. Transmission Dipstick Location 90-95693 485 IMPORTANT INFORMATION/TROUBLESHOOTING - 1A-11 MAINTAINING COOLANT LEVEL Allow engine to cool down before removing pressure cap. Sudden loss of pressure could cause hot coolant to boil and discharge violently. After engine has cooled down, turn cap Vs-turn to allow any pressure to escape slowly, then, push down and turn cap all-the-way ofl. 1. Coolant level in heat exchanger should be within 1" (25mm) from bottom of filler neck. IMPORTANT: When reinstalling pressure cap, be sure to tighten it until it contacts stops on fill neck. 2. Coolant level should be between the "Add" and "Full" mark on coolant recoverv reservoir with engine at normal operating temperature. (Figure 1) 193-HR a - Fill Cap Figure 1. Coolant Recovery Bottle FLUSHING COOLING SYSTEM If engine is operated in salty, polluted or mineral-laden waters, cooling svsiem should be flushed periodically (preferably after each use) to reduce corrosion and prevent theaccumulalion of deposits in the svstem. Cooling system also should be thoroughlv flushed prior to storage. When flushing cooling system with boat out of water, be certain that area in vicinity of propeller is clear and that no person is standing nearby. IMPORTANT: DO NOT run engine above 1500 RPM, as suction created by seawater pickup pump may collapse water supply hose and cause engine to overheat. IMPORTANT: If cooling system is to be flushed with boat in the water, water inlet valve (if so equipped) must be closed, or water inlet hose MUST BE disconnected and plugged to prevent water from flowing into boat. Watch temperature gauge at dash to ensure that engine does not overheat. BELT DRIVEN SEAWATER PICKUP PUMP 1. Loosen hose clamp arid remove water inlet hose at location shown in Figure 1 or 2. IMPORTANT: MCM 898/898R/228/228R/260/260R Engines: if engine has a Closed Cooling system or is a Drive Shaft Extension model refer to Figure 3 also, if cooling system is going to be flushed with boat out of the water. Two independent water connects are required on these models. a - Seawater Pickup Pump b - Seawater Inlet Hose Figure 1. All V-8 Engines Except MCM 370/400 and Hi-Performance 454 CID Engines. 1A-10- IMPORTANT iN FORM ATI ON/TROUBLESHOOTING 90-95693 485 STERN DRIVE UNIT SEAWATER PICKUP PUMP a - Disconnect Hose - Cooling Water Must Flow Thru Cooler(s) if Engine is so Equipped Figure 2. MCM 370/400 and Hi-Performance Engines 10181 a - Flush Device b - Garden Hose Figure 3. Flush Device on Stern Drive 3. Place the remote control lever in neutral position and start the engine. Operate engine at idle speed in neutral gear for 10 minutes or until discharge water is clear, then stop engine. 4. Shut off w ater tap. Remove flushing connector from pump inlet and reconnect water inlet hose. Be sure to tighten clamp securelv. 1. Install Flush Device and connect garden hose between it and water tap. (Figure 3) 2. Salt water areas and boat in the water: a. Raise stern drive unit to full trailer position. b. Install flush device over water intake holes. (Figure 4) c. Lower stern drive unit to full down position. a - Minimum Water Level b - Water Intake Holes Figure 4. Minimum Water Level 3. Partially open water tap (approx. V2 maximum capacity) and allow cooling system to fill completely. Cooling system is full when water is discharged thru the propeller. DO NOT use full water tap pressure. 4. Place remote control in neutral position and start engine. Watch temperature gauge on instrument panel to ensure that engine does not overheat. 5. Stop engine, turn off water tap and remove Flush Device. 90-95693 485 IMPORTANT INFORMATION/TROUBLESHOOTING - 1A-11 LUBRICATION SHIFT CABLE THROTTLE CABLE 16005 a SAE 30W Engine Oil 16086 b - Quicksilver 2-4-C Multi-Lube a - SAE 30W Engine Oil Figure 3. Typical MCM 120-260 Stern Drive Model b - Quicksilver 2-4-C Multi-Lube Figure 1. Typical 2 Barrel Carburetor 16426 a - SAE 30W Engine Oil b - Quicksilver 2-4-C Multi-Lube Figure 2. Typical 4 Barrel Carburetor a - SAE 30W Engine Oil b - Quicksilver 2-4-C Multi-Lube Figure 4. Typical MCM 330 - 475 Turbo Stern Drive Model 1 B-32 - IMPORTANT INFORMATION/TROUBLESHOOTING 90-95693 485 ENGINE COUPLING/"U"-JOINT SPLINES (MCM 120-260) a-SAE SOW Engine Oil a - Quicksilver 2-4-C Multi-Lube b - Quicksilver 2-4-C Multi-Lube Figure 7. Typical MCM 120-260 Stern Drive Model Figure 5. Typical MCM 330 - 475 Turbo Stern Drive Model a - SAE 30W Engine Oil b - Quicksilver 2-4-C Multi-Lube Figure 6. Typical MIE 470 - 340 Inboard Model a - Quicksilver 2-4-C Multi-Lube Figure 8. Typical MCM 120-260 Stern Drive Model IMPORTANT INFORMATION/TROUBLESHOOTING - 1A-11 90-95693 485 "IT-JOINT SHAFT SPLINE (STERN DRIVE DRIVESHAFT EXTENSION MODELS MODELS WITH BORG-WARNER (MCM 120R/140R and 898/228/260) TRANSMISSION) 14783 0744S 14784 a - Quicksilver 2-4-C Multi-Lube Figure 9. TR/TRS Stern Drive Unit OUTPUT HOUSING (STERN DRIVE WITH MERCURY MARINE TRANSMISSION) a - Quicksilver 2-4-C Multi-Lube Figure 11. Transom End a - Quicksilver 2-4-C Mulii-Lube b - Bell Housing Figure 10. Transmission Output Housing Bearing a - Quicksilver 2-4-C Multi-Lube Figure 12. Engine End 1A-10- IMPORTANT iN FORM ATI ON/TROUBLESHOOTING 90-95693 485 a - Quicksilver 2-4-C Multi-Lube Figure 13. Stern Drive Unit STAGGERED ENGINE (MCM 370 - 475 TURBO) a - Quicksilver 2-4-C Multi-Lube Figure 16. Driveshaft (Engine End) STARTER MOTOR LUBRICATION MCM 330 (B-W) and MIE 230/260/340 Only When performing the following procedure, be sure to observe the following: • Be sure that engine compartment is well ventilated and that no gasoline vapors are present, to avoid the possibility of a fire. • Be sure to keep hands, feet and clothing clear of engine moving parts. • Be sure to ground coil hi-tension wire to block. Failure to ground coil wire may cause damage to ignition coil, in addition to being a safety hazard. a - Quicksilver 2-4-C Multi-Lube b - Bell Housing Figure 14. Tailstock Assembly a - Quicksilver 2-4-C Multi-Lube Figure 15. Taiistock and Driveshaft (Transom End) 14903 a - Remove ignition coil hi-tension wire trom distributor cap tower and ground it to engine block with jumper wire. While cranking engine with starter motor lubricate starter motor front bushing thru oil cover with Lubriplate Extra-Heavy Gear Shield or its equivalent. Reinstall coil hi-tension wire, b - Remove plastic plug from flywheel housing. Lubricate starter motor shaft with Lubriplate Extra-Heavy Gear Shield thru hole in flywheel housing. Reinstall plastic plug. Figure 17. Starter Motor MCM 470TR/230TR/260TR On these models, follow Figures 1 or 2. 4. 5. and 6 for lubrication STEERING SYSTEM/STERN DRIVE Refer to "Stern Drive Service Manual" 90-95693 485 IMPORTANT INFORMATION/TROUBLESHOOTING - 1A-11 COMPRESSION TEST OUT-OF-SEASON STORAGE PRECAUTIONS Be sure that engine compartment is well ventilated and that there are no gasoiine vapors present during the following operation ~ to prevent a potential fire hazard. 1. Remove and ground coil high tension lead from distributor cap tower. Remove any foreign matter from around plugs bv blowing awav with compressed air. then remove plugs. 01389 2. Remove flame arrestor and block throttle and choke in wide open pjosition. 3. I nsert compression gauge 1 irmlv in spark plug port. (Fiaure 1) 4. Crank engine thru at least 4compression strokes to obtain highest possible reading. 5. Check and record compression of each cylinder. Compression should read as indicated in "Tune-l p ("hart" in this section. Variation between highest and lowest reading cvlinders should be less than 20 psi (138 kPa). 6. If one or more cylinders read low or uneven, inject a tablespoon of engine oil on top of pistons thru spark plug port. Crank engine several times and recheck compression. 7. Checking results: a. If compression increases, but does not necessarilv reach normal, rings are worn. b. If compression does not improve, valves arestickingor seating poorly. c. If 2 adjacent cylinders indicate low compression and injecting oil does not increase compression, the cause rria\ be a head gasket leak between cylinders with resulting engine coolant and/or oil in cylinders. Figure 1. Checking Compression Be careful when changing fuel filters or while working on fuel system; gasoline is extremely flammable and highly explosive under certain conditions. Be sure that ignition key is "OFF" and do not smoke or allow sources of spark and/or open flames in the area. Be sure that engine compartment is well- ventilated and that there are no gasoline vapors present during starting or "Fogging" of engine — to prevent a potential fire hazard. 1B-36- IMPORTANT INFORMATION/TROUBLESHOOTING 90-95693 485 LAYUP NOTICE Refer to "Precautions", in this section, BEFORE proceeding. 1. Fill fuel tank(s) with fresh gasoline and a sufficient amount of Quicksilver Gasoline Stabilizer and Conditioner to treat the gasoline. 2. Replace all fuel filters. ("Section 4") 3. Start engine and check for fuel leaks. 4. Run engine sufficiently to bring it up to normal opening temperature, then shut off engine and change oil and oil filter. ("Section 1. Part B") 5. Models V> ith Transmission: Change transmission fluid. ("Section 8"). 6. If boat has been operated in salty, polluted or mineral- laden waters, flush cooling system. ("Section 1. Part B'') 7. Remove flame arrestor assembly and restart engine. hile operatingengineat fast idle (1000-1500RPM), fog internal surfaces of induction system and combustion chambers by squirting approximately 8 ounces (227 grams) of Quicksilver Storage Seal or if not available. SAF.20 SE engine oil into carburetor bores. Stall engine by squirting last 2 ounces (57g) of Storage Seal or oil rapidly into carburetor. Turn ignition to "Off". 8. Close fuel shut off valve, if so equipped. 9. Clean flame arrestor and crankcase ventilation hoses and reinstall. ("Section 4") 10. Lubricate all items outlined in "Lubrication' . ("Section 1. Part B") 11. Drain cooling system. ("Section 7") 12. Closed Cooling; System Models: Check coolant (with anti-freeze tester) to ensure that solution is set for lowest temperature expected during storage. 13. Service battery(s). ("Section 3, Part A") 14. Clean outside of engine and repaint any surfaces, which have become bare with Quicksilver Primer and Quicksilver Spray Paint. After paint has dried, spray Quicksilver Corrosion and Rust Preventive Type II on exterior surfaces of engine. If Corrosion and Rust Preventive Type II is not available, wipe down engine with a cloth that is saturated with Quicksilver Storage Seal or SAE 20 SE engine oil. 15. Stern Drive Models: Refer to "Stern Drive Service Manual". 16. Inboard Models: Disconnect propeller shaft coupling from transmission coupling. 90-95693 485 IMPORTANT INFORMATION/TROUBLESHOOTING - 1A-11 R ECO M MISSIONING NOTICE Refer to "Precautions", in this section, BEFORE proceeding. 1. Check thai all cooling system hoses are connected properly. that drain plugs are installed and that petcocks are closed. ("Section 7 i 2. Inspect all drive belts. 3. Check engine alignment. ("Section 2") 4. Perform ALL lubrication and maintenance specified for completion "At Least Once Each Year" in "Maintenance ('hart", except items which were performed at time of engine layup. ("Section 1. Part B") 5. Stern Drive Models: If removed, install stern drive unit. ("Stern Drive Service Manual"). 6. Inboard Models: Reconnect propeller shaft coupling. ("Section 2. Part I") When installing battery (in next step), be sure to connect negative (grounded) battery cable to negative (-) battery terminal and positive battery cable to positive (+) terminal. If battery cables are reversed, damage to electrical system WILL result. 7. Install fully-charged battery. Clean battery cable clamps and terminals and reconnect cables. Be sure to tighten clamps securely. Apply a thin coat of oetroleum base grease to clamps and terminals to help retard corrosion. 8. Start engine and closely observe instrumentation to ensure that all svstems are functioning properly. 9. Carefully inspect entire engine for fuel, oil, water and exhaust leaks. 10. Check fuel pump sight tube (or glass). ("Section 4") 11. Check steering system and shift and throttle control for proper operation. 1C-12- IMPORTANT iNFC'RM ATI ON/TROUBLESHOOTING 90-95693 485 INDEX Page Precautions 1C-1 Used Spark Plug Analysis 1C-2 Poor Boat Performance and/or Poor Maneuverability 1C-4 Improper Full Throttle Engine RPM 1C-5 RPM Too High 1C-5 RPM Too Low 1C-5 Engine Cranks Over But Will Not Start or Starts Hard 1C-6 Important Information 1C-6 Conventional Ignition (No Spark) 1C-6 Thunderbolt IV (HEI) Ignition (No Spark) ................ 1C-6 Thunderbolt IV (HEI) Ignition Test 1C-7 Fuel System Rich 1C-8 Fuel System Lean 1C-8 Miscellaneous 1C-8 Engine Will Not Crank Over 1C-9 Charging System Inoperative 1C-9 Noisy Alternator 1C-9 Instrumentation Malfunction 1C-10 Radio Noise 1C-10 Poor Fuel Economy 1C-10 Carburetor Malfunctions 1C-11 Engine Runs Poorly at Idle 1C-12 Engine Acceleration Is Poor 1C-12 Engine Runs Poorly at High RPM 1C-13 Troubleshooting with Vacuum Gauge 1C-13 Engine Noise 1C-14 Important Information 1C-14 Valve Cover Area....................................................1C-14 Cylinder Area 1C-14 Camshaft Area 1C-14 Crankshaft Area 1C-15 Miscellaneous 1C-15 Oil Pressure 1C-16 Important Information 1C-16 Low Oil Pressure 1C-17 Page High Oil Pressure 1C-17 Excessive Oil Pressure 1C-17 Water in Engine 1C-18 Important Information 1C-18 Water on Top of Pistons 1C-18 Water in Crankcase Oil 1C-18 Engine Overheats (Mechanical) 1C-19 Engine Overheats (Cooling System) 1C-20 Insufficient Water Flow from MC-I Stern Drive Seawater Pickup Pump 1C-21 Insufficient Water Flow from Belt Driven Seawater Pickup Pump 1C-21 Borg-Warner Transmission Malfunctions 1C-22 Neutral 1C-22 Forward Gear 1C-22 Reverse Gear 1C-22 All Gears 1C-23 Leaks 1C-23 Miscellaneous 1C-23 Mercury Marine Transmission Malfunctions 1C-24 Neutral 1C-24 Forward Gear 1C-24 Reverse Gear 1C-24 All Gears 1C-25 Leaks ... 1C-25 Miscellaneous 1C-25 Power Steering 1C-26 Poor, Erratic or No Assist 1C-26 Noisy Pump 1C-26 Fluid Leaks 1C-26 NOTICE Refer to "Precautions", BEFORE proceeding with troubleshooting. PRECAUTIONS Always disconnect battery cables from battery BEFORE working on fuel system to prevent fire or explosion. Be careful when cleaning flame arrestor and crankcase ventilation hose; gasoline is extremely flammable and highly explosive under certain conditions. Be sure that ignition key is "OFF". DO NOT smoke or allow sources of spark or open flame in area when cleaning flame arrestor and crankcase ventilation hose. Be careful when changing fuel system components; gasoline is extremely flammable and highly explosive under certain conditions. Be sure that ignition key is "OFF". DO NOT smoke or allow sources of spark or flame in the area while changing fuel filter. Wipe up any spilled fuel immediately. Make sure no fuel leaks exist, before closing engine hatch. DO NOT operate engine without cooling water being supplied to water pickup holes in gear housing, or water pump impeller will be damaged and subsequent overheating damage to engine may result. DO NOT operate engine without water being supplied to seawater pickup pump on engine, or pump impeller may be damaged and subsequent overheating damage to engine may result. Engine may be operated with boat out-ofwater, if instructions, under "Flushing Cooling System" in "Section 7, Part A" are followed. When running engine with boat out of water, be certain that area in vicinity of propeller is clear and that no person is standing nearby. As a precautionary measure, it is recommended that the propeller be removed. DO NOT run engine above 1500 RPM, as suction created by seawater pickup pump may collapse water supply hose and cause engine to overheat. Be sure that engine compartment is well ventilated and that no gasoline vapors are present to prevent the possibility of a FIRE. DO NOT leave helm unattended while performing tests. 90-95693 485 IMPORTANT INFORMATION/TROUBLESHOOTING - 1A-11 USED SPARK PLUG ANALYSIS Use the following illustrations to help reach a decision that plug is or is not serviceable and can be restored by cleaning, filing and regapping. Spark plug condition also can suggest a variety of possible engine malfunctions and, therefore, can indicate needed engine repairs. When old plugs are replaced, entire set should be replaced. Plug service should be performed onlv on those plugs suitable for additional service, using the following procedures: • Remove any oil deposits with solvent and dry plugs thoroughly. • Open electrode gap wide enough to permit cleaning and filing. • Remove combustion deposits from firing end of spark plug with a plug cleaner. Blow off with compressed air to remove abrasives. • File electrode surfaces to restore clean, sharp edges. Again remove filings with compressed air. • Reset gap to specifications by bending only side electrode with proper tool. NORMAL CONDITION Few deposits are present and probably will be light tan or gray in color. This plug shows that plug heat range is comoatible with engine, and engine is electrically and mechanically in good running condition. W:ith proper plug servicing (clean, file and regap). this plug can be reinstalled with good results. Figure 1. 08958 Normal Condition CHIPPED INSULATOR Chipped insulator usually results from careless plug regapping. I nder certain conditions, severe detonation also can split insulator firing ends. Plug must be replaced. 08957 Figure 2. Chipped Insulator WET FOULING (OIL DEPOSITS) Plug becomes shorted by excessive oil entering combustion chamber, usually in engine with many hours of operation. Worn piston rings, cylinder walls, valve guides or valve stem seals are causes of oil entering combustion chamber. Only engine repairs will permanently relieve oil wet fouling. IMPORTANT: New engines or recently overhauled engines may wet foul plugs before normal oil control is achieved with proper break-in procedures. Such fouled plugs may be serviced (clean, file and regap) and reinstalled. Figure 3. Wet Fouling 08958 (Oil Deposits) COLD FOULING Dry, black deposits indicate rich fuel mixture or weak ignition. Clogged flame arrestor, flooding carburetor, sticky choke or weak ignition components all are probable causes. If only one or two plugs in set are fouled, however, check for sticking valves or bad ignition leads. After correcting cause, service (clean, file and regap) plugs and reinstall. 08958 Figure 4. Cold Fouling 1C-12 - IMPORTANT iNFC'RM ATI ON/TROUBLESHOOTING 90-95693 485 OVERHEATING Insulator is dull white or gray and appears blistered. Electrodes are eroded and there is an absence of deposits. Check that correct plug heat range is being used. (Sec. 8) Also check over-advanced ignition timing, cooling system malfunction, lean fuel/air mixtures, leaking intake manifold or sticking valves. Replace spark plugs. PRE-IGNITION DAMAGE Pre-ignition damage is caused by excessive high temperatures. Center electrode melts first, followed by ground electrode. Normally, insulators are white but may be dirty if plug has been misfiring. Check for correct plug heat range, advanced ignition timing, lean fuel mixture, incorrect fuel used, malfunctioning cooling system, leaking intake manifold or lack of lubrication. 08957 Figure 5. Overheating HIGH SPEED GLAZING Insulator has yellowish, varnish-like color, indicating that temperatures suddenly have risen, usually during hard, fast acceleration under heavy load. Normal deposits do not get a chance to blow off. Instead, thev melt and form a conductive coating. Replace plugs. If condition re-occurs, use colder heat range plug and service plugs more frequently. Figure 6. 08958 High Speed Glazing SCAVENGER DEPOSITS Powdery white or yellow deposits are built up on shell, insulator and electrodes. This is normal appearance with certain branded fuels. Accumulation on ground electrode and shell areas may be unusually heavy, but may be easily chioped off. Plugs can be serviced (clean, file and regap) and reinstalled. Figure 7. 08958 Scavenger Deposits Figure 8. 08957 Pre-lgnition Damage REVERSED COIL POLARITY Concave erosion of ground electrode is an indication of reversed polarity. Center electrode will show only normal wear. Engine will misfire and idle rough. To correct, reverse primary coil leads. Replace spark plugs. Figure 9. . _ . 08957 Reversed Coil Polarity SPLASHED DEPOSITS Spotted deposits, which sometimes occur after long delayed tune-up, accumulate after a long period of misfiring. When normal combustion temperatures are restored, upon installation of new plugs, deposits loosen from top of piston and head and are thrown against hot insulator. Clean and service plugs and reinstall. Figure 10. 08958 Splashed Deposits 90-95693 485 IMPORTANT INFORMATION/TROUBLESHOOTING - 1A-11 08957 MECHANICA L DAMAG E Mechanical damage to spark plug firing end is caused by foreign object in combustion chamber. Because of valve overlap, small objects can travel from one cylinder to another. Check all cylinders, intake manifold and exhaust manifold to prevent further damage. IMPORTANT: When working on engine, spark plug holes and carburetor throat should be kept covered to prevent foreign objects from entering combustion chamber. Figure 11. Mechanical Damage POOR BOAT PERFORMANCE and/or POOR MANEUVERABILITY SYMPTOM CAUSE 1. Bow too2. Bow too3. Propeller low high ventilating 1.2.3. A. Improper drive unit trim angle (MCM only) B. Improper weight distribution C. Boat is underpowered D. False bottom full of water E. Improperly adjusted trim tabs (after planes) F. Permanent or power hook in boat bottom A. Improper crive unit trim angle (MCM only) B. Dirty boat bottom (marine growth) C. Improper weight distribution D. False bottom full of water E. Improperly adjusted trim tabs (after planes) F. Rocker in boat bottom G. Propeller pitch too great H. Poor running engine A. Propeller plugged up with weeds B. Dirty or rough boat bottom C. Damaged propeller, pitch too small, diametertoosmall (MIE only) D. Keel located too close to propeller or too deep in the water E. Water pick-up or accessories located too close to propeller slip stream F. Hook in boat bottom G. Drive unit installed too high on transom (MCM only) 1C-12 - IMPORTANT iNFC'RM ATI ON/TROUBLESHOOTING 90-95693 485 IMPROPER FULL THROTTLE ENGINE RPM RPM TOO HIGH CAUSE SPECIAL INFORMATION 1. Propeller 2. Boat 3. Operation 4. Engine coupler slipping (MCM only) 1. Damaged, pitch too low, diameter too small (MIE), propeller hub slipping (MCM) 2. Water pick-up or accessories mounted too close to propeller slip stream, keel located too close to propeller and/or too deep in the water (ventilation). Drive installed too high on transom, wrong gear ratio. 3. Unit trimmed out too far (MCM only). RPM TOO LOW CAUSE SPECIAL INFORMATION 1. Propeller 2. Boat 3. Operation 1. Damaged, pitch too great, diameter too great (MIE) 2. Dirty or damaged bottom, permanent or power hook in bottom, false bottom full of water. Drive installed too low on transom, wrong gear ratio. 3. Unit trimmed in too far (MCM only) 90-95693 485 IMPORTANT INFORMATION/TROUBLESHOOTING - 1A-11 ENGINE CRANKS OVER BUT WILL NOT START OR STARTS HARD IMPORTANT INFORMATION stream of fuel coming out of the accelerator pump nozzles if the carburetor has fuel. 1. The first thing that must be determined is which system on 3. Check ignition system operation. Remove coil wire from the engine is causing the problem. To make an engine run it tower on distributor cap. Hold coil wire near ground and takes 3 basic components - fuel, spark (ignition), and com-check for spark while cranking engine over. Repeat procepression. If all three components are present, the engine dure w ith spark plug wires. If there is spark at the spark plug should run. If any one of the three are missing, weak, or wires, remove the spark plugs and make sure the plugs are arriving at the wrong time the engine will not run. correct type and heat range, and not fouled or burned. 2. Determine if there is fuel present by looking down carbure-4. Run a compression check on engine to make sure the engine tor venturi while actuating throttle. There should be a is up to par mechanically. CONVENTIONAL IGNITION (NO SPARK) CAUSE SPECIAL INFORMATION 1. Moisture on ignit on components 1. Distributor cap or spark plug leads arcing 2. Battery, electrica connections, damaged wiring 3. Ignition switch 3. May run in start position and loose spark in the run position 4. Shift interruptor switch (MCM 120-260 only) 5. Shorted tachometer 5. Disconnect tachometer and try again. 6. Ignition timing 6. May crank over hard, backfire, or try to run backwards 7. Faulty ignition resistor wire or bypass wire 8. Ignition points improperly gapped, burned or dirty 9. Spark plugs 9. Fouled, burned, cracked porcelain 10.Spark plug wires 10. Faulty insulation, broken wires 11. Cracked or dirty distributor cap or rotor 12. Coil 13. Condenser THUNDERBOLT IV (HEI) IGNITION (NO SPARK) CAUSE SPECIAL INFORMATION 1. Moisture on ignition components 2. Battery, electrical connections, damaged wiring 3. Ignition switch 4. Shift interruptor switch (MCM 898R-260R) 5. Shorted tachometer 6. Ignition timing 7. Spark plugs 8. Spark plug wires 9. Cracked or dirty distributor cap 10. Faulty ignition components 11. Engine synchronizer (if equipped) hooked up in series on purple ignition w re (dual engines only) I. Distributor cao or spark plug wires arcing 5. Disconnect tachometer and try again 7. Fouled, burned, cracked porcelain 8. Faulty insulation, broken wires 10. Refer to page 1C-7 to check components II. Synchronizers must be hooked up directly at coil terminal (parallel circuit) 1C-12- IMPORTANT iNFC'RM ATI ON/TROUBLESHOOTING 90-95693 485 THUNDERBOLT IV (HEI) IGNITION TEST 90-95693 485 IMPORTANT INFORMATION/TROUBLESHOOTING- 1A-11 FUEL SYSTEM RICH CAUSE SPECIAL INFORMATION 1. Warm engine carburetor percolation 2. Clogged flame arrestor 3. Automatic choke not opening 4. Float adjustment 5. Float leaks or is saturated with fuel 6. Needle and seat leaking 7. Carburetor gaskets leaking 8. Excessive fuel pump pressure 9. Cracked or porous carburetor body 1. Fuel boils out of float bowl when shut off and warm. Flood intake manifold. 8. Unseats needle and seat FUEL SYSTEM LEAN CAUSE SPECIAL INFORMATION 1. Empty fuel tank 2. Fuel shut off valve closed (if equipped) 3. Anti-siphon valve stuck closed (if equipped) 4. Vapor lock 5. Automatic choke 6. Fuel tank vent plugged 7. Air leak on suction side of fuel system 8. Plugged or pinched fuel line 9. Fuel pump 4. Engine will not start after warm engine shut down 5. Stuck open, wrong adjustment 6. Engine will start initially. After a short time of running engine will stall and will not restart for a period of time. Can verify it is a vent problem by running engine with fuel tank filler cap loose. Filler cap will act as a vent. 7. Sucks air into fuel system reducing fuel volume 9. Low pump pressure MISCELLANEOUS CAUSE SPECIAL INFORMATION 1. Low grade or stale fuel 2. Water in fuel 3. Vacuum leak 4. Low compression 5. Valve timing incorrect 4. Worn valves, rings, cylinder, or head gasket 5. Timing chain or gears jumped or improperly installed 1C-12- IMPORTANT iNFC'RM ATI ON/TROUBLESHOOTING 90-95693 485 ENGINE WILL NOT CRANK OVER CAUSE SPECIAL INFORMATION 1. Control lever not in neutral position 2. Battery cha'ge low, damaged wiring, loose electrical connections 3. Blown fuse at starter motor (if so equippec) 4. Circuit breaker tripped 5. Ignition switch 6. Slave solenoid (GM engines only) 7. Faulty neutral start safety switch 8. Starter solenoid 9. Starter motor 3. Early models with red wire going to fuse on starterterminal only 7. Open circuit CHARGING SYSTEM INOPERATIVE CAUSE SPECIAL INFORMATION 1. Loose or broken drive belt 2. Engine RPM too low on initial start 3. Loose or corroded electrical connections 4. Faulty ammeter or battery gauge 5. Battery will not accept charge 6. Faulty alternator or regulator 7. Failed fuse (if so equipped) 8. Refer to "Section 3, Part C" for complete troubleshooting procedures. 2. Rev engine to 1500 RPM 4. Best way to test is to replace gauge 5. Low electrolyte, failed battery 7. Fuse located on starter terminal stud. Orange output wire from alternator connects to fuse. NOISY ALTERNATOR CAUSE SPECIAL INFORMATION 1. Loose mounting bolts 2. Drive belt 3. Loose drive pulley 4. Worn or dirty bearings 5. Faulty diode trio or stator 2. Worn, frayed, loose 90-95693 485 IMPORTANT INFORMATION/TROUBLESHOOTING - 1A-11 INSTRUMENTATION MALFUNCTION CAUSE SPECIAL INFORMATION 1. Faulty wiring, loose or corroded terminals 2. Bad key switch 3. Faulty gauge 4. Faulty sender 2. Test as outlined in "Section 3, Part D" 3. Test as outlined in "Section 3, Part D" 4. Test as outlined in "Section 3, Part D" RADIO NOISE CAUSE SPECIAL INFORMATION 1. A "popping" noise that will increase with engine RPM. Noise will stop as soon as engine is turned off. 2. "High pitched whine" in the radio 3. A "hissing or crackling" noise when instruments are jarred with ignition on 4. Varying unexplained noises 1. Ignition System wrong spark plugs, cracked distributor cap, cracked coil tower, leaking spark plug wires, moisture on ignition components. 2. Alternator - poor brush contact on the slip rings 3. Instrumentation loose connections, or antennae wire routed too close to instruments 4. Accessories - bilge pump, bilge blower, fish finder, depth locator, cabin heater motor, etc. Disconnect one at a time until noise disappears. POOR FUEL ECONOMY CAUSE SPECIAL INFORMATION 1. Fuel leaks 2. Operator habits 3. Engine laboring 4. Clogged flame arrestor 5. Engine compartments sealed too tight 6. Boat bottom 7. Carburetor 8. Improper fuel 9. Crankcase ventilation system not working 10. Engine needs tune-up 11. Engine running too cold or too hot 12. Plugged or restricted exhaust 13. Engine 2. Prolonged idling, slow acceleration, failure to cut back on throttle once boat is on plane, boat overloaded, uneven weight distribution 3. Bent, damaged, wrong propeller. Water test boat for proper operating RPM at WOT. 6. Dirty (marine growth), hook, rocker 7. Idle mixture settings, accelerator pump adjustment, linkage binding, choke adjustment, carburetor flooding over, main fuel jets 13. Low on compression 1C-12 - IMPORTANT iNFC'RM ATI ON/TROUBLESHOOTING 90-95693 485 CARBURETOR MALFUNCTIONS SYMPTOM CAUSE 1. Flooding 2. Rough idle 3. Hesitation or acceleration flatness 4. Engine surges 5. Low top speed or lack of power 6. Poor cold engine operation 7. Engine stalls 8. Hard starting 1. A. Needle and seat B. Float adjustment C. Saturated float D. Gaskets leaking E. Cracked fuel bowl F. Fuel percolation G. Automatic choke 2. A. Idle RPM too low B. Idle mixture screws C. Idle passages dirty D. Throttle valves not closing E. Engine flooding F. Vacuum leak G. Throttle body heat passages plugged 3. A. Accelerator pump B. Leaking gaskets C. Automatic choke D. Power piston or power valve E. Throttle valves F. Throttle body heat passages plugged G. Main metering jets H. Float adjustment I. Secondary air valve wind-up 4. A. Main metering jets B. Leaking gaskets C. Float adjustment D. Saturated float E. Power piston or valve F. Throttle valves 5. A. Power piston or valve B. Float adjustment C. Main metering jets D. Leaking gaskets 6. A. Idle RPM too low B. Idle mixture screws C. Throttle valves D. Automatic choke E. Engine flooding 7. A. Idle RPM too low B. Idle mixture screws C. Engine flooding D. Automatic choke E. Dirt in carburetor F. Accelerator pump G. Leaking gaskets 8. Refer to page 1C-6 90-95693 485 IMPORTANT INFORMATION/TROUBLESHOOTING - 1A-11 ENGINE RUNS POORLY AT IDLE CAUSE SPECIAL INFORMATION 1. Clogged flame arrestor 2. Improper idle fuel mixture adjustment 3. Moisture on ignition components 3. Cap or spark plug wires arcing 4. Water in fuel 5. Low grade or stale fuel 6. Incorrect ignition timing 7. Automatic choke 8. Spark plugs 8. Fouled, burned, cracked porcelain 9. Incorrect point gap, burned or pitted points 10. Spark plug wires 10. Insulation break down, wires broken 11. Defective coil or condenser 12. Cracked or dirty distributor cap 13. Incorrect float level 14. Dirty carburetor 15. Vacuum leak 15. Leak at manifold or carburetor base 16. Incorrect fuel pump pressure 16. Too low, can't supply the carburetor Too high, unseats the needle and seat 17. Low compression 17. Also check for blown head gasket 18. Loose or worn distributor 18. Timing and/or dwell changes 19. Water leaking into cylinders 19. Head gasket, exhaust manifold, cracked head or valve seat 20. Loose or broken engine mounts ENGINE ACCELERATION IS POOR CAUSE SPECIAL INFORMATION 1. Also refer to "Poor Boat Performance", page 1C-4 2. Idle mixture screws 3. Air valve spring out of adjustment 3. Rochester 4 barrel carb only 4. Incorrect ignition timing 5. Incorrect distributor or amplifier advance curve 5. Refer to "Section 3, Part B" 6. Accelerator pump 6. Check for stream of raw fuel from accelerator pump discharge nozzle, when opening throttle with engine shut off 7. Cracked or dirty distributor cap or rotor 8. Vacuum leak 8. Manifold or carburetor base 9. Spark plugs 9. Fouled, burned, wrong heat range, cracked porcelain 10. Incorrect point gap, dirty or burned points 11. Float adjustment 12. Dirty carburetor 13. Low compression 1C-12 - IMPORTANT iNFC'RM ATI ON/TROUBLESHOOTING 90-95693 485 ENGINE RUNS POORLY AT HIGH RPM CAUSE SPECIAL INFORMATION 1. Also refer to "Poor Boat Performance", page 1C-4 2. Crankcase over-filled with oil 2. Check oil level with boat at rest in the water. Refer to "Section 1. Part B" 3. Anti-siphon valve (if equipped) 4. Plugged fuel tank vent 3. Restricting fuel supply 5. Fuel supply 6. Ignition timing 5. Refer to page 1 C-11 7. Low grade of fuel or water in the fuel 8. Spark plugs 8. Fouled, burned, cracked, porcelain, heat range 9. Spark plug wires 9. Poor insulation, broken wires 10. Distributor cap or rotor 10. Dirty or cracked 11. Coil 12. Distributor 12. Points, condenser, worn cam, excessive play in shaft 13. Engine overheating 13. Refer to page 1C-19 or 1C-20 14. Low compression 14. Worn valves, rings, cylinders, etc. 15. Restricted exhaust TROUBLESHOOTING WITH VACUUM GAUGE READING CAUSE 1. Steady reading betweeen 15-21 inches at idle RPM 2. Extremely low reading, but steady at idle RPM 3. Fluctuates between high and low at idle RPM 4. Fluctuates 4 or 5 inches very slowly at idle RPM 5. Fluctuates rapidly at idle, steadies as RPM is increased 6. Continuously fluctuates between low and normal reading at regular intervals at idle RPM 1. Normal 2. Vacuum leak, incorrect timing, underpowered boat, faulty boat bottom 3. Blown head gasket between 2 adjacent cy'inders 4. Carburetor needs adjustment, spark plug gap too narrow, valves are sticking 5. Valve guides are worn 6. Burned or leaking valve 90-95693 485 IMPORTANT INFORMATION/TROUBLESHOOTING - 1A-11 ENGINE NOISE IMPORTANT INFORMATION No definite rule or test will positively determine source of engine noise; therefore, the following information should be used only as a general guide to engine noise diagnosis. 1. Use a timing light to determine if noise is timed with engine speed or one-half engine speed. Noises timed with engine speed, are related to crankshaft, rods, pistons, piston pins, and flywheel. Noises timed to one-half engine speed are valve train related. 2. The use of a stethoscope can aid in locating a noise source; however, because noise will travel to other metal parts not involved in the problem, caution must be exercised. 3. If you believe noise is confined to one particular cylinder, ground spark plug leads, one at a time. If noise lessens noticeably or disappears, it is isolated to that particular cylinder. 4. Try to isolate the noise to location in engine. Front to back. top to bottom. This can help determine which components are at fault. 5. Sometimes noises can be caused by moving parts coming in contact with other components. Examples of this would be, loose flywheel or coupler, exhaust flappers rattling against exhaust pipe, crankshaft striking (pan. pan baffle, or dipstick tube), rocker arm striking valve cover, and loose flywheel cover. In many cases if this is found to be the problem a complete engine tear down is not necessary. 6. When noise is isolated to a certain area and component, removal and inspection will be required. Refer to proper sections of service manual for information required for service. 7. If noise cannot be distinguished between engine or drive unit, remove drive from boat. Run a water supply directly to engine, then run engine without the drive to determine if noise is still there. VALVE COVER AREA LOCATION POSSIBLE CAUSES 1. Valve cover area, timed to one-half engine speed, noise could be confined to one cylinder or may be found in any multitude of cylinders. 1. A. Rocker arm striking valve cover B. Rocker arm out of adjustment C. Worn rocker arm D. Bent push rod E. Collapsed lifter CYLINDER AREA LOCATION POSSIBLE CAUSES 1. Cylinder area, may be confined to one cylinder or found in more than one cylinder, timed to engine speed 1. A. Sticking valve B. Carbon build up C. Connecting rod installed wrong D. Bent connecting rod E. Piston F. Piston rings G. Piston pin H. Cylinder worn CAMSHAFT AREA LOCATION POSSIBLE CAUSES 1. Camshaft area, front of engine, timed to one-half engine speed 2. Camshaft area, center of engine, timed to one-half engine speed 3. Camshaft area, rear of engine, timed to one-half engine speed 4. Camshaft area, throughout engine, timed to one-half engine speed 1. A. Camshaft timing sprocket or gear B. Timing chain C. Fuel pump (V-8 only), Distributor Gear (4 & 6 cylinder only) D. Valve lifter E. Cam bearings 2. A. Fuel pump (4 & 6 cylinder only) B. Valve lifter C. Cam bearings 3. A. Distributor gear (V-8 only) B. Valve lifter C. Cam bearings 4. A. Loss of oil pressure B. Valve lifters C. Cam bearings 1C-12 - IMPORTANT iNFC'RM ATI ON/TROUBLESHOOTING 90-95693 485 CRANKSHAFT AREA LOCATION POSSIBLE CAUSES 1. Crankshaft area, front of engine, timed to engine speed 2. Crankshaft area, center of engine, timed to engine speed 3. Crankshaft area, rear of engine, timed to engine speed 4. Crankshaft area, throughout engine, timed to engine speed 1.2.3.4. A. Crankshaft timing sprocket or gear B. Timing chain C. Main bearing D. Rod bearing A. Crankshaft striking pan or pan baffle B. Main bearing C. Rod bea'ing A. Loose flywheel cover B. Loose coupler C. Loose flywheel D. Drive plate E. Main bearing F. Rod bearing A. Loss of oil pressure B. Main bearings C. Rod bearings MISCELLANEOUS NOISE POSSIBLE CAUSE 1. Engine spark knock 2. Popping through carburetor 3. Hissing 4. Whistle 5. Sparks jumping 6. Squeaks or squeals 7. Rattling in exhaust pipe area 1. A. Advanced timing B. Low octane fuel C. Engine rjnning hot D. Carbon deposits in engine 2. A. Wrong ignition timing B. Carburetor set up too lean C. Faulty accelerator pump D. Vacuum leak E. Valve adjustment F. Valve timing G. Burned or stuck valve 3. A. Vacuum leak B. Fuel pump (hissing in sight tube) C. Leaking exhaust (manifolds or pipes) D. Loose cylinder heads E. Blown head gasket 4. A. Vacuum leak B. Dry or tight bearing in an accessory 5. A. Leaking high tension lead B. Cracked coil tower C. Cracked distributor cap 6. A. Drive belt slipping B. Dry or tight bearing in an accessory C. Parts rubbing together 7. A. Exhaust shutters /—^ 90-95693 485 IMPORTANT INFORMATION/TROUBLESHOOTING - 1A-11 OIL PRESSURE NOTICE Refer to "Section 1, Part B" for minimum oil pressure readings. IMPORTANT INFORMATION 1. Measuring oil pressure 2. Check engine oil level with boat at rest in the water 3. Oil level in crankcase above full mark 4. Oil level in crankcase below add mark 5. Change in oil pressure 6. Low engine oil pressure at idle 7. Low engine oil pressure at idle after running at a high RPM 8. Boats with dual engines 9. Boats with dual stations 1. Use a good automotive oil pressure test gauge. Do not rely on the oil pressure gauge in the boat. 2. Oil level should be between the add and full marks. DO NOT overfill. 3. May cause loss of engine RPM, oil pressure gauge flucuation, drop in oil pressure, and hydraulic valve lifter noise at high RPM 4. Low oil pressure, oil pressure gauge flucuation, internal engine noise and/or damage 5. This may be a normal condition. Oil pressure may read high in the cooler times of the day, and wt-en engine is not up to operating temperature. As the air temperature warms up and engine is running at normal operating temperature, it is normal for oil pressure to drop off slightly. 6. With modern engines and engine oils, low oil pressure readings a: idle does not necessarily mean there is a problem. If valve lifters do not "clatter" (at idle), there is a sufficient volume of oil to lubricate all internal moving parts properly. The reason for the drop in oil pressure is that engine heat causes an expansion of tne internal tolerances in the engine and also the oil will th n out somewhat from heat. 7. Refer to "No. 5 and 6" preceding 8. It is not uncommon to see different oil pressure readings between tne two engines, as long as both engines fall within specifications. Differences in oil pressure can be attributed to differences in engine tolerances, gauges, wiring, senders, etc. 9. Refer to "No. 8" preceding 1C-12 - IMPORTANT iNFC'RM ATI ON/TROUBLESHOOTING 90-95693 485 LOW OIL PRESSURE NOTICE Refer to "Section 1, Part B" for minimum oil pressure readings. CAUSE SPECIAL INFORMATION 1. Low oil level in crankcase 2. Defective oil pressure gauge and/or sender 3. Thin or diluted oil 4. Oil pump 5. Oil leak, can be internal or external 6. Excessive bearing clearance 2. Verify reading with an automotive test gauge. Refer to "Section 3, Part D" for instrument testing. 3. Oil broken down, contains water or gas, wrong viscosity, engine running too hot or too cold, excessive idling in cold water (condensation) 4. Relief valve stuck open, pick-up tube restricted, worn parts in oil pump, air leak on suction side of oil Dump or pick-up tube 5. Oil passage plugs leaking, cracked or porous cylinder block 6. Cam bearings, main bearings, rod bearings HIGH OIL PRESSURE CAUSE SPECIAL INFORMATION 1. Oil too thick 2. Defective oil pressure gauge and/or sender 3. Clogged or restricted oil passage 4. Oil pump relief valve stuck closed 1. Wrong viscosity, oil full of sludge or tar 2. Verify with an automotive test gauge IMPORTANT: Oil pressure slightly higher than normal does not always mean there is a problem. Tolerance stack- up in the engine, oil viscosity, and weather conditions could cause high oil pressure. EXCESSIVE OIL CONSUMPTION CAUSE SPECIAL INFORMATION 1. Normal consumption 2. Oil leaks 3. Oil too thin 4. Oil level too high 5. Drain holes ir cylinder head plugged 6. Defective valve seals 7. Intake manifold gasket leaking 8. Worn valve stems or valve guides 9. Defective oil cooler (if so equipped) 10. Defective piston rings 11. Defective cylinders 12. Excessive bearing clearance 1. One quart of oil consumed in 5-15 hours of operation at WOT (especially in a new or rebuilt engine) is normal 2. Clean bilge, run engine with clean white paper on bilge floor, locate oil leak(s) 3. Oil diluted or wrong viscosity 5. Oil will flocd valve guides 7. Mercury Marine and GM V-8 engines only 9. Crack in cooler tubes 10. Glazed, scuffed, worn, stuck, improperly installed, ring grooves wcrn, improper break-in, wrong end gap 11. Out of round, scored, tapered, glazed, excessive piston to cylinder clearance, cracked piston 90-95693 485 IMPORTANT INFORMATION/TROUBLESHOOTING - 1C-17 WATER IN ENGINE IMPORTANT INFORMATION IMPORTANT: The first thing that must be determined is where in the engine the water is located. This information can be of great help when trying to determine where the water came from and how it got into the engine. The three most common problems are "water on top of pistons, water in crankcase oil, water in crankcase oil and on top of pistons". The first step, after the water is located, is to remove all the water from the engine by removing all spark plugs and pump cylinders out by cranking engine over. .Next change oil and filter. N ow start engine and see if the problem can be duplicated. If problem can be duplicated, more than likely it is a mechanical WATER ON TOP problem of some sort. If the problem cannot be duplicated the problem is either an operator error or a problem that exists only under certain environmental conditions. If water is contained in cylinder(s) only, it usually has entered through the intake system, exhaust system, or head gasket. If the water is contained in crankcase only, it usually is caused bv a cracked or porous block, a flooded bilge, or condensation. If the water is located in both the cylinder(s) and the crankcase, it usuallv is caused by water in the cylinders getting past the rings and valves, or complete submersion. Checking for rust in the intake manifold or exhaust manifolds is a good idea. Rust in these areas will give clues if the water entered through these areas. OF PISTONS CAUSE SPECIAL INFORMATION 1. Operator shut engine off at high RPM 2. Engine "diesels" or trys to run backwards 3. Rain water running into flame arrestor 4. Spark plug misfiring 5. Backwash through the exhaust system 6. Improper engine or exhaust hose installation 7. Cracked exhaust manifold 8. Improper manifold to elbow gasket installation 9. Loose cylinder head bolts 10. Blown cylinder head gasket 11. Cracked valve seat 12. Porous or cracked casting 2. Engine out of tune, poor fuel, high idle RPM, timing set too high 3. Hatch cover 4. Improper combustion causes moisture in the air to accumulate in tne cylinder 6. Refer to "Section 5, Part C" for exhaust specifications 10. Check for warped cylinder head or cylinder block 12. Check cylinder heads, cylinder block, and intake manifold (Mercury Marine and GM V-8 engines) WATER IN CRANKCASE OIL CAUSE SYMPTOM 1 Water in boat bilge 2. Water seeping past piston rings or valves 3. Engine running cold 4. Intake manifold leaking near a water passage 5. Cracked or porous casting 1. Boat has been submerged or bilge water was high enough to run in throjgh dipstick tube. 2. Refer to "Water On Top Of Pistons" 3. Defective thermostat, missing thermostat, prolonged idling in cold water 5. Check cylinder head, cylinder block, and intake manifold on (488 and GM V-8 engines) 90-95693 485 1C-18 - IMPORTANT INFORMATION/TROUBLESHOOTING ENGINE OVERHEATS (MECHANICAL) CAUSE SPECIAL INFORMATION 1. Engine RPM below recommendations at WOT (engine laboring) 2. Wrong ignition timing 3. Sticking distributor advance weights 4. Spark plug wires crossed (wrong firing order) 5. Lean fuel mixture 6. Wrong heat range spark plugs 7. Exhaust restrict on 8. Valve timing off 9. Blown head gasket(s) 10. Insufficient lubrication to moving parts of engine 1. Damage or wrong propeller, growth on boat bottom, false bottom full of water 2. Timing too far advanced 5. Refer to page 1 C-11 8. Jumped timing chain and/or gears or improperly installed 9. A blown head gasket(s) normally cannot be detected by a compression check. Normally the engine will run at normal temperature at low RPM, but will overheat at speeds above 3000 RPM. GM engines that are seawater cooled: Using a clear plastic hose, look for air bubbles between seawater pump and engine. If there are no bubbles present, install clear plastic hose between thermostat housing and manifold(s). If air bubbles are present at a higher RPM it is a good indication there is a blown head gasket. 470/485/488: Refer to "Section 7, Part B". All other models with closed cooling: Refer to "Section 7, Part B". 10. Defective oil pump, plugged oil passage, low oil level 90-95693 485 IMPORTANT INFORMATION/TROUBLESHOOTING - 1A-11 ENGINE OVERHEATS (COOLING SYSTEM) CAUSE SPECIAL INFORMATION IMPORTANT: The first step is to verify if the engine is actually overheating or the temperature gauge or sender is faulty. 1. Loose or broken drive belt 2. Seawater shut-oft valve partially or fully closed (if equipped) 3. Clogged or improperly installed sea strainer 4. Loose hose connections between seawater pick-up and seawater pump inlet. (Models with belt driven seawater pump only) 5. Seawater inlet hose kinked or collapsed 6. Improper installation of the hot water heater (if equipped) 7. Seawater pick-up clogged 8. Obstruction on boat bottom causing water turbulence 9. Defective thermostat 10. Exhaust elbow water outlet holes plugged 11. Insufficient seawater pump operation 12. Obstruction in cooling system such as casting flash, sand, rust, salt, etc. 13. Engine circulating pump defective 14. Also refer to "Engine Overheats (Mechanical)" IMPORTANT: In addition to previous checks, make the following checksif engine is equipped with closed cooling. 15. Low coolant level 16. Anti-freeze not mixed properly 17. Heat exchanger cores plugged 18. Water hoses reversed at the water distribution block 19. For further testing of the closed cooling system IMPORTANT: Best way to test gauge or sender is to replace them. 2. Refer to "Section 7, Part A" 3. Refer to "Section 7, Part A" 4. Pump will suck air. Pump may fail to prime or will force air bubbles into cooling system. 6. 470/485/488 refer to "Section 7, Part B", all other models refer to "Section 7. Part A" 8. Obstruction will be in front of seawater pick-up, causing air bubbles tc be forced into cooling system. 11. Worn pump impeller 12. Refer to water flow diagram for engine being serviced 16. Anti-freeze should be mixed 50/50 or maximum 60/40 (60% anti-freeze. 40% water) 18. Refer to water flow diagrams "Section 7, Part C" 19.470/485/488 - refer to "Section 7, Part B" All other models - refer to "Section 7, Part C" 1C-12 - IMPORTANT iNFC'RM ATI ON/TROUBLESHOOTING 90-95693 485 INSUFFICIENT WATER FLOW FROM MC-I STERN DRIVE UNIT SEAWATER PICKUP PUMP CAUSE SPECIAL INFORMATION 1. Seawater shut-oft valve partially or fully closed (if equipped) 2. Water pickups clogged with foreign material 3. Kinked or broken bell housing-to-gimbal housing water tube hose 4. Corroded thru gimbal housing water tube 5. Water pickup inserts warped. (Engine will overheat while boat is underway only.) 6. Damaged gear housing or accessories improperly installed on boat bottom or transom (speedometer pickup, depth sounder transducer, etc.). Substantial amount of barnacles or other marine growth on gear housing or boat bottom. (Engine will overheat while underway only.) 7. Stern drive installed too high on transom o' drive unit trimmed too far out allowing air to be drawn into pump. (Engine will overheat while underway only.) 8. Bell housing-tc-drive shaft housing "O" ring missing or damaged 9. Faulty seawater pickup pump 10. Seawater pickup pump water tube corroded thru 11. Drive shaft housing water pocket cover cracked 12. Broken-off impeller blade or other obstruction in water passages (usually lodges in drive shaft housing water pocket cover or cross-drilled water passage). 13. Water passage in drive shaft housing improperly drilled 5. Pickup inserts must not protrude above gear housing surface or inserts will create an irregular or turbulent water flow over the water pickup holes. This condition also can be identified by cavitation burn (pitting, erosion) on the gear housing in the area aft of the water pickup inserts. 6. An object oran irregularity on boatorgearhousing inarea close to water pickups could create turbulence in water flow going to water pickups. This could aerate the water flow and cause engine to overheat. 7. Contact boat company if stern drive is installed too high. Instruct operator on proper trimming technique if unit is trimmed out too far. 12. To check cross-drilled water passage in drive shaft housing, remove welch plug and pipe plug located under decal on starboard side of housing. Drive unit must be shifted into reverse :o remove pipe plug. INSUFFICIENT WATER FLOW FROM BELT DRIVEN SEAWATER PICKUP PUMP CAUSE SPECIAL INFORMATION 1. Drive belt 2. Seawater shut-cff valve partially or fully closec 3. Clogged or improperly installed sea strainer 4. Loose hose connections between seawater pickup and seawater pump inlet 5. Seawater inlet hose kinked or plugged 6. Seawater pickup clogged 7. Obstruction on boat bottom causing water turbulence 8. Faulty seawater pump 1. Loose or broken 2. Refer to "Section 7, Part A" 3. Refer to "Section 7, Part A" 4. Pump will suck air, pump may fail to prime or will force air bubbles into cooling system 7. Obstruction will be in front of seawater pickup, causing air bubbles to be forced into cooling system 90-95693 485 IMPORTANT INFORMATION/TROUBLESHOOTING - 1A-11 BORG-WARNER TRANSMISSION MALFUNCTIONS NEUTRAL SYMPTOM CAUSE 1. Output shaft drags excessively in forward rotation 2. Output shaft dracs excessively in reverse rotation 1. A. Shift linkage improperly adjusted B. Forward clutch improperly assembled C. Damaged or broken belleville clutch springs D. Damaged forward clutch plate(s) 2. A. Shift linkage improperly adjusted B. Reverse clutch plate improperly assembled C. Damaged reverse clutch plate(s) D. Damaged or broken clutch springs E Planetary gear failure FORWARD GEAR SYMPTOM CAUSE 1. Low fluid pressure 2. Forward clutch engages improperly 3. Forward clutch plate slips (does not fully engaged) 4. Reduction unit failure (inboard only) 1. A. Dirty fluid screen B. Low fluid level C. Faulty regulator valve D. Worn fluid pump 2. A. Shift linkage improperly adjusted B. Sheared forward clutch hub drive key C. Worn or misaligned bushings in transmission case D. Worn or damaged clutch piston E. Oil seals and/or clutch sealing rings F. Clutch improperly assembled G. Damaged or broken belleville clutch spring H. Worn or damaged clutch plate(s) 3. A Shift linkage improperly adjusted B. Clutch improperly assembled C. Damaged or broken belleville clutch spring D. Worn or damaged clutch plates 4. A. Planetary gear failure REVERSE GEAR SYMPTOM CAUSE 1. Low fluid pressure 2. Reverse clutch engages improperly 3. Reverse clutch s ips (does not engage fully) 4. Reverse gear set failure 5. Reduction gear failure 1.2.3.4.5. A. Dirty fluid screen B. Low fluid level C. Faulty regulator valve D. Worn fluid pump A. Shift linkage improperly adjusted B. Worn or damaged clutch piston oil seals C. Reverse clutch improperly assembled D. Worn or damaged clutch plate(s) E. Damaged or broken clutch springs A. Shift linkage improperly adjusted B. Reverse clutch improperly assembled C. Worn or camaged reverse clutch plate(s) D. Damaged or broken clutch springs A. Planetary gear failure A. Planetary gear failure 1C-12 - IMPORTANT iNFC'RM ATI ON/TROUBLESHOOTING 90-95693 485 ALL GEARS SYMPTOM CAUSE 1. No fluid pressure 2. Low fluid pressure 3. High fluid temperature 4. Failure of reduction gear 1. No fluid, pump improperly installed for engine rotation, fluid pump drive key sheared 2. Dirty fluid screen, low fluid level, faulty regulator valve, worn fluid pump 3. Water in transmission fluid from a damaged fluid cooler, low fluid level, high fluid level, low water supply to fluid cooler, plugged fluid cooler, planetary gear failure 4. Planetary gear failure LEAKS SYMPTOM CAUSE 1. Fluid leaks at pump 2. Fluid on exterior of transmission 3. Fluid leaks at rear bearing retainer 4. Water in transmission fluid 1. Loose bolts, damaged gasket, damaged oil seal, foreign material on mating surfaces. 2. Loose bolts or fluid line fittings, fluid filler cap leaks, damage "0" ring on control valve, damaged gasket, porous transmission housing, foreign material on mating surfaces 3. Loose bolts, damaged gasket, damaged oil seal, foreign material on mating surfaces 4. Damaged fluid cooler MISCELLANEOUS SYMPTOM CAUSE 1. Forward gear noise 2. Reverse gear noise 3. Pump noise 4. Shifts hard 5. High fluid pressure 1. Output sha't nut not torqued, nick on gears 2. Outputshaft nut nottorqued, nickongears. planetary gear failure 3. Low fluid level, worn fluid pump, nicks on gears 4. Regulator valve stuck, shift linkage improperly adjusted, control lever and poppet ball corroded, shift linkage interference, damaged control valve "0" ring 5. Regulator valve stuck, wrong fluid used in transmission, cold fluid 90-95693 485 IMPORTANT INFORMATION/TROUBLESHOOTING — 1C-23 MERCURY MARINE TRANSMISSION MALFUNCTIONS NEUTRAL SYMPTOM CAUSE 1. Output shaft drags excessively in forward rotation 2. Output shaft drags excessively in reverse rotation 1. Electric Shift Models Electric control box and/or shift motor not working properly Manual Shift Models Control box not working or cables not adjusted properly All Models - Fcrward clutch pack not assembled properly, damaged forward clutch return spring, damaged clutch plates 2. Reverse clutch lever not free, incorrect reverse band adjustment, improperly assembled reverse clutch band assembly FORWARD GEAR SYMPTOM CAUSE 1. Low fluid pressure 2. Forward clutch engages improperly 3. Forward clutch slips (does not fully engage) 1. Low fluid level, dirty fluid screen, worn or misaligned output sleeve, damaged teflon seal rings, faulty fluid pump, fluid leaks, faulty relief valve 2. Electric Shift Models Electric control box and/or shift motor not working properly Manual Shift Models Control box not working or cables not adjusted properly All Models - Control valve assembled incorrectly, worn or misaligned output sleeve, damaged clutch piston oil seals, damaged teflcn seal rings, forward clutch pack improperly assembled, damaged forward clutch return spring, worn or damaged clutch plates, broken piston housing 3. Electric Shift Models - Control box and/or shift motor not working properly Manual Shift Models - Control box not working or cables out of adjustment All Models Forward clutch pack improperly assembled, damaged forward clutch return spring, damaged clutch plates REVERSE GEAR SYMPTOM CAUSE 1. Low fluid pressure 2. Reverse clutch engages improperly 1. Low fluid level, dirty fluid screen, faulty fluid pump, fluid leak, faulty relief valve 2. Electric Shift Models Electric control box and/or shift motor not working properly Manual Shift Models - Control box not working or cables not adjusted properly All Models Incorrect reverse band adjustment, control valve assembled incorrectly, fluid leak, damaged reverse band, improperly assembled reverse clutch band assembly, planetary gear failure 1C-12 - IMPORTANT iNFC'RM ATI ON/TROUBLESHOOTING 90-95693 485 ALL GEARS SYMPTOM CAUSE 1. No fluid pressure 2. Low fluid pressure 3. High fluid temperature 4. Does not shift 1. No fluid, fluid level low, broken pump, sheared pump drive key, faulty relief valve 2. Low fluid level, dirty fluid screen, worn fluid pump, faulty relief valve 3. Fluid level low, dirty or plugged fluid cooler or fluid line, restricted water flow to fluid cooler 4. Electric Shift Models - Control box and/or shift motor not working properly, loose electrical connections, broken wires Manual Shift Models Control box not working properly All Models - Control valve not assembled correctly LEAKS SYMPTOM CAUSE 1. Fluid leaks at control valve 2. Fluid leaks at pump 3. Fluid leaks at output housing 4. Fluid on exterior of transmission 5. Water in transmission fluid 1. Fluid passage plugs leaking, loose bolts, damaged "0" rings, damaged gasket or foreign material on mating surface, porous control valve housing 2. Damaged "0" rings, loose bolts, damaged oil seal, foreign material or mating surface, relief valve or fluid discharge passage plug leak, porous casting 3. Loose bolts, damage "0 " ring, damaged oil seal, porous housing, foreign material on mating surfaces, fluid passage ball plug not properly seated 4. Dipstick tube leaks, loose bolts, damaged gasket or foreign material on mating surfaces, damaged "0" rings, porous housing, damaged oil seal, fluid passage plugs leaking 5. Damaged fluid cooler MISCELLANEOUS SYMPTOM CAUSE 1. Fluid foaming 2. Gear noise in reverse 3. Pump noise 4. Flywheel drive plate noise or failure 5. High fluid pressure 6. Smoking 1. High fluid level, air in fluid, dirty fluid screen 2. Nicks on gears, planetary gear failure 3. Low fluid level, dirty fluid screen 4. Flywheel drive plate assembly damaged 5. Wrong fluid, cold fluid, faulty relief valve 6. Low fluid level, transmission not shifting properly, reverse clutch lever not free, high rotational speec in reverse 90-95693 485 IMPORTANT INFORMATION/TROUBLESHOOTING — 1C-23 POWER STEERING POOR, ERRATIC, OR NO ASSIST CAUSE SPECIAL INFORMATION 1. Drive belt I. Broken or out of adjustment 2. Low fluid level 3. Air in system 3. Air leak in lines, pump, or air from installation. Refer to "Section 9" for bleeding procedure. 4. Leaking hoses 4. Refer to "Section 9" for bleeding procedure 5. Steering cable and/or steering helm 5. Cable or helm partially froze from corrosion or rust, cable over lubricated, improper cable installation 6. Binding in stern drive unit 6. Refer to appropriate "Stern Drive Service Manual" 7. Restriction in hydraulic hoses 7. Causes a loss of pressure 8. Control valve not positioned properly, not balanced properly, or the mounting nut is loose 9. Mounting bracket adjusting screw loose or mo jnting tube is loose 10. Faulty pump 10. Flow control valve may be sticking 11. Worn piston ring or scored housing bore in cylinder II. Causes loss of pressure 12. Leaking valve body or loose fitting spool NOISY PUMP CAUSE SPECIAL INFORMATION 1. Drive belt 2. Low fluid level 3. Air in fluid 4. Faulty pump 5. Restricted fluid passages 6. Stop nut adjusted improperly 7. Steering cables installed that do not meet BIA standards 1. Check tension 3. Air leak in lines, pump, or air from installation. Refer to "Section 9" for bleeding procedure. 4. Use stethoscope to listen for noise in the pump 5. Kinks or debris in hoses or debris in passages 6. Refer to appropriate "Stern Drive Service Manual" 7. Refer to appropriate "Stern Drive Service Manual" FLUID LEAKS CAUSE SPECIAL INFORMATION 1. Loose hose connections 2. Damaged hose 3. Fluid leaking from top of pump 4. Cylinder piston rod seal 5. Faulty seals in valve 6. Faulty seals or "0 " rings in pump 7. Cracked or porous metal parts 1. Refer to "Section 9" for bleeding procedure 3. System overfilled, fluid contains water, fluid has air in it 1C-12 - IMPORTANT iNFC'RM ATI ON/TROUBLESHOOTING 90-95693 485 SECTION 2 - REMOVAL, INSTALLATION and ALIGNMENT PART A - MCM 120-140-165 INDEX Page Torque Specifications 2A-1 Tools/Lubricants 2A-1 Removal 2A-1 Installation 2A-2 Alignment 2A-5 Attaching/Adjusting Throttle Cable 2A-7 TORQUE SPECIFICATIONS Fastener Location Lbs. Ft. (N.m) Battery Cables Securely Driv DrivDriv e ee Uni UniUni t tt Shif ShifShif t tt Cabl CablCabl e ee Bras BrasBras s ss Barre BarreBarre l ll Spread Cotter Pin Cabl CablCabl e ee En EnEn d dd Guid GuidGuid e ee (Note 1) Front Engine Mount Securely Hose Clamps Securely Rear Engine Mounts 35-40 (47-54) Remot RemotRemot e ee Contro ControContro l ll Shif ShifShif t tt Cabl CablCabl e ee Bras BrasBras s ss Barre BarreBarre l ll Securely Cabl CablCabl e ee En EnEn d dd Guid GuidGuid e ee (Note 1) Remot RemotRemot e ee Contro ControContro l ll Throttl ThrottlThrottl e ee Cabl CablCabl e ee Bras BrasBras s ss Barre BarreBarre l ll Securely Cabl CablCabl e ee En EnEn d dd Guid GuidGuid e ee (Note 1) NOTE 1: Tight, then back nut off 1/2 turn. TOOLS/LUBRICANTS TOOLS/LUBRICANTS 91-57797A3 Engine Alignment Tool 92-86154A1 Quicksilver 2-4-C Multi-Lube REMOVAL position sender wires from terminal block (located on engine harness bracket). NOTICE Stern drive unit must be removed prior to en-4. Remove red and black Power Trim pump motor wires from gine removal. Refer to "Stern Drive Service engine (some models). Manual." 5. Disconnect water inlet hose and exhaust elbow bellows. 6. MCM 120/ 140/165: Remove drive unit shift cable from J rlarip (located on flywheel housing). MCM 120R/140R: Remove both shift cables from shift 1. Disconnect battery cables from batters and remove in- plate assembly (located on exhaust manifold). strument harness connector plug from engine harness 7. Disconnect anv grounding wire or accessories that are receptacle. connected to the engine. 2. Disconnect fuel line and throttle cable. 8. Support engine with suitable sling thru lifting eyes on 3. MCM 120/140/165: Disconnect shift cutout switch engine and remove front and rear engine mounting bolts. wires from terminal block (located on shift plate). 9. (larefullv remove engine. MCM 120/120R/140/140R/165: Disconnect trim 90-95693 485 REMOVAL. INSTALLATION and ALIGNMENT -2A-1 INSTALLATION 1. Lift engine with an overhead hoist, using suitable sling and lifting eyes on engine. 2. Lubricate engine coupling splines with 2-4-C Multi-Lube. 3. Place large fiber washer on top on inner transom plate engine mounting brackets and double wound lockwasher inside fiber washer. (Figure 1) 4. Place engine over transom plate mounting brackets. Place hose clamps over rubber exhaust elbow bellows and position bellows over exhaust elbow outlet. 5. Place steel washers and spacers on mounting bolts and insert bolts down thru rear engine mounts, washers and mounting brackets. Thread elastic stop nuts on bolts. Torque to specification. (Figure 2) a - Double Wound Lockwasher b - Fiber Washer c - Mounting Brackets d - Elastic Stop Nuts (Engine Mounting Bolts) Figure 1. Transom Plate a - Rear Engine Mounting Bolt b - Large Steel Washer c - Metal Spacer d - Rear Engine Mount e - Double Wound Lockwasher f - Fiber Washer g - Mounting Bracket h - Elastic Stop Nut (Hidden) Figure 2. Securing Rear Engine Mounts 16743 2A-2 - REMOVAL, INSTALLATION and ALIGNMENT 90-95693 485 fsffMSgaM 6. Tighten exhaust bellow clamps securely. (Figure 3) i • Secure front engine mount to boat. (Figure 4.1 8. Check engine alignment. Refer to "Alignment". After correct alignment is attained, tighten lower nuts securely (Figure 4) a - Clamps Figure 3. Exhaust Bellows 15927 15930 a - Mounting Bolt Holes b - Lower Nuts Figure 4. Securing Front Engine Mount 90-95693 485 REMOVAL. INSTALLATION and ALIGNMENT - 2A-3 9. Place hose clamp over water inlet hose and place hose over inlet tube. (Figure 5; Tighten clamp securely. 10. Connect instrument harness to engine harness. Secure with clamp and tighten clamp. 11. MCM 120/140/165: Connect shift cutout switch wires as shown in Figure 6. MCM 120/ 120R/ 140/ 140R/ 165: Connect trim position sender wires as shown in Figure 1. a - Water Tube b - Hose Clamp c - Water Hose Figure 5. Water Hose Connection a - Black b - Brown or Gray c - Terminal Block d - Shift Cut-Out Switch Figure 6. MCM 120/140/165 08324 90-95693 485 2A-4 - REMOVAL, INSTALLATION and ALIGNMENT a - Terminal Block b - Brown or Purple Sleeve-, Tq |nsulated Termina| c - Brown/White Wire 1 d - Without Sleeve - To Terminal Block Mounting Screw Figure 7. MCM 120/120R/140/140R/165 12. Connect fuel line. Check for fuel leaks. 13. MCM 120/140/165: Place drive unit shift cable in "J" clamp (located on flywheel housing) and bend clamp closed. MCM 120R/ 140R: Connect drive unit and remote control shift cables as shown in Figure 8. IMPORTANT: Adjust shift cables as outlined in "Stern Drive Service Manual". 14. Connect throttle cable. Refer to "Attaching/Adjusting Throttle Cable". 15. Connect red and black trim pump wires (some models). 16. Connect any ground wires or accessories that mav have been disconnected. 17. Connect batterv cables to batterv. a - Remote Control Shift Cable Attaching Points b - Drive Unit Shift Cable Attaching Points c - Exhaust Manifold Figure 8. MCM 120R/140R ALIGNMENT To ensure more engine coupler engagement during the alignment of MCM 120R and 140R model engines, modify the alignment tool as shown in Figure 1. This modification will improve engine coupler engagement on the other n;odel engines also. IMPORTANT: DO NOT remove more than .560" from gimbal bearing area of alignment tool. This .560" dimension ensures that the gimbal bearing will straddle the existing "under cut" in alignment tool. Figure 1. Alignment Tool Modification 90-95693 485 REMOVAL. INSTALLATION and ALIGNMENT - 2A-5 Figure 2. Alignment Tool Inserted 1. Using Alignment Tool (91-57797A3), insert end of shaft (which does not have threaded hole) thru gimbal bearing. Move gimbal bearing, as required, to insert shaft into engine coupling. (Figure 2) 2. If shaft enters coupling freely with no pressure, alignment is correct. If not, proceed as follows: a. Loosen front mount adjusting nuts and thread either way to raise or lower front of engine until alignment is correct. (Figure 3) b. After correct alignment shaft fit is attained, tighten lower nuts securely. Recheck alignment shaft fit. 2A-6 - REMOVAL, INSTALLATION and ALIGNMENT 90-95693 485 ATTACHING/ADJUSTING THROTTLE CABLE 1. Place remote control in neutral gear, idle position. 2. Fasten cable end guide as shown in Figure 1 or 2. 3. Grasp throttle cable brass barrel and push cable lightly toward throttle lever. Adjust barrel to align with anchor stud or threaded hole in manifold. Fasten barrel as shown in Figure 1 or 2. 4. Check that throttle valves are fully open when remote control is in full throttle position. With throttle valves fully open, check wide open throttle stop screw. Turn screw until it just touches stop, then turn Vt turn more. Tighten locking nut securely to prevent stop screw from turning. 5. Return remote control to neutral gear, idle position. Check that idle stop screw is against stop. a - Cable End Guide d - Stud b - Washer and Nut e - Washer and Nut (DO NOT Over-Tighten) (Tighten Securely) c - Brass Ba'rel f - W.O.T. Stop Screw Figure 1. MCM 120/140/165 a - Cable End Guide b - Anchor Screw (Tighten Securely) c - Brass Barrel (Cable Must Be Positioned As Shown) d- W.O.T. Throttle Stop e - W.O.T. Throttle Stop Screw f - Washer and Nut (DO NOT Over-Tighten) Figure 2. MCM 120R/140R 07416 90-95693 485 REMOVAL. INSTALLATION and ALIGNMENT - 2A-7 SECTION 2 - REMOVAL, INSTALLATION and ALIGNMENT PART B - MCM 120R-140R DRIVE SHAFT EXTENSION MODELS INDEX Page Torque Specifications 2B-1 Tools/Lubricants 2B-1 Removal 2B-2 Installation 2B-3 Alignment 2B-5 Bearing Support Installation 2B-5 Alignment 2B-6 Attaching/Adjusting Throttle Cable 2B-10 TORQUE SPECIFICATIONS Fastener Location Lbs. Ft. (N.m) Battery Cables Securely Bearing Support to Inner Transom Plate 50(68) Drive Shaft 50 (68) Drive Shaft Snield 30 (41) Extension Housing to Flywheel Housing 30 (41) Flywheel Housing 30 (41) Front and Rear Engine Mounts Securely Hose Clamps Securely Rear Engine Mount Bracket 50 (68) Remot RemotRemot e ee Contro ControContro l ll Throttl ThrottlThrottl e ee Cabl CablCabl e ee Bras BrasBras s ss Barre BarreBarre l ll Securely Cabl CablCabl e ee En EnEn d dd Guid GuidGuid e ee (Note 1) NOTE 1: Tight, then back nut off 1/2 turn. TOOLS/LUBRICANTS TOOLS/LUBRICANTS 91-57797A3 Engine Alignment Tool 92-86154A1 Quicksilver 2-4-C Multi-Lube 9-GT-3984 Sears Craftsman Universal Protractor 90-95693 485 REMOVAL AND INSTALLATION -2B-1 REMOVAL NOTICE Stem drive unit must be removed prior to engine removal. Refer to "Stern Drive Service Manual." 1. Disconnect batterv cables from batterv and remove instrument harness plug from engine harness receptacle. 2. Disconnect fuel line and throttle cable. 3. Slide sleeves back on black and white/green wires and disconnect engine harness wires from shift cut-out switch harness. 4. Disconnect brown/white wire from terminal block (on engine harness plug bracket). 5. Disconnect water inlet hose (from thermostat housing). 6. Disconnect exhaust pipe from exhaust hose. 7. Remove top shield and then bottom shield. (Figure 1) a - Mounting Bolts Figure 3. Front Mount a - Output Flange b - Drive Shaft c - Screw/Nut (4) Figure 2. Disconnecting Drive Shaft a - Top Shield c - 4 Screws/Nuts (2 Hidden) b - Bottom Shield d - 3 Screws (Hidden) Figure 1. Top/Bottom Shield Removal 8. Disconnect drive shaft from output flange. (Figure 2) 9. Disconnect any grounding wire or accessories that are connected to the engine. IMPORTANT: To avoid the need for a complete realignment (after engine repair), DO NOT move front or rear mounts. Remove mounting bolts as shown in Figures 3 and 4. 10. Support engine with suitable sling thru lifting eyes on engine and remove front and rear engine mounting bolts as shown in Figures 3 and 4. 11. Carefully remove engine. 2B-2 - REMOVAL AND INSTALLATION 90-95693 485 a Mounting 3olts Figure 4. Rear Mounts a Mounting 3olts Figure 4. Rear Mounts INSTALLATION NOTICE If engine mounts or drive shaft have been changed, refer to "Alignment" before starting installation. 1. Lift engine with an overhead hoist, using suitable sling and lifting eves on engine. 2. Set engine on stringers. 3. Connect drive shaft to output flange. Torque screws and nuts to specifications. 4. Relieve hoist tension from engine: then slideengine fore or aft as needed to obtain a Vi" (6mm) between flange shoulder and extension shaft housing bearing, (f igure 1) IMPORTANT: Failure to properly position output a - Flange Shoulder shaft flange (as described following) may result in b - Bearing c - 1/4" (6rrm) bearing damage. Figure 1. Distance Between Output Shaft Shoulder and Bearing a - Distance Between Bearing Support Attaching Bolts and Grease Fitting b - Distance Between Bearing Support Attaching Bolts and Engine Mount Bolts Figure 2. Engine Alignment 90-95693 485 REMOVAL AND INSTALLATION - 2B-3 5. Measure distance between the center of the bearing support attaching bolts and rear engine mount adjusting bolt, as shown in Figure 2. These distances ML ST BE equal. If not, slide front of engine to one side or the other until distances are equal. 6. After engine has been aligned correctly, fasten front and rear engine mounts to stringers. 7. Install top and bottom shield. Torque screws to specifications. (Figures 3 and 4) 8. Connect exhaust pipe to exhaust hose. (Figure 5) 9. Connect water inlet hose to thermostat housing. 10. Reconnect shift cut-out switch harness to engine harness. (Figure 6) 16501 16503 a - Shaft Housing b - Bottom Shield c - Screws (Threads of screws are coated with Loctite) Figure 3. Bottom Shield Figure 6. Switch HARNESS a - Exhaust Pipe b - Exhaust Hose c - Clamps (Tighten Securely) d - Exhaust Tube Figure 5. Exhaust Connection Engine Harness 2B-4 - REMOVAL AND INSTALLATION 90-95693 485 11. Connect instrument harness to engine harness. Tighten clamp. 12. Connect trim position sender brown/ white wire as shown in Figure 7. 13. Connect fuel line. Check for leaks. 14. Connect throttle cable. Refer to "Attaching/Adjusting Throttle Cable". 15. Connect any grounding wires or accessories tha: may have been disconnected. 16. Connect battery cables to battery. IMPORTANT: If stern drive unit was removed, refer to step 14 in "Alignment". a - Terminal Block b - Brown/White Wires Figure 7. Sender Connection ALIGNMENT BEARING SUPPORT INSTALLATION The following procedure MUST BE used when installing bearing support on MCM 120R/140R Models: 15942 a - Bolt (2) b - Flat Washer (2) c - Spherical Washer (4) (Install with Rounded Side Toward Bearing Support) d - Bearing Support e - Nut (2) Figure 1. Bearing Support Attaching Parts 1. Install bearing support, as shown in Figure 1. DO NOT tighten bolts. 2. Insert solid end of Alignment Tool (91-57797A3) thru bearing in gimbal housing and into input shaft splines. (Figure 2) 3. Tighten bearing support bolts until snug (5-10 lbs. ft. (7-13 N.m)J. Strike the head of both bolts with a ball peen hammer, then torque bolts to specifications. a - Alignment Shaft Figure 2. Alignment Tool Installed IMPORTANT: Bearing support attaching bolts MUST BE struck with a hammer to properly seat spherical washers. If procedure is not followed, difficulty in installing stern drive unil may result and subsequent damage to bearings may occur from misalignment. 90-95693 485 REMOVAL AND INSTALLATION - 2B-5 ALIGNMENT IMPORTANT: A Sears Craftsman Universal Protractor (stock number 9-GT-3984) or equivalent is required for measuring the angles in the following steps. Protractor readings will be taken off of vertical and horizontal surfaces; therefore, both the 0C and the 90° marks will be used. It should be kept in mind that these are reference marks only and the actual numbers should be ignored. (Figure 3) It is only necessary to note the number of degrees and to which side (left or right) of the reference marks the indicator needle rests. PROTRACTOR MUST BE VIEWED FROM THE SAME SIDE OF POWER PACKAGE THROUGHOUT ALIGNMENT. When attaching drive shaft in next step. BE SURE that the pilots on drive shaft flanges are engaged in input shaftand output shaft flanges. Flanges MUST BE flush to each other prior to tightening screws, or screws may come loose during operation. 4. Attach dr:ve shaft to input shaft flange and output shaft flange, as shown in Figures 5 and 6. 5. Position base of protractor on drive shaft (Figure 7); then, adjust engine mounts so that indicator needle is 1° to 3° on either side of reading taken in Step 2. Record this reading in the following chart for later use. IMPORTANT: A minimum of 1A" (6mm) up-anddown engine mount adjustment must exist after engine has been properly aligned. This is necessary to allow for realignment of the engine in the future. If mount travel is insufficient, boat stringer height MUST BE adjusted. 1. Insert solid end of alignment tool thru bearing in gimbal housing and into bearing support input shaft splines. (Figure 2) 2. Position base of protractor against input shaft flange, as shown in Figure 4. NOTE and RECORD the number of degrees and to which side of the reference mark the indicator needle has moved in the chart following. IMPORTANT: Be sure that boat does not move once reading has been taken from input shaft flange, as this reading establishes reference pointforaligning drive shaft and engine following. 3. Lift engine into boat, using an overhead hoist and a chain (attached to lifting eyes oil engine). a - Input Shaft Flange b - Protractor c - Indicator Needle Figure 4. Measuring Angle of Input Shaft Flange 2B-6 - REMOVAL AND INSTALLATION 90-95693 485 a - Drive Shaft b - Protractor c - Output Shaft Flange Figure 7. Measuring Drive Shaft Angle 16497 IMPORTANT: Failure to properly position engine (as described following) may result in bearing damage. 6. Relieve hoist tension from engine, then slide engine fore or aft as needed to obtain a XA" (6mm) between flange a - Input Shaft Flange b - Drive Shaft c - Screw (4 Used) (Torque to Specifications) d - Nut (4 Used) Figure 5. Drive Shaft Attached to Input Shaft Flange 16284 shoulder and extension shaft housing bearing, as shown in Figure 8. Engine MUST BE aligned correctly to achieve proper engine operation and to prevent damage to drive shaft. If drive shaft is run at an incorrect angle, damage to universal joint bearings may result. a - Output Shaft Flange b - Drive Shaft c - Screw (4 Used) (Torque to Specifications) d - Nut (4 Used) Figure 6. Drive Shaft Attached to Output Shaft Flange a - Flange Shoulder b - Bearing c - 1/4" (6mm) Figure 8. Distance Between Output Shaft Shoulder and Bearing 90-95693 485 REMOVAL AND INSTALLATION - 2B-7 a - Distance Between Bearing Support Attaching Bolts and Grease Fitting b - Distance Between Bearing Support Attaching Bolts and Engine Mo'jrt Bolts Figure 9. Engine Alignment 7. Position engine for correct engine and drive shaft lateral alignment as follows: a. The distance bet ween the center of the beari ng support attaching bolts (on inner transom plate) and grease fitting on shafl extension housing (Figure 9) Ml ST BF equal. If not. slide af t end of engine to one side or the other until distances are equal. b. Measure distance between the center of the bearing support attaching bolls and rear engine mounl adjusting boll, as shown in Figure 9. These distances also. M I. ST BE equal. If not. slide front of engine to one side or the other until distances are equal. 8. \fter engine has been aligned correctlv. fasten frcnl and rear engine mounts to stringers. 9. Position protractor on starter housing cover plate, as shown in Figure 10. Now. raise or lower Iron! engine mounl adjusting nutsas required so that prolractor needle reads exactlv the same number of degrees as that recorded in Step 2. 16499 a - Top Shield b - Bottom Shield c - Screw (4 Used) d - Nut (4 Used) (Torque to Specifications) Figure 11. Top Shield Attached to Bottom Shield at Transom End 10. Position protractor on drive shall (as shown in Figure 7) ami recheck angle. \ngle should he the same as that recorded in Step 5. If not, raise or lower all engine mount adjusting mils an equal amount until correct angle is reached. 1 I. Tighten \l.I. engine mounl locking mils securely. 12. Remove alignment shall Irom gimhal housing. 13. Install dri\c shafl shields. (Figures 1 I and 12) a - Flywheel Housing b - Starter Housing Cover Plate c - Protractor Figure 10. Protractor Positioned Correctly on Starter Housing Cover Plate 2B-8 - REMOVAL AND INSTALLATION 90-95693 485 14. Install stern drive unit. Stern drive unit installation procedure is the same as that for the standard models, with the following exceptions: • \o alignment is necessary, other than to align gimbal bearing with bearing support input shaft. Step 2 and 3. • Stern drive universal joints MUST BE aligned with drive shaft universal joints, as shown in Figures 13 and 14. Place a reference mark (white paint) on shafts to correspond with universal joint centerlines. After installing stern drive, check to ensure that these marks are in alignment. a - Imaginary Centerline Running Thru This Universal Joint Bearing Must Be Vertical b - Place a Reference Mark Here To Correspond with "a" Figure 13. Aligning Drive Shaft Universal Joint 16503 a - Top Shield b - Bottom Shield c - Screw (4 Used) d - Nut (4 Used) (Torque to Specifications) Figure 12. Top Shield Attached to Bottom Shield at Engine End a - Imaginary Centerline Running Thru This Universal Joint Bearing Must Be Vertical (Once Drive Unit Is Installed) b - Place a Reference Mark Here To Correspond with "a" Figure 14. Aligning Stern Drive Unit Universal Joints 90-95693 485 REMOVAL AND INSTALLATION - 2B-9 ATTACHING/ADJUSTING THROTTLE CABLE 1. Place remote control in neutral gear, idle position. 2. Fasten cable end guide as shown in Figure 1. 3. Grasp throttle cable brass barrel and push cable lightly toward throttle lever. Adjust barrel to align with threaded hole in manifold. Fasten barrel as shown in Figure 1. 4. Check that throttle valves are fully open when remote control is in full throttle position. With throttle valves fully open, check wide open throttle stop screw. Turn screw until it just touches stop, then turn Vi turn more. Tighten set nut securely to prevent stop screw from turning. (Figure 1) 5. Return remote control to neutral gear, idle position. Check that idle stop screw is against stop. a - Cable End Guide b - Anchor Screw (Tighten Securely) c - Brass Barrel (Cable Must Be Positioned As Shown) d - W.O.T. Throttle Stop e - W.O.T. Throttle Stop Screw f - Washer and Nut (DO NOT Over-Tighten) g - Throttle Lever Figure 1. MCM 120R/140R 2B-10 - REMOVAL AND INSTALLATION 90-95693 485 SECTION 2 - REMOVAL, INSTALLATION and ALIGNMENT PART C - MCM 470-485-488 INDEX Page Torque Specifications 2C-1 Tools/Lubricants 2C-1 Removal 2C-2 Installation 2C-3 Alignment 2C-6 Attaching/Adjusting Throttle Cable 2C-7 TORQUE SPECIFICATIONS Fastener Location Lbs. Ft. (N.m) Lbs. In. (N.m) Battery Cables Securely Driv DrivDriv e ee Uni UniUni t tt Shif ShifShif t tt Cabl CablCabl e ee Bras BrasBras s ss Barre BarreBarre l ll Spread Cotter Pin Cabl CablCabl e ee En EnEn d dd Guid GuidGuid e ee (Note 1) Front Engine Mount Securely Hose Clamps Securely Powe PowePowe r rr Steerin SteerinSteerin g gg Flui FluiFlui d dd Hos HosHos e ee Fitting FittingFitting s ss Larg LargLarg e ee 20-25 (27-34) Smal SmalSmal l ll 96-108 (11-12) Rear Engine Mounts 35-40 (47-54) Remot RemotRemot e ee Contro ControContro l ll Shif ShifShif t tt Cabl CablCabl e ee Bras BrasBras s ss Barre BarreBarre l ll Securely Cabl CablCabl e ee En EnEn d dd Guid GuidGuid e ee (Note 1) Remot RemotRemot e ee Contro ControContro l ll Throttl ThrottlThrottl e ee Cabl CablCabl e ee Bras BrasBras s ss Barre BarreBarre l ll Securely Cabl CablCabl e ee En EnEn d dd Guid GuidGuid e ee (Note 1) Upper Exhaust Pipe 180 (20) NOTE 1: Tight, then back nut off 1/2 turn. TOOLS/LUBRICANTS TOOLS/LUBRICANTS 91-57797 A3 Engine Alignment Tool 92-86154A1 Quicksilver 2-4-C Multi-Lube REMOVAL. INSTALLATION and ALIGNMENT -2C-1 90-95693 485 REMOVAL NOTICE Stern drive unit must be removed prior to engine removal. Refer to "Stern Drive Service Manual." 1. Disconnect battery cables from battery and remove instrument harness connector plug from engine harness receptacle. 2. Disconnect fuel line and throttle cable. 3. MCM 470/485: Disconnect shift cutout switch wires from terminal block (located on shift plate). MCM 470/470R/485/488R: Disconnect trim position sender wires from terminal block. 4. Remove red and black Power Trim pump motor wires from engine (some models). 5. Disconnect water inlet hose and exhaust elbow bellows. MCM 470R/485/488R: To remove engine from boat, it may be necessary to remove upper exhaust pipe as shown in Figure 1. 6. MCM 470/485: Remove drive unit shift cable from "J" clamp (located on flvwheel housing). MCM 470K/488R : Remove both shift cables from shift plate assembly (located on exhaust manifold). 7. Disconnect any grounding wire or accessories that are connected to the engine. 8. Power Steering; Models: Disconnect fluid hoses from power steering control valve. 9. Support engine with suitable sling thru lifting eves on engine and remove front and rear engine mounting bo!i>. 10. Carefullv remove engine. 15966 a - Clamps b - Upper Exhaust Pipe c - Socket Head Screws Figure 1. MCM 470R/485/488R 2A-2 - REMOVAL, INSTALLATION and ALIGNMENT 90-95693 485 INSTALLATION 1. Lift engine with an overhead hoist, using suitable sling and lifting eves on engine. 2. Lubricate engine coupling splines with 2-4-C Multi-Lube. 3. Place large fiber washer on top of transom plate engine mounting brackets and double wound lockwasher inside fiber washer. (Figure 1) 16743 a - Double Wound Lockwasher b - Fiber Washer c - Mounting Bracket d - Elastic S:op Nuts (Engine Mounting Bolts) Figure 1. Transom Plate 4. Place engine over transom plate mounting brackets. Place hose clamps over rubber exhaust elbow bellows and position bellows over exhaust manifold outlet. 5. Place steel washers and spacers on mounting oolts and insert bolts down thru rear engine mounts. (Figure 2) washers and mounting brackets. Thread elastic stop nuts on bolts. Torque to specification. 6. MCM 470R/485/488R: If removed, connect upper exhaust pipe to lower exhaust pipe as shown in Figure 3. All Models: Tighten exhaust bellow clamps securely. (Figure 3) 7. Secure front engine mount to boat. (Figure 4) a - Rear Engine Mounting Bolts e - Double Wound Lockwasher b - Large Steel Washer f - Fiber Washer c - Metal Spacer g - Mounting Bracke:s d - Rear Engine Mount h - Elastic Stop Nut (Hidden) Figure 2. Securing Rear Engine Mounts 90-95693 485 REMOVAL. INSTALLATION and ALIGNMENT - 2A-3 a - Mounting Bolts b - Lower Nuts Figure 4. Securing Front Engine Mount 8. Check eng:ne alignment. Refer to Xlignment . \fier correct alignment is attained, tighten lower nuts securely. (Figure 4) 9. Place hose clamp over water inlet hose and place hose over inlet tube. (Figure 5) Tighten clamp securelv. a - Clamps b - Upper Exhaust Pipe c - Socket Head Screws (Torque to Specifications) d - MCM 485 - Gasket. MCM 470R/488R - "O" Ring Figure 3. Exhaust System Connection a - Water Tube b - Hose Clamp c - Water Hose Figure 5. Water Hose Connection 2A-4 - REMOVAL, INSTALLATION and ALIGNMENT 90-95693 485 10. Connect instrument harness to engine harness. Secure with clamp and tighten securely. 11. MCM 470/485: Connect shift cutout switch wires as shown in Figure 6. MCM 470/470R/485/488R: Connect trim position sender wires as shown in Figure 7. a - Remote Control Shift Cable Attaching Points b - Drive Unit Shift Cable Attaching 3oints c - Exhaust Manifold Figure 8. MCM 470R/488R 12. Connect fuel line. Check for fuel leaks. 13. MCM 470/485 : Place drive unit shift cable in "J" clamp (located on fh wheel housing) and bend clamp closed. MCM 470R/488R : Connect drive unit and remote control shift cables as shown in Figure 8. IMPORTANT: Adjust shift cables as outlined in "Stern Drive Service Manual". 14. Connect throttle cable. Refer to "Attaching/Adjusting Throttle Cable". 15. Connect red and black trim pump wires (some models). 16. Connect an\ ground wires or accessories that mav have been disconnected. 17. Power Steering Models: Reconnect fluid hoses as shown in Figure 9. IMPORTANT: Bleed power steering system as outlined in "Stern Drive Service Manual". 18. Connect batierv cables to batterv. 16750 a - Terminal Block b - Brown or Purple Sleeve 1 To Insulated c - Brown/White Wire ' Termina d - Without Sleeve - To Terminal Block Mounting Screw Figure 7. MCM 470/470R/485/488R REMOVAL. INSTALLATION and ALIGNMENT - 2A-5 90-95693 485 ALIGNMENT To ensure more engine coupler engagement during the alignment of MCM 470R and 488R model engines, modify the alignment tool as shown in Figure 1. This modification will improve engine coupler engagement on the other model engines also. IMPORTANT: DO NOT remove more than .560" from gimbal bearing area of alignment tool. This .560" dimension ensures that the gimbal bearing will straddle the existing "under cut" in alignment tool. Figure 1. Alignment Tool Modification 1. Using Alignment Tool (91-57797A3), insert end of shaft (which does not have threaded hole) thru gimbal bearing. Move gimbal bearing, as required, to insert shaft into engine coupling. (Figure 2) Figure 2. Alignment Tool Inserted 2A-6 - REMOVAL, INSTALLATION and ALIGNMENT 90-95693 485 2. If shaft enters coupling freely with no pressure, alignment is correct. If not, proceed as follows: a. Loosen front mount adjusting nuts and thread either way to raise or lower front of engine until alignment is correct. (Figure 3) b. After correct alignment shaft fit is attained, tighten lower nuts securely. Recheck alignment shaft fit. a - Upper Nut b - Raise 1 .. . . _ Front of Engine c - Lower 1 d - Lower Nuts Figure 3. Adjusting Front Mount ATTACHING/ADJUSTING THROTTLE CABLE 1. Place remote control in neutral gear, idle position. 2. Fasten cable end guide as shown in Figure 1 or 2. 3. Grasp throttle cable brass barrel and push cable lightly toward throttle lever. Adjust barrel to align wi;h anchor stud. Fasten barrel as shown in Figure 1 or 2. a - Cable End Guide b - Washer and Nut (DO NOT Over-Tighten) c - Brass Barrel d - Stud e - Washer and Nut (DO NOT Over-Tighten) f - W.O.T. Stop Screw g - Idle Stop Screw Figure 1. MCM 470/470R/485 13240 90-95693 485 REMOVAL. INSTALLATION and ALIGNMENT - 2A-7 Check that throttle valves are fully open when remote control is in full throttle position. (Figure 1 or 3) MCM 470/470R/485: With throttle valves fully open, check wide open throttle stop screw. Turn screw until it just touches stop, then turn '/* turn more. Tighten set nut securely to prevent stop screw from turning. Return remote control to neutral gear, idle position. Check that idle stop screw is against stop. (Figure 1 or 3) a - Anchor Stud b - Washer and Nut (DO NOT Over-Tighten) c - Brass Barrel d - Cable End Guide e - Screw f - Washer and Nut (DO NOT Over-Tighten) g - Bushing Figure 2. MCM 488R a - Tang b - Carburetor Body c - Idle RPM Adjustment Screw Figure 3. MCM 488R IDLE WOT 17302 90-95693 485 2A-8 - REMOVAL, INSTALLATION and ALIGNMENT SECTION 2 - REMOVAL, INSTALLATION and ALIGNMENT PART D - MCM 898-228-260 INDEX Page Torque Specifications 2D-1 Tools/Lubricants 2D-1 Removal 2D-2 Installation 2D-2 Alignment 2D-5 Attaching/Adjusting Throttle Cable 2D-7 MODEL IDENTIFICATION MCM 898/228/260 MCM 898R/228R/260R TORQUE SPECIFICATIONS Fastener Location Lbs. Ft. (N.m) Lbs. In. (N.m) Battery Cables Securely Driv DrivDriv e ee Uni UniUni t tt Shif ShifShif t tt Cabl CablCabl e ee Bras BrasBras s ss Barre BarreBarre l ll Spread Cotter Pin Cabl CablCabl e ee En EnEn d dd Guid GuidGuid e ee (Note 1) Front Engine Mount Securely Hose Clamps Securely Powe PowePowe r rr Steerin SteerinSteerin g gg Flui FluiFlui d dd Hos HosHos e ee Fitting FittingFitting s ss Larg LargLarg e ee 20-25 (27-34) Smal SmalSmal l ll 96-108 (11-12) Rear Engine Mounts 35-40 (47-54) Remot RemotRemot e ee Contro ControContro l ll Shif ShifShif t tt Cabl CablCabl e ee Bras BrasBras s ss Barre BarreBarre l ll Securely Cabl CablCabl e ee En EnEn d dd Guid GuidGuid e ee (Note 1) Remot RemotRemot e ee Contro ControContro l ll Throttl ThrottlThrottl e ee Cabl CablCabl e ee Bras BrasBras s ss Barre BarreBarre l ll Securely Cabl CablCabl e ee En EnEn d dd Guid GuidGuid e ee (Note 1) NOTE 1: Tighten, then back nut off 1/2 turn. TOOLS/LUBRICANTS TOOLS/LUBRICANTS 91-57797A3 Engine Alignment Tool 92-86154A1 Quicksilver 2-4-C Multi-Lube 90-95693 485 REMOVAL, INSTALLATION and ALIGNMENT -2E-1 REMOVAL wires are disconnected, remove wires from clamps that INSTALLATION NOTICE Stern drive unit must be removed prior to engine removal. Refer to "Stern Drive Service Manual". 1. Disconnect batterv cables from battery and remove instrument harness connector plug from engine harness receptacle. 2. Disconnect fuel line and throttle cable. 3. MCM 898/228/260: Disconnect trim position sender wires (coming from gimbal housing) from terminal block on engine harness mounting plate. MCM 898R/228R/260R: Disconnect trim position sender wires (coming from gimbal housing) from terminal block on circuit breaker/solenoid mounting bracket, \fter 1. Lift engine with an overhead hoist, using suitable slingand lifting eyes on engine. 2. Lubricate engine coupling splines with 2-4-C Multi-Lube. 3. Place large fiber washer on lop on transom plate engine mounting brackets and double wound lockwasher inside fiber washer. (Figure 1) "i. 16651 a - Double Woi.nd Lockwasher b - Fiber Washer c - Mounting Bracket d - Elastic Stop Nuts (Engine Mounting Bolts) Figure 1. Transom Plate 4. Place engine over transom plate mounting brackets. Place hose clamps over rubber exhaust elbow bellows. 5. Place steel washers and spacers on mounting bolts and insert bolts down thru rear engine mounts. (Figure 2) hold the power steering hoses. 4. MCM 898/228/260 only: Remove plastic tubing and grav hvdraulic hose from Power Trim reverse lock valve. 5. Remove red "and black Power Trim pumpxnotor wires from engine (some models). 6. Disconnect water inlet hose and exhaust elbow bellows. 7. Remove both shift cables from shift plate. 8. Disconnect anv grounding wire or accessories that are connected to the engine. 9. Power Steering Models: Disconnect fluid hoses from power steering control valve. 10. Support engine with suitable slirig thru lifting eyes on engine and remove front and rear engine mounting bolts. 11. Garefullv remove engine. washers and mounting brackets. Thread elastic stop nuts on bolts. Torque to specification. a - Rear Engine Mounting Bolts b - Large Steel Washer c - Metal Spacer d - Rear Engine Mount e - Fiber Washer With Double Wound Lockwasher in the Center f- Mounting Brackets g - Elastic Stop Nut (Hidden) Figure 2. Securing Rear Engine Mounts 6. Tighten al. exhaust bellow clamps securely. . Secure front engine mounts to boat. (Figure 3) 2E-2 - REMOVAL. INSTALLATION and ALIGNMENT 90-95693 485 11. Connect trim position sender wires as follows: MCM 898/228/260: Figure 5 MCM 898R/228R/260R: Figures 6 and 7. 11908 a - Mounting Bolts b - Locknut and Lockwasher Figure 3. Securing Front Engine Mounts 8. Check engine alignment. Refer to "Alignment". After correct alignment is attained, tighten locknuts securely. (Figure 3) 9. Place hose clamp over water inlet hose and place hose over inlet tube. (Figure 4) Tighten clamp securely. 13035 15913 a - Water Inlet Tube b - Hose Clamp c - Water Inlet Hose Figure 4. Water Hose Connection 10. Connect instrument harness to engine harness. Secure with clamp and tighten securelv. a - Power Steering Hydraulic Hose b - Hose Clips c - Trim Position Sender Wires (Route Thru Hose Clips) d - Sta-Strap Leads at This Location Figure 6. MCM 898R/228R/260R 90-95693 485 REMOVAL. INSTALLATION and ALIGNMENT - 2A-3 15912 15912 a - Remote Control Shift Cable Ancho* Points b - Drive Unit Shift Cable Anchor Points Figure 9. MCM 898R/228R/260R 14. MCM 898/228/260 only: Connect Power Trim hydraulic hoses as shown in Figure 10. a - White Plastic Tubing (from Power Trim Pump) b - Elbow Fitting c - Straight Fitting d - G'ay Hydraulic Hose (from Gimbal Housing) e - Reverse Lock Valve Figure 10. Power Trim Hose Connected to Reverse Lock Valve a - Remote Control Shift Cable Anchor Points b - Drive Unit Shift Cable Anchor Points Figure 8. MCM 898/228/260 2A-4 - REMOVAL, INSTALLATION and ALIGNMENT 90-95693 485 15. Connect throttle cable. Refer to "Attaching/Adjusting Throttle Cable". 16. Connect red and black trim pump wires (some models). 17. Connect any ground wires or accessories that may have been disconnected. 18. Power Steering Models: Reconnect fluid hoses as shown in Figure 11. IMPORTANT: Bleed power steering system as outlined in "Stern Drive Service Manual". 19. Connect batterv cables to batterv. a - Control Valve b - Small Fitting _ Torque t0 c - Large Fitting • Specifications Figure 11. Power Steering Connections 15792 ALIGNMENT To ensure more engine coupler engagement during the alignment of MCM 898R/228R/260R model engines, modify the alignment tool as shewn in Figure 1. This modification will improve engine coupler engagement on the other model engines also. IMPORTANT: DO NOT remove more than .560" from gimbal bearing area of alignment tool. This .560" dimension ensures that the gimbal bearing will straddle the existing "under cut" in alignment tool. Figure 1. Alignment Tool Modification 90-95693 485 REMOVAL. INSTALLATION and ALIGNMENT - 2A-5 1. Using Alignment Tool (91-57797A3), insert end of shaft (which does not have threaded hole) thru gimbal bearing. Move gimbal bearing, as required, to insert shaft into engine coupling. (Figure 2) Figure 2. Alignment Tool Inserted 2. If shaft enters coupling freely with no pressure, alignment is correct. If not, proceed as follows (Figure 3): a. Loosen locknut on both front engine mounts. b. Thread adjusting nut either way to raise or lower front of engine. IMPORTANT: Raise or lower each side of the engine the same amount. Care must be taken not to "cock" front of engine. c. After correct alignment shaft fit is attained, tighten locknuts securely. Recheck alignment shaft fit. 2A-6 - REMOVAL, INSTALLATION and ALIGNMENT 90-95693 485 ATTACHING/ADJUSTING THROTTLE CABLE 1. Place remote control in neutral gear, idle position. 2. Fasten cable end guide as shown in Figure 1 or 2. 3. Grasp throttle cable brass barrel and push cable lightly toward throttle lever. Adjust barrel to align with anchor stud. Fasten barrel as shown in Figure 1 or 2. 4. Check that throttle valves are fully open when remote control is at full throttle position. Level tang should be against stop as shown in Figure 3 or 4. 5. Return remote control to neutral gear, idle position. Check that idle stop screw is against stop. (Figure 1 or 4) a - Throttle Lever Tang Against Stop Figure 3. MCM 898/898R 10176 a - Cable End Guide b - Washer. Nut, Screw and Bushing (DO NOT Over-_ighten) c - Brass Barrel d - Stud e - Washer and Nut iDO NOT Over-Tighten) f - Idle Stop Screw a - Cable End Guide b - Bushing c - Washer, Nut and Screw (DO NOT Over-Tighten) d - Spacer e - Brass Barrel f - Washer and Nut (DO NOT Over-Tighten) 15804 g - Anchor Stud Figure 2. MCM 228/228R/260/260R 90-95693 485 REMOVAL. INSTALLATION and ALIGNMENT - 2A-7 SECTION 2 - REMOVAL, INSTALLATION and ALIGNMENT PART E - MCM 898-228-260 DRIVE SHAFT EXTENSION MODELS INDEX Page Torque Specifications 2E-1 Tools/Lubricants 2E-1 Removal 2E-2 Installation 2E-3 Alignment 2E-5 Bearing Support Installation 2E-5 Alignment 2E-6 Attaching/Adjusting Throttle Cable 2E-10 MODEL IDENTIFICATION TORQUE SPECIFICATIONS Fastener Location Lbs. Ft. (N.m) Battery Cables Securely Bearing Support to Inner Transom Plate 35-40 (47-54) Drive Shaft 50 (68) Drive Shaft Shield 30 (41) Extension Housing to Flywheel Housing 30(41) Flywheel Housing 30(41) Front and Rear Engine Mounts Securely Hose Clamps Securely Rear Engine Mount Bracket 50 (68) Remot RemotRemot e ee Contro ControContro l ll Throttl ThrottlThrottl e ee Cabl CablCabl e ee Bras BrasBras s ss Barre BarreBarre l ll Securely Cabl CablCabl e ee En EnEn d dd Guid GuidGuid e ee (Note 1) NOTE 1: Tighten, then back nut off 1/2 turn. TOOLS/LUBRICANTS TOOLS/LUBRICANTS 91-57797A3 Engine Alignment Tool 92-86154A1 Quicksilver 2-4-C Multi-Lube 9-GT-3984 Sears Craftsman Universal Protractor 90-95693 485 REMOVAL, INSTALLATION and ALIGNMENT -2E-1 REMOVAL NOTICE Stern drive unit does not have to be removed prior to engine removal. If stern drive is going to be removed, refer to "Stern Drive Service Manual." 1. Disconnect battery cables from battery and remove instrument harness plug from engine harness receptacle. 2. Disconnect fuel line and throttle cable. 3. Slide sleeves back on black and white/green (or gray) wires and disconnect engine harness wires from shift cut-out switch harness. 4. Disconnect trim position sender brown/white wire from terminal block on engine. MCM 898/228/260: Terminal block located above circuit breaker on engine harness mounting bracket. MCM 898R/228R/260R: Terminal'block located on circuit breaker/solenoid mounting bracket. After wires are disconnected, remove wires from clamps that hold the power steering hoses. 5. Disconnect water inlet hose (from engine seawater pump). 6. Disconnect exhaust pipes from exhaust hoses. 7. Remove top shield and then bottom shield. (Figure 1) 16300 a - Top Shield b - Bottom Shield c - 4 Screws/Nuts (2 Hidden) d - 3 Screws (Hidden) Figure 1. Top/Bottom Shield Removal 8. Disconnect drive shaft from output flange. (Figure 2) a - Output Flange b - Drive Shaft c - Screw/Nut (4) Figure 2. Disconnecting Drive Shaft 9. Disconnect fluid hoses from power steering control valve (located on transom plate). 10. Disconnect any grounding wire or accessories that are connected to the engine. IMPORTANT: To avoid the need for a complete realignment (after engine repair), DO NOT move front or rear mounts. Remove mounting bolts as shown in Figure 3. 11. Support engine with suitable sling thru lifting eyes on engine and remove front and rear engine mounting bolts, as shown in Figure 3. 12. Carefully remove engine. a - Mounting Bolts Figure 3. Front and Rear Mounts 2E-2 - REMOVAL. INSTALLATION and ALIGNMENT 90-95693 485 INSTALLATION 5. Position engine for correct engine and drive shaft lateral NOTICE If engine mounts or drive shaft have been changed, refer to "Alignment" before starling installation. 1. Lift engine with an overhead hoist, using suitable slingand lifting eyes on engine. 2. Set engine on stringers. 3. Connect drive shaft to output flange. Torque screws and nuts to specifications. 4. Relieve hoist tension from engine; then slide engine fore or aft as needed to obtain a 'A" (6mm) between flange shoulder and extension shaft housing bearing. (Figure 1) IMPORTANT: Failure to properly position output shaft flange may result in bearing damage. a - Flange Shoulder b- Bearing c - 1/4" (6mm) Figure 1. Distance Between Output Shaft Shoulder and Bearing alignment as follows (Figure 2): a. The distance between the center of the bearing support attaching bolts on inner transom plate and grease fitting on shaft extension housing MUST BE equal. If not. slide aft end of engine to one side or the other until distances are equal. b. Measure distance between the center of the bearing support attaching bolts and rear engine mount adjusting bo.t. These distances also, MUST BE equal. If not, slide front of engine to one side or the other until distances are equal. 6. After engine has been aligned correctly, fasten front and rear engine mounts to stringers. 7. Install top and bottom shield. Torque screws to specifications. (Figures 3 and 4) a - Shaft Housing b - Bottom Shield c - Screws (Threads of Screws Are Coated with Loctite) Figure 2. Engine Alignment 90-95693 485 REMOVAL, INSTALLATION and ALIGNMENT - 2E-11 16300 16300 a - Top Shield b - Bottom Shield c - Screw (4 Used) d - Nut (4 Used) Figure 4. Top Shield 9. Connect water inlet hose to seawater pump. 10. Reconnect shift cut-out switch harness to engine harness. (Figure 6) 8. Connect exhaust pipes to exhaust hoses. (Figure 5l 11. Connect instrument harness to engine harness. Tighten clamp. 12. Connect trim position sender brown/white wire as shown in Figure 7 or 8. a - Exhaust Pipe b - Exhaust Hose c - Clamps (Tighten Securely) d - Exhaust Tube Figure 5. Exhaust Connection a - Brown/White Wire to Insulated Terminal Figure 7. MCM 898/228/260 2E-10 - REMOVAL. INSTALLATION and ALIGNMENT 90-95693 485 13. Reconnect power steering fluid hoses as shown in Figure9. IMPORTANT: Bleed power steering system as outlined in "Stern Drive Service Manual". 14. Connect fuel line. Check for leaks. 15. Connect throttle cable. Refer to "Attaching/Adjusting Throttle Cable". 16. Connect any grounding wires or accessories that may have been disconnected. 17. Connect battery cables to battery. IMPORTANT: If stern drive unit was removed, refer to Step 14 in "Alignment". 15912 a - Brown/White Wire - Route Thru Clamps That Hold the Power Steering Hoses, Then Connect to Insulated Terminal Figure 8. MCM 898R/228R/260R Figure 9. Power Steering Connections ALIGNMENT BEARING SUPPORT INSTALLATION MCM 898R/228R/260R : Steps 1.2 and 3 MCM 898/228/260: Figure I The following procedure MUST BF. used when installing bear- ing support on MCM 898R/228R/260R Models. a - Bolt (2) b - Flat Washer (2) c - Spherical Washer (4) (Install with Rcunded Side 14760 Toward Bearing Support) a - Bolt (2) {Torque to Specifications) d - Bearing Support d - Bearing Support b-Spacer (2) e-Washer (2) e- Nut (2) c-Washer (2) f - Nut (2) Figure 2. Bearing Support Attaching Parts Figure 1. Bearing Support Attaching Parts 90-95693 485 REMOVAL, INSTALLATION and ALIGNMENT - 2E-11 1. Install bearing support, as shown in Figure 2. DO NOT tighten bolts. 2. Insert solid end of Alignment Tool (91-57797A3) thru bearing in gimbal housing and into input shaft splines. (Figure 3) 3. Tighten bearing support bolts until snug [5-10 lbs. ft. (7-13 .N.m)]. Strike the head of both bolts with a ball peen hammer, then torque bolts to specifications. a - Alignment Shaft Figure 3. Alignment Tool Installed IMPORTANT: Bearing support attaching bolts MUST BE struck with a hammer to properly seat spherical washers. If procedure is not followed, difficulty in installing stern drive unit may result and subsequent damage to bearings may occur from misalignment. ALIGNMENT IMPORTANT: A Sears Craftsman Universal Protractor (stock number 9-GT-3984) or equivalent is required for measuring the angles in the following steps. Protractor readings will be taken off of vertical and horizontal surfaces; therefore, both the 0° and the 90° marks will be used. It should be kept in mind that these are reference marks only and the actual numbers should be ignored. (Figure 4) It is only necessary to note the number of degrees and to which side (left or right) of the reference marks the indicator needle rests. PROTRACTOR MUST BE VIEWED FROM THE SAME SIDE OF POWER PACKAGE THROUGHOUT ALIGNMENT. Figure 4. Protractor Reference Marks 1. Insert solid end of alignment tool thru bearing in gimbal housing and into bearing support input shaft splines. (Figure 3) 2. Position base of protractor against input shaft flange, as shown in Figure 5. NOTE and RECORD the number of degrees and to which side of the reference mark the indicator needle has moved in the chart following. IMPORTANT: Be sure that boat does not move once reading has been taken from input shaft flange, as this reading establishes reference point for aligning drive shaft and engine following. 3. Lift engine into boat, using an overhead hoist and a chain (attached to lifting eyes on engine). When attaching drive shaft in next step. BE SURE that the pilot on drive shaft flanges are engaged in input shaft and output shaft flanges. Flanges MUST BE flush to each other prior to tightening screws, or screws may come loose during operation. 4. Attaching drive shaft to input shaft flange and output shaft flange, as shown in Figures 6 and 7. 5. Position base of protractor on drive shaft (Figure 8); then, adjust engine mounts so that indicator needle is 1° to 3° on either side of reading taken in Step 2. Record this reading in the following chart for later use. 2E-10 - REMOVAL. INSTALLATION and ALIGNMENT 90-95693 485 16284 IMPORTANT: A minimum of V«" (6mm) up-anddown engine mount adjustment must exist after engine has been properly aligned. This is necessary to allow for realignment of the engine in the future. If mount travel is insufficient, boat stringer height MUST BE adjusted. a - Output Shaft Flange b - Drive Shaft c - Screw (4 Used) (Torque to Specifications) d - Nut (4 Used) Figure 7. Drive Shaft Attached to Output Shaft Flange 16281 a - Input Shaft Flange b - Protractor c - Indicator Needle Figure 5. Measuring Angle of Input Shaft Flange a - Input Shaft Flange b - Drive Shaft c - Screw (4 Used) (Torque to Specifications) d - Nut (4 Used) Figure 6. Drive Shaft Attached to Input Shaft Flange 90-95693 485 a - Drive Shaft b - Protractor c - Output Shaft Flange Figure 8. Measuring Drive Shaft Angle IMPORTANT: Failure to properly position engine (as described following) may result in bearing damage. 6. Relieve hoist tension from engine, then slideengine fore or aft as needed to obtain a Vi" (6mm) between flange shoulder and extension shaft housing bearing, as shown in Figure 9. Engine MUST BE aligned correctly to achieve proper engine operation and to prevent damage to drive shaft. If drive shaft is run at an incorrect angle, damage to universal joint bearings may result. REMOVAL, INSTALLATION and ALIGNMENT - 2E-11 14765 14765 a - Flange Shoulder b - Bearing C - 1/4" (6mm) Figure 9. Distance Between Output Shaft Shoulder and Bearing 7. Position engine for correct engine and drive shaft lateral alignment as follows: a. The distance between the center of the bearing support attaching bolts (on inner transom plate) and grease fitting on shaft extension housing (Figure 10) MUST BE equal. If not, slide aft end of engine to one side or the other until distances are equal. b. Measure distance between the center of the bearing support attaching bolts and rear engine mount adjusting bolt, as shown in Figure 10. These distances also, MUST BE equal. If not, slide front of engine to one side or the other until distances are equal. 8. After engine has been aligned correctly, fasten front and rear engine mounts to stringers. 9. Position protractor on starter housing cover plate, as shown in Figure 11. Now, raise or lower front engine mount adjusting nuts as required so that protractor needle reads exactly the same number of degrees as that recorded in Step 2. 10. Position protractor on drive shaft (as shown in Figure 8) and recheck angle. Angle should be the same as that recorded in Step 5. If not, raise or lower all engine mount adjusting nuts an equal amount until correct angle is reached. a - Distance Between Bearing Support Attaching Bolts and Grease Fitting b - Distance Between Bearing Support Attaching Bolts and Engine Mount Bolts Figure 10. Engine Alignment 2E-10 - REMOVAL. INSTALLATION and ALIGNMENT 90-95693 485 16286 16286 a - Flywheel Housing b - Starter Housing Cover Plate c - Protractor Figure 11. Protractor Positioned Correctly on Starter Housing Cover Plate a - Top Shield b - Bottom Shield c - Screw (4 Used) d - Nut (4 Used) (Torque to Specifications) Figure 12. Top Shield Attached to Bottom Shield at Transom End 11. Tighten ALL engine mount locking nuts securely. 12. Remove alignment shaft from gimbal housing. 13. Install drive shaft shields. (Figures 12 and 13) a - Imaginary Centerline Running Thru This Universal Joint Bearing Must Be Vertical b - Place a Reference Mark Here To Correspond with "a" Figure 14. Aligning Drive Shaft Universal Joint 14. Install stern drive unit. Stern drive unit installation procedure is the sameas that for thestar.dard models, with the following exceptions: • No alignment is necessarv. other than to align gimbal bearing with bearing support input shaft. Steps 2 and 3. • Stern drive universal joints MUST BE aligned with drive shaft universal joints, as shown in Figures 14 and 15. Place a reference mark (white paint) on shafts to correspond with universal joint centerlines. After installing stern drive, check to ensure that these marks are in alignment. 16300 a - Top Shield b - Bottom Shield c - Screw (4 Used) d - Nut (4 Used) (Torque to Specifications) Figure 13. Top Shield Attached to Bottom Shield at Engine End 16502 90-95693 485 REMOVAL, INSTALLATION and ALIGNMENT - 2E-11 a - Imaginary Centerline Running Thru This Universal Joint Bearing Must Be Vertical (Once Drive Unit Is Installed) b - Place a Reference Mark Here To Correspond with "a" Figure 15. Aligning Stern Drive Unit Universal Joints ATTACHING/ADJUSTING THROTTLE CABLE 1. Place remote control in neutral gear, idle position. 2. Fasten cable end guide as shown in Figure 1 or 2. 3. Grasp throttle cable brass barrel and push cable lightlv toward throttle lever. Adjust barrel to align with anchor stud. Fasten barrel as shown in Figure 1 or 2. 4. Check that throttle valves are fully open when remote control is at full throttle position. Lever tang should be against stop as shown in Figure 3 or 4. 5. Return remote control to neutral gear, idle position. Check that idle stop screw is against stop. (Figure 1 or 4) a - Cable End Guide e - Brass Barrel b - Bushing f - Washer and Nut (DO NOT Over-Tighten) c - Washer. Nut and Screw (DO NOT Over-Tighten) d - Spacer g - Anchor Stud Figure 2. MCM 228/228R/260/260R a - Cable End Guide 15804 b - Washer. Nut. Screw and Bushing (DO NOT Over-Tighten) c - Brass Barrel d - Stud e - Washer and Nut (DO NOT Over-Tighten) f - Idle Stop Screw Figure 1. MCM 898/898R 2E-10 - REMOVAL. INSTALLATION and ALIGNMENT 90-95693 485 17302 17302 a - Tang a - Throttle Lever Tang Against Stop b - Carburetor Body Figure 3. MCM 898/898R c - Idle RPM Adjustment Screw Figure 4. MCM 228/228R/260/260R 90-95693 485 REMOVAL, INSTALLATION and ALIGNMENT - 2E-11 SECTION 2 - REMOVAL, INSTALLATION and ALIGNMENT PART F - MCM 330TR/TRS WITH MERCURY MARINE TRANSMISSION INDEX Page Torque Specifications 2F-1 Tools/Lubricants 2F-1 Removal 2F-2 Installation/Alignment 2F-2 Attaching Electric Shift Control 2F-5 Attaching/Adjusting Mechanical Shift Cable 2F-6 Attaching/Adjusting Throttle Cable 2F-7 TORQUE SPECIFICATIONS Fastener Location Lbs. Ft. (N.m) Lbs. In. (N.m) Battery Cables Securely Front Engine Mount Securely Hose Clamps Securely Powe PowePowe r rr Steerin SteerinSteerin g gg Flui FluiFlui d dd Hos HosHos e ee Fitting FittingFitting s ss Larg LargLarg e ee 20-25 (27-34) Smal SmalSmal l ll 96-108 (11-12) Rear Engine Mount Compression Nuts 70 (8) Remot RemotRemot e ee Contro ControContro l ll Shif ShifShif t tt Cabl CablCabl e ee Bras BrasBras s ss Barre BarreBarre l ll 60-70 (7-8) Cabl CablCabl e ee En EnEn d dd Guid GuidGuid e ee 60-70 (7-8) Remot RemotRemot e ee Contro ControContro l ll Throttl ThrottlThrottl e ee Cabl CablCabl e ee Bras BrasBras s ss Barre BarreBarre l ll Securely Cabl CablCabl e ee En EnEn d dd Guid GuidGuid e ee (Note 1) NOTE 1: Tight, then back nut off 1/2 turn. TOOLS/LUBRICANTS TOOLS/LUBRICANT S 91-57797A3 Engine Alignment Tool 92-86154A1 Quicksilver 2-4-C Multi-Lube 90-95693 485 REMOVAL, INSTALLATION and ALIGNMENT -2E-1 REMOVAL NOTICE Stern drive unit must be removed prior to engine removal. Refer to "Stern Drive Service Manual." 1. Loosen 6 transmission output housing rear mount nuts. (Figure 1) 07449 2. Disconnect battery cables from battery and remove instrument harness connector plug from engine harness receptacle. 3. Disconnect fuei line and throttle cable. 4. Kleclric Shift Models: Remove electric shift wiring harness from terminal block (located on transmission). Mechanical Shift Models: Remove shift cable. 5. Remove rec and black Power Trim pump motor wires from engine (some models). 6. Disconnect water inlet hose and exhaust elbow bellows. T. Disconnect fluid hoses from power steering control valve. 8. Remove Pcwer Trim hoses from reverse lock located on transmission (some models). 9. Disconnect trim position sender wires from terminal block located on engine. 10. Disconnect anv grounding wire or accessories that are connected lo the engine. IMPORTANT: DO NOT lift engine until rear mount is disengaged from gimbal housing. 1 1. Support engine with a suitable sling thru lifting eyes on engine and remove engine front mounting bolts. 12. Pull engine forward to disengage rear engine mount from gimbal housing and carefullv remove engine. a-Nuts (6) Figure 1. Rear Mounting Nuts INSTALLATION/ALIGNMENT 1. Coat rubber rear mount (Figure 1) and gimbal housing opening (Figure 2) with 2-4-C Multi-Lube. a - 2-4-C Multi-Lube Figure 2. Gimbal Housing Opening IMPORTANT: Make sure that 6 nuts on transmission output housing are loose before installing. (Figure 1) a - 2-4-C Multi-Lube b - Nuts (6) Figure 1. Rubber Rear Mount 90-95693 435 2F-2 - REMOVAL. INSTALLATION and ALIGNMENT 2. Lift engine with an overhead hoist, using suitable sling and lifting eyes on engine. 3. Position engine ahead of inner transom plate so that transmission output housing (Figure 1) is in line with large opening in inner transom plate. (Figure 2) 4. Move engine toward inner transom plate and, at the same time, guide transmission output housing into gimbal housing opening until output housing bottoms-out on shoulder in gimbal housing. Be careful that transmission output housing and rubber mount do not become damaged. CAUTION Transmission output housing MUST BOTTOMOUT on SHOULDER in gimbal housing or exhaust elbow misalignment will result, with subsequent damage to exhaust system. 5. Relieve hoist tension, as required, to allow transmission output housing to seat in gimbal housing. IMPORTANT: Do not relieve hoist tension entirely at this time, as transmission and output housing may be damaged. 6. Position alignment tool plate on shaft, as shown in Figure 3. Thread extension onto alignment shaft, insert end of alignment tool into opening in bell housing and ir.to transmission output housing. (Figure 3) Insert shaft until it bottoms-out in transmission output housing. 7. Slide plate toward bell housing. Raise or lower front of engine with hoist to allow shoulder on plate to enter bell housing opening. (Figure 4) Figure 4. Tool Plate Installed 8. With alignment tool plate positioned in bell housing and engine supported with hoist, front engine mount supports should be constructed so that mounts will rest on top of supports without disturbing alignment tool plate position when hoist tension is relieved. IMPORTANT: Engine alignment should be near to correct before front engine mounts are fastened to engine bed. Only small adjustment should be necessary in following procedure. 9. Relieve hoist tension entirely and fasten front mounts (with slotted mounting hole toward front of engine) to engine bed. IMPORTANT: Steering link rod must be disconnected before proceeding with engine alignment. Reconnect after alignment is completed. 10. Push alignment shaft and plate toward engine and, while holding plate against bell housing, check for gap between plate and rear surface of bell housing at 12, 3, 6 and 9 o'clock positions. Engine alignment is correct when there is no gap at any point. If gap exists, proceed as follows: Figure 3. Alignment Tool Location 90-95693 485 REMOVAL, INSTALLATION and ALIGNMENT - 2E-11 GAP AT 12 O'CLOCK POSITION Raise front of engine. Loosen locking nuts (Figure 5) and turn adjusting nuts counterclockwise. Turn adjusting nuts (on both front mounts) an equal amount by alternating from one side to the other until gap no longer exists. Retighten locking nuts securely. 11432 a - Locking Nut b - Adjusting Nut c - Slotted Hole Figure 5. Front Engine Mounts GAP AT 6 O'CLOCK POSITION Lower front of engine. Loosen locking nuts (Figure 5) and turn adjusting nuis clockwise. Turn adjusting nuts (on both front mounts) an equal amount by alternating from one side to the other until gap no longer exists. Retighten locking nuts securely. GAP AT 3 O'CLOCK POSITION Loosen lag screws which attach mounts to engine bed. Move engine to the right (starboard), using adjustment slot (Figure 5). until gap no longer exists. Retighten engine mount to engine bed lag screws securely. GAP AT 9 O'CLOCK POSITION Loosen lag screws which attach mounts to engine bed. Move engine to the left (port), using adjustment slot (Figure 5), until gap no longer exists. Retighten engine mount to engine bed lag screws securely. 11. After correct alignment has been attained, re-check all mount fasteners to be sure that they are tight. 12. Remove alignment shaft and plate. (Shaft should remove easilv.) 13. Torque 6 rear mount compression stud nuts to specifications. (Figure 6) 2E-4 - REMOVAL. INSTALLATION and ALIGNMENT a - Compression Nuts (6) - Torque to Specification Figure 6. Rear Engine Mount 14. Retighten bellows clamps on exhaust manifold eibow> (both sides). 15. Connect water inlet hose to seawater pump. Tighten clamp securely. 16. Connect instrument harness to engine harness. Secure with clamp and tighten securely. 17. Connect red and black Power Trim pump wires to engine (some models). 18. Connect fuel line. Check for leak>. 19. Connect trim position sender wires to terminal block on engine. (Purple or brown sleeve wire to insulated terminal, black wire to block mounting screw.) 20. Connect anv ground wires or accessories thai ma\ have been disconnected. 21. Power Steering Models: Reconnect fllaid hoses as shown in Figure 7. IMPORTANT: Bleed power steering system as outlined in "Stern Drive Service Manual ". Figure 7. Power Steering Connections 90-95693 485 22. Connect Power Trim hoses to reverse lock valve as shown in Figure 8. (Some models.) 10356 23. For shift and throttle connections, refer to the following: • "Attaching Electric Shift Control" • "Attaching/Adjusting Mechanical Shift Cable" • '"Attaching/Adjusting Throttle Cable" 24. Connect battery cables to battery. a - Reverse Lock b - Gray Hose from Transom Plate c - Plastic Hose from Trim Pump Figure 8. Reverse Lock Connections ATTACHING ELECTRIC SHIFT CONTROL IMPORTANT: Battery cables must be disconnected from battery prior to connecting shift control wiring to shift motor. 1. Remove shift motor cover. Shift harness wires are color-coded and MUST BE attached to terminals of same color on shift motor terminal block. If not connected correctly, transmission failure will occur. (Figure 2) 2. Connect ring terminals (located on shift control harness) to terminals on shift motor, matching lead and terminal colors. Fasten harness clamp to shift motor bracket. (Figure 1) Reinstall cover. Figure 2. 07505 a - Terminal Block b - Harness Clamp c - Remote Control Harness Figure 1. Harness Connection 90-95693 485 REMOVAL, INSTALLATION and ALIGNMENT - 2E-11 ATTACHING/ADJUSTING MECHANICAL SHIFT CABLE Remote control shift cable end guide musl retract when remote control is shifted into forward gear or transmission failure will occur. (Figure 1) Insufficient shift cable travel or improper adjustment may prevent transmission from being fully shifted into gear, which could cause forward clutch packand/or reverse clutch band to fail. Remote control shift cable must have minimum travel as shown in Figure 1 from full forward to full reverse. Transmission shift rod assembly is preset to dimension shown in Figure 2 and MUST NOT be changed. Check dimension to ensure that it has not been changed. a - 2-13/16" (72mm) Minimum, 3" (76mm) Ideal b - Forward Gear c - Reverse Gear Figure 1. Shift Cable Travel a - 5-1/32" (128mm) Figure 2. Transmission Shift Rod Dimension Adjust Remote Control shift cable as follows: 1. Place remote control lever in neutral position. 2. While holding barrel, move remote control shift cable end guide in both directions to determine limits of end play. Position end guide at mid-travel position. 3. While maintaining end guide at mid-travel position, adjust shift cable barrel as follows: Without Shift Cable Adjusting Tool (Figure 3): Adjust shift cable barrel until the center of the barrel is exactly 7!/s" (181mm) from the center of the hole in the cable end guide. Willi Shift Cable Adjusting Tool (Figure 3): a. Place Adjusting Tool on studs and reinstall spacer on anchor stud. b. Adjust shift cable barrel to align attaching holes with studs. c. Remove Adjusting Tool from studs. 4. Being careful not to disturb barrel adjustment, install cable on studs and secure with flat washer, spacer and elastic stop nuts. Torque nuts to specifications. MOTE: An Adjusting ToolMerCruiser TR. TRS PowerConversion Kit and is giveninstallation. Obtain tool fromlowing adjustment. This toolDepartment. is shipped with each new Package and Mechanical Shift to the boat owner after initial boat owner to perform the folis not available from our Service 2E-10 - REMOVAL. INSTALLATION and ALIGNMENT 90-95693 485 a - 7-1/8" (181mm) b - Shift Adjustment Tool Figure 3. Adjusting Shift Cable Barrel ATTACHING/ADJUSTING THROTTLE CABLE 1. Place remote control in neutral gear, idle position. 2. Fasten cable end guide as shown in Figure 1. 3. Grasp throttle cable brass barrel and push cable lightly toward throttle lever. Adjust barrel to align with anchor stud. Fasten barrel as shown in Figure 1. a - Tang b - Carburetor Body c - Idle RPM Adjustment Screw Figure 2. Idle/Full Throttle Check a - Bushing (Hidden) d - Screw h - Nut and Washer b - Nut and Washer e - Throttle Lever (DO NOT Over( DO NOT Over-f- Cable End Guide Tighten) 4. Check that throttle valves are fully open when remote Tighten) g - Brass Barrel i - Anchor Stud c - Spacer j - Spacer (Hidden) control is in full throttle position. (Figure 2) 5. Return remote control to neutral gear, idle position. Check Figure 1. Throttle Cable Installed that idle stop screw is against stop. (Figure 2) 90-95693 485 REMOVAL, INSTALLATION and ALIGNMENT - 2E-7 SECTION 2 - REMOVAL, INSTALLATION and ALIGNMENT PART G - MCM 330 (B-W) TR/TRS INDEX Page Torque Specifications 2G-1 Tools/Lubricants 2G-1 Removal 2G-2 Installation/Alignment 2G-3 Attaching/Adjusting Shift Cable 2G-6 Attaching/Adjusting Throttle Cable 2G-7 TORQUE SPECIFICATIONS Fastener Location Lbs. Ft. (N.m) Lbs. In. (N.m) Battery Cables Securely i Front Engine Mount Securely iI Hose Clamps Securely Powe PowePowe r rr Steerin SteerinSteerin g gg Flui FluiFlui d dd Hos HosHos e ee Fitting FittingFitting s ss Larg LargLarg e ee 20-25 (27-34) Smal SmalSmal l ll 96-108 (11-12) Rear Engine Mount 100 (136) Remot RemotRemot e ee Contro ControContro l ll Shif ShifShif t tt Cabl CablCabl e ee Bras BrasBras s ss Barre BarreBarre l ll (Note 1) Cabl CablCabl e ee En EnEn d dd Guid GuidGuid e ee (Note 1) Remot RemotRemot e ee Contro ControContro l ll Throttl ThrottlThrottl e ee Cabl CablCabl e ee Bras BrasBras s ss Barre BarreBarre l ll (Note 1) Cabl CablCabl e ee En EnEn d dd Guid GuidGuid e ee (Note 1) NOTE 1: Tight, then back nut off 1/2 turn. TOOLS/LUBRICANTS TOOLS/LUBRICANT S 91-57797A3 Engine Alignment Tool 92-86154A1 Quicksilver 2-4-C Multi-Lube 90-95693 485 REMOVAL, INSTALLATION and ALIGNMENT -2E-1 REMOVAL NOTICE Stern drive unit must be removed prior to engine removal. Refer to "Stern Drive Service Manual." 1. Disconnect battery cables from battery and remove instrument harness connector plug from engine harness receptacle. 2. Disconnect fuel line and throttle cable. 3. Disconnect trim position sender vires from terminal block on flywheel housing. 4. Disconnect water inlet hose and exhaust elbow bellows. 5. Remove shift cable. 6. Remove buzzer tan/blue wire from water heat switch in thermostat housing. 7. Disconnect any grounding wire or accessories that are connected to the engine. 8. Power Steering Models: Disconnect fluid hoses from power steering control valve. 9. Support engine with suitable sling thru lifting eyes on engine and remove front and rear engine mounting bolts. 10. Pull engine forward to disengage transmission output housing from gimbal housing and carefully remove engine. 2E-2 - REMOVAL. INSTALLATION and ALIGNMENT 90-95693 485 INSTALLATION/ALIGNMENT 1. Prepare (ransom assembly as shown in Figure 1. a - Transom Gi"nbal Housing Assembly Opening (Lubricate with 2-4-C Multi-Lube) b - Double-Wound Lockwasher (2) c - Fiber Washer (2) d - Large Steel Washer (2) e - Engine Supports Figure 1. Preparing Transom Assembly Prepare transmission output housing as show n in Figure 2. 15504 a - Transmission Output Housing b - "O" Ring Seal (Lubricate with 2-4-C Multi-Lube) Figure 2. Transmission Output Housing 3. Lift engine with an overhead hoist, using a suitable sling and lifting eyes on engine. 4. Position engine ahead of inner transom plale so that transmission output housing (Figure2) is in line with large opening in inner transom plate, (figure l) IMPORTANT: Take care when installing engine in next step to prevent damage to "O" ring seal on transmission output housing. 5. Carefully guide transmission output housing into transom gimbal housing assembly until holes in r^ar engine mounts align with holes in inner transom plate engine supports. IMPORTANT: DO NOT relieve hoist tension en tirely, as inner transom plate engine supports and/ or transmission output housing may be damaged. 6. Relieve hoist tension, as required, to allow rear engine mounts to rest on inner transom plate engine supportsand washers. 7. Secure rear engine mounts as shown in Figure 3. Torque bolts to specifications. a - Bolt b - Steel Washer c - Fiber Washer d - Rear Engine Mount e - Inner Transom Plate Engine Support f - Elastic Stop Nut Figure 3. Securing Starboard and Port Rear Engine Mounts 90-95693 485 REMOVAL, INSTALLATION and ALIGNMENT - 2E-3 Figure 5. Engine Alignment Tool Plate in Position 2E-4 - REMOVAL. INSTALLATION and ALIGNMENT 9. With alignment tool plate positioned in bell housing and 8. Insert solid end of Alignment Tool thru bell housing hore engine supported with hoist, front engine mounts should and into transmission output housing until it bottoms. rest on top of stringers without disturbing alignment tool (Figure 4) Slide plate toward bell housing and position bell plate position when hoist tension is relieved. housing, as required, to allow shoulder on plate to enter bell housing bore. (Figure 5) NOTE : Boat stringers must position engine so that a minimum of '/*" (6mm) of up-and-down front mount adjustment exists after mounts are lowered onto stringers. 10. Relieve hoist tension entirely and fasten front engine mounts (with slotted mounting hole toward front of engine) to stringers. (Figure 6) Figure 4. Engine Alignment Tool Installed a-Locking Nut e - Front Mount b - Lockwasher f - Slot (Must Be Forward) c - Front Mount Bracket g - Lag Bolts d - Adjusting Nut Figure 6. Engine Mount Secured to Boat Stringer 11. W hile pushing in on alignment shaft and plate, check for gap between plate and bell housing rear surface at 12. 6. 3 and 9 o'clock positions. Kngine alignment is correct when no gap exists at anv position. If a gap exists, proceed as follows (Figure 6): GAP AT 12 O'CLOCK POSITION Loosen locking nuts on front engine mounts. BOTH mounts ML ST BK adjusted equallv to keep engine level from side to side. Turn adjusting nut on both mounts equallv ccunterclockwise to raise front of engine, until no gap exists Tighten locking nuts securelv (until lockwasher is compressed). GAP AT 6 O'CLOCK POSITION Loosen locking nuts on front engine mounts. BOTH mounts MUST BL adjusted equallv to keep engine level from side to side. Turn adjusting nut on both mount* equallv clockwise to lower front of engine, until no gap exists. Tighten locking nuts securelv (until lockwasher is compressed). 90-95693 485 GAP AT 3 O'CLOCK POSITION Loosen lag bolls which fasten front engine mounts to boat stringers and move engine to the right (starboard) until no gap exists. Retighten lag bolts securely. GAP AT 9 O'CLOCK POSITION Loosen lag bolts which fasten front engine mounts to boat stringers and move engine to the left (port) until no gap exists. Retighten lag bolts securely. 12. After correct alignment has been attained, re-check all mount fasteners to be sure that they are tight. 13. Remove alignment shaft and plate. 14. Retighten bellows clamps on exhaust manifold elbows (both sides). 15. Connect water inlet hose to seawater pump. Tighten clamp securelv. 16. Connect instrument harness to engine harness. Secure with clamp and tighten securelv. 17. Connect fuel line. Check for leaks. 18. Connect trim position sender wires as shown in Figure 7. 15497 a - Flywheel Housing b - Terminal Block Mounting Screw c - Wire without Purple or Brown Sleeve d - Insulated Terminal e - Wire with Purple or Brown Sleeve f - Brown/White Wire Figure 7. Trim Position Sender Wires Connected to Terminal Block Figure 9. Power Steering Connections 19. Connect tan/blue buzzer wire as shown in Figure a - Cooling System Water Heat Switch b - Tan/Blue Wire (From Oil Pressure Switch) c - Tan/Blue Wire From Buzzer Figure 8. Tan/Blue Buzzer Wire Connection 20. Connect any ground wires or accessories that may have been disconnected. 21. Pow er Steering Models: Reconnect fluid hoses as shown in Figure 9. IMPORTANT: Bleed power steering system as outlined in "Stern Drive Service Manual". 22. For shift and throttle connections, refer to the following: • "Attaching/Adjusting Shift Cable" • "Attaching/Adjusting Throttle Cable" 23. Connect batterv cables to batterv. 1555 7 90-95693 485 REMOVAL, INSTALLATION and ALIGNMENT - 2E-11 ATTACHING/ADJUSTING SHIFT CABLE 1. Place remote control shift lever in neutral position. 2. Place transmission shift lever in neutral position, indicated when poppet ball (located behind shift lever) is in center detent hole of shift lever. (Figure 1) 15508 a - Shift Lever b - Poppet Ball In Center Hole of Shift Lever Figure 1. Neutral Position 3. Adjust brass barrel on shift cable, as required, to align shift cable attaching holes with shift cable lever and shift cable anchor studs. Center the cable end play travel when making adjustment. 4. Install shift cable and secure with flat washers and elastic stop nuts. (Figure 2) Tighten nuts to specifications. 5. Place remote control shift lever in full forward gear position. Check position of transmission shift lever. Transmission shift lever MUST BE positioned so that the poppet ball is in rear detent hole of shift lever. (Figure 3) a - Shift Lever b - Poppet Ball In Rear Detent Hole c - "F" On Transmission Case Figure 3. Forward Gear Position 6. Place remote control lever in full reverse gear position and. again, check transmission shift lever position. Poppet ball MUST BE in front detent hole of shift lever. (Figure 4) 7. If transmission shift lever is positioned correctly in one gear (forward or reverse), but not in the other, recheck shift cable adjustment. If transmission shift lever is not positioned properlv in both gears, move shift rod stud from top hole in transmission shift lever to bottom hole (Figure 4) and recheck for proper positioning of shift lever. If proper positioning is still not obtained, remote control does not provide sufficient shift cable travel and MUST BE replaced. Remote control and shift cable MUST position transmission shift lever so that it is fully in the forward and reverse gear detent position and over the letter "F" on transmission case when propelling boat forward. TRANSMISSION SHIFT LEVER MUST BE POSITIONED PROPERLY (WITHOUT ANY MODIFICATION TO TRANSMISSION) OR TRANSMISSION FAILURE MAY OCCUR. Warner Gear Warranty is jeopardized if the shift lever poppet ball or spring is permanently removed; if the shift lever is repositioned or changed in any manner; or remote control and cable do not position shift lever correctly. a - Lever Stud d-Anchor Stud b - Washer and Nut e - Washer and Nut c - Cable End Guide f - Brass Barrel Figure 2. Shift Cable Installed 2E-10 - REMOVAL. INSTALLATION and ALIGNMENT 90-95693 485 15509 15509 a - Shift Lever b - Poppet Ball In Front Detent Hole c - "FT On Transmission Case d - Install Shift Rod Stud in This Hole. If Necessary. To Properly Position Shift Lever With Poppet Ball Figure 4. Reverse Gear Position ATTACHING/ADJUSTING THROTTLE CABLE 1. Place remote control in neutral gear, idle position. 2. Fasten cable end guide as shown in Figure 1. 3. Grasp throttle cable brass barrel and push cable lightly toward throttle lever. Adjust barrel to align with anchor stud. Fasten barrel as shown in Figure 1. a - Anchor Stud b - Washer and Nut (DO NOT Over-Tighten) c - Brass Barrel d - Cable End Guide e - Spacer f - Screw g - Washer and Nut (DO NOT Over-Tighten) h - Bushing Figure 1. Throttle Cable Installed a - Tang b - Carburetor Body c - idle RPM Adjustment Screw- Figure 2. Idle/Full Throttle Check 4. Check that throttle valves are fullv open when remote control is in full throttle position. (Figure 2) 5. Return remote control to neutral gear, idle position. Check that idle stop screw is against stop. (Figure 2) 90-95693 485 REMOVAL, INSTALLATION and ALIGNMENT - 2E-11 SECTION 2 - REMOVAL, INSTALLATION and ALIGNMENT PART H - MCM 370/400 TRS and HI-PERFORMANCE ENGINES INDEX Page Torque Specifications 2H-1 Tools/Lubricants 2H-1 Notice 2H-2 Removal 2H-2 Removal/Installation of Driveshaft and Tail- stock Housing (Engines with Driveshaft) 2H-3 Removal 2H-3 Installation 2H-4 Installation/Alignment 2H-5 Transom Mounted Engine 2H-5 Engine with Driveshaft 2H-7 Completing Installation 2H-7 Attaching/Adjusting Shift Cable 2H-8 Models with Reverse Lock Valve 2H-8 Models without Reverse Lock Valve 2H-9 Attaching/Adjusting Throttle Cable 2H-11 TORQUE SPECIFICATIONS Fastener Location Lbs. Ft. (N.m) Lbs. In. (N.m) Battery Cables Securely Driveshaft to Tailstock Flange 50 (68) (Note 2) Driveshaft to Transmission Output Flange 35 (48) Front Engine Plate Mount Securely Hose Clamps Securely Powe PowePowe r rr Steerin SteerinSteerin g gg Flui FluiFlui d dd Hos HosHos e ee Fitting FittingFitting s ss Larg LargLarg e ee Smal SmalSmal l ll 20-25 (27-34) 96-108 (11-12) Rear Engine Mounts (Transom Mounted Engine) 100 (136) Rear Engine Plate Mount Securely Remot RemotRemot e ee Contro ControContro l ll Shif ShifShif t tt Cabl CablCabl e ee Bras BrasBras s ss Barre BarreBarre l ll Cabl CablCabl e ee En EnEn d dd Guid GuidGuid e ee (Note 1) (Note 1) Remot RemotRemot e ee Contro ControContro l ll Throttl ThrottlThrottl e ee Cabl CablCabl e ee Bras BrasBras s ss Barre BarreBarre l ll Cabl CablCabl e ee En EnEn d dd Guid GuidGuid e ee (Note 1) (Note 1) Tailstock Housing Compression Nuts 70(8) Tailstock Mounts 100 (136) NOTES: 1. Tight, then back nut off 1/2 turn. 2. Secure with safety wire. TOOLS/LUBRICANTS TOOLS/LUBRICANT S 91-57797A3 Engine Alignment Tool 92-86154A1 Quicksilver 2-4-C Mjlti-Lube 90-95693 485 REMOVAL, INSTALLATION and ALIGNMENT -2E-1 NOTICE This section contains repair procedures primarily lor MCM 370/400 TRS models It can be used as a guide for the Hi- Performance models listed, however. Mercurv Marine can not possiblv list the differences between each model. MCM 100 Cyclone TRS MCM 460 Cyclone TRS MCM 440 Cyclone TRS MCM 475 Turbo TRS II SSM and 111 SSM Models: Engine removal and installation is basically the same as TRS models. REMOVAL NOTICE Stern drive unit must be removed prior to engine removal. Refer to "Stern Drive Service Manual." 1. Disconnect batterv cables from batterv and remove instrument harness connector plug from engine harness receptacle. 2. Disconnect fuel line and throttle cable. 3. Disconnect trim position sender wire (some models). 4. Remove red and black Power Trim pump motor w ires from engine (some models). 5. Disconnect water inlet hose and exhaust system. 6. Remove shift cable. 7. Disconnect anv grounding wire or accessories that are connected to the engine. 8. Power Steering Model*: a. fluid Cooler Mounted on Engine: Disconnect fluid hoses from power steering control valve. b. Fluid Cooler Mounted on Stringer: Disconnect fluid hoses from cooler. 9. Models with Transmission Oil Cooler Mounted on Stringer: Disconnect oil hoses from cooler. Mark location each hose was removed from. 10. Models with Engine Oil Cooler Mounted on Stringer: Disconnect oil hoses from cooler. Mark location each hose was removed from. 11. Disconnect hvdraulir hoses from reverse lock val\e located on transmission (some models). 12. Support engine with suitable sling thru lifting eves on engine and remove front and rear engine mounting bolts. 13. Transom Mounted Engine: Pull engine forward to disengage transmi?sion output housing from gimbal housing and carefullv remove engine. a - Transmission Output Shaft b - Driveshaft c - U-Bolts (2) d - Elastic Stop Nuts (4) e - Splines f - Make Alignment Marks With Paint Figure 1. Driveshaft Models Driveshaft has been assembled and balanced at the factory with the universal joint yoke on both ends of shaft running in the same plane. If it is necessary to remove splined end of shaft, end MUST BE reinstalled in splines in exactly the same position as factory assembled, or damage to universal joints and driveshaft may result. 14. Engine with Driveshaft: Method \: Mark driveshaft in two locations as shown in Figure 1. Pull engine forward to disengage driveshaft splines and carefullv remove engine. Method B: Disconnect driveshaft from transmission output shaft as shown in Figure 1. Carefully remove engine. 2H-2 - REMOVAL. INSTALLATION and ALIGNMENT 90-95693 485 REMOVAL/INSTALLATION OF DRIVESHAFT and TAILSTOCK HOUSING (ENGINES WITH DRIVESHAFT) REMOVAL 1. Disconnect both ends of driveshaft as shown in Figures 1 Driveshaft has been assembled and balanced and 2. at the factory with the universal joint yokes on both end of shaft running in the same plane. If it is necessary to remove splined end of shaft, mark driveshaft in two locations as shown in Figure 1. Driveshaft splines must be aligned in exactly the same position as factory assembled, or damage to universal joints and driveshaft may occur. 2. Remove driveshaft. 3. Loosen tailstock compression nuts. (Figure 3) a - Remove 4 Nuts b - Remove 2 U-Bolts c - Make Alignment Marks With Paint Figure 1. Engine End a - Compression Nuts b - Bell Housing Figure 3. Loosen Compression Nuts 4. Remove tailstock housing to inner transom plate support fasteners. 5. Remove tailstock housing from opening in gimbal housing. a - Cut Safety Wire b - Remove 4 3olts and Washers Figure 2. Tailstock End 11956 90-95693 485 REMOVAL, INSTALLATION and ALIGNMENT - 2E-11 INSTALLATION 1. Lubricate rubber "0 " ring seal on tailstock housing assemblv (Figure 4) and opening in gimbal housing (Figure 5) with 2-4-C Multi-Lube. a - Mounting Bolt (2) c - Elastic Stop Nut (2) b - Large Steel Washers (4) d - Inner Transom Plate Support (2) Figure 6. Tailstock Housing Installed 4. Torque 6 tailstock housing "0 " ring seal compression nuts (Figure 3) to specifications. 11953 a - "O" Ring Seal (Lubricate with 2-4-C Multi-Lube) b - Compression Nuts (6) Figure 4. Tailstock Housing Assembly 2. If not alreadv done, loosen tailstock housing compression nuts. (Figure 4) 3. Insert tailstock housing assemblv into gimbal housing opening until holes in housing align with holes in inner transom plate supports. Secure tailstock housing to inner transom plate supports with bolts, flat washers and elastic stop nuts, as shown in Figure 6. Torque to specifications. Drive shaft has been assembled (and balanced) at the factory with the universal joint yokes on both ends of shaft running in the same plane. If it is necessary to remove splined end of shaft, end MUST BE reinstalled in splines in exactly the same position as factory assembled, or damage to universal joints and drive shaft may result. 5. Attach driveshaft to tailstock housing flange with boltsand a - Gimbal Housing Opening (Lubricate with 2-4-C Multi-Lube) Figure 5. Gimbal Housing Opening washers. Torque to specifications. 6. Secure bol'.s with stainless steel safetv wire, being sure to install wire in such a manner that it does not loosen bolts. (Figure 2) If bolts do not have hole in head forsafety wire. drill as shown in Figure 7. a - 1/16" (2mm) Dia. Hole Figure 7. Drilling Bolts 7. Attach driveshaft to transmission output shaft with I -bolt? and elastic stop nuts. Torque to specifications. 8. Install engineas outlined under "Installation/ Alignment . 2E-4 - REMOVAL. INSTALLATION and ALIGNMENT 90-95693 485 INSTALLATION/ALIGNMENT TRANSOM MOUNTED ENGINE 1. Prepare transom assemblv as shown in Figure ]. a - Giribal Housing Opening (Lubricate with 2-4-C Multi-Lube) b - Double-Wound Lockwasher (2) c - Fiber Washer (2) d - Large Steel Washer (2) e - Engine Supports Figure 1. Preparing Transom Assembly Prepare transmission output housing as shown in Figure2. a - Transmission Output Housing b - "O" Ring Seal (Lubricate with 2-4-C Multi-Lupe) Figure 2. Transmission Output Housing 3. Lift engine with an overhead hoist, using a suitable sling and lifting eyes on engine. 4. Position engine ahead of inner transom plate so that transmission output housing (Figure 2) is in line with large opening in inner transom plate. (Figure 1) IMPORTANT: Take care when installing engine in next step to prevent damage to "O" ring seal on transmission output housing. 5. Carefullv guide transmission output housing into transom gimbal housing assembly until holes in rear engine mounts align with holes in inner transom plate engine supports. IMPORTANT: DO NOT relieve hoist tension en tirely, as inner transom plate engine supports and/ or transmission output housing may be damaged. 6. Relieve hoist tension, as required, to allow rear engine mounts to rest on inner transom plate engine supports and washers. 7. Insert mounting bolts up thru inner and rear mounts as shown in Figure 3. Torque to specifications. 11749A a - Elastic Stop Nut d - Bolt b - Steel Washer e - Rear Engine Mount c - Fiber Washer Figure 3. Securing Rear Engine Mounts 8. Insert solid end of Alignment Tool thru bell housing bore and into transmission output housing until it bottoms. (Figure4) Slide plate toward bell housingand position bell housing, as required, to allow shoulder on plate to enter bell housing bore. (Figure 5) 90-95693 485 REMOVAL, INSTALLATION and ALIGNMENT - 2E-5 Figure 4. Engine Alignment Tool Installed 15908 9. While pushing in on alignment shaft and plate, check for gap between plate and bell housing rear surface at 12, 3, 6 and 9 o'clock positions. Engine alignment is correct when no gap exists at any position. If a gap exists, proceed as fol low's: Gap at 12 o'clock Position Raise front of engine with hoist, as required, until gap no longer exists. Gap at 6 o'clock Position Lower front of engine with hoist, as required, until gap no longer exists. Gap at 3 o'clock Position Move engine to the right (starboard) until gap no longer exists. Gap at 9 o'clock Position Move engine to the left (port) until gap no longer exists. 10. After correct alignment has been attained, fasten front plate mount to angle irons. Tighten fasteners securely. Engine with rear plate mount: Fasten rear plate mount to angle irons. Tighten fasteners securely. 11. After engine has been fastened securely to boat, recheck engine alignment to ensure that engine has not moved: then remove alignment tool. 12. Refer to "Completing Installation". Figure 5. Engine Alignment Tool Plate in Position 2E-10 - REMOVAL. INSTALLATION and ALIGNMENT 90-95693 485 ENGINES WITH DRIVESHAFT 1. If removed, install (ailslock housing to inner transom plate as outlined. 2. If removed, install driveshaft to flange on tailstock housing as outlined. 3. Attach a suitable sling to lifting eyes on engine and lift engine into boat. Position engine in its approximate mounting location. 4. Method A: Attach drive shaft to transmission output shaft with L -bolts and elastic stop nuts. (Figure 6) Torque nuts to specifications. Method B: Align painted alignment marks on each half of driveshaft and slide splined shafts together. (Figure 6) Driveshaft has been assembled (and balanced) at the factory with the universal joint yoke on both ends of shaft running in the same plane. If it is necessary 1o remove splined end of shaft, end MUST BE reinstalled in splines in exactly the same position as factory assembled, or damage to universal joints and driveshaft may result. a - Transmission Output Shaft b - Driveshaft c- U-Bolts (2) d - Elastic Stop Nuts (4) e - Splines f - Painted Alignment Marks Figure 6. Driveshaft Attached to Transmission Output Shaft Engine MUST BE positioned correctly (as described in next step) to achieve proper engine operation and to prevent damage to drive shaft. If drive shaft is run at incorrect angle damage to universal joint bearings may result. 5. Position engine so that it is 1" to 1-5/16" (25 to 33mm) above or below starboard engine and parallel to crankshaft centerlme of starboard engine (both vertically and horizontally). Also, make sure that engine is directlv in line with tailstock housing. Move engine back-or-forward. as required, so that driveshaft splines (Figure 6) are positioned at approximately mid travel. This position will place driveshaft at a l°-3° angle to crankshaft centerline which is necessarv for proper drive shaft operation. 6. After engine has been positioned correctlv. fasten front and rear plate mounts to angle irons using fasteners that had been removed. Tighten bolts and nuts securelv. 7. Refer to "Completing Installation ". COMPLETING INSTALLATION 1. Connect hvdraulic hoses to reverse lock valve as shown in Figure 7 (some models). 2. Models w ith Engine Oil Cooler Mounted on Stringer: Connect oil hoses to the same fittings that they were removed from. 3. Models with Transmission Oil Cooler .Mounted on Stringer: Connect oil hoses to the same fittings that they were removed from. a - Reverse Lock Valve o - Plastic Hose (From Power Trim Pump) c - Gray Hose (From Transom Assembly) Figure 7. Reverse Lock Valve (Some Models) 90-95693 485 REMOVAL, INSTALLATION and ALIGNMENT - 2E-11 IMPORTANT: Check all oil levels before and after first 5 minutes of running time. Power Steering Models: a. Fluid Cooler Mounted on Engine: Reconnect fluid hoses to power .steering control valve as shown in Figure 8. b. Fluid Cooler Mounted on Stringer: Reconnect fluid hoses to cooler. IMPORTANT: Bleed power steering system as outlined in "Stern Drive Service Manual". 5. Reconnect anv grounding wire or accessories that were removed. 6. Connect shift cable. Refer to "Attaching/Adjusting Shift Cable". 7. Reconnect trim position sender wire (some models). 8. Reconnect seawater inlet hose and exhaustsystem. Tighten clamps securely. 9. Reconnect red and black Power Trim pump motor wires to engine (some models). 10. Reconnect fuel line. Check for fuel leaks. 11. Connect throttle cable. Refer to "Attaching/Adjusting Throttle Cable". 12. Connect instrument harness to engine harness. Secure with clamp and tighten securelv. 13. Connect batterv cables to batterv. ATTACHING/ADJUSTING SHIFT CABLE MODELS WITH REVERSE LOCK VALVE 1. Place remote control handle in full forward position. 2. Place transmission .n forward gear by moving shift cable lever to the right until detent ball, which is located behind transmission shift lever, is centered in rear hole in transmission shift lever. (Figure 1) 3. Place cable end guide on stud which is located in shift cable lev er. (Figure 2) 03806 03805 a - Anchor Stud b - Brass Barrel c - Cable End Guide d - Stud e - Washer and Nut Figure 2. Shift Cable Installed a - Shift Lever b - Rear Hole and Detent Ball Figure 1. Forward Gear 90-95693 485 2E-10 - REMOVAL. INSTALLATION and ALIGNMENT 4. Adjust brass barrel on shift cable so that barrel can be placed on anchor stud without disturbing shift cable lever position. (Figure 2) 5. Fasten end guide to shift cable lever stud with flat washer and nut. Tighten nut and then back nut off slightlv to allow end guide to pivot freely. (Figure 2) 6. Fasten brass barrel toanchor stud with flat washer and nut. Tighten nut securelv. (Figure 2) 7. Place remote control handle in full reverse position. 8. Loosen nut which fastens stud to shift cable lever. Move shift cable lever to the left, while sliding stud down slot in lever, until detent ball is centered in front hole in l ransmission shift lever. Tighten nut securelv. (Figure 3) 9. Check adjustment by mov ing remote control handle to full forward. Detent ball must be centered in rear hole in transmission shift lever. (Figure 1) Move control handle to full reverse position. Detent ball must be centered in front hole in transmission shift lever. (Figure 3) If transmission shift lever is not positioned correctlv and does not permit detent ball to be centered in holes, as described previously, readjust cable. 10. Move remote control handle to full reverse position. 11. Mark, which is located on valve cam lever,and large mark, located oti valve cover, must line up as shown in Figure 4. If marks do not line up as shown, loosen nuts A" and reposition cam lever. Tighten nuts securelv after adjustment. 03808 a - Slot b - Front Hole and Detent Ball Figure 3. Reverse Gear MODELS WITHOUT REVERSE LOCK VALVE 1. Place remote control shift lever in neutral position. 2. Place transmission shift lever in neutral position, indicated when poppet ball (located behind shift lever) is in center detent hole of shift lever. (Figure 5) a - Shift Lever b - Poppet Ball In Center Hole of Shift Lever Figure 5. Neutral Position 3. Adjust brass barrel on shift cable, as required, to align shift cable attaching holes with shift cable lever and shift cable anchor studs. Center the cable end plav travel when making adjustment. 4. Install shift cable and secure with flat washers and elastic- stop nuts. (Figure 6) Tighten nuts to specifications. 16476 a - Lever Stud b Washer and Nut c Cable End Guide e - Washer and Nut f - Brass Barrel g - Shift Cable Barrel Clamp Block h - Washer d Anchor Stud Figure 6. Models Without Reverse Lock Valve a - Adjustment Nuts b - Cam Lever c - Valve Cover Figure 4. Reverse Lock Valve Adjustment 04276 90-95693 485 REMOVAL, INSTALLATION and ALIGNMENT - 2E-9 5. Place remote control shift lever in full forward gear position. Check position of transmission shift lever. Transmission shift lever MUST BE positioned so that the poppet ball is in rear detent hole of shift lever. (Figure 7) a - Shift Lever b - Poppet Ball In Rear Detent Hole c - "F" On Transmission Case Figure 7. Forward Gear Position 6. Place remote contro. lever in full reverse gear position and. again, check transmission shift lever position. Poppet ball MUST BE in front detent hole of shift lever. (Figure 8) 7. If transmission shift lever is positioned correctlv in one gear (forward or reverse), but not in the other, recheck shift cable adjustment. If transmission shift lever is not positioned properly :n both gears, move shift rod stud from top hole in transmission shift lever to bottom hole (Figure 8) and recheck for proper positioning of shift lever. If proper positioning is still not obtained, remote control does not provide sufficient shift cable travel and MUST BE replaced. Remote control and shift cable MUST position transmission shift lever so that it is fully in the forward and reverse gear detent position and over the letter "F" on transmission case when propelling boat forward. TRANSMISSION SHIFT LEVER MUST BE POSITIONED PROPERLY (WITHOUT ANY MODIFICATION TO TRANSMISSION) OR TRANSMISSION FAILURE MAY OCCUR. Warner Gear Warranty is jeopardized if the shift lever poppet ball or spring is permanently removed; if the shift lever is repositioned or changed in any manner; or remote control and cable do not position shift lever correctly. a - Shift Lever b - Poppet Ball In Front Detent Hole c - "R" On Transmission Case d - Install Shift Rod Stud in This Hole. If Necessary, To Properly Position Shift Lever With Poppet Ball Figure 8. Reverse Gear Position 2E-10 - REMOVAL. INSTALLATION and ALIGNMENT 90-95693 485 ATTACHING/ADJUSTING THROTTLE CABLE 1. Place remote control in neutral gear, idle position. 2. Fasten cable end guide as shown in Figure 1, 2, or 3. 3. Grasp throttle cable brass barrel and push cable lightly toward throttle lever. Adjust barrel to align with anchor stud. Fasten barrel £.s shown in Figure 1. 2, or 3. a - Anchor Stud b - Washer and Nut (DO NOT Over-Tighten) c - Brass Barrel d - Cable End Guide e - Lever Stud a - Anchor Stud f - Washer and Nut (DO NOT Over-Tighten) b - Bushing g - Idle RPM Adjustment Screw c - Washer and Nut (DO NOT Over-Tighten) d - Brass Barrel Figure 3. MCM 475 Turbo e - Cable End Guide f - Lever Stud g - Washer and Nut (DO NOT Over-Tighten) 4. Check that throttle valves are fully open when remote Figure 1. MCM 370/400/400 Cyclone control is in full throttle position. (Figure 4) 5. Return remote control to neutral gear, idle position. Check that idle stop screw is against stop. (Figure 2, 3 or 4) 11760A a - Anchor Stud b - Washer and Nut (DO NOT Over-Tighten) c - Brass Barrel d - Cable End Guide e - Lever Stud f - Washer and Nut (DO NOT Over-Tighten) g - Idle RPM Adjustment Screw Figure 2. MCM 440/460 Cyclone a - Tang b - Carburetor Body c - Idle RPM Adjustment Screw Figure 4. Idle/Full Throttle Check (Rochester Carburetors Only) 90-95693 485 REMOVAL, INSTALLATION and ALIGNMENT - 2E-11 SECTION 2 - REMOVAL, INSTALLATION and ALIGNMENT PART I - MIE 470-228-230255- 260-330-340 INDEX Page Torque Specifications 21-1 Lubricants 21-1 Removal 2I-2 Installation 2I-3 Alignment 2I-4 Attaching/Adjusting Shift Cable 2I-6 MIE 470/228/255/330 2I-6 MIE 230/260/340 2I-7 Models Without Dual Station Mounting Single Station 2I-8 Models With Dual Station Mounting Single and Dual Station 2I-9 Attaching/Adjusting Throttle Cable 21-10 MIE 470 21-10 MIE 228/255/330 21-10 MIE 230/260/340 Without Dual Station Mounting - Single Station 21-10 MIE 230/260/340 With Dual Station Mounting - Single and Dual Station 21-11 TORQUE SPECIFICATIONS Fastener Location Lbs. Ft. (N.m) Battery Cables Securely Engine Mount Pads Securely Hose Clamps Securely Mount Locking Nut Securely (Note 2) Propeller Shaft Coupling 50 (68) Remot RemotRemot e ee Contro ControContro l ll Shif ShifShif t tt Cabl CablCabl e ee Bras BrasBras s ss Barre BarreBarre l ll Securely Cabl CablCabl e ee En EnEn d dd Guid GuidGuid e ee (Note 1) Remot RemotRemot e ee Contro ControContro l ll Throttl ThrottlThrottl e ee Cabl CablCabl e ee Bras BrasBras s ss Barre BarreBarre l ll Securely Cabl CablCabl e ee En EnEn d dd Guid GuidGuid e ee (Note 1) Trunnion Clamping Screw/Nut 50 (68) NOTES: 1. Tighten, then back nut off 1/2 turn. 2. Bend tab against adjusting nut. LUBRICANTS LUBRICANTS 92-86154A1 Quicksilver 2-4-C Multi-Lube 90-95693 485 REMOVAL, INSTALLATION and ALIGNMENT -2E-1 REMOVAL 1. Disconnect battery cables from batterv and remove instrument panel harness connector plug from engine harness receptacle. 2. Disconnect fuel line and throttle cable. 3. Disconnect shift caKe. 4. Disconnect water inlet hose and exhaust system. 5. Disconnect any ground wires or accessories that are connected to engine. MIE 230/260/310: Disconnect audio warning system tan/blue wire as shown in Figure 1 or 2. a - Water Heat Switch b - Tan/Blue Wire (Jumper Wire to Engine Oil Pressure Switch) c - Disconnect Tan/Blue Wire (From Buzzer) Figure 2. MIE 340 5. Disconnect propeller shaft coupling from transmission coupling. 6. Support engine with suitable sling thru lifting eyes on engine and remove front and rear engine mounting bolts. (Figure 3) 7. Carefully remove engine. 15015 a - Water Heat Switch b - Tan/Blue Wire (Jumper Wire to Engine Oil Pressure Switch) c - Disconnect Tan/Blue Wire (From Buzzer) Figure 1. MIE 230/260 a - Bolts b - Slot Forward Figure 3. Engine Mounts 14890A 2E-2 - REMOVAL. INSTALLATION and ALIGNMENT 90-95693 485 INSTALLATION 1. Check all 4 mounts to ensure that all mounts are: • In the center of their up-and-down adjustment. • Slot forward. (Figure 1) • Large diameter of mount trunnion extended as shown in Figure 1. • Each mount base is downward. Tighten clamping screws and nuts slightly to prevent moving in or out. Mounts MUST BE free to pivot when installing engine. a - Slot Forward b - Locking Nut c - Adjusting Nut d - Trunnion Clamping Screw and Nut Figure 1. All 4 Mounts 2. Lift engine into boat and position on engine bed so that transmission and propeller shaft couplings are visibly aligned (no gap can be seen between coupling faces when butted together). Adjust engine bed height, if necessary, to obtain proper alignment. DO NOT use mount adjustments to adjust engine position at this time. \ OTE: Engine bed MUST position engine so that a minimum of '/<" (6mm) up-and-down adjustment still exists on all 4 mounts after performing final alignment, following. This is necessary to allow for realigning engine in the future. 3. Check all 4 mounts to ensure that they are still positioned properly, then fasten mounts to engine bed with bolts. Tighten securely. 4. Disconnect overhead hoist and remove sling. 5. Connect fuel line. Check for leaks. 6. Connect seawater inlet hose. Tighten clamp securely. 7. Reconnect exhaust system. Tighten clamps securelv. 8. Align engine as outlined in "Alignment'" before completing installation. 9. After alignment is correct, connect propeller shaft coupling to transmission coupling. Torque bolts and nuts to specifications. IMPORTANT: Exhaust hoses must be connected to exhaust elbows so that they do not restrict the flow of discharge water from the elbow. (Figure 2 or 3) If hoses are connected incorrectly, discharge water from exhaust elbow will not flow around entire inside diameter of hose. This will cause a hot spot in the hose which may eventually burn thru. 10. Connect instrument harness plug to engine harness receptacle. Tighten clmap securely. 11. Connect the shift cable and throttle cable as outlined in: • "Attaching/Adjusting Shift Cable". • "Attaching/Adjusting Throttle Cable". 12. Reconnect any ground wire and accessories that may have been disconnected. MIE 230/260/340: Connect audio warning system as shown in Figure 4 or 5. 90-95693 485 REMOVAL. INSTALLATION and ALIGNMENT - 2I-3 15015 a - Water Heat Switch c - Tan/Blue Wire (From Buzzer) 15015 a - Water Heat Switch c - Tan/Blue Wire (From Buzzer) a - Water Heat Switch b - Tan/Blue Wire (Jumper Wire to Engine Oil Pressure Switch) c - Tan/Blue Wire (From Buzzer) Figure 4. MIE 230/260 Connection ALIGNMENT b - Tan/Blue Wire (Jumper Wire to Engine Oil Pressure Switch) Figure 5. MIE 340 Connection 13. Connect battery cables to battery. Tighten securely, IMPORTANT: Engine alignment MUST BE CHECKED with boat in the water, fuel tanks filled and with a normal load onboard. Engine must be aligned so that transmission and propeller shaft coupling centerlines are aligned and coupling faces are parallel within .003" (.07mm). (Figures 2 and 3) This applies to installations with solid couplings, as well as flexible couplings. Engine must be properlv aligned or vibration, noise and damage to transmission output shaft oil seal and bearings may result. 1. Check mating faces on transmission and propeller shaft couplings to make sure thev are clean and flat. 2. Center propeller shaft in shaft log as follows: (Figure 1) a. Push down and then lift shaft as far as it will move. Then place shaft in the middle of the movement. b. Move shaft to port and then to starboard as far as shaft will move. Ther. place shaft in the middle of the movement. c. Vi ith shaft in center of shaft log. align engine to shaft. a - Up b - Down c - Port d - Starboard 648-H Figure 1. Centering Shaft in Shaft Log IMPORTANT: Remote V-Drive Models: Refer to Remote V-Drive manufacturers instructions for drive shaft (between transmission and remote V-Drive) alignment. 3. Check that coupling centerlines align, by butting propeller shaft coupling against transmission coupling. (Figure 2) Shoulder on propeller shaft coupling face should engage recess on transmission coupling face with no resistance. XOTE: Some propeller shaft couplings may not have a shoulder on mating face. On these installations, use a straight edge to check centerline alignment. (Figure 3) Figure 2. Coupling Alignment 4. Check forangular misalignment, by hand noldingcoupling faces tightly together and checking for a gap between coupling faces with a .003" (.07mm) feeler gauge at 90° intervals. (Figure 3) 21-4 - REMOVAL, INSTALLATION and ALIGNMENT 90-956S3 485 Figure 3. Checking for Coupling Angular Misalignment 5. If coupling centerlines are not aligned or if coupling faces are more than .003" out-of-parallel. adjust engine mounts, as follows: a. TO ADJUST ENGINE UP OR DOWN (Figure 4): Loosen locking nut on mounts requiring adjustment. Raise or lower engine using adjusting nut. IMPORTANT: Both front mounts must be adjusted equally and both rear mounts must be adjusted equally to keep engine level from side- to-side. LOWER 14890A a - Locking Nut b - Adjusting Nut c - Clamping Screw and Nut d - Lag Screws e - Slot Figure 4. Adjusting Mounts b. TO MOVE ENGINE TO THE LEFT OR RIGHT (Figures 4 and 5): Loosen clamping screw and nut on all 4 mount brackets and move engine to the left or right, as necessary, to obtain proper alignment. If additional right or left adjustment is needed, a small amount of adjustment can be obtained with slot on front end of mounts. Loosen lag bolts which fasten mounts to engine bed and move engine to the right or left as required. Retighten lag bolts securely. IMPORTANT: Large diameter of mount trunnion MUST NOT extend over %" (20mm) from mount brackets on any of the mounts. (Figure 5) 6. After engine has been properly aligned, secure engine mounts, as shown in Figure 5. 3/4" (20mm) MA 14891A a - Torque Clamping Screw and Nut on All 4 Mount Brackets to Specifications b - Tighten Locking Nut on All 4 Mounts Securely (Until Lock- washer is Compressed) c - Bend Ore of the Tabs on Tab Washer Down onto Flat of Adjusting Nut. to Prevent Nut from Loosening during Operation Figure 5. All 4 Engine Mounts 7. Connect propeller shaft coupling to transmission coupling. Torque coupling attaching screws and nuts to specifications. 90-95693 485 REMOVAL. INSTALLATION and ALIGNMENT - 2I-5 ATTACHING/ADJUSTING SHIFT CABLE MIE 470/228/255/330 Remote control must provide a total shift cable travel (at transmission end) of at least 2W (70mm). This is necessary to position transmission shift lever fullv in the forward and reverse gear positions. Insufficient shift cable travel will cause transmission to slip and eventually fail. (Figure 1) IMPORTANT: Remote control and shift cable MUST position transmission shift lever EXACTLY as shown in Figures 2 and 3, or transmission failure may occur. DO NOT remove poppet ball or spring. a - 2-3/4" (70mm) Minimum b - Forward Gear c - Reverse Gear Figure 1. Total Shift Cable Movement a - Cable Brass Barrel (Does Move, Inner Core Wire Retracts) b - Brass Barrel MUST Move In This Direction When Remote Control is Shifted into Forward Gear Position c - Cable End Guide (Does Not Move) d - Transmission Shift Lever Figure 2. Shift Cable Movement 1. Place remote control lever in neutral gear position. 2. Place transmission shift lever in neutral. Lever is in neutral position when detent is in center hole of shift lever. (Figure 4) 3. Place cable end guide on anchor stud and thread barrel on cable in direction required to place hole in barrel in line with hole which is located in shift lever adaptor. (Figure 4) 4. Fasten barrel to shift lever adaptor with screw , washer and 21-6 - REMOVAL, INSTALLATION and ALIGNMENT nut. Tighten nut securely. 5. Fasten end guide to anchor stud with washer and nut. Tighten nut securelv. (Figure 4) 6. Move remote control lever to full forward gear position. 7. ('.heck position of transmission shift lever. (Figure 3) if detenl is nol in rear hole in shift lever, loosen nut on shift le\er adaptor stud and slide stud down slot in lever as required to place detenl in hole. (Figure 4) 8. Move remote control lever to full reverse position. Check position of transmission lever. (Figure 3) b - Shift Lever MUST BE Over This Letter When Propelling Boat FORWARD c - Shift Lever MUST BE Over This Letter When Propelling Boat IN REVERSE d - Poppet Ba I MUST BE Centered in Detent Hole for Each F-N-R Position (Forward Gear Shown) Figure 3. Shift Lever Positions a-Anchor Stud d - Shift Lever Adaptor b - Caple End e - Shift Lever c - Brass Barrel f - Slot Figure 4. Shift Cable Installation 90-956S3 485 MIE 230/260/340 Remote control must provide a total shift cable travel (at transmission end) of a* least 2 %" (70mm). This is necessary to position transmission shift lever fully in the forward and reverse gear positions. Insufficient shift cable travel will cause transmission to slip and eventually fail. (Figure 5) IMPORTANT: Remote control and shift cable MUST position transmission shift lever EXACTLY as shown in Figures 6 and 7, or transmission failure may occur. DO NOT remove poppet ball orspring. a - 2-3/4" (70mm) Minimum b - Forward Gear c - Reverse Gear Figure 5. Total Shift Cable Movement a - Transmission Shift Lever b - Shift Lever MUST BE Over This Letter When Propelling Boat FORWARD c - Shift Lever MUST BE Over This Letter When Propelling Boat IN REVERSE d - Poppet Ball MUST BE Centered in Detent Hole for Each F-N-R Position (Forward Gear Shown) e - Install Shrt Lever Stud in This Hole. If Necessary. To Center Poppet Ball in Forward and Reverse Detent Holes Figure 7. Shift Lever Positions 14920 a - Cable Brass Barrel (Does Not Move) b - Cable End Guide (Does Move. Inner Core Wire Extends) c - Cable End Guide MUST Move In This Direction When Remote Control is Shifted into Forward Gea- Position d - Transmission Shift Lever Figure 6. Shift Cable Movement 90-95693 485 REMOVAL, INSTALLATION and ALIGNMENT - 2E-11 Models without Dual Station Mounting Single Station (Figure 8) 1. Place remote control shift lever in neutral position. 2. Place transmission shift lever in neutral. 3. Adjust brass barrel on shift cable, as required, to align shift cable attaching holes with shift lever stud and shift cable bracket stud or screw hole. Center cable end play travel when making adjustment. 4. Install shift cableand secure as shown in Figure 8. Tighten nut that secures cable end guide until it bottoms out. then back off '/2-turn. Tighten nut that secures brass barrel securely. 5. Place remote control shift lever in full forward gear position. Check position of transmission shift lever. (Figure?) 6. Place remote control lever in full reverse gear position and again check shift lever position. (Figure 7) 7. If transmission shift lever is positioned correctly in one gear, but not in the other, recheck shift cable adjustment. If transmission shift lever is not positioned properly in both gears, move shift lever stud from top hole in shift lever to bottom hole ("e" in Figure 7) and recheck for proper positioning. If proper positioning is still not obtained. remote control does not provide sufficient shift cable travel and must be replaced. a - Shift Lever b - Shift Lever Stud c - Elastic Stop Nut (Thick) and Flat Washer d - Cable End Guide e - Cable Brass Barrel f - Shift Cable Bracket g - Anchor Stud (In-Line Transmission) h - Elastic Stop Nut (Thin) i - Flat Washer j - Anchor Screw (V-Drive) Figure 8. Shift Cable Installation 14919 V-DRIVE 14920 21-192- REMOVAL, INSTALLATION and ALIGNMENT 90-956S3 485 Models with Dual Station Mounting - Single and Dual Station (Figure 9 or 10) 1. Place remote control shift lever in neutral position. 2. Place transmission shift lever in neutral position. 3. Adjust brass barrel on shift cable to align holes in brass barrel and cable end guide with attaching points on transmission. Center cable end play travel when making adjustment. 4. Install shift cable, as shown. Tighten "g " until it bottoms out. then back off Vi-turn. Cable end guide must be free to pivot. Tighten "d" securely. 5. Place remote control shift lever in forward gear position and check position of transmission shift lever. Shift lever must be positioned as shown. (Figure 7) 6. Place remole control lever in reverse gear position and again check shift lever position. Lever must be positioned as shown in (c). (Figure 7) 7. If transmission shift lever is positioned properly in one gear, but not in the other, recheck shift cable adjustment. If transmission shift lever is not positioned properlv in both gears, move transmission shift lever stud from top hole in shift lever to bottom hole (' V in Figure 7) and recheck for proper positioning. If proper positioning is still not obtained, remote control does not provide sufficient shift cable travel and must be replaced. a - Cable End Guide d - Elastic Stop Nut and Washer g - Elastic Stop Nut and Washer b - Cable Brass Barrel e - Spacer c-- Anchor Stud f - Shift Lever Stud Figure 10. Shift Cable - Dual Station Installation Figure 9. Shift Cable - Single Station Installation Fig 90-95693 485 REMOVAL. INSTALLATION and ALIGNMENT - 2I-9 ATTACHING/ADJUSTING THROTTLE CABLE MIE 470 (Figure 1) 1. Place remote control in neutral gear, idle position. 2. Fasten cable end guide to throttle lever with flat washer and nut. 3. Grasp throttle cable behind brass barrel and push cable toward throttle lever. Adjust barrel to align with anchor stud. Fasten barrel to stud with flat washer and nut. 4. Check that throttle valves are fully open when remote control is in full forward position. With throttle valves fully open, turn wide open throttle stop adjusting screw clockwise until screw just touches throttle lever. Tighten set nut securely to prevent adjustment screw from turning. Return control to neutral gear, idle position, and check that idle stop screw is against stop. 13021 a - Washer and Nut (DO NOT Over-Tighten) b - Anchor Stud c - Cable End Guide d - Brass Barrel e - Throttle Lever f - W.O.T. Th-ottle Stop Figure 1. Throttle Cable Installation MIE 228/255/330 (Figures 2 and 3) MIE 230/260/340 without Dual Station Mounting - Single Station (Figures 2 and 3) 1. Place remote control lever in neutral, idle position. 2. Install throttle cable end guide on throttle lever screw. Grasp cable behind brass barrel and push LIGHTLY toward throttle lever, then adjust brass barrel to align hole with throttle cable anchor stud (and spacer) and slide barrel onto stud. 3. Secure brass barrel and cable end guide with flat washers and elastic stop nuts. Tighten cable attaching nuts securely. but do no: over-tighten, because anchor points must be free to pivot. a - Cable End Guide b - Bushing c - Washer, Nut and Screw (DO NOT Over-Tighten) d - Spacer e - Brass Barrel f - Washer and Nut (DO NOT Over-Tighten) g - Anchor Stud Figure 2. Throttle Cable Installed 4. Place remote control throttle lever in the full throttle position and check that carburetor throttle plates open fully and throttle lever contacts stop. (Figure 3) If they do not, check throttle cable anil linkages for binding. Return remote control to neutral, idle position and check thai carburetor throttle lever returns lo idle position and I hroltle plates are fullv closed. (Figure 3) a - Tang b - Carburetor Body c - Idle RPM Adjustment Screw Figure 3. Idle/Full Throttle Check 21-21 - REMOVAL, INSTALLATION and ALIGNMENT 90-956S3 485 MIE 230/260/340 with Dual Station Mounting Single and Dual Station (Figures 3 and 4) 1. Place remote control throttle lever in idle position and attach cable end guide to carburetor throttle lever as shown. 2. Grasp cable behind brass barrel and push lightlv as shown. \djust brass barrel to align hole with anchor stud, then slide barrel onto stud. 3. Tighten "c" and "h " securely, but do not over-tighten. 4. Place remote control throttle lever in the full throttle position and check that carburetor throttle plates open fullv and throttle lever contacts stop. (Figure 3) If they do not. check throttle cable and linkages for binding. Return remote control to neutral, idle position and check that carburetor throttle lever returns to idle position and throttle plates are fully closed. (Figure 3) 17045 17046 a - Cable End Guide e - Cable Brass Barrel b - Throttle Lever S:ud f - Anchor Stud c- ElasticStopNutand Washer g - Washer d - Spacer h - Elastic Step Nut Figure 4. Throttle Cable Installation 2E-10 - REMOVAL. INSTALLATION and ALIGNMENT 90-95693 11 SECTION 3 - ELECTRICAL SYSTEM PART A - STARTING SYSTEM INDEX Page Page Starter Identification 3A-1 Replacement Parts Warning 3A-1 Battery 3A-2 Size Recommendation 3A-2 Cable Size Precautions Testing Load Test Hydrometer TestStorageCharging GuideBattery Power as Affected by Temperature Slave SolenoidsTypesTesting DELCO-REMY STARTER MOTOR Torque SpecificationLubricants/SealantsSpecificationsNoticePeriodic InspectionRemovalInstallationSolenoid RemovalReplacement of ContactsInstallation Starter Motor RepairDisassemblyCleaning and InspectionComponent Tests Armature Test for Shorts 3A-2 3A-2 3A-2 3A-2 3A-3 3A-4 3A-4 3A-4 3A-5 3A-5 3A-7 3A-7 3A-7 3A-8 3A-9 3A-9 3A-9 3A-9 3A-10 3 A-10 3A-10 3A-10 3A-10 3A-10 3A-11 3A-11 3A-11 Armature Test for Ground 3A-11 Loose Connections 3A-12 Turning the Commutator 3A-12 Field Coil Test for Open Circuit 3A-12 Field Coil Test for Ground 3A-12 Reassembly 3A-12 Clearances 3A-14 Pinion Clearance 3A-14 Commutator End Frame Gap 3A-14 PRESTOLITE STARTER MOTOR Torque Specifications 3A-15 Lubricants/Sealants 3A-15 Specifications 3A-15 Notice 3A-16 Periodic Inspection 3A-16 Removal 3A-16 Installation 3A-16 Starter Motor Repair 3A-17 Disassemoly 3A-17 Cleaning and Inspection 3A-17 Component Tests 3A-17 Armature Test for Shorts 3A-17 Armature Test for Ground 3A-17 Loose Connections 3A-18 Turning the Commutator 3A-18 Field Coil Test for Open Circuit 3A-18 Field Coil Test for Ground 3A-18 Lubrication 3A-18 Reassembly 3A-18 Clearances 3A-19 Armature End Play 3A-19 Cover to Housing 3A-19 STARTER IDENTIFICATION a - Prestolite Number Figure 2. Prestolite Starter Motor a - Delco Number Figure 1. Delco-Remy Starter Motor REPLACEMENT PARTS WARNING Electrical, ignition and fuel system components on your MerCruiser are designed and manufactured to comply with U.S. Coast Guard Rules and Regulations to minimize risks of fire and explosion. Use of replacement electrical, ignition or fuel system components, which do not comply with these rules and regulations, could result in a fire or explosion hazard and should beavoided. 90-95693 485 ELECTRICAL. SYSTEM - 3C-1 BATTERY SIZE RECOMMENDATION BATTERY COLD CRANKING AMPERAGE 305 350 375 450 MCM 120 MCM 898 MCM 228 MIE 228 MIE 230 MCM 260 MIE 255 MIE 260 MCM 140 MCM 165 MCM 470 MCM 485 MCM 488 MCM 330 MCM 370 MCM 400 MCM 440 MCM 460 MCM 475 MIE 470 MIE 330 MIE 340 CABLE SIZE IMPORTANT: Terminals MUST BE soldered to cable ends to ensure good electrical contact. Use electrical grade (resin flux) solder ONLY. DO NOT use acid flux solder, as it may cause corrosion and failure. Battery electrolyte is a corrosive acid and should be handled with extreme care. If electrolyte is spilled or splashed on any part of the body, IMMEDIATELY flush the exposed area with liberal amounts of water and obtain medical aid as soon as possible. Safety glasses and rubber gloves are recommended when handling batteries. To prevent damage to the electrical system be sure to adhere to the following: • When installing battery, be sure to connect the (-) negative (grounded) battery cable to the (-) negative battery terminal and (+) positive battery cable to (+) positive battery terminal. • Never disconnect the battery cables while the engine is running. • If a charger or booster is to be used, BE SURE to connect it in parallel with existing BATTERY CABLE Cable Length Cable Gauge Up to 3-1/2 Ft. (1.1m) 3-1/2-6 Ft. (1.1-1.8m) 6-7-1/2 Ft. (1.8-2.3m) 7-1/2 - 9-1/2 Ft. (2.3-2.9m) 9-1/2 - 12 Ft. (2.9-3.7m) 12-15 Ft. (3.7-4/6m) 15- 19 Ft. (4.6-5.8m) 4 (19mm2) 2 (32mm2) 1 (40mm2) 0 (50mm2) 00 (62mm2) 000 (81mm2) 0000 (103m-n2) Both positive (+) and negative (-) cables battery (positive to positive and negative to negative). • When applying a booster charge to battery, disconnect both cables from battery (to prevent damage to voltage regulator). • Check battery condition periodically. • Make sure that battery leads are kept clean and tight. TESTING Load Test PRECAUTIONS A strong battery must be maintained. If battery shows less than 91/2 volts when under starting load, it should be recharged. Check with DC voltmeter. Hydrogen gases that escape from the battery during charging are explosive. Be sure that battery area is well ventilated and that bilge blower is in operation when charging. DO NOT smoke or allow sources of spark or open flame in area when charging battery. 3A-2 - ELECTRICAL SYSTEM 90-95693 485 hydrometer at eye level so that float is vertical and free of Hydrometer Test outer tube, then take reading at surface of liquid. When using a hydrometer, observe the following points: 5. Avoid dropping electrolyte on boat or clothing, as it is 1. Hvdrometer must be clean (inside and out) to insure an extremely corrosive. Wash off immediately with baking accurate reading. soda solution. 2. Never take hydrometer readings immediately after water has been added. 3. If hydrometer has built-in thermometer, draw liquid in several times to ensure correct temperature before taking reading. Test battery in well ventilated area as gases 4. Hold hvdrometer vertically and draw in just enough liquid given off by battery are hazardous. from battery cell so that float is free-floating. Hold Batteries tested below IS DEAD NEEDS FULLY CHARGING CHARGED It is the activity of the acid (hyd. reading) which determines the activity of that cell Fully Charged 1.280 1.260 75% Charged 1.230 1.220 50% Charged 1.180 1.170 25% Charged 1.130 1.120 Discharged 1.080 1.070 90-95693 485 ELECTRICAL. SYSTEM - 3C-3 • Set battery on wood or in carton, store in cool, dry place. STORAGE • Check every 20 days for fluid level and slow charge. • Remove batterv and clean exterior. IMPORTANT: A discharged battery can be dam • Check fluid level and fill if low. aged by freezing. • Cover terminals anc bolts with light coat of grease. CHARGING GUIDE 12 Volt Battery Recommended Rate* and Time for Fully Discharged Condition Twenty Hour Rating 5 Amperes 10 Amperes 20 Amperes 30 Amperes 40 Amperes 50 Amperes 50 Ampere-Hours 10 5 2-1/2 2 or Less Hours Hours Hours Hours Above 50 to 15 7-1/2 3-1/4 2-1/2 2 1-1/2 75 Ampere-Hours Hours Hours Hours Hours Hours Hours Above 75 to 20 10 5 3 2-1/2 2 100 Ampere-Hours Hours Hours Hours Hours Hours Hours Above 100 to 30 15 7-1/2 5 3-1/2 3 150 Ampere-Hours Hours Hours Hours Hours Hours Hours Above 150 20 10 6-1/2 5 4 Ampere-Hours Hours Hours Hours Hours Hours *Inilia! rate for constant voltage taper rate charger To avoid damage, charging rate must he reduced or temporarily halted, if : 1. Electrolyte temperature exceeds 12SC F (52° C). 2. Violent gassing or spacing of electrolyte occurs. Batte-\ is fully charged when, over a tuo hour period at a low charging rate in amperes, all cells are gassing frecl\ and no change in specific gravity occurs. For the most satisfactory charging, the lower charging rates in amperes arc recommended. Full charge specific gravity is 1.260-1.280. corrected for temperature with electrolyte level at split ring. BATTERY POWER as AFFECTED by TEMPERATURE 3A-4 - ELECTRICAL SYSTEM 90-95693 485 SLAVE SOLENOIDS TYPES There are two ("standard" or "switch") types of slave solenoids used on MerCruiser engines. MCM/MIE 470 and MCM 485 engines (with Prestolite starter motors) use a "switch type" slave solenoid as a starter solenoid. The other engines use a slave solenoid to energize the starter motor solenoid. Some model engines use the small terminal on the "switch type" solenoid for ignition by-pass during the starting of the engine. Because of this, be sure to use correct type of slave solenoid for replacement. (Figures 1 and 2) a - From Key Switch (12 Volts in Start Position) b - To Ground c - 12 Volts From Battery d - 0 Volts To Starter e - 12 Volts To Starter Figure 1. "Standard Type" Slave Solenoid 90-95693 485 ELECTRICAL SYSTEM - 3A-5 a - From Key Switch (12 Volts in Start Position) b - Mounting Bracket and Ground c - 12 Volts From Battery d - 0 Volts To Starter e - 0 Volts To Ignition Coil f - 12 Volts To Starter g - 12 Volts To Ignition Coil Figure 2. "Switch Type" Slave Solenoid 3A-6 - ELECTRICAL SYSTEM 90-95693 485 TESTING b. Connect jumper wire from positive (+) terminal on 12 volt battery to "a" terminal on solenoid. 1. Disconnect battery cables, then remove all wires from c. Connect jumper wire from negative (-) terminal of solenoid terminals. battery to "b" mounting bracket. 2. Remove solenoid. d. If meter does not move, replace solenoid. 3. Standard Type (Figure 1): e. To test ignition by-pass, move meter lead from "f " a. Connect continuity meter to large terminals. terminal to "g" terminal. If meter does not move, b. Connect jumper wire from positive (+) terminal on 12 replace solenoid. volt battery to "a" terminal on solenoid. 4. Install solenoid. c. Connect jumper wire from negative (-) terminal of 5. Reconnect wires to terminals. Tighten securely and coat battery to "b" terminal on solenoid. with Liquid \eoprene. d. If meter does not move, replace solenoid. 6. Reconnect battery cables. Tighten securely. Switch Type (Figure 2): a. Connect continuity meter to large terminals. PELCO-REMY STARTER MOTOR TORQUE SPECIFICATIONS Fastener Location Lbs. Ft. (N.m) Lbs. In. (N.m) Battery Cables Securely Starter End Cap 110 (12) Starter to Block 50 (68) LUBRICANTS/SEALANTS LUBRICANTS/SEALANTS 92-25711 Quicksilver Liquid Neoprene 92-32447 Quicksilver Perfect Seal SAE 10W Oil SAE 20W Oil 90-95693 485 ELECTRICAL SYSTEM - 3A-7 SPECIFICATIONS DELC DELCDELC O OO IDENTIFICATIO IDENTIFICATIOIDENTIFICATIO N NN NUMBE NUMBENUMBE R RR ENGIN ENGINENGIN E EE ROTATIO ROTATIOROTATIO N NN NO LOAD TEST BRUS BRUSBRUS H HH SPRIN SPRINSPRIN G GG TENSIO TENSIOTENSIO N NN OZ OZOZ . .. (GRAMS (GRAMS(GRAMS ) )) VOLTS MIN. AMPS MAX. AMPS II MAX. RPM 1108525 R.H. 10.6 45 110 3500 6700 40-70 (1133-1984) 1108742 L.H. 10.6 45 110 3500 6700 40-70 (1133-1984) 1108755 L.H. 10.6 55 110 2800 6400 56-105 (1588-2976) 1108756 L.H. 10.6 55 100 5200 11,100 40-70 (1133-1984) 1109482 L.H. 10.6 70 120 5400 10,800 56-105 (1588-2976) 1109484 R.H. 10.6 70 120 5400 10,800 56-105 (1588-2976) 1109435 L.H. 10.6 70 120 5400 -10,800 56-105 (1588-2976) 1109438 L.H. 106 70 120 5400 10,800 56-105 (1588-2976) 1109439 L.H. 10.6 60 100 5300 10,600 56-105 (1588-2976) 1109490 L.H. 10.6 60 100 5300 10,600 56-105 (1588-2976) 1998314 L.H. 10.6 70 120 5400 10,800 56-105 (1588-2976) 1998315 R.H. 10.6 70 120 5400 10.800 56-105 (1588-2976) 1998316 L.H. 10.6 70 120 5400 10,800 56-105 (1588-2976) 1998317 L.H. 10.6 70 120 5400 10,800 56-105 (1588-2976) 1998318 L.H. 1C.6 60 100 5300 10,600 56-105 (1588-2976) 1998404 L.H. 1C.6 60 100 5330 10,600 56-105 (1588-2976) 1998460 L.H. 10.6 60 100 5300 10,600 56-105 (1588-2976) PINION CLEARANCE .010-.140 (.25 -3.5mm) COMMUTATOR END FRAME GAP .025 MAX. (,6mm MAX ) L.H. = LEFT HAND ENGINE ROTATION R.H. = RIGHT HAND ENGINE ROTATION 90-95693 485 3A-8 -ELECTRICAL SYSTEM NOTICE The starter motor is designed to operate under great overload must never be used for more than 30 seconds at any one time. and produce a high horsepower for its size. It can do this only Cranking should not be repeated without a pause of at least 2 for a short time, since considerable heat accumulates and can minutes to permit the heat to escape. cause serious damage. For this reason, the cranking motor PERIODIC INSPECTION Cranking motor and solenoid are completely enclosed in the 1. Inspect terminals for corrosion and loose connections. drive housing to prevent entrance of moisture and dirt. How-2. Inspect wiring for frayed and worn insulation. ever. periodic inspection is required as follows: 3. Check mounting bolts for tightness. REMOVAL 3. Pull starter assembly away from flywheel and remove from engine. IMPORTANT: Some starter motors may have a special shim between mounting surface. DO NOT lose this shim. INSTALLATION l. Place starter assembly in position and install mounting bolts. Torque fasteners to specifications. IMPORTANT: Install special shim (if equipped) between starter motor and block. 2. Connect wires to solenoid terminals. 3. Connect red battery cable to large solenoid terminal and install boot over terminal (if equipped). 4. Connect battery cables to battery. a - Large Terminal b - Fuse (If Equipped) c - Boot (If Equipped. Place Over Terminal) d - Positive (+) Battery Cable e - Negative (-) Battery Cable Figure 1. Typical Starter Motor 1. Disconnect wires from solenoid terminals. 2. Remove starter mounting bolts. 90-95693 485 ELECTRICAL SYSTEM - 3A-9 SOLENOID REMOVAL INSTALLATION Remove starter motor as outlined. 1. Install solenoid return spring on plunger. Remove screw and washer from starter motor connector 2. Position solenoid assembly to starter motor and turn sole- strap terminal. noid to engage flange key in key way slot. Remove 2 screws which hold solenoid assembly to starter 3. Install 2 screws which hold solenoid assembly to end motor end frame. frame. 4. Twist solenoid clockwise to remove flange key from key-4 Secure starter motor connector strap terminal with screw way slot (located in starter motor), then remove solenoid and washer. assemblv. 5 Install starter motor as outlined. REPLACEMENT of CONTACTS 1. Remove nuts and washers from switch ("S") terminal and starter motor connector strap terminal. (Figure 2; 2. Remove 2 solenoid end cover retaining screws and washers and remove end cover. 3. Remove nut and washer from batterv terminal on end cover and remove batterv terminal. IMPORTANT: DO NOT cut starter motor connector strap terminal wire to remove terminal, or wire will be too short. 4. Remove motor connector strap terminal and solder new- terminal in position. 5. Remove and install new batterv terminal, washer and re01449A taining nut. 6. Install new contact ring and push rod assemblv. a - Solenoid Body f - Contact Ring & Rod c - Switch Terminal h - Contact Finger 7. Position end cover over switch and motor terminals and b - To Hoid in Coil g Battery Terminal install end cover retaining screws. Also install washersand d - Motor Connector Strap i - End Cover nuts on solenoid switch and starting motor terminals. e - To Pu i in Coil Figure 2. Exploded View of Solenoid STARTER MOTOR REPAIR DISASSEMBLY 1. Remove screw and washer which fasten motor field coil connector to solenoid terminal. 2. Remove thru bolts. 3. Remove commutator end frame, field frame assembly and armature assemblv from drive housing. 4. Remove over-runr.ing clutch from armature shaft as follows: a. Slide thrust collar off of armature shaft. b. Slide standard Vi" pipe coupling or other metal cylinder of correct size onto shaft. (Figure 3) Tap end of coupling with hammer, driving retainer toward armature. c. Remove snap ring from groove. d. Slide retainer and clutch assemblv from armature shaft. 5. Disassemble brushes and related parts from field frame as follows: a. Remove pin. which passes thru brush support and brush holders, and remove. b. Disconnect leads from brushes. a - Cylinder b - Retainer Figure 3. Driving Off Retainer 3A-10 - ELECTRICAL SYSTEM 90-95693 485 01439 CLEANING and INSPECTION IMPORTANT: DO NOT use grease dissolving solvents for cleaning electrical componentsand bushings of starter motor. Such a solvent would damage insulation and remove lubricating qualities from bushings. With starting motor completely disassembled (except for removal of field coils), component parts should be cleaned and inspected. Field coils should be removed only where defects are indicated by tests. Defective parts should be replaced or repaired. 1. Clean all starting motor parts but do not use dissolving solvents for cleaning over-running clutch, armature and field coils. Such a solvent would dissolve grease packed in clutch mechanism and damage armature and field coil insulation. 2. Test over-runningclutch action. Pinion should turn freely in over-running direction and must not slip in cranking direction. Check pinion teeth. Check spring for tension and drive collar for wear. Replace, if necessary. 3. Check that brush holders are not damaged or bent and will hold brushes against commutator. 4. Check brushes. Replace if pitted or worn to one-half their original length (5/16" (8mm) or less). 5. Check fit of armature shaft in bushing of drive housing. Shaft should fit snugly. Replace bushing, if worn, Apply SAE 20 oil to this bushing before reassembly. Avoid excessive lubrication. 6. Check fit of bushing in commutator end frame. If bushing is damaged or worn excessively, replace end frame assembly. Apply SAE 20 oil to this bushing before reassembly. Avoid excessive lubrication. 7. Inspect armature commutator. If rough or out-of-round, turn down and undercut. Inspect points (where armature conductors join commutator bars) for good, firm connection. Burned commutator bar usually is evidence of poor connection. COMPONENT TESTS Armature Test for Shorts Check armature for shorts by placing on growler and holding hack saw blade over armature core while rotating armature. (Figure 4) If saw blade vibrates, armature is shorted. After cleaning between commutator bars, recheck. If saw blade still vibrates, replace armature. a - Commutator b - Armature Core c- Shaft d - Growler Figure 5. Armature Test for Ground Field Coil 01440 a - Hacksaw Blade b - Armature Core c - Growler Figure 4. Armature Tests for Shorts Armature Test for Ground 1. With continuity meter, place one lead or armature core or shaft and other lead on commutator. 2. If meter hand moves to right, armature is grounded and must be replaced. (Figure 5) 90-95693 485 ELECTRICAL. SYSTEM - 3C-11 1. W ith continuity meter, place one lead on field connector Loose Connections If open soldered connection of armature to commutator leads is found during inspection, resolder with rosin flux. IMPORTANT: Never use acid flux on electrical connections. Turning the Commutator When inspection shows commutator roughness, clean as follows: 1. Turn down commutator in a lathe until thoroughly cleaned. 2. Recheck armature on growler for short circuits. Field Coil Test for Open Circuit 1. W ith continuity meter, place one lead on each end of field coils (insulated brusn and field connector bar). (Figure 6) 2. If meter hand does r.ot move to right, field coils are open and must be replaced. 01442 a - Field Connector Bar b - Insulated Brush Figure 6. Field Coil Test for Open Circuit Field Coil Test for Ground IMPORTANT: Be sure that positive brushes and leads do not contact field frame assembly during test, or false reading will result. bar and other lead on grounded brush. (Figure 7) 2. If meter hand move? to right, field coils are grounded and must be replaced. a - Grounded Brush b - Brush Holder c - Field Connector Bar Figure 7. Field Coil Test for Ground REASSEMBLY After all parts are thoroughlv tested and inspected and worn or damaged parts replaced, reassemble starter as follows: 1. Assemble brushes and related parts to field frame as follows: a. \ssemble brushes to brush holders. b. \ssemble insulated and grounded brush holders together with \ " spring. Position as a unit and install support pin. Push holders and sprirg to bottom of support and rotate spring to engage center of \ spring in slot of support. c. \ttach ground wire to grounded brush and field lead wire to insulated brush. 2. \ssemble over-running clutch assembly to armature shaft as follows: a. Lubricate drive end of armature shaft with SAE 10 oil. b. Slide assist spring and clutch assemblv onto armature shaft with pinion outward. c. Slide retainer onto shaft with cupped surface facing end of shaft (awav from pinion). d. Position snap ring on upper end of shaft and hold in place with block of wood. Strike wood block with hammer, thus forcing snap ring over end of shaft, (f igure 8) Slide snap ring down into groove. 3A-12 - ELECTRICAL SYSTEM 90-95693 485 a - Snap Ring b - Groove Figure 8. Forcing Snap Ring over Shaft e. Assemble thrust collar on shaft with shoulder next to snap ring. f. Position retainer and thrust collar next to snap ring. Then, using 2 pliers, grip retainer and thrust collar and squeeze until snap ring is forced into retainer. (Figure 9) a - Thrust Collar b - Retainer c - Snap Ring Figure 9. Forcing Snap Ring into Retainer 3. Place 4 or 5 drops of SAE 10 oil in drive housing bushing. Slide armature and clutch assemblv into place in drive housing while engaging shift lever with clutch. 4. Position field frame over armature and apply Liquid Neoprene between frame and solenoid case, observing caution to prevent damage to brushes. 5. Place 4 to 5 drops of SAE 10 oil in bushing in commutator end frame. Place leather brake washer on armature shaft and slide commutator end frame onto shaft. 6. Install solenoid as outlined. 7. After reassembly, a "no load" check of starting motor may be made if equipment is available. To check, connect starter motor in series with a fully-charged 12-volt battery, an ammeter capable of reading several hundred amperes and a variable resistance. 8. Also, connect a voltmeter, as illustrated, from motor terminal to motor frame. An RPM indicator is necessarv to measure armature speed. (Figure 10) Obtain specified voltage by varying resistance unit. Then read current draw and armature speed and compare these readings with specifications. a - Ammeter b - Voltmeter c - Variable Resistor d - Jumper Lead e - RPM Indicator Figure 10. No Load Test Hookup 90-95693 485 ELECTRICAL SYSTEM - 3A-13 CLEARANCES Pinion Clearance Pinion clearance must be checked after reassembly of motor to insure proper adjustment. 1. Disconnect motor field coil connector from solenoid motor terminal and insulate it carefully. 2. Connect 12-volt battery from solenoid switch terminal to solenoid frame. (Figure 11) 3. Momentarily touch a jumper lead from solenoid motor terminal to starter motor frame. This shifts pinion into cranking position where it will remain until battery is disconnected. Figure 11. Circuit for Checking Pinion Clearance 4. Push pinion back toward commutator end to eliminate slack. 5. Measure distance between pinion and pinion retainer. (Figure 12) 6. If clearance is not within specified limits, it may indicate excessive wear of solenoid linkage, shift lever yoke buttons, or improper assembly of shift lever mechanism. Replace worn or defective parts, since no provision is made for adjusting pinion clearance. a - Pinion b - Retainer c - Feeler Gauge Figure 12. Checking Pinion Clearance Commutator End Frame Gap In order to maintain the ignition-proof characteristics designed into the starter for safety, the gap between the commutator end frame and the starter field coil housing must be checked. Generally, no gap will be found. If the gap exceeds specifications, when checked with a feeler gauge, the end frame should be checked for proper seating on the field coil housing. If properly seated and still found to have excessive gap. the end frame must be replaced. a - Check End Frame Gap Here Figure 13. 3A-14 - ELECTRICAL SYSTEM 90-95693 485 PRESTOLITE STARTER MOTOR TORQUE SPECIFICATIONS Fastener Location Lbs. Ft. (N.m) Lbs. In. (N.m) Battery Cables Securely Starter Through Bolts 50 (5) Starter to Block 60 (81) LUBRICANTS/SEALANTS LUBRICANTS/SEALANTS 92-25711 Quicksilver Liquid Neoprene 92-32447 Quicksilver Perfect Seal SAE 10W Oil SAE 20W Oil SPECIFICATIONS IDENTIFICATION NUMBER MERCURY (PRESTOLITE) ENGINE ROTATION NO LOAD TEST BRUSH SPRING TENSION OZ. (GRAMS) VOLTS MIN. AMPS MAX. AMPS MIN. RPM MAX. RPM 50-72550A1 (MHA-7016) L.H. 11 N/A 70 5500 N/A 32-40 (910-1133) 50-88671A1 (MHA-7020) R.H. 11 N/A 70 5500 N/A 32-40 (910-1133) ARMATURE END PLAY .005" . 030" (.15 75mm) MAX. BEARING COVER CLEARANCE .012" (,3mm) MAX. L.H. = LEFT HAND ENGINE ROTATION R.H. = RIGHT HAND ENGINE ROTATION 90-95693 485 ELECTRICAL SYSTEM - 3A-15 NOTICE The cranking motor is designed to operate under great over-must never be used for more than 30 seconds at any one time. load and produce a high horsepower for its size. It can do this Cranking should not be repeated without a pause of at least 2 onlv for a short time, since considerable heat accumulates and minutes to permit the heat to escape. can cause serious damage. For this reason, the cranking motor PERIODIC INSPECTION Cranking motor and solenoid are completely enclosed in the 1. Inspect terminals for corrosion and loose connections. drive housing to prevent entrance of moisture and dirt. How-2. Inspect wiring for fraved and worn insulation. ever. periodic inspection is required as follows: 3. Check mounting bolts for tightness. REMOVAL 1. Disconnect battery cables from battery. 2. Disconnect starter cable at starter terminal and ground cable from starter mounting stud. (Figure 1) 3. Remove starter mounting bolts. (Figure 1) 4. Remove starter from engine. a - Starter Solenoid Front Terminal b - Rubber Boot (if Equipped) c - Positive (+) Battery Cable d - Starter Motor Support Bracket Stud e- Negative (-) Battery Cables f - Starter Terminal Figure 1. Starter Terminal INSTALLATION 1. Place starter motor in position on engine and install starter yellow cable from starter solenoid to starter terminal. (Figmounting bolts. Torque fasteners to specifications. ure 1) 2. Connect battery ground cable to starter mounting bolt and 3. Connect battery cables to battery. 13245 3A-16 - ELECTRICAL SYSTEM 90-95693 485 STARTER MOTOR REPAIR DISASSEMBLY 1. Remove 2 thru bolts and cover assembly from commutator end of starter motor. 2. Remove starter housing from armature and end frame assembly. 3. Remove 2 screws, which hold intermediate bearing assembly to end frame assembly, and remove end frame assembly. 4. Remove pin and bendix drive assembly and intermediate bearing assembly from armature shaft. IMPORTANT: DO NOT perform Steps 5, 6 and 7, unless replacement of those parts is necessary. 5. Remove 3 screws and brush plate assembly. Springs and brushes may be removed if needed. 6. Disconnect field wire from terminal stud and remove 4 screws, field assembly and pole shoes. 7. Remove nuts and remove terminal stud package. CLEANING and INSPECTION IMPORTANT: DO NOT use grease dissolving solvents for cleaning electrical components and bushings of starter motor. Such a solvent would damage insulation and remove lubricating qualities from bushings. 1. Use a brush or compressed air to clean field coils, armature, commutator, brushes and bushings. Wash all other parts in solvent and dry parts with compressed air. 2. Check armature visually for mechanical defects, such as worn or bent shaft, worn commutator, scored core laminations or unsoldered connections. 3. If commutator is rough, burned, out-of-round or has high mica, turn it down. 4. Test armature for short and ground. 5. Inspect armature shaft and bearings for scoring and excessive wear. 6. If brushes are oil soaked or worn to less than 'A" (6mm), they should be replaced. 7. Check brush spring tension during reassembly. 8. \ isually inspect field coils for burned or broken insulation. Also check fields for opens and ground. 9. Examine wear pattern on starter drive teeth. Pinion teeth must penetrate to depth greater than V2 ring gear tooth depth on flywheel This is necessary to eliminate premature ring gear and starter drive failure. 10. Replace starter drives and ring gears with milled, pitted or broken teeth or those which show evidence of inadequate engagement. a - Core b - Commutator c - Shaft d - Growler Figure 3. Armature Test for Ground 90-95693 485 COMPONENT TESTS Armature Test for Shorts Check armature for short circuits by placing armature on growler and holding hacksaw blade over core while rotating armature. (Figure 2) If saw blade vibrates, armature is shorted. After cleaning between commutator bars, recheckarmature on growler. If saw blade still vibrates, replace armature. a - Hacksaw Blade b - Armature Core c - Growler Figure 2. Armature Test for Shorts Armature Test for Ground 1. W ith continuity meter, place one lead on armature core or shaft and other lead alternately on commutator segments. 2. If meter indicates continuity, armature is grounded and must be replaced. (Figure 3) Loose Connections If open soldered connection of armature to commutator leads is found during inspection, resolder with rosin flux. IMPORTANT: Never use acid flux on electrical connections. Turning the Commutator When inspection shows commutator roughness, clean as follows: 1. Turn down commutator in a lathe until thoroughly cleaned. 2. Recheck armature on growler for short circuits. Field Coil Test for Open Circuit With continuity meter, place one lead on starter terminal and other lead to positive (insulated) brush. (Figure 4) If meter does not indicate continuity, field coils are open and must be replaced. a - Starter Terminal b - Positive Brushes Figure 4. Field Coil Test for Open Circuit Field Coil Test for Ground 1. Disconnect shunt field w ire from brush holder if holder is still installed. (Figure 5) IMPORTANT: Take care that positive brushes, brush leads and shunt field wire do not contact starter housing assembly during test, or false reading will result. 2. Connect continuity meter, with one lead to starter terminal and other lead to starter housing. (Figure 5) If meter indicates continuity, field coils are grounded and need replacement. a - Starter Terminal b - Shunt Field Wire c - Starter Housing Figure 5. Field Coil Test for Ground LUBRICATION Periodic lubrication of starting motor is not required; however, during reassembly of starter motor (especially if parts have been cleaned), bearings should be soaked in SAE 10 oil. Also, lubricate drive end of armature shaft sparingly with a film of SAE 10 oil. REASSEMBLY IMPORTANT: If brush plate assembly, field windings and terminal stud package have not been removed, start reassembly at Step 4. 1. Install terminal stud package in sequence shown in Figure 6. Check with continuity meter to be sure that stud is insulated from starter housing. 90-95693 485 3A-18 - ELECTRICAL SYSTEM 2. Place field windings and pole shoes in starter housing. Install 4 screws thru starter housing and into poles. Tighten screws securely. 3. Place brush plate assembly in position and install 3 screws and lockwashers thru starter housing and into plate assembly. Install shunt ground wire to brush plate assembly. Install brush springs. 4. Lubricate bearing surface of intermediate bearing assembly and install assembly on armature shaft. Lubricate drive end of armature shaft sparingly with a film of SAE 10 oil. Place bendix drive assembly on shaft and install roll pin. 5. Lubricate bearing (located in end frame assembly) and install armature assembly into end frame. Install 2 screws and lockwashers thru intermediate bearing assembly and into end frame. Tighten securely. 6. Position armature assembly in starter housing. 7. Check brush spring tension. Measure with scale hooked under brush spring near brush. Pull on line parallel to face of brush and take reading just as spring leaves brush. Tension must be within specifications. 8. Lubricate bearing in cover assembly and position cover on armature shaft and starter housing. Insert thru bolts and torque to specifications. a - Armature Shaft b - Check Cover Clearance Figure 7. Clearances CLEARANCES Armature End Play Check armature shaft end play. Clamp starter motor iri vise. Use dial indicator on end of armature shaft. (Figure 7) Move shaft to one end of starter housing. Zero dial indicator. Move shaft to other end of housing. Reading must fall within specifications. To correct end play, use different thickness thrust washer on armature shaft. Cover to Housing Check clearance between cover and housing assembly. (Figure 7) Clearance must not exceed specifications. If found excessive, check seating of cover onto housing. If properly seated, and excessive gap remains, replace cover. 90-95693 485 ELECTRICAL. SYSTEM - 3C-19 SECTION 3 - ELECTRICAL SYSTEM PART B - IGNITION SYSTEM INDEX IdentificationReplacement Parts WarningDELCO DISTRIBUTOR SYSTEM Torque SpecificationsTools/Lubricants/SealantsSpecifications Coil Distributor Spark Plugs Firing Order Distributor Advance Curve RepairPrecautionsDistributor Cap and RotorContact Points Replacement Condenser Coil Ignition Resistance Wire Spark Plugs High Tension Leads Distributor Repair (G.M. In-Line Engines) RemovalDisassemblyReassembly Distributor Repair (470/485/488) Removal Disassembly Reassembly Distributor Installation Engine Not Disturbed Engine Disturbed Ignition Timing MALLORY DISTRIBUTOR SYSTEM Torque Specifications Tools/Lubricants/Sealants Specifications Coil Distributor Spark Plugs Firing Order Distributor Advance Curve Page 3B-1 3B-2 3B-3 3B-3 3B-4 3B-4 3B-4 3B-4 3B-5 3B-5 3B-8 3B-8 3B-8 3B-9 3B-9 3B-11 3B-11 3B-11 3B-11 3B-12 3B-12 3B-12 3B-12 3B-13 3B-14 3B-14 3B-14 3B-15 3B-16 3B-16 3B-16 3B-17 3B-18 3B-18 3B-19 3B-19 3B-19 3B-19 3B-20 3B-20 Page Repair 3B-21 Precautions 3B-21 Distributor Cap and Rotor 3B-21 Contact Points 3B-22 Replacement 3B-22 Condenser 3B-24 Coil 3B-24 Ignition Resistance Wire 3B-24 Spark Plugs 3B-24 High Tension Leads 3B-25 Distributor Repair 3B-25 Removal 3B-25 Disassembly 3B-25 Reassembly 3B-26 Distributor Installation 3B-27 Engine Not Disturbed 3B-27 Engine Disturbed 3B-27 Ignition Timing 3B-27 THUNDERBOLT IV (HEI) SYSTEM Torque Specifications 3B-28 Tools/Lubricants/Sealants 3B-28 Specifications 3B-29 Coil 3B-29 Timing 3B-29 Spark Plugs 3B-29 Firing Order 3B-30 Distributor Advance Curve 3B-30 Repair 3B-31 Precautions 3B-31 Distributor Cap 3B-31 Rotor and Sensor Wheel 3B-32 Sensor 3B-33 Spark Plugs 3B-33 High Tension Leads 3B-34 Distributor Repair 3B-34 Removal 3B-34 Disassembly 3B-34 Reassembly 3B-34 Distributor Installation 3B-35 Engine Not Disturbed 3B-35 Engine Disturbed 3B-36 Ignition Timing 3B-36 Thunderbolt IV Testing 3B-37 IDENTIFICATION Figure 1 Delco Distributor MCM 120/140/165 18379 18383 a - MCM/MIE 470 L.H. Rotation b- MIE 470 R.H. Rotation c - Spacer on R.H. Rotation Distributor Housing Figure 2 Delco Distributor MCM/MIE 470 and MCM 485/488R IGNITION SYSTEM - 3B-1 90-95693 485 Figure 3 Mercury Marine Thunderbolt IV (HEI) Distributor Mallory Distributor MCM 898R/228R/260R/330 (B.W.) and MCM 898/228/260/330/370/400/400 Cyclone/ MIE 230/260/340 440 Cyclone/460 Cyclone/475 Turbo and MIE 228/255/330 REPLACEMENT PARTS WARNING Electrical, ignition and fuel system components on your MerCruiser are designed and manufactured to comply with U.S. Coast Guard Rules and Regulations to minimize risks of fire and explosion. Use of replacement electrical, ignition or fuel system components, which do not comply with these rules and regulations, could result in a fire or explosion hazard and should be avoided. 90-95693 1-888 3B-2- IGNITION SYSTEM DELCO DISTRIBUTOR SYSTEM TORQUE SPECIFICATIONS Fastener Location Lbs. Ft. (N.m.) Distributor Clamp 5/16-18 15 (20) Distributor Clamp 3/8-16 20 (27) Spark Plugs 14mm 15 (20) TOOLS/LUBRICANTS/SEALANTS MERCURY MARINE SPECIAL TOOLS 91-59339 Dwell Meter 91-76032 Magneto Analyzer 91-52024A1 Remote Starter Switch 91-99379 Timing Light 91-99750 Volt/Ohm Meter TOOLS OBTAINED LOCALLY Point Spring Tension Gauge SEALANTS 92-25711 Quicksilver Liquid Neoprene LUBRICANTS OBTAINED LOCALLY Distributor Cam Lubricant 90-95693 485 IGNITION SYSTEM - 3B-3 SPECIFICATIONS UNIT OF MEASUREMENT in. (mm) COIL Coil Part No. 26433 32193 Max. Operating Amps* .9 1.1 Primary Resistance* .9-1.2 Ohms 1.3-1.5 Ohms Secondary Resistance* 7,500 10,500 Ohms 9,400- 11,700 Ohms Secondary Continuity* 53-63 67-77 Resistor Wire 1.8-2 Ohms Note: * Use Magneto Analyzer DISTRIBUTOR Model 120 140 165 i 470 ! 485 488 Condenser* .18- .25 MFD. Point Dwell 28° - 34° Point Gap .022 (.5) .016 . 019 (.4 . 45) .022 (.5) Point Spring Tension 19-23 oz. (540 -650g) Timing 8° BTDC 6° BTDC 8° BTDC Note: * Use Magneto Analyzer SPARK PLUGS Model 120 140 165 470 485 488 Gap .035 (.9) Type AC MR43T AC R42TS Champion RV8C Champion RV9YC Autolite 144 Autolite 13 NGK BR6FS NGK BPR6FS 3B-4- IGNITION SYSTEM 90-95693 1-888 FIRING ORDER Figure 1 Firing Order GM 4 Cyl In-Line, Figure 2 MCM 470/485/488 and MIE 470 L.H. and 470 R.H. Firing Order for GM Rotation Engines 6 Cyl In-Line Engine DISTRIBUTOR ADVANCE CURVE IMPORTANT: Distributor advance curve charts do Example: MCM 120 and 140 advance curve chart not include the initial engine timing. Basic initial reads 29° spark advance at 2000 RPM. Add 6° timing must be added to chart for total advance BTDC initial timing for a 140 and total spark curve. advance at 2000 RPM is 35°. MCM 120/140 ENGINE RPM 693-H 90-95693 485 IGNITION SYSTEM - 3B-5 MCM 165 3B-6- IGNITION SYSTEM 90-95693 1-888 MCM/MIE 470, MCM 485/488 v / 90-95693 485 -3B-7 REPAIR PRECAUTIONS When performing the following procedure, be sure to observe the following. • Be sure that engine compartment is well ventilated and that no gasoline vapors are present, to avoid the possibility of fire. • Be sure to keep hands, feet, and clothing clear of engine moving parts. • Do not touch or disconnect any ignition system parts while engine is running. • Do not reverse battery cable connections. System is negative (-) ground. • Do not disconnect battery cables while engine is running. 18385 DISTRIBUTOR CAP and ROTOR a - Alignment Notch Location Figure 1 1. Loosen distributor cap retaining screws. 4 Cylinder 2. Remove distributor cap. Distributor Cap Wiring L.H. and R.H. Rotation IMPORTANT: If high tension leads are removed from cap refer to Figure 1 or 2. 3. Clean cap with warm soap and water and blow off with compressed air. 4. Check cap contacts for excessive burning or corrosion. Check center contact for deterioration. IMPORTANT: Distributor caps (for marine use) should have brass contacts, aluminum contacts should not be used. 5. Check cap for cracks or carbon tracks using Magneto Analyzer. 6. Remove rotor. 7. Check for burned or corroded center contact. 8. Check rotor for cracks and carbon tracks using Magneto Analyzer. 9. Install rotor on shaft. Make sure to line up rotor with keyway on distributor shaft. Be sure rotor is completely- seated on distributor shaft. 10. Place cap on distributor. Make sure notch on cap lines up 18386 with notch in distributor and cap is firmly seated. a - Alignment Notch Location 11. Tighten retaining screws securely. Figure 2 12. Install spark plug wires (if removed) as shown in Figure 1 6 Cylinder or 2. Distributor Cap Wiring 3B-8- IGNITION SYSTEM 90-95693 1-888 CONTACT POINTS 1. Examine contact points for dirt, wear, pitting and misalignment. Dirty points should be cleaned. Normal point condition is an overall grey color on contact surface. 2. Check for point resistance. A voltage drop of less than .125 volts across points should exist. Make this check with a sensitive volt meter or point resistance meter. Abnormal Point Wear 1. Points, which havebeen operated fora period of time, have a rough surface, but this may not mean that points are worn out. 2. If points burn or pit. however, they soon become unsatisfactory for further operation. Not onlv must they be replaced, but ignition system and engine must be checked to determine cause and elimination of trouble. Unless condition is corrected, new points will provide no better service than old points. Cleaning of Points 1. Dirt v contact points should be dressed with a few strokes of a clean, fine-cut contact file. File should not be used on other metals and should not be allowed to become greasy or dirty. IMPORTANT: Never use emery cloth to clean contact points. 2. Contact surfaces, after considerable use. may not appear bright and smooth, but this is not necessarily an indication that they are not functioning satisfactorily. Do not attempt to remove all roughness nor dress point surfaces down smooth. Merely remove scale or dirt. 3. Badly burned or pitted contact points should be replaced and cause of trouble determined and corrected. Burning of Points 1. Contact point burning results from high voltage, presence of oil or other foreign material, defective condenser or improper point adjustment. 2. High voltage causes excessively high current flow- thru contact points which burns them rapidly. High voltage can result from improperly adjusted or inoperative voltage regulator. 3. Oil or crankcase vapors, which work up into distributor and deposit on point surfaces, cause them to burn rapidly. 4. If contact point opening is too small (cam angle too large), points will be closed too long. Average current flow thru points will be too high, so points will burn rapidly and arcing will occur between points. 5. High series resistance in condenser circuit will prevent normal condenser action, so contact points will burn rapidly. This resistance may be caused by a loose condenser mounting or lead connection, or by poor connections inside condenser. Pitting of Points 1. Contact point pitting results from an out-of-balance condition in ignition system which causes transfer of material from one point to other so that a tip builds up on one point while a pit forms in other. (Figure 3) 2. If points are pitted, condenser should be checked for proper capacity. Replacement 1. Remove primary and condenser lead wires from contact point terminal. 2. Remove contact set attaching screw and lift contact point set from breaker plate. 3. Clean oil smudge and dirt from breaker plate. IMPORTANT: Carefully wipe protective film from point set prior to installation. 4. Place a small amount of Distributor Cam Lubricant on distributor cam. 5. Place new contact point assembly in position on breaker plate and install attaching screw. 6. Check points for porper alignment. If points do not align properly, replace with another set of points. (Figure 4) Figure 4 90-95693 485 IGNITION SYSTEM - 3B-9 7. Connect primarv and condenser lead wires to terminal on contact point set. 8. Check point spring tension (Figure 5). Contact point spring tension must fall within specified limits. Weak tension will cause chatter which results in arcing and burning of points and an ignition miss at high speed, while excessive tension will cause undue wear of contact points, cam and rubbing block. Contact point tension should be checked with a spring gauge. Scale should be hooked to breaker lever and pull exerted at 90° to breaker lever. Reading should be taken just as points separate. Tension can be adjusted by bending breaker lever spring. If tension is excessive, it can be decreased by pinching spring carefully. To increase tension, remove lever from distributor so that spring can be bent away from lever. Avoid excessive spring distortion. 18374 a - Movable Contact b - Spring Tension Gauge Figure 5 IMPORTANT: Point gap or (dwell) can be adjusted by 2 methods. It is preferred that points be adjusted with a feeler gauge, then checked with a dwell meter. Points, however, also can be adjusted, as well as checked, with a dwell meter: After points have been set, dwell should be checked with engine running. Point Adjustment With Feeler Gauges 1. Rotate distributor until rubbing block rests on peak of cam lobe, which will provide maximum breaker point opening. 2. Insert correct feeler gauge between breaker points. 3. Loosen lock screw and adjust points to specifications (Figure 6). a - Lock Screw b - Adjustment Slot Figure 6 Dwell Adjustment 1. Remove distributor cap and rotor. 2. Connect positive (+) dwell meter lead to negative (-) side of coil. Connect negative (-) meter lead lo g-ound. 3. Loosen point lock screw slightly. While cranking engine with starter, adjust dwell with a screwdriver (F igure 6) to obtain reading on dwell meter, as specified in "Specifications", and tighten lock screw. (Dwell reading will be unsteady using this method.) IMPORTANT: Cam angle increases as point opening is decreased and vice versa. (Figure 7) a - Cam b - Direction ot Rotation c - Breaker =oints Figure 7. Cam Angie d - Points Open e - Points Close f - Cam Angle or Dwell 3B-10- IGNITION SYSTEM 90-95693 1-888 5. Install rotor and distributor cap and recheck dwell with engine running. IMPORTANT: Dwell should be checked between idle and 1750 RPM. Any dwell reading variations of more than 3° between idle and 1750 RPM would indicate wear in the distributor. Cam angle readings, taken at speeds above 1750 engine RPM, may prove unreliable on some dwell meters. CONDENSER 1. Use Magneto Analyzer for test. 2. Test condenser for the following: a. Condenser capacity test. b. Condenser leakage and short test. c. Condenser series resistance test. 3. Replace condenser if test results are not within specifications. COIL 1. Use Magneto Analyzer for test. 2. Check coil for the following: a. Coil power test. b. Coil surface insulation test. c. Coil continuity test. d. Primary resistance test. e. Secondary resistance. 3. Replace coil if test results are not within specifications. IGNITION RESISTANCE WIRE Engine with Electric Choke 1. Disconnect wire from positive (+) side of coil. 2. I nplug quick disconnect (with 2 wires) from electric choke heater element. 3. Connect ohmmeter leads to ends of disconnected wires. Replace resistor wire if reading is not within specifications. 4. Reconnect wires to coil and choke. 5. For instructions on replacing resistor wire refer to "Section 3. Part E". Engine without Electric Choke 1. Disconnect wire from positive (+) side of coil. 2. 1 nplug instrumentation harness from engine harness. 3. Connect one ohmmeter lead to wire removed from coil. Connect other ohmmeter lead to No. 5 pin hole in engine harness. (Figure 8) Replace resistor wire if reading is not within specifications. 4. Reconnect wire to coil. Plug instrumentation harness onto engine harness and tighten retaining clamp securely. 5. For instructions on replacing resistor wire refer to "Section 3. Part E". SPARK PLUGS 1. Inspect each plug individually for badly worn electrodes, glazed, broken or blistered porcelain and replace where necessary. 2. Inspect each spark plug for make and heat range. All plugs must be the same make and number or heat range. Refer to "Specifications" for spark plug numbers IMPORTANT: Never bend the center electrode to adjust gap. Always adjust by bending ground or side electrode. 3. Adjust spark plug gaps with a round feeler gauge. (Figure 9) Refer to "Specifications" for proper spark plug gap. a - Porcelain Insulator b - Insulator Cracks Often Occur at this Point c - Shell d - Proper Gap e - Side Electrode (Bend to Adjust Gap) f - Center Electrode (File Flat When Adjusting Gap - Do Not Bend) Figure 9. Spark Plug Detail 90-95693 485 IGNITION SYSTEM - 3B-11 4. Clean spark plug seating area. DO NOT use gaskets on taper seat plugs. Install spark plugs and torque to specifications. Where used, gasket must be fully compressed to complete heat transfer and provide a gas-tight seal in cvlinder. For this reason, as well as necessity of maintaining correct plug gap. correct torque is very important during installation. IMPORTANT: Tapered seat spark plugs are not inter-changeable with nontapered (with gasket) spark plugs. HIGH TENSION LEADS 1. Inspect high tension leads for damage. 2. Check high tension leads for continuity. 3. Replace any leads that are cracked, cut. o- have damaged spark plug boots. 4. Replace anv leads that do not show continuity from end to end. 5. Reinstall high tension leads in proper order. IMPORTANT: Proper positioning in high tension lead supports is important to prevent cross firing. DISTRIBUTOR REPAIR (G.M. In-Line Engines) REMOVAL 1. Disconnect distributor primarv lead from coil terminal. 2. Remove distributor cap and rotor. IMPORTANT: If necessary to remove leads from distributor cap, mark position on cap towerfor lead to No. 1 cylinder. This will aid in reinstallation of leads in cap. 3. Scratch a realignment mark on distributor in line with rotor notch (located on distributor shaft). (Figure I) 4. Mark distributor housing in relation to engine block for ease in installation. 5. Remove distributor hold-down bolt and clamp and remove distributor from engine. Note position ofassembly relative to engine for correct reinstallation. IMPORTANT: Avoid rotating engine with distributor removed, as ignition timing will be upset. DISASSEMBLY IMPORTANT: It is not necessary to disassemble distributor any further than required to complete repairs. 1. Remove condenser and breaker points from breaker plate. (Figure I) Test condenser and check breaker points. 2. Remove breaker plate from distributor housing. (Figure I) Excessive oil on breaker plate assemblv would indicate a bad oil seal in distributor housing. IMPORTANT: Main shaft bushings and oil seal in housing are not serviced separately. Housing, bushings and oil seal are serviced as complete assembly. 3. Remove roll pin retaining driven gear to main shall and slide gear from shaft. 4. Check for side plate between main shaft and bushings in distributor housing. Maximum side plav allowed i- .002" (.05mm). 5. Remove main shaft from housing and inspect for worn cam lobes. Chec.< shaf t for being bent bv placing in v-hlocks and checking run out with a dial indicator. Maximum run out allowed is .002" (.05mm). 6. Remove weight cover, check weights and weight >lop lor wear. Check weights for free movement on pin-. I Figure2) a - Rotor Alignment Notch b - Breaker Plate c - Breaker Point Attaching Screw d - Alignment Mark e - Quick Disconnect Terminal f - Lubrication Wick Figure 1. Breaker Plate and Attaching Parts 18376 3B-12- IGNITION SYSTEM 90-95693 1-888 6. Install roll pin through gear and main shaft. 7. Install breaker plate on distributor housing. (Figure 1) 8. Install condenser and breaker points on breaker plate. (Figure 1) 9. Install distributor as outlined in "Distributor Installation". (see Index). 18610 a - Weight Cover b - Weight Springs c - Weights d-Weight Stop Figure 2. Advance Weights and Components REASSEMBLY 1. Install weights and springs on pivot pins. (Figure 2) 2. Install weight cover. (Figure 2) 3. Lubricate main shaft with engine oil and install iri distribua - Rotor Contact tor housing. b - Gear Alignment Mark 4. Install thrust washers (if applicable) and install driven gear on main shaft. Figure 3. Gear Installation 5. Line up mark on driven gear with rotor notch on main shaft. (Figure 3) 90-95693 485 IGNITION SYSTEM - 3B-13 DISTRIBUTOR REPAIR (470-485-488) REMOVAL DISASSEMBLY 1. Disconnect distributer primary lead from coil terminal. 2. Remove distributor cap and rotor as outlined. IMPORTANT: If necessary to remove leads from distributor cap, mark position on cap tower for lead to No. 1 cylinder. This will aid in reinstallation of leads in cap. 3. Scratch a realignment mark on distributor in line vvith rotor notch (located on distributor shaft). (Figure 1) 4. Mark distributor housing in relation to engine block for ease of installation. 5. Remove distributor hold-down bolt and clamp and remove distributor from engine. Note position of assembly relative to engine for correct reinstallation. IMPORTANT: Avoid rotating engine with distributor removed, as ignition timing will be upset. 18376 a - Rotor Alignment Notch b - Breaker Plate c - Breaker Point Attaching Screw d - Alignment Mark e - Quick Disconnect Terminal f - Lubrication Wick Figure 1. Breaker Plate and Attaching Parts IMPORTANT: It is not necessary to disassemble distributor any further than required to complete repairs. 1. Remove condenser and breaker points from breaker plate (Figure 1). Test condenser and check breaker points as previously outlined. 2. Remove breaker plate from distributor housing (Figure 1). Excessive oil on breaker plate assemblv would indicate a bad oil seal in distributor housing. IMPORTANT: Main shaft bushings and oil seal in distributor housing are not serviced separately, housing, bushings, and oil seal are serviced as a complete assembly. On right hand rotation distributors used on the MIE 470 R.H. rotation engine, the distributor housing is not available separately. You must purchase a new distributor assembly. 3. Remove roil pin retaining driven gear to main shaft (on R.H. rotation distributor vou must also remove lock ring as shown in Figure 2) and slide driven gear and driven shaft from main shaft. Remove thrust washers from main shaft. a-Lock Ring c - R.H. Rotation Gear b - Bent Lock Ring Pliers d - R.H. Rotation Distributor Housing Figure 2. R.H. Rotation Only Gear Removal 3B-14- IGNITION SYSTEM 90-95693 1-888 4. Slide driven gear from driven shaft, being careful not to lose spring on top of driven shaft. 5. (".heck for side play between main shaft and bushings in distributor housing, maximum side play allowed is .002" (,05mm). 6. Remove main shaft from housing and inspect for worn cam lobes, check shaft for being bent by placing in V-blocks and checking run out with a dial indicator. Maximum run out allowed is .002" (.05mm). 7. Remove weight cover, check weights and weight stop for wear. Check weights for free movement on pins. (Figure 3) 18610 a - Weight Cover b - Weight Springs c - Weights d - Weight Stop Figure 3 REASSEMBLY 1. Install weights and springs on pivot pins (Figure 2). 2. Install weight cover (Figure 3). 3. Lubricate main shaft with engine oil and install in distributor housing. 4. Install spring on drive shaft and install drive gear onto driven shaft. 5. Install thrust washers onto main shaft. 6. Install drive gear onto main shaft using one of the following 3 methods. I sed Gear: Line up holes in gear with hole in main shaft and install roll pin through gear and main shaft. (Also install lock ring on R.H. rotation distributor). New Gear L.H. Rotation Distributor: Hold a light downward pressure on distributor shaft. Install distributor gear onto distributor shaft. Insert a .030" feeler gauge between distributor housing washers and distributor gear. Position distributor shaft and new gear so you will drill the new hole 90° from the old hole in the distributor shaft. Place shaft and new gear on \ -blocks and drill through gear and shaft. Install roll pin through gear and main shaft. (Figure 4) IMPORTANT: The hole should be drilled with a 5/32" carbide tipped drill. In most cases it is recommended to have a machine shop complete this operation. New Gear R.H. Rotation Distributor: Install distributor gear onto distributor shaft. Install lock ring in distributor housing. (Figure2) Position distributor shaft anc new gear so vou will drill the new hole 90° from the old hole in the distributor shaft. Place shaft and new gear on \ -blocks and drill through gear and shaft (Figure 4). Install roll pin through gear and main shaft. IMPORTANT: the hole should be drilled with a 5/32" carbide tipped drill. In most cases it is recommended to have a machine shop complete this operation. a - .030" (,75mm) Feeler Gauge - L.H. Rotation Engines Only b - Drill Press c - 5/32" Carbide Tipped Drill d - V-Block Figure 4. Drilling Gear and Shaft 90-95693 485 IGNITION SYSTEM - 3B-15 7. Install breaker plate on distributor housing. (Figure 1) 8. Install condenser and breaker points on breaker plate. (Figure 1) 9. Install distributor as outlined in "Distributor Installation" (see Index). 18369 DISTRIBUTOR IMPORTANT: On 470, 485, and 488 models oil pump alignment should be checked, refer to Section 6, Part B for correct procedure. ENGINE NOT DISTURBED 1. Install new gasket on distributor housing. 2. Turn rotor approximately '/s-turn in a counterclockwise direction past mark previously scratched on distributor housing. 3. Work distributor down into position in engine block with distributor postioned as noted during removal. IMPORTANT: It may be necessary to move rotor slightly to start gear into mesh with camshaft gear, but rotor should line up with the mark when distributor is down in place. Distributor shaft must enter oil pump shaft for complete installation. 4. Replace and tighten distributor hold-down bolt and clamp. Connect primary lead to coil. Also install spark plug and coil secondary w ires, if removed. IMPORTANT: Wires must be installed in supports, to prevent cross-firing. Refer to "Specification", for firing order. 5. Set point gap and dwell. 6. Install rotor and cap. 7. Time ignition as oullined under "Ignition Timing". a - MCM 470-4&5-488-MIE 470 L.H. Rotation Distributor Gear b - MIE 470 R.H. Rotation Gear Figure 5 INSTALLATION ENGINE DISTURBED 1. Locate No. 1 piston in firing position by either of 2 methods described below. a. Remov e No. 1 spark plug and. with finger on plug hole, crank engine until compression is felt in No. 1 cylinder. Continue cranking until pointer lines up with timing mark on crankshaft pulley or . . . b. Remove rocker cover and crank engine until No.l intake valve closes, continuing to crank slowly until pointer lines up with timing mark on crankshaft pulley. 2. Position distributor to opening in block in normal installed attitude. 3. Position rotor to point toward front of engine (with distributor housing held in installed attitude), then turn rotor counterclockwise approximately '/s-turn more toward left and push distributor down to engage camshaft. It mav be necessarv to rotate rotor slightly until camshaft engagement is felt. 4. While pressing down firmly on distributor housing, engage starter a few times to make sure oil pump shaft is engaged. Install hold-down damp and bolt and snug up bolt. 5. Turn distributor body slightly until points just open and lighten distributor clamp bolt. 6. Place distributor cap in position and check that rotor lines up with terminal for No. 1 spark plug. 7. Install cap. distributor primary lead to coil. Check all high tension wire connections and connect spark plug wires, if they have been removed. Wires must be installed in their proper location in supports to prevent cross-firing. Refer to Specifications for firing order. 8. Set point gap and dwell. 9. Time ignition as outlined under Ignition Timing . 90-95693 1-888 3B-16- IGNITION SYSTEM IGNITION TIMING IMPORTANT: Dwell must be set to specification before adjusting timing. 1. Connect timing; light to No. 1 spark plug. Connect power supplv leads on light to batterv (12 volts). Refer to "Specifications"' for cylinder numbering and location. 2. Connect tachometer to engine. 3. Start engine and run at normal idle speed. 4. Aim timing light at timing marks as shown in Figures 1 or 2. 5. Adjust timing bv loosening distributor clamp and rotating distributor body as required until timing mark on balancer or pulley lines up w ith mark on tab specified in "Specifications". Tighten clamp and recheck location of timing mark. 6. Stop engine and remove timing light. IMPORTANT: GM engine timing marks (on tab) are in 2° increments. Timing must be set on the "A" (Advance) side of "O" (Top Dead Center) IMPORTANT: 470-485-488 timing marks (on tab) are in 1° increments. MCM and MIE L.H. engines will have the 10° mark to the left of "O". MIE 470 R.H. rotation engines will have the 10° mark to the right of "O" a - Timing Mark b - Degree Marks Figure 2. Timing Marks on 470-485-488 a - Timing Mark b - Degree Marks Figure 1. Timing Marks on GM 4 and 6-Cylinder Engines 90-95693 485 IGNITION SYSTEM - 3B-17 MALLORY DISTRIBUTOR SYSTEM TORQUE SPECIFICATIONS Fastener Location Lbs. Ft. (N.m) Distributor Clamp 3/8-16 20 (27) Spark Plugs (14mm) 15 (20) TOOLS/LUBRICANTS/SEALANTS TOOLS 91-59339 Dwell Meter 91-76032 Magneto Analyzer 91-52024A1 Remote Starter Switch 91-99379 Timing Light 91-99750 Volt/Ohm Meter TOOLS OBTAINED LOCALLY Spring Tension Gauge SEALANTS 92-25711 Quicksilver Liquid Neoprene LUBRICANT OBTAINED LOCALLY Distributor Cam Lubricant 3B-18- IGNITION SYSTEM 90-95693 1-888 SPECIFICATIONS UNIT OF MEASUREMENT in. (mm) COIL Coil Part No. 26433 32193 Max. Operating Amps * .9 1.1 Primary Resistance * .9-1.2 ohms 1.1 -1.5 ohms Secondary Resistance * 7,500 10.500 ohms 9,500 15,000 ohms Secondary Continuity * 53-63 60-70 Resistor Wire * 1.8-2 ohms Note: * Use Magneto Analyzer DISTRIBUTOR MODEL MCM 898 MCM/MIE 228 MIE 255 MCM/MIE 260 MCM/MIE 330 MIE 340 MCM 370/400 400 Cyclone 440/460 Cyclone 475 Turbo Condenser* .26 . 30 MFD. Point Dwell 26° -31° 28° -31° Point Gap .016 . 019 (.4 . 45) Timing 8° BTDC 10° BTDC 15° BTDC 16° BTDC Point Spring Tension 25 - 30 oz. (709-850g) Note: * Use Magneto Analyzer SPARK PLUGS MODEL MCM 898 MCM/MIE 228 MIE 255 MCM/MIE MCM/MIE 260 330 MIE 340 MCM 370/400 400/440 Cyclone 460 Cyclone 475 Turbo Plug Gap .035 (.9) Plug Type AC MR43T/ Champion RV8C Autolite 144/ NGK-BR6FS ACMR41T Champion V-4C Note 1: Use magneto analyzer IGNITION SYSTEM - 3B-19 90-95693 485 FIRING ORDER FIRING ORDER 1-8-4-3-6-5-7-2 Figure 1. MCM 898/228/260/330/370/ 400/400 Cyclone/440 Cyclone/ 460 Cyclone/475 Turbo/ MIE 228/255/330/L.H. (Standard) Rotation DISTRIBUTOR ADVANCE CURVE EXAMPLE: A 898 on the following chart reads 20° IMPORTANT: Distributor advance curve charts do spark advance at 2900 R.P.M. Add 8° BTDC initial not include the initial engine timing. Initial engine timing for an 898 and total spark advance would be timing must be added to chart for total advance 28° at 2900 R.P.M. curve. MCM 898/228/260/330 MIE 228/255/330 FIRING ORDER 1-2-7-5-6-3-4-8 Figure 2. MIE 228/255/330 R.H. (Opposite) Rotation 90-95693 1-888 3B-20 - IGNITION SYSTEM TOTAL SPARK ADVANCE FOR HIGH PERFORMANCE ENGINES IMPORTANT: This chart shows total spark advance including the initial timing of the engine. Model Max. Spark Advance Engine R.P.M. 370/400 34° 3500 400 Cyclone 36° 3500 440 Cyclone 36° 3500 460 Cyclone 36° 3500 475 Turbo 28° 3500 REPAIR IMPORTANT: Distributor caps (for marine use) should have brass contacts, aluminum contacts should not be used. PRECAUTIONS 5. Check cap for cracks or carbon tracks using Magneto Analyzer. When Performing the following procedure, be sure to observe the following. • Be sure that engine compartment is well ventilated and that no gasoline vapors are present, to avoid the possibiltiy of fire. • Be sure to keep hands, feet, and clothing clear of engine moving parts. • Do not touch or disconnect any ignition system parts while engine is running. • Do not reverse battery cable connections. System is negative (-) ground. • Do not disconnect battery cables while engine is running. DISTRIBUTOR CAP AND ROTOR 1. Loosen distributor cap clamp retaining screws. 2. Remove distributor cap. 6. Lift rotor up. off of distributor shaft. 7. Check for burned or corroded center contact. 8. Check rotor for cracks and carbon tracks using Magneto Analyzer. 9. Install rotor on shaft. Make sure to line up rotor with kevwav on distributor shaft. Be sure rotor is completely seated on distributor shaft. 10. Place cap on distributor. Make sure notch on cap lines up with notch in distributor and cap is firmly seated. 11. Tighten clamp retaining screws. 12. Install spark plug wires (if removed) as shown in Figure 1 or 2. IMPORTANT: If high tension leads are removed from cap refer to Figure 1 or 2. 3. Clean cap with warm soap and water and blow off with compressed air. 4. Check cap contacts for excessive burning or corrosion. Check center contact for deterioration. a - Alignment Notch Figure 1. L.H. Rotation 90-95693 485 IGNITION SYSTEM - 3B-21 18384 a - Alignment Notch Figure 2. R.H. Rotation CONTACT POINTS 1. Examine contact points for dirt, wear, pitting and misalignment. Diriv points should be cleaned. Normal point condition is an overall grey color on contact surface. 2. Check for point resistance. A voltage drop of less than .125 volts across points should exist. Make this check with a sensitive volt meter of point resistance meter. Abnormal Point Wear 1. Points, which have been operated for a period of time, have a rough surface, bui this mav not mean that points are worn out. 2. If points burn or pit. however, they soon become unsatisfactory for further operation. Not only must they be replaced, but ignition system and engine must be checked to determine cause and elimination of trouble. Unless condition is corrected, new points will provide no better service than old points. Cleaning of Points 1. Dirty contact points should be dressed with a few strokes of a clean, fine-cut contact file. File should not be used on other metals and should not be allowed to become greasy or dirty. IMPORTANT: Never use emery cloth to clean contact points. 2. Contact surfaces, after considerable use, may not appear bright and smooth, but this is not necessarily an indication that they are not functioning satisfactorily. Do not attempt to remove all roughness nor dress point surfaces down smooth. Merely remove scale or dirt. 3. Badlv burned or pitted contact points should be replaced and cause of trouble determined and corrected. Burning of Points 1. Contact point burning results from high voltage, presence of oil or other foreign material, defective condenser or improper point adjustment. 2. High voltage causes excessively high current flow thru contact points which burns them rapidly. High voltage can result from improperly adjusted or inoperative voltage regulator. 3. Oil or crankcase vapors, which work up into distributor and deposit on point surfaces, cause them to burn rapidly. 4. If contact point opening is too small (cam angle too large), points will be closed too long. Average current flow thru points will be too high, so points will burn rapidly and arcing will occur between points. Pitting of Points 1. Contact point pitting results from an out-of-balance condition in ignition system which causes transfer of material from one point to other so that a tip builds up on one point while a pit forms in other. (Figure 3) Figure 3. Material Transfer 2. If points are pitted, condenser should be checked for proper capacity. Replacement 1. Remove primary lead from primary terminal on distributor. Remove primary terminal screw and nut from distributor. (Use care not to lose the 2 insulator bushings in distributor housing). Remove condenser lead and point lead from primary terminal screw. 2. Remove contact set attaching screw and lift contact point set from breaker plate. 3. Clean oil smudge and dirt from breaker plate. 3B-22- IGNITION SYSTEM 90-95693 1-888 IMPORTANT: Carefully wipe protective film from point set prior to installation. 4. Place a small amount of Distributor Cam Lubricant on distribor cam. 5. Place a new contact point assembly in position on breaker plate and install attaching screw. 6. Place primary terminal screw through condenser lead and point lead. Install primary screws through 2 insulator bushings in distributor housing. Install primary terminal lock nut. primary lead, and primary lead retaining nut to primary terminal screw 7. Check points for proper alignment. If points do not align properly, replace with another set of points. (Figure 4) Figure 4 8. Check point spring tension (Figure 5). Contact point spring tension must fall within specified limits. Weak tension will cause chatter which results in arcing and burning of points and an ignition miss at high speed, while excessive tension will cause undue wear of contact points, cam and rubbing block. Contact point tension should be checked with a spring gauge. Scale should be hooked to breaker lever and pull exerted at 90° to breaker lever. Reading should be taken just as points separate. Tension can be adjusted by- bending breaker lever spring. If tension is excessive, it can be decreased by pinching spring carefully. To increase tension remove lever from distributor so that spring can be bent awav from lever. Avoid excessive spring distortion. 18373 Point Adjustment with Feeler Gauge IMPORTANT: Point gap (dwell) can be adjusted by 2 methods. It is preferred that points be adjusted with a feeler gauge, then checked with a dwell meter. Points, however, also can be adjusted, as well as checked, with a dwell meter: After points have been set, dwell should be checked with engine running. 1. Rotate distributor until rubbing block rests on peak of cam lobe, w h:ch will provide maximum breaker point opening. 2. Insert correct feeler gauge between breaker points. 3. Loosen lockscrew and adjust points to specifications (Figure 6). ] a - Adjustment Screw b - Locking Screw Figure 6. Point Adjustment Dwell Adjustment 1. Remove distributor cap and rotor. 2. Connect positive (+) dwell meter lead to negative (-) side of coil. Connect negative (-) meter lead to around. 3. Loosen point lock screw slightly. 4. W hile cranking engine with starter, adjust dwell with a screwdriver (Figure 6) to obtain reading on dwell meter, as specified in "Specifications', and tighten lockscrew. (Dwell reading will be unsteady using th.s method.) IMPORTANT: Cam angle increases as point opening is decreased and vice versa. (Figure 7) a - Movable Contact b - Spring Tension Gauge Figure 5. Checking Spring Tension IGNITION SYSTEM - 3B-23 90-95693 485 a - Cam b - Direction of Rotation c - Ereaker Points d - Points Open e - Points Close f - Cam Angle or Dwell Figure 7. Cam Angle 5. Install rotor and distributor cap and recheck dwell with engine running. IMPORTANT: Dwell should be checked between idle and 1750 RPM. Any dwell reading variations of more that 3C between idle and 1750 RPM would indicate wear in the distributor. Cam angle readings, taken at speeds above 1750 engine RPM. mav prove unreliable on some dwell meters. CONDENSER 1. I se Magneto Analyzer for test. 2. Test condenser for the following: a. Condenser capacity test. b. Condenser leakage and short test. c. Condenser series resistance test. 3. Replace condenser il lest results are not within specifications. COIL 1. I se Magneto Analyzer (or test. 2. Cheek coil for the following: a. Coil power lesi l>. Coil surface insulation tesl c. Coil continuity tesl d. Primary resistance test c. Secondary resistance lest 3. Replace coil if test results are not within specifications. IGNITION RESISTANCE WIRE Engine with Electric Choke 1. Disconnect wire from positive (+) side of coil. 2. Unplug quick disconnect (with 2 wires) from electric choke heater element. 3. Connect ohmmeter leads to ends of disconnected wires. Replace resistor wire if reading is not within specifications. 4. Reconnect wires to coil and choke. 5. For instructions on replacing resistor wire refer to "Section 3. Part E"\ Engine without Electric Choke 1. Disconnecl wire from positive (+) side of coil. 2. U nplug instrumentation harness from engine harness. 3. Connect one ohmmeter lead to wire removed from coil. Connect other ohmmeter lead to No. 5 pin hole in engine harness. (Figure 8) Replace reistor wire if reading is not within specifications. 4. Reconnect wire to coil. Plug instrumentation harness onto engine harness and tighten retaining clamp securely. 5. For instructions on replacing resistor wire refer to "Section 3. Part E". SPARK PLUGS 1. Inspect each plug individually for badly worn electrodes, glazed, broken or blistered porcelain and replace where necessary. 2. Inspect each spark plug for make and heat range. All plugs must be the same make and number or heat range. Refer to "Specifications" for spark plug numbers. IMPORTANT: Never bend the center electrode to adjust gap. Always adjust by bending ground or side electrode. 3. Adjust spark plug gaps with a round feeler gauge. (Figure 9) Refer to "Specifications" for proper spark plug gap. 3B-24- IGNITION SYSTEM 90-95693 1-888 Clean spark plug sealing area. DO NOT use gaskets on taper seat plugs. Install spark plugs and torque to specifications. \\ here used, gasket must be fully compressed to complete heal transfer and provide a gas-tight seal in cvlinder. For this reason, as well as necessity of maintaining correci plug sap. correct torque is verv important during installation. IMPORTANT: Tapered seat spark plugs are not interchangeable with nontapered (with gasket) spark plugs. HIGH TENSION LEADS 1. Inspect high tension leads for damage. 2. Check high tension leads for continuity. 3. Replace anv leads that are cracked, cut, or have damaged spark plug boots. 4. Replace anv leads that do not show continuity from end to end. a - Porcelain Insulator 5. Reinstall high tension leads in proper order. b - Insulator Cracks Often Occur at this Poin: c-Shell d - Proper Gap IMPORTANT: Proper positioning in high tension lead supports is important to prevent cross firing. e - Side Electrode (File Flat When Adjusting Gap - Do Not Bend) Figure 9. Spark Plug Detail DISTRIBUTOR REPAIR REMOVAL Remove distributor cap (2 screws) and gasket. Do not remove plug wires from cap unless necessary. Disconnect coil primary lead from distributor. Crank or turn engine slowlv. Align liming marks when rotor is pointing to Xo. 1 terminal of distributor cap. If same distributor is to be reinstalled in engine, mark position of distributor housing in relation to engine so that distributor mav be installed in same position. 4. Remove distributor retaining clamp. 5. Remove distributor. IMPORTANT: To simplify distributor installation, DO NOT turn crankshaft with distributor removed from engine. a - Rotor Alignment Notch DISASSEMBLY b - Primary Terminal c - Breaker Point Attaching Screw IMPORTANT: It is not necessary to disassemble d - Breaker Point Adjustment Screw distributor any further than required to complete e - Breaker Plate repairs. Figure 1. Breaker Plate Assembly 1. Lift rotor off of distributor shaft. Remove washer(s) from shaft. (If there are 2 washers, the 2. Remove condenser and breaker points and test as pre- steel washer goes towards housing and the brass washer viously outlined. (Figure 1) 3. Mark breaker plale location and remove 2 retaining screws. towards gear.) Remove breaker plate. (Figure 1) IMPORTANT: Housing bushings are not serviced 4. Remove pin from driven gear and shaft and remove gear separately. (Refer to parts manual.) from shaft. 90-95693 485 IGNITION SYSTEM - 3B-25 6. Check for side play between shaft and housing bushings. Maximum side play is .002" (.05mm). 7. Remove and check shaft for being bent bv placing in \ • blocks and checking run out with a dial indicator. Maximum run out allowed is .002" (.05mm) (retain washer between advance mechanism and distributor housing). 8. Check cam lobes for wear and cam should fit tight on shaft. Advance plate should fit tight on shaft. IMPORTANT: Shaft, advance mechanism and cam are serviced as an assembly and should not be disassembled. (Refer to parts manual). 9. Check advance mechanism for free movement. Mechanism should return freely when released. REASSEMBLY 1. Install washer on shaft assembly and lubricate shaft with engine oil. Install shaft in housing. 2. Install washer(s) on shaft between housing and gear (if there are 2 washers, steel goes toward housing and brass goes toward gear). 3. If installing original driven gear slide onto shaft and install roll pin. IMPORTANT: Hole in gear is offset, gear will fit on shaft and line up with hole only one way. 4. If installing a new driven gear thegear will not comedrilled all the way through. Install gear on shaft. Turn gear to line up the hole with the hole in shaft. Using hole in gear and hole in shaft as a guide, drill through other side of gear with a 3/16" carbide tipped drill, install roll pin. (Figure 2) IMPORTANT: If new gear has only a dimple, you will have to drill through one side of the gear before you slide gear onto shaft. In most cases it is recommended to have a machine shop complete the drilling operation for new gear installation. 5. Install breaker plate using alignment mark to properly locate. 6. Install points, condensor. and primary terminal screw. 7. Install distributor as outlined in "Distributor Installation". mm. • 18372 a - Drill Press c - V-Block b-3/16'Carbide Tip Drill d - New Gear Figure 2. Installing New Gear 3B-26- IGNITION SYSTEM 90-95693 1-888 DISTRIBUTOR INSTALLATION a. Remove No. 1 spark plug and. witn finger on plug hole, ENGINE NOT DISTURBED crank engine until compression is felt in No. 1 cylinder. 1. Install new gasket on distributor housing. 2. Turn rotor approximately '/s-turn in a counterclockwise direction past mark previously scratched on distributor housing. 3. \\ ork distributor down into position in engine block with distributor positioned as noted during removal. IMPORTANT: It may be necessary to move rotor slightly to start gear into mesh with camshaft gear, but rotor should line up with the mark when distributor is down in place. Distributor shaft must enter oil pump shaft for complete installation. 4. Replace and tighten distributor hold-down bolt and clamp. Connect primary lead to coil. Also install spark plug and coil secondary wires, if removed. IMPORTANT: Wires must be installed in supports, to prevent cross-firing. Refer to "Specifications", for firing order. 5. Set point gap and dwell. 6. Install rotor and cap. 7. I ime ignition as outlined under Ignition Timing.' ENGINE DISTURBED 1. Locate No. 1 piston in firing position by either of 2 methods. Continue cranking until pointer lines up with timing mark on crankshaft pulley or . . . b. Remove rocker cover and crank engine until No. 1 intake valve closes, continuing to crank slowly until po nter lines up with timing mark on crankshaft pulley. 2. Position distributor to opening in block in normal installed attitude. 3. Position rotor to point toward No. 1 cylinder on cap (with distributor housing held in installed attitude), then turn rotor counterclockwise approximately '/s-turn more and push distributor dow n to engage camshaft. It may be necessary to rotate rolor slightly until camshaft engagement is felt. 4. While pressing down firmly on distributor housing, engage starter a few limes to make sure oil pump shaft is engaged. Install hold-down clamp and bolt and snug up bolt. 5. Turn distributor body slightly until points just open and tighten distributor clamp bolt. 6. Place distributor cap in position and check that rotor lines up with terminal for No. 1 spark plug. 7. Install cap. distributor primary lead to coil. Check all high tension wire connections and connect spark plug wires, if thev have been removed. W ires must be installed in their proper location in supports to prevent cross-firing. Refer to "Specifications"' for firing order. 8. Set point gap and dwell. 9. Time ignition as outlined under 'Ignition Timing", IGNITION TIMING IMPORTANT: Dwell must be set to specification before adjusting timing. 1. Connect timing light lo No. i spark plug. Connect power supply leads on light to battery (12 volls). Refer to Specification lor cylinder numbering and location. 2. Connect tachometer to engine. 3. Start engine and run at normal idle speed. 4. \im liming light a I timing tab. located on timing gear cover and crankshaft harmonic balancer. 5. \djust timing by loosening distributor clamp and rotating distributor bodv as required until timing mark on balancer or pulley lines up with mark on tab specified iti "Specifications "". Tighten clamp and recheck location of timing mark. 6. Stop engine and remove timing light. IMPORTANT: GM engine timing marks (on iab) are in 2° increments. MCM and MIE L.H. engines will have the "A" (Advance) mark to the left of "O". a - Degree Marks MIE R.H. engines will have the "A" mark to the right b - Timing Marks of "O". Timing must be set on the "A" side of "O" (Top Dead Center). Figure 1. Timing Tab on "GM" V-8 Engine 90-95693 485 IGNITION SYSTEM - 3B-27 THUNDERBOLT IV (HEI) SYSTEM TORQUE SPECIFICATIONS Fastener Location Lbs. Ft. (N.m) Distributor Clamp 3/8-16 20 (27) Spark Plugs (14mm) 15 (20) TOOLS/LUBRICANTS/SEALANTS TOOLS 91-52024A1 Remote Starter Switch 91-63998 Spark Gap Tester 91-99379 Timing Light 91-63209 Torch Lamp 91-99750 Volt/Ohmmeter LUBRICANTS/SEALANTS 92-90018 2-4-C Lubricant 92-41669 Insulating Compound 92-25711 Liquid Neoprene 92-32609 Quicksilver Loctite "A" 3B-28- IGNITION SYSTEM 90-95693 1-888 SPECIFICATIONS UNIT OF MEASUREMENT in. (mm) COIL Coil Part Number 392-7803 Primary Resistance* .60 - .80 Ohms Secondary Resistance* 9.400 11,700 Ohns \OTE: * Use magneto analyzer TIMING Model MCM 898R MCM 228R MCM 260R 330 (B-W) MIE 230 MIE 260 MIE 340 Timing 8° BTDC SPARK PLUGS Model MCM 898R MCM 228R MCM 260R MCM 330 BW MIE 230 MIE 260 MIE 340 Spark Plug Gap .035 (.9) Spark Plug Type AC-MR43T/Champion-RV8C Autolite-144/NGK-BR6FS ELECTRICAL. SYSTEM- 3C-29 90-95693 485 FIRING ORDER FIRING ORDER 1-2-7-5-6-3-4-8 FIRING ORDER Figure 2. MIE 230/260/340 1-8-4-3-6-5-7-2 R.H. (Opposite) Figure 1. MCM 898/228R/260R/330 (B-W) Rotation MIE/230/260/340 L.H. (Standard) Rotation EXAMPLE: On the advance curve chart a 260R DISTRIBUTOR ADVANCE CURVE shows 19° spark advance at 2900 R.P.M. Add 8° BTDC initial timing for a 260R and total spark IMPORTANT: Distributor advance curve charts do advance at 2900 R.P.M. is 25°. not include the initial engine timing. Basic initial timing must be added to chart for total advance IMPORTANT: On the HEI ignition the spark ad- curve. vance is controlled by the amplifier. MCM 898R/228R/260R/330 (B-W) MIE 230/260/340 693-H 3B-30- IGNITION SYSTEM 90-95693 1-888 REPAIR PRECAUTIONS When performing the following procedure, be sure to observe the following. • Be sure that engine compartment is well ventilated and that no gasoline vapors are present, to avoid the possibility of fire. • Be sure to keep hands, feet, and clothing clear of engine moving parts. • Do not touch or disconnect any ignition system parts while engine is running. • Do not reverse battery cable connections. System is negative (-) ground. • Do not disconnect battery cables while engine is running. DISTRIBUTOR CAP a - Alignment Notch Figure 2. R.H. Rotation Wiring 1. Loosen four distributor cap retaining screws. 2. Remove distributor cap. IMPORTANT: If high tension leads are removed from cap refer to Figure 1 or 2. 3. Clean cap with warm soap and water and blow off with compressed air. 4. Check cap contacts for excessive burning or corrosion. Check center contact for deterioration. 5. Check cap for cracks or carbon tracks using Magneto Analyzer. Figure 3. Non Vented Cap a - Alignment Notch Figure 1. L.H. Rotation Wiring 18387 90-95693 485 ELECTRICAL. SYSTEM - 3C-31 18377 a - Vent Figure 4. Vented Cap ROTOR AND SENSOR WHEEL 1. Remove distributor rotor/sensor wheel assembly frcm distributor shaft. Rotor and sensor wheel are Loctited onto shaft. Use two W (10mm) wide flat blade screwdrivers approximately 8" (203mm) to 10" (254mm) long. The screwdrivers are positioned opposite each other with the blade tips on the underside of the rotor and sensor wheel assembly. Make sure blade tips are toward distributor shaft until thev come in contact with shaft. A downward push on both screwdriver handles at the same time will pry rotor and sensor wheel assemblv off. The use of Torch Lamp will also aid in the removal of the rotor/sensor wheel assembly. 2. With the rotor and sensor wheel assembly removed, inspect the locating key inside the rotor. (Figure 5) 3. The locating key will appear as a clean edged. W (3mm) wide, sloped ramp at the bottom of the splined hole. 4. If there are pieces of material shaved off of key or if it appears to have been damaged by being forced down while misaligned with slot ;n distributor shaft, the rotor rr.ust be replaced. 5. Check rotor for burred or corroded center contact. 6. Check rotor for cracks and carbon tracks using magneto analyzer and instructions supplied with analyzer. 7. If rotor is damaged, replace rotor by removing 3 phillips screws and separating sensor wheel from rotor. Reinstall sensor wheel to new rotor making sure locating pin on rotor is installed in locating hole in sensor wheel. Tighten 3 phillips screws securely. (Figure 5) 8. Bend carbon brush tang upward slightly until a distance of !A" (6.5mm) is obtained between rotor and tang. (Figure6) IMPORTANT: if there is any doubt if sensor wheel is located properly, you can lay sensor wheel on top of Figure 5 with sensor fingers facing up (toward you). Line up 3 screw holes and locating pin hole on sensor wheel with Figure. If wheel is indexed properly all the fingers on wheel will line up with the one in the Figure. a - Locating Key b - Phillips Screws c - Sensor Wheel Locating Pin Figure 5. Locating Key Location a -1/4" (6.5mm) Figure 6. Rotor Assembly 9. Put 2 drops of Loctite 271 or Loctite Type "A " into the rotor so it lands on the locating key. (Figure 5) 10. Put 2 drops of Loctite in kevwav on uoper portion of distributor shaft. (Figure 7) 11. Immediately install rotor assembly onto distributor shaft. M AKE SURE rotor locating kev is aligned with keyway in distributor shaft BEFORE pressing rotor all the way down on shaft until it stops with the palm of your hand. Let Loctite cure overnight with distributor in inverted position. IMPORTANT: The rotor should fit very tight. It may be necessary to heat rotor with Torch Lamp to properly install. It is important not to let any Loctite run down distributor shaft. Loctite could get into top distributor housing bushing. 3C-32 - ELECTRICAL SYSTEM 90-95693 1-888 12. Reinstall distributor cap on distributor. 13. Install spark plug wires (if removed) as shown in Figure 1 or 2. Apply a smsill quanity of Insulating Compound to the inside of each spark plug wire boot before installing the boot on distributor cap. ^ ipe off excess. This Insulating Compound will help "waterproof" this area of tne ignition system. IMPORTANT: Make sure boot DOES NOT "hydraulic" back off ol distributor cap terminal. If it does, use needle nose pliers and bend metal spark plug wire terminal (inside of boot) slightly so it grips the distributor cap terminal tighter. IMPORTANT: Black boot is distributor end of spark plug wire. Gray (or Red) boot is spark plug end of wire. SENSOR 1. Remove rotor and sensor wheel. 2. Remove2 screws that hold sensor into distributor housing. (Figure 7) 3. Remove sensor from housing. Figure 8. Location of Cracks in Metal Jumper Leads on Ignition Sensor DO NOT USE any type of silicone sealer on the inside of the distributor. Most silicone sealers give off an acidic vapor during the curing stage of the sealer. This acidic acid can cause corrosion on the ignition components. 5. Install sensor into housing and install 2 retaining screws. 6. Install sensor wheel, rotor, and distributor cap. 15225 SPAR K PLUG S a Mounting Screws d Sensor Assembly 1. Inspect each plug individually for badlv worn electrodes, Figure 7 glazed, broken or blistered porcelain and replace where necessary. 4. Use a good magnifying glass and light to inspect the two 2. Inspect each spark plug for make and heat range. All plugs metal "jumper leads" for cracks (Figure 8). If a crack is must be the same make and number or heat range. Refer to found in either metal "jumper lead . install a new sensor. "Specifications" for spark plug numbers. 90-95693 485 ELECTRICAL. SYSTEM - 3C-33 IMPORTANT: Never bend the center electrode to adjust gap. Always adjust by bending ground or side electrode. 3. Adjust spark plug gaps with a round feeler gauge. (Figure9) Refer to "Specification"' for proper spark plug gap. b - Insulator Cracks Often Occur at this Point c - Shell d - Proper Gap e - Side Electrode (Berd to Adjust Gap) f - Center Electrode (File Flat When Adjusting Gap - DO NOT Bend) Figure 9. Spark Plug Detail 4. Clean spark plug seating area. DC) NOT use gaskets on taper seat plugs. Install spark plugs and torque to specifications. Where used, gasket must be fully compressed to complete heat transfer and provide a gas-tight seal in cylinder. For this reason, as well as necess.lv of maintaining correct plug gap. correct torque is very important during installation. IMPORTANT: Tapered seat spark plugs are not interchangeable with nontapered (with gasket) spark plugs. HIGH TENSION LEADS 1. Inspect high tension leads for damage. 2. Check high tension leads for continuitv. 3. Replace anv leads that are cracked, cut. or have damaged spark plug boots. 4. Replace anv leads thai do not show continuitv from end to end. 5. Reinstall high tension leads in proper order. IMPORTANT: Proper positioning in high tension lead supports is important to prevent cross-firing. IMPORTANT: Black boot is distributor end of spark plug wire. Gray (or Red) boot is spark plug end of wire. DISTRIBUTOR REPAIR REMOVAL 1. Remove distributor cap. Do not remove high tension leads unless necessary. 2. Crank engine over until timing marks line up and rotor is pointing towards No. 1 cylinder on distributor cap. 3. Mark distributor housing in reference to engine block. 4. Remove bolt and hold down clamp and remove distributor. IMPORTANT: To simplify distributor installation, DO NOT turn crankshaft with distributor removed from engine. DISASSEMBLY 1. Remove rotor, sensor wheel, and sensor as previously outlined. 2. Remove roll pin. washer and driven gear from distributor shaft. 3. Check for side play between shaft and distributor housing bushings. Maximum side plav is .002" (.05mm). 4. Remove shaft from housing and check shaft for being benl with a dial indicator and \-blocks. Maximum runout is .002" (0.5mm). REASSEMBLY 1. Lubricate shaft with engine oil. Install "K" clip (if removed) on shaft. Install shaft in housing. 2. Install washer on shaft. Install original gear slide onto shaft and install roll pin. IMPORTANT: Hole may be offset and gear will only fit in one direction. 3. If installing a new gear, the gear will come drilled on one side. Slide gear onto shaft, line hole in gear with hole in shaft. I sing these holes as guides, drill through other side of gear with a 3/16" carbide lipped drill. 3C-34 - ELECTRICAL SYSTEM 90-95693 1-888 18372 a - Drill Press b -3/16" Carbide Tip Drill c - V-Block d - New Gear Figure 1. Drilling New Gear 4. Install sensor, sensor wheel, and rotor as previously outlined. 5. Install distributor as outlined in "Distributor Installation". DISTRIBUTOR ENGINE NOT DISTURBED 1. Install new gasket on distributor housing. 2. Turn rotor approximately '/s-turn in a counterclockwise direction past mark previously scratched on distributor housing. 3. Work distributor down into position in engine block with distributor positioned as noted during removal. IMPORTANT: It may be necessary to move rotor slightly to start gear into mesh with camshaft gear, but rotor should line up with the mark when distrib- IMPORTANT: Early HEI Ignition systems had 2 vents in distributor housing. Later ignition systems and all replacement housings have 4 vents. (Figure 2) a -2 Vent Type b - Added These Vents to Make Distributor a 4 Vent Type Figure 2. HEI Distributor Base DO NOT DRILL additional vent holes or modify 2 venl type distributor in any way to try and make it a 4 vent type. INSTALLATION utor is down in place. Distributor shaft must enter oil pump shaft for complete installation. 4. Replace and tighten distributor hold-down bolt and clamp. Connect leads. Also install spark plug and coil secondary wires, if removed. IMPORTANT: Wires must be installed in supports, to prevent cross-firing. Refer to "Specifications", for firing order. 5. Install cap. 6. Time ignition as outlined under "Ignition Timing". 90-95693 485 ELECTRICAL. SYSTEM - 3C-35 ENGINE DISTURBED 1. Locate No. 1 piston in firing position by either of 2 methods described below. a. Remove No. 1 spark plug and. with finger on plughole, crank engine until compression is felt in No. 1 cylinder. Continue cranking until pointer lines up with timing mark on crankshaft pulley or . . . b. Remove rocker cover and crank engine until No. 1 intake valve closes, continuing to crank slowly until pointer lines up with timing mark on crankshaft pulley. 2. Position distributor to opening in block in normal installed attitude. 3. Position rotor to point toward No. 1 cylinder on cap (with distributor housing held in installed attitude), then turn IGNITION 1. Connect timing light lo No. 1 spark plug. Conncect power supplv leads on light to battery (12 volts). Refer to "Specifications" for cylinder numbering and location. 2. Connect tachometer to engine. 3. Start engine and run at normal idle speed. 4. Aim timing light at timing tab. located on timing gear cover and crankshaft harmonic balancer. 5. Adjust timing by loosening distributor clamp and rotating distributor body as required until timing mark on balancer or pullev lines up with mark on tab specified in "Specifications" . Tighten clamp and recheck location of timing mark. 6. Stop engine and remove timing light. IMPORTANT: GM engine timing marks (on tab) are in 2° increments. MCM and MIE L.H. engines will have "A" (Advance) mark to the left of "O". MIE R.H. engines will have the "A" mark on the right of "O". Timing must be set on the "A" side of "O" (Top Dead Center). rotor counterclockwise approximately '/s-turn more and push distributor down to engage camshaft. It may be necessarv to rotate rotor slightly until camshaft engagement is felt. 4. While pressing down firmly on distributor housing, engage starter a few times to make sure oil pump shaft is engaged. Install hold-down clamp and bolt and snug up bolt. 5. Place distributor cap in position and check :hat rotor lines up with terminal for No. 1 spark plug. 6. Install cap and distributor leads. Check a.I high tension wire connections and connect spark plug wires, if they have been removed. Wires must be installed in their proper location in supports to prevent cross-firing. Refer to "Specifications" for firing order. 7. Time ignition as outlined under "Ignition Timing". TIMING a - Degree Marks b - Timing Mark Figure 1. Timing Tab on "GM" V-8 Engine 3B-36- IGNITION SYSTEM 90-95693 1-888 THUNDERBOLT IV TESTING 90-95693 485 ELECTRICAL. SYSTEM - 3C-37 SECTION 3 - ELECTRICAL SYSTEM PART C - CHARGING SYSTEM INDEX IdentificationReplacement Parts WarningDrive Belt Tension Adjustment Alternator Seawater Pickup Pump Power Steering Pump MOTOROLA ALTERNATOR Torque SpecificationsTools/SealantsSpecificationsDescriptionPrecautionsPeriodic MaintenanceTroubleshooting Tests (Alternator on Engine) Circuitry Test Output Circuit Excitation Circuit Sensing Circuit Current Output Test Voltage Output Test Alternator RepairRemovalDisassemblyCleaning and InspectionComponent Testing Rotor Stator Rectifier Diodes Diode Trio Condenser Reassembly InstallationDELCO ALTERNATOR Torque SpecificationsTools/SealantsSpecificationDescriptionPrecautionsPeriodic MaintenanceTroubleshooting Tests (Alternator on Engine) Voltage Regulation Test Current Output Test Circuitry Test Output and Ground CircuitExcitation Circuit (3-Wire Alternator Only) Sensing Circuit (3-Wire Alternator Only) Alternator Repair Removal Disassembly Cleaning and Inspection Component Testing Upper Brush Lead Clip and Regulator Ground Test Page 3C-1 3C-2 3C-3 3C-3 3C-3 3C-3 3C-5 3C-5 3C-6 3C-6 3C-7 3C-7 3C-7 3C-8 3C-8 3C-9 3C-9 3C-9 3C-10 3C-11 3C-11 3C-12 3C-13 3C-13 3C-13 3C-14 3C-14 3C-15 3C-15 3C-15 3C-17 3C-18 3C-18 3C-19 3C-19 3C-20 3C-20 3C-20 3C-20 3C-22 3C-23 3C-23 3C-24 3C-25 3C-26 3C-26 3C-28 3C-28 3C-29 3C-29 Page Rotor 3C-29 Stator 3C-30 Rectifier Bridge 3C-30 Diode Trio 3C-31 Regulator Terminal Connector (3-Wire Alternator Only) 3C-31 Capacitor 3C-32 Reassembly 3C-32 Installation 3C-33 MANDO ALTERNATOR Torque Specifications 3C-34 Tools/Sealants 3C-34 Specifications 3C-35 Description 3C-35 Precautions 3C-36 Periodic Maintenance 3C-36 Troubleshoot ng Tests (Alternator on Engine) 3C-36 Circuitry Test 3C-37 Output Circuit 3C-37 Excitation Circuit 3C-37 Sensing Circuit 3C-37 Current Output Test 3C-38 Voltage Output Test 3C-38 Alternator Reoair 3C-40 Removal 3C-40 Disassembly 3C-40 Cleaning and Inspection 3C-42 Component Testing 3C-43 Rotor 3C-43 Stator 3C-43 Negative (-) Rectifier Diodes 3C-44 Positive (+) Rectifier Diodes and Diode Trio 3C-44 Condenser 3C-45 Reassembly 3C-45 Installation 3C-46 470/485/488 CHARGING SYSTEM Torque Specifications 3C-47 Tools/Sealants 3C-47 Specifications 3C-47 Description 3C-48 Precautions 3C-48 Periodic Maintenance 3C-48 Removal/Installation 3C-48 Troubleshooting Test (On Engine) 3C-49 Constant High Output 3C-49 No Output 3C-49 Voltage Regulator Test 3C-50 BATTERY ISOLATORS Dual Battery Charging Systems Using a Battery Isolator 3C-51 MCM/MIE 470/MCM 485/488 3C-51 All Other Models 3C-51 IDENTIFICATION 04881 a - Output Terminal b - Delco Number Figure 1. Delco 1-Wire a - Output Terminal b - 2 Wires Going to Engine Harness c - Delco Number Figure 2. Delco 3-Wire 11580 a - 2 Wires Going to Engine Harness Coming Out the Top a - 2 Wires Going to Engine Harness Coming Out the Side of Regulator of Regulator b - Mando Number b - Motorola Number Figure 4. Mando Figure 3. Motorola 90-95693 485 ELECTRICAL. SYSTEM - 3C-1 a - Pulley a - Pulley b - Exposed Cooling Fins-Do Not Use This Alternator On MIE R.H. b - Covered Cooling Fins - this Alternator Can Be Used on All (Opposite) Rotation Engines Engines Figure 5. Uni-Rotational Alternator - Used in Figure 6. Bi-Rotational Alternator - Used in Production Production on All MCM and MIE L.H. on MIE R.H. (Opposite) Rotation Engines (Standard) Rotation Engines and as Service Replacement REPLACEMENT PARTS WARNING Electrical, ignition and fuel system components on your MerCruiser are designed and manufactured to comply with U.S. Coast Guard Rules and Regulations to minimize risks of fire and explosion. Use of replacement electrical, ignition or fuel system components, which do not comply with these rules and regulations, could result in a fire or explosion hazard and should be avoided. IMPORTANT: Alternators are equipped with an excitation circuit. This circuit will have approximately a 7 mills amp draw on the battery with the ignition key in the off position. This draw is normal. 3C-2 - ELECTRICAL SYSTEM 90-95693 1-888 DRIVE BELT TENSION ADJUSTMENT 2. If a new drive belt has been installed, recheck belt tension after running for 5 minutes. ALTERNATOR 1. Install drive belt on pullevs and adjust tension as follows. (Figure I) a. Pivot alternator away from engine, as required, until POWER STEERING PUMP correct tension is obtained as shown in Figure 1. b. After obtaining correct tension, securely retighten IMPORTANT: DO NOT pry on pump with pry baror alternator brace attaching bolts and alternator mount-screwdriver. ing bolls. 1. Install drive belt on pullevs and adjust tension as follows. (Figures 3. 4. 5.6. 7 or 8)' a. Pivot pump away from engine, as required, until correct tension is obtained as shown. b. After obtaining correct tension, securely retighten pump brace and pump mounting bolts. 2. If a new drive belt has been installed, recheck bell tension after running for 5 minutes. a - Belt Should Depress 1/2" (13mm) Figure 1. Alternator Drive Belt Tension 2. If a new drive bell has been installed, recheck belt tension a - Belt Should Depress 1/4" (6mm) afler running for 5 minutes. Figure 3. MCM 120/140/165 SEAWATER PICKUP PUMP I. Install drive bell on pullevs and adjust tension as follows. (Figure 2) a. Pivol pump awa\ from engine, as required, until correel tension is obtained as shown in Figure 2. b. After obtaining correct tension, securelv retighten pump brace and pump mounting bolts. a - Belt Should Depress 1/4" (6mm) Figure 2. Seawater Pump Drive Belt Tension 90-95693 485 a - Belt Should Depress 1/4" (6mm) Figure 4. MCM 898/228/260/330 With Low Mounted Pump ELECTRICAL. SYSTEM - 3C-3 a - Belt Should Depress 1/4" (6mm) Figure 7. Hi-Performance Power Steering Models a - Belt Should Depress 1/4" (6mm) a - Belt Should Depress 1/2" (13mm) Figure 6. MCM 330 (B-W) Figure 5. MCM 898/228/260 With High Mounted Pump 15492A 16218 a Belt Should Depress 1/4" (6mm) Figure 8. MCM 470/485/488 90-95693 1-888 3C-4 - ELECTRICAL SYSTEM MOTOROLA ALTERNATOR TORQUE SPECIFICATIONS Fastener Location Lbs. Ft. (N.m) Lbs. In. (N.m) Alternator Brace To Alternator 192 (28) Alternator Brace To Block 30 (41) Alternator To Mounting Bracket 35 (48) Alternator Mounting Bracket 30 (41) Brush Retaining Screws Securely Diode Trio Studs Securely Pulley Nut 50 (68) Rectifier Diode Studs Securely Regulator Retaining Screws Securely Slip Ring Retaining Bolt Securely Thru Bolts Securely TOOLS/SEALANTS MERCURY MARINE SPECIAL TOOLS 91 -31229A5 Bearing Removal and Installation Kit 91 -76032 Magneto Analyzer 91 -37241 Universal Puller Plate 91 -99750 Volt/Ohmmeter 90-95693 485 ELECTRICAL. SYSTEM - 3C-5 SPECIFICATIONS Mercury Number (Motorola Number) Amp Output (Max.) Rotation 78402 (8MR2024F) 37 Bi-Rotational 78403 (8MR2023F) 37 Uni-Rotational 92497 (8MR2039K) 55 Bi-Rotational 92498 (8MR2036K) 55 Uni-Rotational DESCRIPTION The alternator system, used on engines with Motorola Alternators, consists of the alternator, battery, the ignition switch and the wiring which connects these components. Refer to "Seclion 3 Part F" for wiring diagrams. The alternator employs a rotor, which is supported in 2 end frames by ball bearings, and is driven (via a pulley) at approximately twice engine speed. The rotor contains a field winding that is enclosed between 2 multiple-finger pole pieces. The ends of the field w inding are connected to 2 insulated slip rings on the rotor shaft. Current is supplied to the field w inding by 2 brushes (mounted in the rear end frame) w hich make continuous sliding (or slipping) contact with the slip rings. The current (flowing through the field winding) creates a magnetic field that causes the adjacent fingers of the pole pieces to become alternate north and south magnetic poles. \ 3-phase stalor is mounted directlv over the rotor pole pieces and between I he 2 end frames. It consists of 3 windings wound 120° electrically out-of-phase on ihe inside of a laminated core. The windings are all connected together on one end. while the other ends are connected to a full-wave rectifier bridge. The rectifier bridge contains 6 diodes which are arranged so thai current flows from ground, thru the stator and to the output terminal, but not in the opposite direction. When current is supplied to the rotor field winding, and the rotor is turned, the movement of the magnetic fields created induces an alternating current into the stator windings. The rectifier bridge then changes this alternating current to direct current which appears at the output terminal. A diode trio also is connected to the stator windings to supply current to the regulator and the rotor field during operation Voltage output of the alternator is controlled by regulating the current supplied to the rotor field. This is accomplished by a transistorized voltage regulator that senses the voltage at the battery and regulates the field current to maintain alternator voltage within prescribed limits for properly charging the batterv. Current output of the alternator does not require regulation, as maximum current output is self-limited by the design of the alternator. As long as the voltage is regulated w ithin the prescribed limits, the alternator cannot produce excessive current. A cutoul relay in the voltage regulator also is not required, as the the rectifier diodes (which allow current to flow in one direction only) prevent the batterv from discharging back through the stator. Due to the lack of residual magnetism in the rotor pole pieces, a small amount of current must be supplied to the rotor field to initially start the alternator charging. This is accomplished by means of an excitation circuit in the regulator which is connected to the ignition switch. Once the alternator begins to produce output, field current is supplied solely by the diode trio, as explained, preceding. The alternator also is equipped with a fan (mounted on the rotor shaft) which induces air flow through the alternator to remove the heat created by the rectifier and stator. A capacitor also is utilized to protect the rectifier system from high voltages and to suppress radio noise. 3C-6 - ELECTRICAL SYSTEM 90-95693 1-888 PRECAUTIONS The following precautions MUST BE observed when working tor terminal when the alternator is being driven by the on the alternator system. Failure to observe these precautions engine. mav result in serious damage to the alternator or alternator 5. ALWAY S remove negative (-) battery cable from battery system. before working on alternator svstem. 1. DO NOT attempt to polarize the alternator. 6. When installing battery. BE SURE to connect the negative 2. DO NOT short across or ground any of the terminals on the (-) (grounded) battery cable to negative (-) battery termialternator, except as specifically instructed in the Trounal and the positive (+) battery cable to positive (+) batterv bleshooting Test". termina.. 3. NEVER disconnect the alternator output lead or battery 7. If a charger or booster battery is to be used. BF. SI RE to cables when the alternator is being driven by the engine. connect it in parallel with existing battery (positive to 4. NEVER disconnect regulator lead from alternator regulapositive, negative to negative). PERIODIC MAINTENANCE The following maintenance check should be performed everv 50 hours or 60 days (whichever comes first) in fresh water areas or every 25 hours or 30 days in salt water areas. 1. Inspect entire alternator system for corroded or loose connections. 2. Check wiring for frayed or worn insulation. 3. Check alternator drive belt for excessive wear, cracks, fraving and glazed surfaces. Also, check drive belt tension and adjust, if necessarv, as explained under "Drive Belt Tension Adjustment". 4. Check alternator mounting bolts for adequate tightness. 5. Inspect slip ring end frame flame arrestor screen for debris and clean, if necessary, using compressed air or a cloth. Screen Ml ST BE clean, or alternator mav overheat. TROUBLESHOOTING TESTS (ALTERNATOR ON ENGINE) Use the following tests in conjunction with the "Troubleshootoutlinec in "Section 3 Part A". Batterv MUST BE at least ing" in Section 1. Before proceeding with the tests, however, 75% (1.230 specific gravity) of fully charged toobtain valid perform the following checks to eliminate possible problem results in the following tests. If not, charge battery before areas. Also observe "Precautions", immediately preceding, to testing system. prevent damage to alternator system. 3. Inspect entire alternator system wiring for defects. Check 1. If problem isan undercharged battery,check to ensure that all connections for tightness and cleanliness, particularly undercharged condition has not been caused by excessive battery cable clamps and battery terminals. accessory current draw or by accessories which have 4. Check alternator drive belt for excessive wear, cracks, accidentally been left on. Also, check that undercharged fraving and glazed surfaces and replace if necessary. Also, condition has not aeen caused by running engine at too low check drive belt tension and adjust if necessary, as outlined a speed for extended periods of time. under "Drive Belt Tension Adjustment", preceeding in 2. Check physical condition and state of charge of battery, as this section. 90-95693 485 ELECTRICAL. SYSTEM - 3C-7 CIRCUITRY TEST Perform the following tests, using a 0-20 volt DC voltmeter, to check that all of the circuits between the alternator and the other components within the alternator system are in good condition. Output Circuit 1. Connect positive voltmeter lead to alternator output terminal and negative lead to a ground terminal on alternator. (Figure 1) 2. Wiggle engine wiring harness while observing voltmeter. Meter should indicate approximately battery voltage and should not vary. If no reading is obtained, or if reading varies, check alternator output circuit for loose or dirty connections or damaged wiring. b - Excitation Wire - Purple (White; c - Sensing Wire - Red/Purple (Red) d - Volt Meter (0-20 Volts) Figure 1. Alternator Output Circuit Test a - Output Wire - Orange (Red/White) c - Sensing Wire - Red/Purple (Red) b - Excitation Wire - Purple (White) d - Volt Meter (0-20 Volts) Figure 2. Alternator Excitation Circuit Test 3C-8 - ELECTRICAL SYSTEM 90-95693 1-888 Excitation Circuit Connect positive (+) voltmeter lead to regulator terminal on alternator and negative (-) lead to a ground terminal on alternator. (Test No. 1 in Figure 2) Turn ignition switch to "On " position and note voltmeter reading. Reading should be 1.5 to 2.5 volts. 3. If no reading is obtained, an opening exists in alternator excitation lead or in excitation circuit of regulator. 1 nplug purple (or white) lead from regulator. Connect positive voltmeter lead to purple (or white) lead and negative voltmeter lead to ground. (Test No. 2 in Figure 2) If voltmeter now indicates approximate battery voltage, voltage regulator is defective and must be replaced. If no voltage is indicated, check excitation circuit for loose or dirty- connections or damaged wiring. If reading is between .75 and 1.1 volts, rotor field circuit probablv is shorted or grounded. Disassemble alternator and test rotor as outlined under "Alternator Repair". following If reading is between 6.0 and 7.0 volts, rotor field circuit probablv is open. Remove regulator and inspect for worn brushes or dirty slip rings. Replace brushes if less than lA" (6mm) long. If brushes and slip rings are in good condition, disassemble alterntor and test rotor, as outlined under "Alternator Repair". 6. If reading is between 8.5 and 10.0 volts, an open probably exists in load circuit of regulator. To be certain that this is the problem, remove 4 screws which secure the regulator to the alternator. Connect a jumper wire between regulator terminal and field (brush) terminal. (Figure 3) DO NOT allow jumper lead to touch alternator housing. Repeat test. If jumper wire provides correct voltmeter reading (1.5 to 2.5 volts), voltage regulator is faulty and must be replaced. a - Jumper Wire Connected between Regulator Terminal and Field (Brush) Terminal b - Use Insulators to Prevent Wire from Contacting Alternator Figure 3. Checking for Faulty Regulator Load Circuit Sensing Circuit I. nplug red/purple (or red) lead from voltage regulator. Connect positive voltmeter lead to red/purple (or red) lead and negative voltmeter lead to ground terminal. (Figure 4) Voltmeter should indicate batterv voltage. If battery voltage is not present, check sensing circuit [red/purple (or red) leac] for loose or dirty connections or damaged wiring. a - Output Wire - Orange (Red/White) b - Excitation Wire - Red/Purple (Red) c - Sensing Wire - Purple (White) d - Volt Meter (0-20 Volts) Figure 4. Regulator Sensing Circuit Test CURRENT OUTPUT TEST Perform this lest to check if alternator is capable of producing rated current output, using a 0-50 amp DC ammeter. Be sure that engine compartment is well- ventilated and that there are no gasoline vapors present (during the test) to prevent the possibility of an explosion and/or a fire, should a spark occur. 1. Disconnect negative (-) battery cable from batterv. 2. Disconnect orange (or red/white) lead from alternator output terminal and connect ammeter in series between lead and output terminal. (Figure 7) Connect positive (+) side of ammeter toward output terminal. 3. Reconnect negative battery cable. 4. Remove coil hi-tension lead from distributor cap tower and ground it to block. Turn on all accessories and crank engine over with starter motor for 15-20 seconds. 90-95693 485 ELECTRICAL. SYSTEM - 3C-9 5. Turn off accessories and reinstall coil hi-tension leac. Start engine and adjust engine speed to 1500-2000 RPM. Quickly observe ammeter. Reading should be at least 30 amps. 6. If reading is low. stop engine and connect a jumper wire between alternator output terminal and regulator terminal. (Figure 5) Repeat Steps 4 and 5. 7. If reading is now within specifications, diode trio is faultv. Disassemble alternator and replace diode trio, as explained under "Alternator Repair", following. 8. If reading is still low with jumper wire connected, perform "Voltage Regulator Test", following, to determine if fault is in regulator or alternator. a - Output Wire - Orange (Red/White) b - Excitation Wire - Purple (White) c - Sensing Wire - Red/Purple (Red) d - Jumper Wire For Testing Diode Trio e - Ammeter (0-50 Amps) Figure 5. Alternator Current Output Test VOLTAGE OUTPUT TEST Perform this test to determine if voltage regulator is operating correctlv. using a 0-20 volt DC volmeter. IMPORTANT: Battery MUST BE fully charged (1.260 or above specific gravity) to obtain proper voltage reading in this test. If necessary, charge battery with a battery charger or allow engine to run a sufficient length of time to fully charge battery before taking reading. 1. Connect positive (+) voltmeter lead to positive batterv terminal and negative (-) voltmeter lead to negative terminal. (Figure 6) 2. Start engine and run at last idle until engine reaches normal operating temperature. Adjust engine speed to 1500-2000 RPM and observe voltmeter for highest reading. Reading should he netween 13.9 and 14.7 volts. 3. If reading i-high, check for a loose or dirty regulator ground lead connection. I( connection isgood (and sensing circuit checked out good in "Alternator Svstern Circuitry Test"), voltage regulator is faultv and must be replaced. Be sure to disconnect battery cables before attempting to remove regulator. Be sure that engine compartment is well- ventilated and that there are no gasoline vapors present (during the next steps) to prevent the possibility of an explosion and/or fire, should a spark occur. DO NOT allow jumper wire to contact alterna tor end frame (in next step), as diode trio and regulator may be damaged. 4. If reading is low, .stop engine and remove 4 regulator attaching screws. Pull regulator away from alternator end frame to gain access to field terminal. DO NOT disconnect regulator leads. Connect a jumper wire between field (brush) terminal and regulator terminal. (Figures 5 and 8) Restart engine and graduallv increase engine speed to 1500 RPM while observing voltmeter. DO NOT allow voltage to exceed 16 volts. 5. If a voltmeter reading of 14.5 volts cr above is now obtained, voltage regulator is faulty and must be replaced. If voltmeter reading is below 14.5 volts, inspect brushes and slip rings for wear, dirt or damage. If brushes and slip rings are good, alternator is faulty internally. Disassemble alternator and lest components, as outlined under "Alternator Repair", following. a - Output Wire - Orange (Red/White) b - Excitation Wire - Purple (White! c - Sensing Wire - Red/Purple (Red) d - Jumper Wire To Eliminate Regulator e - Volt Meter (0-20 Volts) Figure 6. Voltage Regulator Test 3C-10 - ELECTRICAL SYSTEM 90-95693 1-888 ALTERNATOR REPAIR REMOVAL 4. Loosen alternator brace to engine attaching bolt and alternator mounting bolt, then pivot alternator inward and 1. Disconnect negative (-) batterv cable from batterv. remove alternator drive belt. 2. Disconnect wiring harness from alternator. 5. Remove alternator mounting bolt, washers (if used), 3. Remove alternator brace to alternator attaching bolt. spacer and nut and remove alternator. washer(s) and spacer (if used). 1 - Screw (2) 2 - Screw (2) 3 - Regulator 4 - Felt Seal 5 - Bolt (4) 6 - Screw (2) 7 - Brush Set 8 - Nut (2) 9 - Lockwasher (2) 10 - Nut (Self-Locking) 11 - Flat Washer 12 - Insulating Washer (2) 13 - Insulating Washer (2) 14 - Flat Washer 15 -Lockwasher 16 - Nut 17 - Nut (Self-Locking) (2) 18 - Condenser 19 - End Frame 20 - Bearing Retainer 21 - Insu ator 22 - Insu ator 23 - Negative Rectifier Diode Set 24 - Positive Rectifier Diode Set 25 - Diode Trio 26 - Stator 27 - Screw 28 - Lockwasher 29 - Flat Washer 30 - Slip Ring 31 - Bearing (2) 32 - Rotor 33 - Bearing Retaining Ring 34 - End Frame 35 - Nut (4) 36 - Spacer 37 - Key 38 - Fan iBi-Rotational Shown) 39 - Pulley 40 - Lockwasher 41 - Nut Figure 1. Motorola Alternator Parts View 90-95693 485 ELECTRICAL. SYSTEM - 3C-11 DISASSEMBLY IMPORTANT: The following instructions are for complete disassembly and overhaul of the alternator. In many cases, however, complete disassembly of alternator is not required and, in those cases, it is necessary only to perform the operations required to repair or replace the faulty part. Mount alternator in a vise so that rear end frame is facing you. Disconnect 2 regulator leads from terminals on rear end frame. Remove 4 regulator attaching screws, then pull regulator away from rear end frameand disconnect regulator field lead. Remove regulator felt seal. Remove 2 brush set attaching screws and remove brush set. Scribe a mark on rear end frame, stator and front end frame to ensure proper reassemblv later. Remove 4 thru bolts and nuts which secure end frames and stator together. IMPORTANT: DO NOT insert screwdriver blades more than 1/16" (1.6mm) into openings (in next step), as stator windings may be damaged. Separate rear end frameand stator assembly from front end frame and rotor assembly by carefully inserting 2 screw drivers into opposite openings between stator and front end frame and prying units apart. (Figure 2) Remove (and discard) bearing retaining ring from rear end frame bearing bore. 9. Unsolder stator and diode trio leads from rectifier diode terminals. Place a needle-nose pliers or. diode terminal between solder joint and diode bodv (as shown in Figure3) to help prevent heat damage to diodes. I nsolder joints as quicklv as possible and allow diode terminal to cool before removing pliers. a - Diode Terminal b - Place Needle-Nose Pliers between Solder Joint and Diode Body c - Place Rubber Bands around Pliers Handles to Allow Use of Both Hands dur ng Unsoldering Operation Figure 3. Unsoldering Stator and Diode Trio Leads from Rectifier Diodes 10. Remove diode trio from positive rectifier heat -ink. 11582 a - DO NOT Insert Screwdriver Blades More Than 1/16" into Openings Figure 2. Separating Rear End Frame and Stator Assembly from Front End Frame and Rotor Assembly 8. Place rear end frame and stator assemblv on the bench with stator downward. Be sure that bench is clean and free of melal chips. Remove nuts, washers, insulators and condenser from rectifier mounting studs and lift rear end frame from studs. Remove2 insulating sleeves and washers from rectifier studs. IMPORTANT: With alternator disassembled to this point, stator, rectifier diodes, diode trio and rotor may be tested, as explained under "Component Testing". IMPORTANT: DO NOT clamp vise on rotor pole pieces when removing pulley nut (in next step), as pole pieces may be distorted. a - Wrench b - Use Oversize V-Belt to Protect Pulley Figure 4. Removing Pulley Nut 3C-12 - ELECTRICAL SYSTEM 90-95693 1-888 11. Remove pullev retaining nut bv clamping pullev in a vise (using an old oversize \ belt or protective jaws to protect pulley) and turning nut counterclockwise with a wrench. (Figure 4) Remcve lockwasher and slide pulley and fan from shaft. If pulley is "stubborn", it mav be necessarv to use an universal pullers. 12. Remove kev from rotor shaft with a diagonal pliers, then slide fan spacer from shaft. IMPORTANT: DO NOT remove front end frame from rotor shaft, unless absolutely necessary, as front bearing MUST BE replaced, if it is removed. 13. I sing a long-nose pliers, compress ears of front bearing retainer and lift retainer free of recess in front end frame. (Figure 5) Tap pulle\ end of rotor shaft with a rawhide mallet to remove rotor and front bearing assembly from front end frame. 14. Remove front bearing from rotor shaft with I niversal Puller Plate and an arbor press, as shown in Figure 6. (Discard bearing.) a - Compress Ears of Retainer and Lift Figure 5. Removing Front Bearing Retainer from Recess 11585 11586 a - Universal Puller Plate Figure 6. Removing Front Bearing from Rotor Shaft 90-95693 485 15. If rotor slip rings or rear bearing require replacement, carefullv unsolder rotor field winding leads from slip ring terminals and unwind end of leads. Remove slip ring attaching screw. lockwasher and flat washer and slide slip rings from shaft. 16. If rear bearing requires replacement, remove bearing from rotor shaft with I niversal Puller Plate and arbor press. Bearing Ml ST BE replaced, if removed. CLEANING and INSPECTION 1. Clean all parts with a clean, soft cloth. DO NOT use solvent, or electrical components mav be damaged. 2. Inspect the following parts for wear and damage: a. Brush set - inspect for cracked porcelain casing, damaged brush leads, poor brush lead solder connections. weak or broken brush springs or worn brushes. Replace brush set if brushes are less than lA" (6mm) long. b. Rotor - inspect for stripped threads, worn kevwav. scuffed pole piece fingers or damaged bearing surfaces (because of bearing turning on shaft). c. Rotor slip rings - clean slip rings with 400 grain (or finer) polishing cloth while spinning rotor in a lathe. Blow offdust with compressed air. Inspect slip rings for grooves, pits, flat spots or out-of-rounders | .002" (.05mm) maximum] and replace, if present. d. Rotor shaft bearings - inspect for damaged seals, lack of lubrication, discoloration (from overheating) or excessive side or end play. Hold inner race of bearings while turning outer race. Bearing should turn freelv without binding or evidence of rough spots. e. Stator - inspect for damaged insulation or wires: also inspect insulating enamel for heat discoloration: as this is usually a sign of a shorted or grounded w inding or a shorted diode. f. Regulator - inspect leads for damaged insulation. g. Front and rear end frames - inspect for cracks, distortion, stripped threads or wear in bearing bore (from bearing outer race spinning in bore). End frame(s) ML ST BE replaced, if bearing has spun. Also. inspect bearing retainer recess in front end frame for damage. h. Fan - inspect for cracked or bent fins, broken welds (bi-rotationa! fan only) or worn mounting hole (from fan spinning on shaft). i. Pulley - inspect pulley mounting bore and key groove for wear. Inspect drive surface of pullev sheaves for trueness. excessive wear, grooves, pits, nicks or corrosion. Repair damaged surfaces, if possible, with a fine file and a w ire brush or replace pullev. if bevond repair. Drive surfaces Ml ST BE perfecth Irue and smooth.or drive belt wear will begreally accelerated. COMPONENT TESTING Rotor 1. Test rotor field circuit forgrounds. using an ohmmeter (set on Rxl scale), as follows: a. Connect one lead of ohmmeter to either slip ring and the lead to rotor shaft or pole pieces. (Figure 7) b. Meter should indicate no continuity (meter should not move). c. If continuity doesexist. rotor field circuit isgrounded. Inspect slip ring terminals to be sure thai lhe\ are not benl and touching rolor shaft. Also be sure thai excess ELECTRICAL. SYSTEM - 3C-13 solder is no! grounding terminals to rotor shaft. If cause for ground cannot be found, unsolder field winding leads from slip ring terminals and connect ohmmeter between one of the leads and rotor shaft or pole pieces. If continuity still exists, replace rotor assemblv. If continuity is eliminated, replace slip rings. b - Test for Opens Shorts or High Resistance Figure 7. Testing Rotor Field Circuit Test rotor field circuit for opens, shorts or high resistance, using an ohmmeler (set on Rxl scale), as follows: a. Connect one ohmmeter lead to each slip ring. {Figure 7) b. Ohmmeter reading should be 4.2 to 5.5 ohms with rotor at room temperature |70° - 80° F (21° • 26° C)]. c. If reading is high or infinite (no meter movement), high resistance or ari open exists in the field circuit. Check for poor conncections between field winding leads and slip ring terminals. If cause for open or high resistance cannot be found, connect ohmmeter directly to slip ring terminals. If correct reading is now- obtained. replace slip rings. If reading is still high or infinite, replace complete rotor assemblv. d. If reading is low. a short exists in the field circuit. Inspect slip rings lo be sure that thev are not bent and touching outer slip ring. Also be sure thai excess solder is not shorting terminals to aft slip ring. If cause for short cannot br found, unsolder field winding leads from slip ring terminals and connect ohmmeler directly lo leads. If correct reading is now obtained, slip rings are shorled and must be replaced. If reading is still low, rolor field windings are shorted, and complete rotor assemblv must be replaced. IMPORTANT: If alternator has output at low speeds, but no output at high speeds, rotor field winding may be shorting or grounding out, because of centrifugal force. Replace rotor, if all other electrical components test good. Stator IMPORTANT: Stator leads MUST BE disconnected from rectifier diodes and diode trio for this test. 1. Test stator for grounds, using an ohmmeter (set on Rxl scale), as follows: a. Connect one lead of ohmmeter to one of thestator leads and the other lead to stator frame. (Figure 8) Be sure that lead makes good contact with frame. b. Meter should indicate no continuity (meter should not move). If continuitv does exist, stator is grounded and must be replaced. a - Testing for Grounds b - Testing for Opens Figure 8. Testing Stator 2. Test for opens in stator, using an ohmmeter (set on Rxl scale), as follows: a. Connect ohmmeter betw-een each pair of stator wind ings (3 different ways). (Figure 8) Either of the 2 leads (coming from each stator windings) mav be used. b. Continuity should be present in all 3 cases (meter should move). If it does not. one or more of the windings are open and stator must be replaced. 3. A short in the stator is difficult to detect without special equipment, because of the low windings resistance. If all other electrical components test out good, and alternator fails to produce rated output, stator probably is shorted and should be replaced. Also, examine stator Tor heal discoloration. as this usually is a sure sign of a short. Rectifier Diodes IMPORTANT: Rectifier diodes MUST BE disconnected from stator and diode trio for this test. 3C-14 - ELECTRICAL SYSTEM 90-95693 1-888 A CAUTION DO NOT use a test instrument with more than a 12-volt source {in the following test), as rectifier diodes may be damaged. 1. Connect one lead of an ohmmeter (set on Rxl scale) to rectifier diode heal sink and the other lead to one of the rectifier diode terminals. (Figure 9) Note the reading. DO NOT connect ohmmeter lead to mounting stud(s). 2. Reverse test leads and again note reading. 3. Meter should indicate a high or infinite resistance (no meter movement) when connected one wav and a low reading when connected the other. If' both readings are high or infinite, diode is open. If both readings are low. diode is shorted. 4. Repeat Steps l-thru-3 for 2 other rectifier diodes in heat sink. Also, test other rectifier diode set in same manner. 3. Replace complete rectifier set. if any of the diodes are shorted or open. 11589 a - Heat Sink c - Do Not Connect Lead to Studs b - Diode Terminal d - Test These 2 Diodes in Same Manner Figure 9. Testing Rectifier Diodes for Shorts or Opens (Negative Rectifier Diode Set Shown) Diode Trio IMPORTANT: Diode trio leads MUST BE disconnected from rectifier diodes and stator leads for this test. DO NOT use a test instrument with more than a 12-volt source (in the following test), as recti fier diodes may be damaged. 1. Connect one lead of an ohmmeter (set on Rxl scale) to diode trio stud and the other lead to one of ihe diode trio leads. (Figure 10) Note ohmmeter reading. 2. Reverse ohmmeter lead.- and again note reading. 3. Meter should indicate a high or infinite reading (no meter movement) when meter is connected one wav and a low reading when meter is connected the other wav. If both readings are high, diode (in diode trio) is open. If both readings are low. diode is shorted. 4. Repeat Steps l-thru-3 between diode trio stud and each of the other 2 leads. 5. Replace diode trio if any of the diodes are shorted or open. 90-95693 485 a - Stud b - Repeat Test between These Leads and Stud Figure 10. Testing Diode Trio for Shorts or Opens Condenser 1. I sing Magneto Analvzer and accompanying instructions, perform the following condenser tests: a. Condenser Capacity Test (must be .5 mfd) b. Condenser Short or Leakage Test c. Condenser Series Resistance Test 2. Replace condenser, if test results are not within specifications. REASSEMBLY 1. Press new rear bearing all-the-way onto rotor shaft (until inner race contacts shoulder) with an arbor press and a bearing driver that contacts inner bearing race only, as shown in Figure 11. Use extreme care to prevent damage lo field winding leads. a - Arbor Press b - Bearing Driver (Must Contact Inner Bearing Race Only) c - Suppct Pulley End of Shaft on Arbor Press Base (DO NOT Support Rotor on Pole Pieces) Figure 11. Installing Rear Bearing on Rotor Shaft ELECTRICAL SYSTEM - 3C-15 IMPORTANT: Be sure to support rotor on end of shaft and not on pole pieces, as pole pieces are only press-fit onto shaft. 2. Insert field winding leads thru passage in slip ring hub. then hand-press slip rings onto shaft while maintaining proper alignment with leadsand passage. Install cap screw, lockwasher and flat washer. Tighten securely. 3. Wrap ends of field winding leads around slip ring terminals and solder with rosin core solder. DO NOT use excessive solder. Also. L)0 NOT use excessive heat, or insulation on field winding lead:: mav be damaged. 4. Press new front bearing into front end frame bearing bore. If necessarv. use a bearing driver that contacts outer race onlv. Install bearing retainer into recess in end frame (with ears outward and aligned with opening), usinga long nose pliers and a punch. I se extreme care to prevent damage to front bearing seal. Be sure that retainer is fullv seated in groove (ears should touch both sides of recess). 5. Press front end frame and bearing assemblv onto rotor shaft (until inner bearing race contacts shoulder) with an arbor press and a bearing driver that fits over shaft and contacts inner bearing race only, as shown in Figure 12. Be sure to support rotor on pole pieces only. 11592 a - Arbor Press b - Bearing Driver (Must Contact Inner Bearing Race Only) c - Support Rotor on Pole Pieces Figure 12. Installing Front End Frame and Bearing Assembly on Rotor Shaft IMPORTANT: DO NOT clamp vise on rotor pole pieces when tightening pulley nut (in next step), or pole pieces may be distorted. 6. Slide tan spacer onto rotor shaft. Install new woodruff key. then install fan. pulley, lockwasher and nut or. shaft. Clamp pullev in a \ise. using protective jaws or an old over-size \ -belt to protect pullev (Figure4), and torcue nut to specifications. Tighten vise only enough to allow tightening of nul. as excessive tightening may distort pullev. Position diode trio in positive rectifier set heat sink. I sing rosin core solder, resolder stator and diode trio leads to rectifier diodes, as shown in Figure 13. I se long-nose pliers to prevent heat damage to diodes. Solder connections as quickly as possible and allow them to cool before removing pliers. Place insulating washers and sleeves on diode trio stud and positive rectifier set stud, as shown in Figure 13. 9. Guide rear end frame onto diode trio and rertifier diode set studs, then install condenser, insulating washers, flat washers, lockwashers and nuts, as shown in Figure 14. Tighten nuts securelv. a - Diode Trio Stud b - Small Insulating Washer and Sleeve c - Positive Rectifier Set Stud d - Large Insulating Washer and Sleeve Figure 13. Insulating Washer and Sleeve Installed a - Self Locking Nut f - Flat Washer b - Flat Washer g - Insulating Washer c - Insulating Washer h - Self-Locking Nuts d - Nut i - Condenser e - Lockwasher Figure 14. Attaching Rear End Frame to Rectifier Diode Sets and Diode Trio 3C-16 - ELECTRICAL SYSTEM 90-95693 1-888 10. Install new rear bearing retainer in recess in rear end frame bearing bore. Lubricate exposed surface of retainer with a small amount of hydraulic brake fluid to ease assembly over the rear bearing. DO .NOT use oil or grease. 11. Position rear end frame and stator assemblv over front end frame and rotor assembly and align scribe marks on each (scribed during disassembly). Hand-press end frames together. then install thru bolts and square nuts. Tighten bolts securely. 12. Place brush set in rear end frame cavity and secure with 2 mounting screws, as shown in Figure 15. Be sure to use outer-most mounting holes, l ighten securelv. 13. Position felt sea! on regulator mounting surface. Connect regulator field lead lo brush terminal (shown in Figure 15). then mount regulator. Tighten securelv. IMPORTANT: Regulator field lead MUST BE con nected as shown in Figure 15, or lead may be dam aged by rotor slip rings during operation. a - Brush Set (Use Outer Mounting Holes) b - Be Sure tc Connect Field Lead as Shown c - Regulator Felt Seal Figure 15. Installing Brush Set and Regulator INSTALLATION I. Position alternator in mounting bracket and install mounting bolt, washers (if used), spacer and nut. Place washers (if used) on each side of spacer. DO NOT tighten nut securelv at this time. a - Black b - Orange (or Red/White) c - Purple (or White) d - Red/Purple (or Red) Figure 16. Wiring Harness Connected to Alternator 2. Fasten alternator brace to alternator with bolt, washers and spacer (if used). DO NOT tighten bolt at this time. 3. Position alternator drive belt on pulleys and adjust tension as explained under "Drive Bell Tension Adjustment". 4. Reconnect wiring harness lo alternator (Figure 16) and negative battery cable to battery. 90-95693 1-888 ELECTRICAL SYSTEM - 3C-17 DELCO ALTERNATOR TORQUE SPECIFICATIONS Fastener Location Lbs. Ft. (N.m) Lbs. In. (N.m) Alternator Brace To Alternator 192 (28) Alternator Brace To Block 30 (41) Alternator To Mounting Bracket 35(48) Alternator Mounting Bracket 30 (41) Brush Holder Securely Diode Trio Securely Pulley Nut 50 (68) Rectifier Bridge Securely Regulator Retaining Screws Securely Retainers (Flame Arrestor) Securely Thru Bolts Securely TOOLS/SEALANTS MERCURY MARINE SPECIAL TOOLS 91-31229A5 Bearing Removal and Installation Kit 91-76032 Magneto Analyzer 91-37241 Universal Puller Plate 91-99750 Volt/Ohmmeter 3C-18 -ELECTRICAL SYSTEM 90-95693 1-888 SPECIFICATIONS Mercury Number (Delco Number) Amp Output (Max.) Rotation No. of Wires 68085 (1102393) 37 Uni-Rotational 1 Wire 69729 (1102496) 37 Bi-Rotational 1 Wire 78477 (1102938 or 1102939) 37 Uni-Rotational 3 Wire 90793 (1103113) 37 Uni-Rotational 3 Wire 90794 (1103114) 37 Bi-Rotational 3 Wire DESCRIPTION Two basic I vpes of Delco internally-regulated alternators are in use on MerCruiser Engines: The 1-wire alternator and the 3-wire alternator. IMPORTANT: Reference to number of wires does not include ground wire. Both the 1-wire and 3-wire alternators are very similar in construction and operation, with the exception of the voltage regulator. Each emplovs a rotor that is supported ir 2 end frames bv bearings and is driven bv a pullev at approximately twice engine speed. The rotor contains a field winding that is encased between 2 multiple finger pole pieces. Both ends of the field winding are connected to 2 insulated slip rings that are mounted on the rotor shaft. Current is supplied to the field winding bv 2 brushes (mounted in the slip ring end frame) which make continuous slipping contact with the slip rings. The current flow through the field winding creates a magnetic field that causes the adjacent fingers of the pole pieces to become alternate north and south poles. A 3-phase stator is mounted directly over the rotor pole pieces and between the2end frames. Il consistsof3 windings wound 120° electrically out-of-phase on the inside of a laminated core. The windings are til connected together on one end while the other ends are connected to a full-wave rectifier bridge. The rectifier bridge contains 6 diodes which are arranged in such a manner thai il allows current to flow from ground, thru the stator and lo the batterv ("BAT") terminal, but not in the opposite direction. \\ hen current is supplied to the rotor field winding (source to be explained later). and the rotor is turned, the movement of the field induces an alternating current into the stator windings. The rectifier bridge then changes this current to direct current which appears at the oattery ("BAT") terminal. A diode trio also is connected to the stator windings and to the rectifier bridge w hich supplies current to the rotor field winding curing operation. \oltage output of the alternator is maintained within prescribed limits for properly charging the batterv by a transistorized voltage regulator that controls the flow of current thru the rotor field circuit. The regulator, which is used on the 1-wire alternator, senses internally within the alternator, while the regulator, that is used on the 3-wire alternator, is equipped with an external sensing circuit that senses near the batterv. This external sensing feature allows the alternator to compensate for any resistance in the output circuit, thereby providing more accurate regulation of the voltage being applied to the battery. The voltage regulator, that is used on the 3-wire alternator, also is equipped with an excitation circuit which is connected to the ignition switch. It provides a small amount of current to the rotor field winding to initiate alternator output when starting. This enables the 3-wire alternator to builc up voltage faster than the 1-wire alternator which relies solely on residual magnetism for initial start-up. Once the alternator is producing output, current for the rotor field winding is supplied solely bv the diode trio. A diode (located in the regulator terminal connector) prevents current from the diode trio from feeding back thrj the excitation circuit and into the ignition system, thus preventing engine run-on after the ignition switch is turned off. Both alternatcrs also are equipped with a fan (mounted on the rotor shaft) which induces air flow thru the alternator to remove the heat created by the rectifier bricge and stator. A capacitor is also utilized to protect the rectifier from high voltages and to suppress radio noise. Current output of the alternator does not require regulation (as does the DC generator), as maximum current output is self-limited by the design of the alternator. As long as the voltage is regulated within prescribed limits, the alternator cannot produce excessive current. A cutout relay in the alternator system also is not required as the rectifier diodes prevent the batterx from discharging back through the stator. The alternator system, that is used with the 1-wire and 3-wire alternators, include the alternator, batterv and the wiring which connects these components. The 3-wire alternator system. in addition to these components, also includes the ignition switch and related wiring. Refer to ' Section 3. Part F for wiring diagram. 90-95693 1-888 ELECTRICAL SYSTEM - 3C-19 PRECAUTIONS The following precautions MUST BE observed when working bilge blower, run blower for at least 5 minutes before on the alternator system. Failure to observe these precautions disconnecting cables. mav result in serious bodily injury and/or damage to the 5. Alwavs disconnect both battery cables from battery before alternator or alternator system. disconnecting anv leads from alternator or other com1. DO NOT attempt to polarize the alternator. ponents in alternator system. 2. DO NOT short across or ground anv of the terminals on the 6. When installing batterv. BE SURE to connect the negative alternator, except as specifically instructed in "Trouble(-) (grounded) batterv cable to negative (-> battery termishooting Tests". nal and the positive (+) battery cable to positive (+) battery 3. NEVER disconnect the alternator output lead or battery terminal. If cables are reversed, damage lo voltage regulacables when the alternator is producing a charge. Make tor and/or alternator diodes will result. sure that all connections in the svstem are tight before 7. If a charger or booster battery is to be used, BE] SI RE to starting the engine. connect it in parallel with existing battery (positive to 4. Before disconnecting batterx cables (or other leads in positive, negative to negative). alternator svstem). be sure that engine compartment is 8. When applving a booster charge lo batterv. be sure to well ventilated and that there are no gasoline vapors disconnect both battery cables from baiterv to prevenl present to prevent the possibility of an explosion and/or a alternator diodes and transistorized voltage regulator from fire should a spark occur. If boat is equipped with a being damaged. PERIODIC MAINTENANCE The following maintenance check should be performec every 50 hours or 60 davs (whichever comes first) in fresh water areas or every 25 hours or 30 davs in salt water areas. Remove all battery cables from battery (before conducting the following check) to prevent accidentally shorting out electrical system. 1. Inspect entire alternator system for corroded or loose connections. 2. Check wiring for fraved or worn insulation. 3. Check alternator drive belt for excessive wear, cracks, fraving and glazed surfaces. Also, check drive belt tension and adjust, if necessary, as explained under "Drive Belt Tension Adjustment" 4. Check alternator mounting bolts for adequate tightness. 5. Inspect slip ring end frame flamearrestor screen for debris and clean, if necessary, using compressed air or a cloth. Screen Ml ST BE clean, or alternator mav overheat. TROUBLESHOOTING TESTS (ALTERNATOR ON ENGINE) l se the following tests in conjunction w ith the "Troubleshooting" in Section 1. Before proceeding with the tests, however, perform the following checks to eliminate possible problem areas. Also observe "Precautions", immediately preceding, to prevent damage to alternator system. 1. If problem isan undercharged battery, check to ensure that undercharged condition has not been caused bv excessive accessory current draw or bv accessories which have accidentally been left on. Also, check that undercharged condition has not been caused by running engine at too low a speed for extended periods of time. 2. Check physical condition and state of charge of battery, as outlined in "Section 3. Part A". Battery MUST BE at least 75% (1.230 specific gravity) of fully charged to obtain valid results in the following tests. 3. Check batterv cable connections and ail other accessible alternator system electrical connections for looseness or corrosion. 4. Check alternator drive belt for excessive wear, cracks, fraving and glazed surfaces and replace if necessary. Also, check drive tension and adjust, if necessary, as outlined under "Drive Belt Tension Adjustment". VOLTAGE REGULATION TEST Perform this test to determine if alternator voltage output is being maintained within prescribed limits for properly charging the batterv. 1. Connect positive (+) lead of a DC voltmeter (set on 0-20 volt scale) to positive ( + ) batterv terminal and negative (-) lead to negative (-) terminal. (Figure 1) IMPORTANT: Battery MUST BE fully charged (1.260 specific gravity or above) to obtain proper voltage reading in next step. If necessary, charge battery with a battery charger or allow engine to run a sufficient length of time to fully charge battery before taking reading. All accessories MUST BE turned off during this test. 3C-20 - ELECTRICAL SYSTEM 90-95693 1-888 2. Start engine and run at fast idle until engine reaches 4. If reading is high, stop engine and proceed as follows: normal operating temperature. Adjust engine speed to a. On 3-wire alternator svstem onlv: Test alternator 1500-2000 RPM and observe voltmeter for highesl reading. system sensing circuit, as explained under "Alternator Reading should be between 13.9 and 14.7. Svstem Circuitrv Test", following. b. Remove alternator, disassemble and test the following IMPORTANTrOn 3-wire alternator system only: If reading is normal, but frequent replacement of light bulbs at dash is necessary (indicating high voltage in alternator system), test alternator output circuit for excessive resistance, as explained under "Alternator System Circuitry Test", following. components, as explained under "Alternator Repair". 1) Test upper brush lead clip and voltage regulator for a grounded condition. If grounded, check for a missing or damaged insulator on upper brush lead clip insulated screw . If insulator is good, replace voltage regulator. 2) Test rotor for a shorted field winding. If shorted, replace both rotor and regulator. c. If cause for overcharging condition cannot be found, 3. If reading is low. stop engine and perform "Alternator replace voltage regulator. Current Output rest", following, to locate source of d. Reassemble alternator and reinstall as outlined under problem. Alternator Repair . a - Red Battery Cable d - Ammeter (50 Amp Scale) b - Ground Cable e - Voltmeter (0-20 Volts) c - Output Wire - Orange (Red/White) Figure 1. Alternator Voltage Regulator Test and Current Output Test 90-95693 485 ELECTRICAL. SYSTEM - 3C-21 CURRENT OUTPUT TEST Perform this test to determine if alternator is capable of producing rated current output. 1. Disconnect batterv cables from battery. 2. Disconnect orange (red-white) engine wiring harness lead from alternator battery ("BAT") terminal and connect a DC ammeter (with 0-50 amp scale) in series between lead and batterv terminal. (Figure 1) Connect positive <+) side of ammeter toward battery terminal. 3. Reconnect battery cables. 4. Remove coil hi-tension lead from distributor cap tower and ground it to block. Turn on all accessories and crank engine over with starter motor for 15-20 seconds. 5. Turn off accessories and reinstall coil hi-tension lead. Start engine and quickly adjust engine speed to 1500-2000 RPM and note ammeter reading. Reading should be at ieast 25 amps (for 1-wire alternator systems) or30amps (for 3-wire alternator systems). 6. If no output or low output is indicated, stop engine and test alternator output circuit and ground circuit, as explained under "Alternator System Circuitry Test", following. On 3-wire alternator systems, also test alternator excitation circuit. If circuits test out good, proceed as follows: a On alternators with a removable slip ring end frame flame arrc-lor srreen (Figure 2), remove screws and lockwashers and remove screen. a - Slip Ring End Frame Flame Arrestor Screen b - Attaching Screws and Lockwashers Figure 2. Alternator with Removable Slip Ring End Frame Flame Arrestor Screen b. On alternators with non-removable slip ring end frame flame arrestor screen (Figure 3). remove slip ring end frame flame arrestor cover and screen assembly, as follows: 1) Disconnect battery cables from battery. 2) Disconnect test ammeter from battery ("BAT") terminal on alternator. 3) On 3-wire alternators only, remove nuts and bracket which secure regulator terminal connector (Figure 3) to alternator and remove connector. 4) Reniove4alternator thru bolts and ground lead clip (Figure 3). then, while holding slip ring end frame in position, remove slip ring end frame flame arrestor cover and screen assembly. Reinstall thru bolts and ground lead clip. Tighten screws securely. a - Slip Ring End Frame Flame Arrestor Cover and Screen Assembly b - Thru Bolts (One Hidden) c - Ground Lead Clip d - Regulator Terminal Connector Figure 3. Alternator with Non-Removable Slip Ring End Frame Flame Arrestor Screen 5) Reconnect ammeter, regulator terminal connector and batterv cables. Be sure that engine compartment is well ventilated and that there are no gasoline vapors present (during the next test) to prevent the possibility of an explosion and/ora fire, should a spark occur. If boat is equipped with a bilge blower, run blower for at leasts minutes before performing test. c. Repeat Steps 4 and 5. Vi hile observing ammeter, momentarily ground rotor field wind by inserting a screwdriver into test hole (Figure 4) and grounding tab to slip ring end frame. Tab is within %" (19mm) of slip ring end frame surface. DO NOT insert screwdriver deeper than 1" (25mm) into end frame, or damage to rotor may result. 3C-22 - ELECTRICAL SYSTEM 90-95693 1-888 a - Test Hole b-Tab c - Slip Ring End Frame d - Ground Tab to End Frame with Screwdriver Figure 4. Grounding Rotor Field Winding d. If proper output is now obtained, remove alternator, disassemble and replace voltage regulator, as explained under "Alternator Repair", following. e. If output is slill low, remove alternator, disassemble and test rotor, stator. diode trio and rectifier bridge, as explained under "Alternator Repair", following. f. Reassemble alternator and reinstall as outlined under "Alternator Repair". CIRCUITRY TEST Perform the following test to determine if all of the circuits between the alternator and the other components within the svstem are in good condition. Output and Ground Circuit IMPORTANT: The following test cannot be used on boats equipped with battery isolators. 1. Disconnect battery cables from batterv. 2. Disconnect orange (red-white) engine wiring harness lead from alternator battery ("BAT") terminal and connect a DC ammeter (with 0-50 amp scale) in series between lead and battery terminal. (Figure 5) Connec: positive (+) side of ammeter toward batterv terminal. 3. Reconnect battery cables. 4. Connect positive (+) lead of a DC voltmeter (set on 0-20 volt scale) to alternator battery terminal and negative (-) lead to alternator ground terminal. (Test No. 1 in Figure 5) 5. Wiggle engine and instrumentation wiring harness while observing voltmeter. Meter should indicate approximate battery voltage and should not vary. If no reading is obtained, or if reading varies, check alternator output circuit for loose or dirtv connections or for damaged wiring. (Refer to appropriate wiringdiagram in "Section 3. Part F") 6. Disconnect negative voltmeter lead from alternator ground terminal and reconnect il lo positive (+) battery terminal. (Test No. 2 in Figure 5) Set voltmeter on 0-3 volt scale. 7. Start engine and adjust speed to 1500-2000 RPM. Turn on sufficient accessory load to induce a 10 amp charge from alternator (indicated on test ammeter). 8. Note voltmeter reading. Reading should not exceed 1.0 volt. |Reading may be slightly higher on boats with wiring harnesses over 40 ft. (12m).| If reading is high, excessive resistance exists in output circuit. If so. -top engine and clean and tighten all output circuit connections. 9. Test ground circuit of alternator for excessive resistance by connecting positive voltmeter lead to negative (-) battery terminal and negative lead to alternator ground terminal. (Test No.3 in Figure 5) Repeat Step 7 and note voltmeter reading. Reading should not exceed 0.1 volt. If reading is high. STOP ENGINE and clean and tighten all ground circuit connections. 10. Disconnect battery cables, remove meters and reconnect orange (red-white) engine wiring harness lead. Then, as a last step, reconnect batterv cables. 90-95693 485 ELECTRICAL. SYSTEM - 3C-23 a - Output Wire - Orange (Red/White) e - Ground Cable b - Excitation Wire - Purple (White) f - Voltmeter (0-20 Volts) c - Sensing Wire - Red/Purple (Red) g - Ammeter (50 Amp Scale) d - Red Battery Cable Figure 5. Alternator Output Circuit and Ground Test Excitation Circuit (3-Wire Alternator Only) 4. Vi iggle portion of engine wiring harness, thai contains purple (white) exc itation lead, while observing voltmeter. 1. Remove nuts and bracket, which secure regulator terminal Meter should indicate at least 5 volts and should not vary. connector (Figure 3) to alternator, and remove connector. 5. If no reading is obtained, or if reading varies, turn ignition 2. Using a pin or similar device, connect positive (+) lead of a switch to ' Off and disconnect purple (white) engine DC voltmeter (set on 0-20 volt scale) to terminal in con-wiring harness lead from regulator terminal connector al nector to which purple (white) wire is attached. Conneci bullet connector. negative (-) voltmeter lead to alternator ground terminal. 6. Disconnect positive ( + ) voltmeter lead from regulator ter( Figure 12) minal connector and reconnect to purple (while) engine 3. Turn ignition switch to "On" position. wiring harness lead (excitation lead). (Figure A) 3C-24 - ELECTRICAL SYSTEM 90-95693 1-888 b - Excitation Wire - Purple (White) c - Sensing Wire Red/Purple (Red) d - Voltmeter (0-20 Volts) e - Test Lead and Pin Figure 6. Alternator Excitation Circuit Test DO NOT allow end of purple (white) engine wiring harness lead to contact engine (in next step), or an electrical short will occur. 7. Repeat Steps 3 and 4. If proper reading is now obtained, replace regulator terminal connector. If no reading is obtained, or if reading varies, check purple (white) engine wiring harness lead for loose or dirty connections or damaged wiring. 8. Reinstall regulator terminal connector. Be sure toinsulate bullet connection(s) with heat shrink tubing or at least 4 layers of electrical tape. Sensing Circuit (3-Wire Alternator Only) 1. Remove r.uts and bracket, which secure regulator terminal connector (Figure 3) to alternator, and remove connector. 2. Using a pin or similar device, connect positive (+) lead of a DC voltmeter (set on 0-20 volt scale) to terminal in connector to which red/purple (red) lead is attached. Connect negative voltmeter lead to alternator ground terminal. (Figure 7j 3. With ignition switch in the "Off' position, wiggle portion of engine wiring harness, that contains red/purple (red) sensing lead, while observing voltmeter. Voltmeter should indicate battery voltage and should not vary. If no reading is obtained, or if reading varies, check red/purple (red) sensing lead for loose or dirty connections or damaged wiring. 4. Remove meter and reinstall regulator terminal connector. a - Output Wire - Orange (Red/White) b - Excitation Wire - Purple (White) c - Sensing Wire - Red/Purple (Red) d - Voltmeter (0-20 Volts) e - Pin and Test Lead Figure 7. Alternator Sensing Circuit Test 90-95693 485 ELECTRICAL. SYSTEM - 3C-25 ATERNATOR REPAIR REMOVAL washer(s) and spacer (if used). 4. Loosen alternator mounting bolt, then pivot alternator 1. Disconnect all batterv cables from battery. inward and remove alternator drive belt. 2. Disconnect engine wiring harness from alternator. 5. Remove alternator mounting bolt, washer(s) (if used), 3. Remove alternator brace to alternator attaching screw. spacer and nut and remove alternator. §1 - Screw (7) 2 - Lockwasher (7) §3 - Flame Arestor Screen 4 - Bolt 5 - Ground Lead Clip §6 - Flame Arestor Cover 7 - Screw 8 - Insulator §9 - Rubber Washer 10 - Bearing 11 - End Frame 12 - Rectifier Bridge *13 - Spring Washer 14 - Screw ard Lockwasher Assembly 15 - Nut *16 - Jumper Wire 17 - Voltage Regulator 18 - Shorting Clip '19 - Nut 20 - Brush Holder Assembly 21 - Brush Springs "22 - Spring Washer 23 - Screw (Ground) 24 - Screws (Insulated) 25 - Diode Trio 12339 26 - Nut (3) *27-Spring Washer (3) 28 - Screw 29 - Mounting Bracket 30 - Capacitor 31 - Screw 32 - Stator §33 - Rubber Plug 34 - Rotor "35 - Rotor Shaft Inner Collar [11/32" (8.7mm) Thick] §36 - Screw and Lockwasher Assembly *37 - Spring Washer (3) §38 - Bearing Retainer Plate §39 - Flame Arrestor Screen 40 - Bearing 41 - Grease Slinger Washer 42 - End Frame 43 - Rotor Shaft Outer Collar [7/32" (5.6mm) Thick] 44 - Fan 45 - Pulley 46 - Lockwasher 47 - Nut * May not be used on some alternators. § Part(s) must be installed for alternator to be property flame arrested. Figure 1.1-Wire Alternator Parts View 90-95693 1-888 3C-26 - ELECTRICAL SYSTEM 1 - Bolt (4) 2 - Ground Lead Clip §3 - Flame Arrestor Cover 4 - Nut (2) 5 - Bracket 6 - Regulator Terminal Connector 7 - Screw 8 - Insulator §9 - Rubber Washer 10 - Bearing 11 - End Frame 12 - Rectifier Bridge 13 - Screw and Washer Assembly 14 - Nut 15 - Voltage Regulator §16 - Rubber Boot 17 - Brush Holder Assembly 18 - Brush Springs 19 - Screw (Ground) 20 - Diode Trio 21 - Diode Trio 22-Nuts (3) 23 - Screw 24 - Bracket 25 - Capacitor 26 - Screw 27 - Stator §28 - Rubber Plug 29 - Rotor §30 - Screw and Lockwasher Assembly (3) "31 - Spring Washer (3) §32 - Bearing Retainer Plate §33 - Flame Arrestor Screen 34 - Bearing 35 - Grease Slinger Washer 36 - End Frame 37 - Rotor Shaft Collar 38 - Fan 39 - Pulley 40 - Lockwasher 41 - Nut * May not be used on some alternators. § Part(s) must be installed for alternators to be properly flame arrested. Figure 2. 3-Wire Alternator Parts View 90-95693 485 ELECTRICAL. SYSTEM - 3C-27 IMPORTANT: The following instructions are for complete disassembly and overhaul of alternator. In many cases, however, complete alternator disassembly is not required and, in those cases, it is necessary to perform only the operations which are required to repair or replace the faulty part. DISASSEMBLY 1. Mount alternator in a vise by clamping on mounting flange. 2. Scribe a mark on slip ring end frame and drive end frame to ensure proper reassembly later. 3. Remove 4 alternator thru bolts and ground lead clip and separate slip ring end frame and stator assembly from drive end frame and rotor assembly, being careful not to lose brush springs. If necessary, insert a screwdriver between stator and drive end frame and pry assemblies apart. DO NOT insert screwdriver so far that it contacts stator windings. IMPORTANT: Brushes may drop onto rotor shaft and become contaminated with bearing lubricant. Be sure to clean brushes prior to installing with a non-toxic cleaner (such as trichlorethylene) and a soft dry cloth. If lubricant is not removed, brushes will not make good contact with slip rings, resulting in poor alternator performance. 4. Place a piece of tape over bearing surface on rotor shaft to protect it from getting nicked or scratched. If slip ring end frame bearing is not to be replaced, also place a piece of tape over bearing opening to prevent dirt or other foreign material from entering. 5. On 3-wire alternator onlv. remove 2 nuts and bracket, which secure regulator terminal connector to slip ring end frame, and remove connector. 6. Remove flame arrestor cover from slip ring end frame. IMPORTANT: If troubleshooting an overcharging condition, rotor can be tested for a short, and upper brush lead and regulator can be tested for grounds with alternator disassembled to this point. Refer to "Component Testing", following. 7. Remove diode trio and stator lead attaching nuts (and spring washers, if so equipped) and separate stator from slip ring end frame. Remove rubber plug from groove on outside edge of stator frame. 8. Remove insulated screw (and spring washer, if so equipped), which attach diode trio to brush holder assemblv, and remove diode trio. 9. Remove capacitor mounting bracket attaching screw- and capacitor lead attaching screw and remove capacitor. IMPORTANT: With alternator disassembled to this point, stator, rotor, rectifier bridge, diode trio, regulator terminal connector and capacitor can be tested, as explained under "Component Testing", following. 10. Remove screw, washer and nut. which secure rectifier bridge to slip ring end frame, and remove rectifier bridge. Also remove battery terminal screw. insulating washer and sponge rubber washer from end frame. 11. Remove remaining insulated screw and ground screw (and spring washers, if so equipped). which secure brush holder assemblv and voltage regulator to slip ring end frame, and remove brush holder assembly and regulator. 12. On 1-wire alternators so equipped, remove nut that secures jumper wire to voltage regulator and remove wire. 3C-28 - ELECTRICAL SYSTEM 13. If slip ring end frame bearing requires replacement, press bearing out of end frame (from outside inward), using a suitable dri\er and an arbor press. Bearing MUST BE replaced, if grease supply is exhausted. Make no attempt to re-lubricate old bearing. 14. Remove pulley attaching nut from rotor shaft by turning nut in couterclockwise direction with a box end wrench, while holding rotor shaft with an alien wrench, as shown in Figure 3. a - Allen Wrench b - Box End Wrench Figure 3. Removing Pulley Attaching Nut 15. Remove washer, pullev, fan and collar from rotor shaft. Now remove rotor and inner collar (if so equipped) from drive end frame. 16. Remove drive end frame bearing retainer plate attaching screws (and spring washers, if so equipped), then remove retainer plate and flame arrestor screen from end frame. 17. If drive end frame bearing requires replacement, press bearing and grease slinger washer out of erd frame, using a suitable driver and an arbor press. CLEANING and INSPECTION IMPORTANT: DO NOT clean electrical components with solvent (in next step), as components may be damaged. 1. Clean all electrical components with a clean, soft cloth ONLV Clean non-electrical components (except slip ring end frame bearing) w ith solvent and dry with compressed air. 2. Clean brushes with a non-toxic solvent (such as triclorethvlene) and a soft cloth. IMPORTANT: Rotor MUST BE spun while cleaning slip rings (in next step). Cleaning the slip rings by hand, without spinning the rotor, may result in flat spots on the slip rings and cause brush noise and excessive slip ring and brush wear. 3. Clean rotor slip rings with 400 grain (or finer) polishing cloth while spinning rotor in a lathe. Blow off dust with compressed air. If slip rings are rough or out-of round |.002" (0.05mm) maximum], true slip rings in a lathe, removing onlv enough material to make rings smooth and round. Finish with 400 grain or finer polishing cloth. If slip 90-95693 1-888 rings are damaged beyond repair, rotor MUST BE replaced. 4. Inspect the following parts for wear and damage a. Brush and holder assembly: Inspect for cracked porcelain casing, damaged brush leads, poor brush lead connections, damaged brush lead clips or worn brushes. Brush holder assembly MUST BE replaced, if brushes are less than V\" (6mm) long. b. Brush holder assembly and voltage regulator insulated attaching screws: Inspect for missing or damage insulators. IMPORTANT: If insulator on insulated screws is missing or damaged, no output or uncontrolled alternator output will result during operation. c. Brush springs: Inspect for corrosion or distortion and check for adequate spring tension. d. Voltage regulator: Inspect for cracked porcelain case. e. Rotor: Inspect for damaged threads, scuffed pole piece fingers or damaged bearing surfaces. Rotor MUST BE replaced, if pole pieces are scuffed or bearing surfaces are damaged. f. Drive end frame bearing: Inspect for roughness, pitting, flat spots, discoloration (due to overheating) or excessive side or end plav. Hold inner race ol bearing while turning outer race. Bearing should turn freely without binding or evidence of rough spots. g. Drive end frame bearing retainer: Inspect seal for excessive wear, cracks, roughness or other signs of deterioration. h. Slip ring end frame bearing: Inspect for flat spots, pitting or discoloration due to overheating. Inspect bearing seal for cracks, flat spots, roughness or other signs of deterioration. Entire bearing MUST BE replaced. if seal is damaged. Also check bearing for adequate lubrication. If grease supply is exhausted, bearing MUST BE replaced. Make no attempt to re-lubricate bearing. i. End frames:lnspec.t for cracks, distortion, stripped threads or wear in bearing bore due to a spur, bearing. End frame(s) MUST BE replaced, if bearing(s) have spun. j. Slator: Inspect for damaged insulation or wires. Also, inspect insulation for heat discoloration, as this usuallv is a sign of a shorted or grounded winding, k. Fan: Inspect for cracked or bent fins or broken welds on bi-rotational fans. 1. Pulley: Inspect pulley sheaves for rotational trueness. undercut surfaces (from excessive wear), nicks, pitting or corrosion. Repair surfaces, if possible, with a fine file and a wire brush or replace pulley, if beyond repair. Drive surfaces MUST BE perfectly true and smooth, or drive belt wear will be greatly accelerated. COMPONENT TESTING Upper Brush Lead Clip and Regulator Ground Test IMPORTANT: The following test need be performed only if an overcharging condition exists. 1. Connect one lead of an ohmmeter (set on Rxl scale) to upper brush lead clip and the other lead to slip ring end frame, as shown iri Figure 4. Note ohmmeter reading. 90-95693 485 2. Reverse ohmmeter leads and again note reading. 3. If both readings are zero, either upper brush lead clip is grounded or voltage regulator is defective. A grounded brush lead clip can result from a damaged or missing insulator or. insulated screw that secures upper brush lead clip. Remove screw and inspect insulator. If satisfactory, replace voltage regulator. IMPORTANT: Some older alternators may have an insulated screw with a separate insulating sleeve and washer instead of a one-piece insulator. On these alternators, be sure that both insulating sleeve and washer are not missing or damaged. a - Upper Brush Lead Clip 6 - Insulated Screw Figure 4. Testing for Grounded Brush Lead Clip or Defective Regulator Rotor 1. Test rotor field circuit for grounds, usingan ohmmeler (set on Rxl scale), as follows: a. Connect one lead of ohmmeter to either slip ring and the other lead to rotor shaft. (Figure 5) b. Meter should indicate no continuitv (meter should not move). c. If continuity exists, rotor field is grounded and rotor must be replaced. 2. Test rotor field for shorts or opens, usingan ohmmeter (set on Rxl scale), as follows: a. Connect one ohmmeter lead to each slip ring. (Figure 5) b. Ohmmeter reading should be 2.55 to 2.95 ohms with rotor at room temperature |60° -80° F (16° -27° C)]. c. If reading is low. rotor field is shorted. If reading is high or infinite (no meter movement). high resistance or an open exists in field. In either case, rotor must be replaced. IMPORTANT: If alternator has output at low speed but no output at high speed, rotor field winding may be shorting or grounding out due to centrifugal force. Replace rotor if this situation exists, and if all other electrical components test good. ELECTRICAL. SYSTEM - 3C-29 12341 a - Test for Grounds b - Test for Shorts or Opens Figure 5. Testing Rotor Field Circuit Stator IMPORTANT: Stator leads MUST BE disconnected from rectifier bridge for this test. Test stator for grounds, using an ohmmeter (set on Rxl scale), as follows: a. Connect one lead of ohmmeter to one of the stator leads and the other lead to stator frame. (Figure 6) Be sure that leads make good contact with stator frame. b. Meter should indicate no continuity (meter should not move). If continuity does exist, stator is grounded and must be replaced. 12342 a - Testing for Grounds b - Testing for Opens Figure 6. Testing Stator Windings 3C-30 - ELECTRICAL SYSTEM 2. Test for opens in stator. using an ohmmeter (set on Rxl scale) as follows: a. Connect ohmmeter between junction clip and each of the stator winding lead terminals (3 different ways). (Figure 6) b. Continuity should exist in all 3 cases (meter should move) If it does not. a w inding is open and stator must be replaced. 3. A short in the stator is difficult to detect without special laboratory equipment due to the low resistance of the windings. If all other electrical components test out good, and alternator fails to produce rated output but will produce a minimum of 5 amps output, stator probably is shorted and should be replaced. Rectifier Bridge IMPORTANT: Rectifier bridge can be tested while installed in end frame. Stator and diode trio, how ever, MUST BE removed. DO NOT use a test instrument with more than a 12-volt source (in the following test), as rectifier bridge may be damaged. 1. Connect one lead of an ohmmeter (set cn Rxl scale) to negative (grounded) heat sink and the other lead to one of the negativ e (-) heat sink diode leads. (Figure 7) IMPORTANT: DO NOT connect ohmmeter test lead directly to rectifier bridge terminal studs, as diode leads may not be making good contact with studs with terminal nuts removed. a - Negative [Grounded) Heat Sink b - Negative ;-) Heat Sink Diode Lead c - DO NOT Connect Test Lead to Stud d - Repeat Same Test for These 2 Negative Heat Sink Diode Leads Figure 7. Testing Negative Heat Sink Diodes 90-95693 1-888 2. Reverse test leads and again note reading. 3. Meter should indicate a high or infinite resistance (no meter movement), when connected one way, and a low reading when connected the other. If both readings are high or infinite, ciode is open. If both readings are low. diode is shorted. a - Positive (Insulated) Heat Sink b - Positive (+) Heat Sink Diode Lead c - Repeat Test for ~hese 2 Positive Heat Sink Diode Leads Figure 8. Testing Positive Heat Sink Diodes 4. Repeat same test between negative (-) heat sink and 2 other negative heat sink diode leads. (Figure8) Also repeat test between positive (insulated) heat sink and each of the 3 positive (+) heat sink diode leads, as shown in Figure 8. 5. Replace complete rectifier bridge, if any one of the diodes is shorted or open. Diode Trio IMPORTANT: Diode trio MUST BE removed from slip ring end frame for this test. DO NOT use a test instrument with more than a 12-volt source (in the following test), as recti fier diodes may be damage. 1. Connect one lead of an ohmmeter (set on Rxl scale) to long connector and the other lead to one of the 3 short connectors. (Figure 9) Note ohmmeter reading. 2. Reverse ohmmeter leads and again note reading. 3. Meter should indicate a high or infinite reading, when meter is connected one way, and a low reading when meter is connected the other way. If both readings are high or infinite, diode (in diode trio) is open. If both readings are low. diode is shorted. 4. Repeat same test between long connector and other 2 short connectors. 5. Replace diode trio if ANY of the diodes (in diode trio) are shorted or open. 90-95693 485 b - Short Connector c - Repeat Test between Long Connector and These 2 Short Connectors Figure 9. Testing Diode Trio Regulator Terminal Connector (3-Wire Alternator Only) 1. Check excitation lead diode in regulator terminal connector for short- or opens by connecting one lead of an ohmmeter (set on Rxl scale) to white lead bullet connector and othe- lead to corresponding terminal in connector. (Figure 10) Note ohmmeler reading. 2. Reverse ohmmeter leads and again, note reading. 3. Meter should indicate a high or infinite reading (no meter movement), when meter is connected one wav. and a low reading when meter is connected the other way. If both readings are high or infinite, diode is open. 11 both readings are low. diode is shorted. 4. If diode is shorted or open, terminal connector Ml ST BE replaced. a - Purple (White) b - Purple (White) Terminal Figure 10. Testing Regulator Terminal Connector Diode ELECTRICAL. SYSTEM - 3C-31 IMPORTANT: If diode in terminal connector is shorted, engine will continue to run after ignition has been turned off. Capacitor 1. Using Magneto Analyzer and accompanying instructions, perform the following capacitor (condenser) tests: a. Capacitor capacity test (must be .5 rnfd). b. Capacitor short or leakage test. c. Capacitor series resistance test. 2. Replace capacitor, if test results are not w ithin specifications. REASSEMBLY (Refer to Figure 1 or 2) All parts, that are marked with the symbol (§)in Figures 1 and 2 MUST BE reinstalled for alter nator to be properly flame-arrested. 1. Fill drive end frame bearing one-quarter full with Ball Bearing Lubricant (Delco Part No. 1948791). DO NOT over-fill, as this may cause bearing to overheat. 2. Place grease slinger washer into recess in drive end frame bearing bore, then press bearing into end frame (with open end upward), using a bearing driver that contacts outer bearing race onlv. 3. Install flame arrestor screen (if so equipped) in drive end frame, then install retainer plate and secure with 3 screws (and spring washers, if so equipped). Tighten screws securely. Shape edges of flame arrestor screen to fit snugly against inside contour of end frame. Flame arrestor screen MUST fit snugly against inside contour of end frame or flame arresting property of screen will be lost. 4. If not already done, clean rotor slip rings as explained under "Cleaning and Inspection", preceding. 5. If so equipped, install 11/32" (9mm) thick collar on rotor shaft, then install rotor in drive end frame. Place 7/32" (6mm) collar, fan. pulley and lockwasher on shaft and secure w ith nut. Torque nut to specifications while nolding rotor shaft with an alien wrench. 6. Press new bearing into slip ring end frame with a flat plate or other suitable tool until bearing is flush with outside surface of end frame. Support inside of end frame around bearing bore with a suitable tool to prevent distortion. Use extreme care to prevent bearing misalignment or otherwise placing undue stress on the bearing. IMPORTANT: Slip ring end frame bearing MUST BE replaced, if grease supply is exhausted. Make no attempt to re-lubricate bearing. Also, DO NOT lubricate new bearing, as bearing is lubricated at the factory, and additional lubricant will ooze out and get on slip rings when alternator is reassembled. 3C-32 - ELECTRICAL SYSTEM 7. Place rectifier bridge in position in slip ring end frame and secure with battery ("BAT") terminal screw , insulator and nut on one end and screw (and spring washer if so equipped) on the other. On alternators so equipped, also install rectifier bridge to regulator jumper w ire under rectifier bridge attaching nut. as shown in Figure 11. Tighten attaching nut and attaching screw securely. 8. Slide condenser into mounting bracket, then install condenser and mounting bracket assemblv i:i slip ring end frame and connect lead to rectifier bridge. Tighten capacitor attaching screws securely. 9. Install shorting clip (on 1-wire alternators) or sponge rubber boot (on 3-wire alternator) over voltage regulator terminals and place regulator in position in slip ring end frame. IMPORTANT: Before installing brushes in brush holder (in next step), clean brushes with a non-toxic cleaner (such as triclorethylene) to remove any residue that may exists. If residue is not removed, brushes may not make good contact with slip rings, which will result in poor alternator performance. 10. Insert brush springs and brushes into brush holder and hold tlieni in place by inserting a toothpick or piece of wire thru holes ,n brush holder. Place brush holder assembly in position on top of regulator with toothpick or wire protruding thru hole in slip ring end frame. (Figure 1 1) 11. Place diode trio in position on rectifier bridge terminals and center diode trio connector over attaching hole in brush holder assembly. 12. Secure diode trio connector, brush holder assemblv and voltage regulator with 2 insulated screws and ground screw (and 3 spring washers, if so equipped), as shown in Figure 11. Tighten screws securely. a - Rectifier Bridge Attaching Nut b - Rectifier Bridge to Regulator Jumper Wire (if so Equipped) c - Regulatcr Terminal Nut d - Toothpick or Wire Retaining Brushes e - Insulated Screws f - Ground Screw Figure 11. Voltage Regulator and Brush Holder Assembly Installed (Alternator with Jumper Wire Shown) 90-95693 1-888 IMPORTANT: Insulated screws (used on most alternators) have a one piece insulator permanently attached to screw body. Some alternators, however, may have insulated screws with only an insulating sleeve over screw body, and a separate insulating washer also is required. Install screw and insulating washer as shown in Figure 12. Two insulated screws and ground screw MUST BE installed as shown in Figure 11 and 12. If ground screw and either of the insulated screws are reversed (or if insulating washers are missing), a ground will result, causing no output or uncontrolled output. 13. On alternators so equipped, connect jumper wire (installed in Step 7) to terminal on regulator and secure with nut. (F'igure 11) Tighten nut securely. a - Insulated Screws b - Insulating Sleeve (Attached to Screw) c - Insulating Washer d - Install Diode Trio Connector under Insulating Washer e - Ground Screw Figure 12. Installing Insulated Screws with 2-Piece Insulators 14. Install rubber plug into groove on outside edge of laminated core stator. as shown in Figure 13. Position stator in slip ring end frame with stator leads over rectifier bridge terminals. Install 3 stator lead attaching nuts (and spring washers, if so equipped). Tighten nuts securely. Rotate slight I v. if necessarv. to align 4 grooves in stator frame with thru bolt holes in end frame. 15. Remove tape that was placed over slip ring end frame bearing and rotor shaft bearing surface during disassembly. Clean bearing surface on rotor shaft to remove any residue, then align scribed marks on end frames (scribed during disassembly) and assembly alternator. DO NOT install thru bolts at this time. a - Rubber Plug Figure 13. Rubber Plug Installed in Stator Laminated Core 16. Remove toothpick or wire from brush holder (thru hole in slip ring end frame) to allow brushes to contact slip rings. 17. Install sponge rubber washer over battery ("BAT") terminal screw insulator. Place flame arrestor cover over slip ring end frame and install 4 thru bolts and ground clip. Tighten bolts securely. 18. On alternators with a removable slip ring end frame flame arrestor screen, reinstall screen (if removed) and secure with 7 screws and lockwashers. Tighten securely. ALL 7 slip ring end frame flame arrestor screen attaching screws MUST BE installed, or altenator will not be properly flame-arrested. 19. On 3-wire alternator onlv: Plug regulator terminal connector ir.to slip ring end frame and secure with attaching bracket and 2 nuts. Tighten nuts securely. INSTALLATION 1. Position alternator in mounting bracket and install mounting bolt, washers (if used), spacer and nut. Place washers (if used) on each side of spacer. DO NOT tighten nut at this time. 2. Fasten alternator brace to alternator with bolt, washer and spacer (if used). DO NOT tighten at this time. 3. Place alternator drive belt on pulleys and adjust tension as explained under "Drive Belt Tension Adjustment". DO NOT use an open flame when installing heat shrink tubing (in next step) to prevent the possibility of an explosion and/or a fire. 4. Reconnect wiring harness to alternator. On 3-wire alternators, insulate red/purple (red) lead and purple (white) lead bullet connections with heat shrink tubing or at least 4 layers of electrical tape. 5. Reconnect batterv cables to batterv. 90-95693 485 ELECTRICAL. SYSTEM - 3C-33 MANDO ALTERNATOR TORQUE SPECIFICATIONS Fastener Location Lbs. Ft. (N.m) Lbs. In. (N.m) Alternator Brace To Alternator 192 (28) Alternator Brace To Block 30 (41) Alternator To Mounting Bracket 35 (48) Alternator Mounting Bracket 30 (41) Brush Retaining Screws Securely Pulley Nut 50 (68) Rectifier Heat Sinks Securely Regulator Retaining Screws Securely Thru Bolts Securely TOOLS/SEALANTS MERCURY MARINE SPECIAL TOOLS 91-31229A5 3earing Removal and Installation Kit 91-76032 Magneto Analyzer 91-37241 Universal Puller Plate 91-99750 Volt/Ohmmeter 3C-34 - ELECTRICAL SYSTEM 90-95693 1-888 SPECIFICATIONS Mercury Number (Mando Number) Amp Output (Max.) Rotation 98555 (AR150AA) 55 Uni-Directional DESCRIPTION The alternator svstem. used on engines with Mando Alternators. consists of the alternator, batterv. the ignition switch and the wiring which connects these components. Refer to "Section 3 Part F for wiring diagrams. The alternator emplovs a rotor, which is supported in 2 end frames by ball bearings, and is driven (via a pulley) at approximated twice engine speed. The rotor contains a field winding that is enclosed between 2 multiple-finger pole pieces. The ends of the field winding are connected to 2 brushes (mounted in the rear end frame) which make continuous sliding (or slipping) contact with the slip rings. The current (flowing through the field winding) creates a magnetic field that causes the adjacent fingers of the pole pieces to become alternate north and south magnetic poles. A 3-phase stator is mounted directIv over t he rotor pole pieces and between the 2 end frames. It consists of 3 windings wound 120° electricallv out-of-phase on the inside of a laminated core. The windings are all connected together on one end, while the other ends are connected to a full-wave rectifier bridge. The rectifier bridge contains 6 diodes which are arranged so that current flows from ground, thru the stator and to the output terminal, but not in the opposite direction. When current is supplied to the rotor field winding, and the rotor is turned, the movement of the magnetic fields created induces an alternating current into the stator windings. The rectifier bricge then changes this alternating current to direct current which appears at the output terminal. A diode trio also is connected to the stator windings to supply current to the regulator and the rotor field during operation. Voltage output of the alternator is controlled by regulating the current supplied to the rotor field. This is accomplished by a transistorized voltage regulator that senses the voltage at the battery and regulates the field current to maintain alternator voltage within prescribed limits for properly charging the battery. Current output of the alternator does not require regulation. as maximum current output is self-limited by the design of the alternator. As long as the voltage is regulated within the prescribed limits, the alternator cannot produce excessive current. A cutout relay in the voltage regulator also is not required, as the the rectifier diodes (which allow current to flow in one direction only) prevent the battery from discharging back through the stator. Due to the lack of residual magnetism in the rotor pole pieces, a small amount of current must be supplied tc the rotor field to initially start the alternator charging. This is accomplished by means of an excitation circuit in the regulator which is connected to the ignition switch. Once the alternator begins to produce output, field current is supplied solely by the diode trio, as explained, preceding. The alternator also is equipped with a fan (mounted on the rotor shaft) which induces air flow through the alternator to remove the heat created by the rectifier and stator. A capacitor also is utilized to protect the rectifier system from high voltages and to suppress radio noise. 90-95693 485 ELECTRICAL. SYSTEM - 3C-35 PRECAUTIONS The following precaution MUST BE observed when working on the alternator system. Failure to observe these precautions may result in serious damage to the alternator or alternator system. 1. DO NOT attempt to polarize the alternator. 2. DO NOT short across or ground any of the terminals on the alternator, except as specifically instructed in the Troubleshooting Tests". 3. NEVER disconnect the alternator output lead or battery cables when the alternator is being driven by the engine. 4. NEVER disconnect regulator lead from alternator regulator terminal when the alternator is being driven by the engine. 5. ALWAYS remove negative (-) battery cable from battery before working on alternator system. 6. When installing battery, BE SURE to connect the negative (-) (grounded) battery cable to negative (-) battery terminal and the positive (+) battery cable to positive (+) battery terminal. 7. If a charger or booster battery is to be used. BE SURE to connect it in parallel with existing battery (positive to positive: negative to negative). PERIODIC MAINTENANCE The following maintenance check should be performed every 50 hours or 60 davs (whichever comes first) in fresh water areas or every 25 hours or 30 days in salt water areas. Remove all battery cables from battery (before conducting the following check) to prevent accidentally shorting out electrical system. 1. Inspect entire alternator system for corroded or loose connections. 2. Check wiring for fraved or worn insulation. 3. Check alternator drive belt for excessive wear, cracks, fraving and glazed surfaces. Also, check drive belt tension and adjust, if necessary, as explained under "Drive Belt Tension Adjustment". 4. Check alternator mounting bolts for adequate tightness. 5. Inspect slip ring end frame flame arrestor screen for debris and clean, if necessary, using compressed air or a cloth. Screen MUST BE clean, or alternator mav overheat. TROUBLESHOOTING TESTS (ALTERNATOR ON ENGINE) Use the following tests in conjunction with the "Troubleshooting" in Section 1. Before proceeding with the tests, however, perform the following checks to eliminate possible problem areas. Also observe "Precautions", immediately preceding, to prevent damage to alternator system. 1. If problem is an undercharged battery, check to ensure that undercharged condition has not been caused by excessive accessory current draw or by accessories which have accidentally been left on. Also, check that undercharged condition has not been caused by running engine at too low a speed for extended periods of time. 2. Check physical condition and state of charge of battery, as outlined under "Storage Batterv" in "Section 3 Part A". Battery MUST BE at least 75% (1.230 specific gravity) of fully charged to obtain valid results in the following tests. If not, charge battery before testing system. 3. Inspect entire alternator system wiring for defects. Check all connections for tightness and cleanliness, particularly battery cable clamps and battery terminals. 4. Check alternator drive belt for excessive wear, cracks, fraying and glazed surfaces and replace if necessary. Also, check drive belt tension and adjust if necessary. as outlined under "Drive Belt Tension Adjustment". 3C-36 - ELECTRICAL SYSTEM 90-95693 1-888 CIRCUITRY TEST Perform the following tests, usinga0-20 volt DC voltmeter, to check that all of the circuits between the alternator and the other components within the alternator system are in good condition. Output Circuit 1. Connect positive voltmeter lead to alternator output terminal and negative lead to ground terminal on a.ternator. (Figure 1) 2. Wiggle engine wiring harness while observing voltmeter. Meter should indicate approximately batterv voltage and should not vary. If no reading is obtained, or if reading varies, check alternator output circuit for loose or dirty connections or damaged wiring. a - Ojtput Wire - Orange b - Excitation Wire - Purple c - Sensing Wire - Red/Purple d - Voltmeter (0-20 Volts) Figure 1. Alternator Output Circuit Test Excitation Circuit 1. Remove 4 screws which secure the regulator to the alternator. 2. Connect positive (+) voltmeter lead to regulator terminal (green wire) on alternator and negative (-) lead to ground terminal on alternator. (Test No. 1 in Figure 2) 3. Turn ignition switch to "On " position and note voltmeter reading. Reading should be 1.3 to 2.5 volts. 4. If no reading is obtained, an opening exists in alternator excitation lead or in excitation circuit of regulator. I nplug purple lead from regulator. Connect positive voltmeter lead to purple lead and negative voltmeter lead to ground. (Test No. 2 in Figure 2) If voltmeter now indicates approximate batterv voltage, voltage regulator is defective and must be replaced. If no voltage is indicated, check excitation circuit for loose or dirty connections or damaged wiring. 5. If reading is between .75 and 1.1 volts, rotor field circuit probably is shorted or grounded. Disassemble alternator and test rotor as outlined under "Alternator Repair", following. 6. If reading is between 0.0 and 7.0 volts, rotor field circuit probablv is open. Remove regulator and inspect for worn brushes or dirty slip rings. Replace brushes if less than W (6mm) long. If brushes and slip rings are in good condition, disassemble alternator and lest rotor, as outlined under Alternator Repair". Sensing Ciruit 1. Unplug red/purple lead from voltage regulator. 2. Connect positive voltmeter lead to red/purple lead and negative voltmeter lead to ground terminal. (Figure 3) 3. \oltmeter should indicate batterv voltage. If batterv voltage is not present, check sensing circuit (red/purple lead) for loose or dirlv connections or damaged wiring. a - Excitation Wire - Purple b - Sensing Wire - Red/Purple c - Green Wire d - Voltmeter (0-20 Volts) Figure 2. Alternator Excitation Circuit Test a - Output Wire - Orange b - Excitation Wire - Purple c - Sensing Wire - Red/Purple d - Voltmeter (0-20 Volts) Figure 3. Regulator Sensing Circuit Test 90-95693 485 ELECTRICAL. SYSTEM - 3C-37 VOLTAGE OUTPUT TEST CURRENT OUTPUT TEST Perform this test to determine if voltage regulator Perform this test to check if alternator is capable of producing rated current output, using a 0-50 amp DC ammeter. is operating correctly, using a 0-20 vol: DC voltmeter. Be sure that engine compartment is well- ventilated and that there are no gasoline vapors present (during the test) to prevent the possibility of an explosion and/or a fire, should a spark occur. 1. Disconnect negative (-) battery cable from battery. 2. Disconnect orange lead from alternator output terminal and connect ammeter in series between lead and output terminal. (Figure 4) Connect positive (+) side of ammeter toward output terminal. 3. Reconnect negative battery cable. 4. Remove coil hi-tension lead from distributor cap tcwer and ground it to block. Turn on all accessories and crank engine over with starter motor for 15-20 seconds. Turn off accessories and reinstall coil hi-tension lead. Start engine and adjust engine speed to 1500-2000 RPM. Quicklv observe ammeter. Reading should be at least 30 amps. 6. If reading is low, stop engine and connect a jumper lead between alternator output terminal and regulator terminal. (Figure 4) Repeat Steps 4 and 5. If reading is now within specifications, diode trio is faulty. Disassemble alternator and replace diode trio, as explained under "Alternator Repair", following. If reading is still low with jumper lead connected, perform "Voltage Regulator Test" following, to determine if fault is in regulator or alternator. a - Outpjt Wire - Orange b - Ammeter (0-50 Amps) c - Jumper Lead d - Regulator Terminal (Green Wire) Figure 4. Alternator Current Output Test IMPORTANT: Battery MUST BE fully charged (1.260 or above specific gravity) to obtain proper voltage reading in this test. If necessary, charge battery with a battery charger or allow engine to run a sufficient length of time to fully charge battery before taking reading. 1. Connect positive (+) voltmeter lead to positive battery terminal and negative (-) voltmeter lead to negative terminal. (Figure 5) 2. Start engine and run at fast idle until engine reaches normal operating temperature. Adjust engine speed to 1500-2000 RPM and observe voltmeter fcr highest reading. Reading snould be between 13.9 and 14.7 volts. 3. If reading is high, check for a loose cr dirty regulator ground lead connection. If connection is good (and sensing circuit checked out good in "Alternator System Circuitry- Test"), vcltage regulator is faulty and must be replaced. Be sure to disconnect battery cables before attempting to remove regulator. a - Output Wire - Orange b - Excitation Wire - Purple c - Sensing Wire - Red/Purple d - Jumper Lead (To Tan Wire and Ground) e - Voltmeter (0-20 Volts) Figure 5. Voltage Regulator Test 3C-38 - ELECTRICAL SYSTEM 90-95693 1-888 4. If reading is low. stop engine and remove 4 regulator attaching screws. Pull regulator away from alternator end frame to gain access to field regulator terminals. DO NOT Be sure that engine compartment is well-disconnect regulator terminals. Connect a jumper lead ventilated and that there are no gasoline vapors from the ground stud to the brush terminal that has a tan present (during the next steps) to prevent the wire attached. (Figure 5) Restart engine and gradually possibility of an explosion and/or fire, should a increase engine speed to 1500 RPM while observing volt- spark occur. meter. DO NOT allow voltage to exceed 16 volts. 5. If a voltmeter reading of 14.5 volts or above is now- obtained. voltage regulator is faulty and must be replaced. If voltmeter reading is below 14.5 volts, inspect brushes and slip rings for wear, dirt or damage. If brushes and slip DO NOT allow jumper wire to contact alterna-rings are good, alternator is faultv internallv. Disassemble tor end frame (in next step), as diode trio and alternator and test components, as outlined under "Alterregulator may be damaged. nator Repair", following. 90-95693 485 ELECTRICAL. SYSTEM - 3C-39 ALTERNATOR REPAIR REMOVAL DISASSEMBLY IMPORTANT: the following instructions are for 1. Disconnect negative (-) battery cable from battery. complete disassembly and overhaul of the alterna 2. Disconnect wiring harness from alternator. tor. In many cases, however, complete disassembly 3. Remove alternator brace to alternator attaching bolt, of alternator is not required and, in those cases, it is washer(s) and spacer (if used). necessary only to perform the operations required 4. Loosen alternator brace to engine attaching bolt and alter- to repair or replace the faulty part. nator mounting bolt, then pivot alternator inward and 1. Mount alternator in a vise so that rear end frame is facing remove alternator drive belt. vou. 5. Remove alternator mounting bolt, washers (if used), 2. Disconnect regulator leads from terminals on rear end spacer and nut and remove alternator. frame. Remove 4 regulator attaching screws, then pull regulator a wav from rear end frameand disconnect regulator field leads. Remove regulator rubber seal. 3. Remove 2 brush set attaching screw s and remove brush set. 1. Screw (6) 2. Lockwasher (6) 3. Flatwasher (4) 4. Regulator 5. Brush Set 6. Rubber Seal 7. Nut 8. Lockwasher (6) 9. Flatwasher (2) 10. Condenser 11. Nut 12. Lockwasher (2) 13. Flatwasher (2) 14. Insulating Washer (3) 15. End Frame 16. Insulating Sleeve - Long 17. Insulating Sleeve - Short 18. Negative (-) Rectifier 19. Positive (+) Rectifier 20. Insulator - Rectangular 21. Clip (2) 22. Screw (1) 23. Screw (2) 24. Stator 25. Rotor 26. Retaining Plate 27. Front Bearing 28. End Frame 29. Screw (3) 30. Spacer 31. Screw (3) 32. Fan 33. Pulley 34. Lockwasher 35. Nut Figure 1. Mando Alternator Parts View 3C-40 - ELECTRICAL SYSTEM 90-95693 1-888 4. Scribe a mark on rear end frame, stator and front end frame to ensure proper reassembly later. 5. Remove 3 screws which secure end frames and stator together. IMPORTANT: DO NOT insert screwdriver blades more than 1/16' (1.6mm) into openings (in next step), as stator windings may be damaged. 6. Separate rear end frame and stator assembly from front end frame and rotor assembly using 2 thin blade screwdrivers (positioned at 180° apart from one another) at thelocation shown in Figures 2 and 3. Lse the two slots, shown in Figure 2. to initially separate units. a - DO NOT Insert Screwdriver Blades More than 1/16" into Slots b - Rear End Frame c - Stator d - Front End Frame Figure 2. Separating Rear End Frame and Stator Assembly from Front End Frame and Rotor Assembly Assembly from Front End Frame and Rotor Assembly 90-95693 485 Figure 4. Removing Rectifiers 7. Place rear end frame and stator assemblv on the bench with stator downward. Be sure that bench is clean and free of metal chips. Remove nuts, washers, insulators and condenser from output and ground studs. 8. Turn end frame over (stator upward) and remove the three phillips head screws which secure rectifiers to end frame. (Figure 4) 9. Unsolder diode trio lead from the insulated regulator terminal. (Figure 5) 10. Unsolder the three (3) stator leads along with the three (3) coated leads from the negative (-) rectifier heat sink. (Figure 6) Place a needle nose pliers on diode terminal between solder joint and diode bodv (as shown in Figure6) to help prevent heal damage to diodes. Unsolder joints as quickly as possible and allow diode terminal to cool before removing pliers. ELECTRICAL. SYSTEM - 3C-41 IMPORTANT: With alternator disassembled to this point, stator, rectifier diodes, diode trio and rotor may be tested, as explained under "Component Testing", following. IMPORTANT: DO NOT clamp vise on rotor pole pieces when removing pulley nut (in next step), as pole pieces may be distorted. 11. Remove pullev retaining nut by clamping pulley in a vise (using an oversize \ -belt or protective jaws to protect pullev) and turning nut counterclockwise with a W wrench. (Figure 7) Remove lockwasher and slide pulley and fan from shaft. If pulley is "stubborn", it may be necessarv to use a universal puller. a - Negative (-) Heat Sink b - Stater Leads (3) c - Coated Leads (3) (2 Shown) Figure 6. Unsoldering Leads from Negative (-) Rectifier Heat Sink a - 7/8" Wrench b - Use Oversize V-Belt to Protect Pulley Figure 7. Removing Pulley Nut 3C-42 - ELECTRICAL SYSTEM b - Front Bearing Retaining Plate Figure 8. Removing Front Bearing Retaining Plate Frame 12. Remove the (3) phillips head screws and lockwashers which secure the front bearing retaining plate. (Figure 8) 13. Remove front bearing from front end frame usingan arbor press and a suitable size mandrel. (Figure 9) (Discard bearing.) 14. If rotor slip rings or rear bearing require replacement, entire rotor must be replaced. Farts cannot be purchased separately. CLEANING and INSPECTION 1. Clean all parts with a clean, soft cloth. DO NOT use solvent, or electrical components may be damaged. 2. Inspect the following parts for wear and damage: a. Brush set - inspect for cracked porcelain casing, damaged brush leads, poor brush lead solder connections, weak or broken brush springs or worn brushes. Replace brush set if brushes are less than Vi" (6mm) long. 90-95693 1-888 b. Rotor • inspect for stripped threads, scuffed pole piece fingers or damaged bearing surfaces (because of bearing turning on shaft). c. Rotor slip rings - clean slip rings with 400 grain (or finer) polishing cloth while spinning rotor in a lathe. Blow off dust with compressed air. Inspect slip rings for grooves, pits, flat spots or out-of-round [.002" (.051 mm) maximum] and replace, if present. d. Rotor shaft bearings - inspect for damaged seals, lack of lubrication, discoloration (from overheating) or excessive side or end plav. Hold inner race of bearings while turning outer race. Bearing should turn freely without binding or evidence of rough spots. e. Stator - inspect for damaged insulation or wires: also inspect insulating enamel for heat discoloration, as this is usually a sign of a shorted or grounded winding or a shorted diode. f. Regulator - inspect leads for damaged insulation. g. Frnni and rrar i-ml frames • inspect for cracks, distortion. stripped threads or wear in bearing bore (from bearing outer race spinning in bore). End frame(s) Ml ST BE replaced, if bearing has spun. Also, inspect bearing retainer recess in front end frame fcr damage. h. Fan - inspect for cracked or bent fins, broken welds (bi-rotational fan only) or worn mounting hole (from fan spinning on shaft). i. Pullev • inspect pullev mounting bore end for wear. Inspect drive surface of pullev sheaves for trueness, excessive wear, grooves, pits, nicks or corrosion. Repair damaged surfaces, if possible, with a fine file and a wire brush or replace pulley, if beyond repair, drive surfaces ML ST BE perfectly true and smooth, or drive belt wear will be greatlv accelerated. COMPONENT TESTING Rotor 1. Test rotor field circuit for opens, shorts or high resistance (Test I. Figure 10). usingan ohmmeter (set on Rxl scale), as follows: a. Connect one ohmmeter lead to each slip ring. b. Ohmmeter readingshould be4.2 to 5.5 ohms with rotor at room temperature 70° - 80° F (21° - 26° C). c. If reading is high or infinite (no meter movement), high resistance or an open exists in the field circuit. Check for poor connections between field winding leads and slip ring terminals. If cause for open or high resistance cannot be found, connect ohmmeter directly to slip ring terminals. If correct reading is now- obtained. or if reading is still high or infinite, replace complete rotor assemblv. d. If reading is low. a short exists in the field circuit. Inspect slip rings to be sure that thev are not bent and touching outer slip ring. Also be sure that excess solder is not shorting terminals to aft slip ring. If cause for short cannot be found, unsolder field winding leads from slip ring terminals and connect ohmmeter directly to leads. If correct reading is now obtained, or if reading is still low. slip rings and rotor field windings are shorted, and complete rotor assemblv must be replaced. 2. Test rotor field circuit for grounds (Test 2. Figure 10), usingan ohmmeter (set on Rxl scale) as follows: a. Connect one lead of ohmmeter to either slip ring and the other lead to rotor shaft or pole pieces. b. Meter should indicate no continuity (meter should not move). c. If continuitv does exist, rotor field circuit isgrounded. Inspect slip ring terminals to be sure that they are not bent and touching rotor shaft. Also be sure that excess solder is not grounding terminals to rotor shaft. If cause for ground cannot be found, unsolder field winding leads from slip ring terminals and connect ohmmeter between one of the leads and rotor shaft or pole pieces. If continuitv still exists, replace motor assemblv. If continuity is eliminated, replace slip rings. IMPORTANT: If alternator has output at low speeds, but no output at high speeds, rotor field winding may be shorting or grounding out, because of centrifugal force. Replace rotor, if all other electrical components test good. Stator IMPORTANT: Stator leads MUST BE disconnected from rectifier diodes and diode trio for this test. 1. Test stator for grounds (Test 1. Figure 11). using an ohmmeter (set on Rxl scale) as follows: a. Connect one lead of ohmmeter to one of the stator leads and the other lead to stator frame. Be sure that lead makes good contact with frame. b. Meter should indicate no continuity (meter should not move). If continuity does exist, stator isgrounded and must be replaced. 90-95693 485 ELECTRICAL. SYSTEM - 3C-13 2. Test for opens in stator. TEST 2 - Figure 11. using an ohmmeter (set on Rxl scale) as follows: a. Connect ohmmeter between each pair of stator windings (3 different ways). b. Continuity should be present in all 3 cases (meter should move). If it does not. one or more of the windings are open and stator must be replaced. 3. A short in the stator is difficult to detect without special equipment, because of the low windings resistance. If all other electrical components test out good, and alternator fails to produce rated output, stator probably is shorted and should be replaced. Also, examine stator for heat discoloration. as this usually is a sure sign of a short. Negative (-) Rectifier Diodes IMPORTANT: Rectifier diodes MUST BE disconnected from stator for this test. DO NOT use a test instrument with more than a 12-volt source (in the following test), as recti fier diodes may be damaged. 1. Connect one lead of on ohmmeter (set on Rxl scale) to negative (-) rectifier diode heat sink and the other lead to one of the rectifier diode terminals. (Figure 12) Note the reading. 2. Reverse leads and again note reading. 3. Meter shouid indicate a high or infinite resistance (no meter movement) when connected one way and a low reading when connected the other. If both readings are high or infinite, diode is open. If both readings are low. diode is shorted. 4. Repeat Steps l-thru-3 for 2 other rectifier diodes in heat sink. 5. Replace complete rectifier set. if any one of the diodes is shorted or open. a - Heat Sink b - Diode Terminal c - Test These 2 Diodes in Same Manner Figure 12. Testing Negative (-) Rectifier for Shorts or Opens DO NOT use a test instrument with more than a 12-volt source (in the following test), as recti fier diodes may be damaged. Positive (+) Rectifier Diodes and Diode Trio 1. Connect one lead of an ohmmeter (set on Rxl scale) to 'A" stud on positive (+) rectifier heat sink and the other lead lo one of the rectifier diode terminals. (Figure 13) (Note: Two of the diode terminals come up thru the diode trio circuit board.) Note the meter reading. 2. Reverse leads and again note reading. 3. Meter should indicate a high or infinite resistance (no meter movement) when connected one way and a low reading when connected the other. If both readings are high or infinite, diode is open. If both readings are low, diode is shorted. 4. Repeat Steps l-thru-3 for 2 other rectifier diodes in heal sink. 3C-44 - ELECTRICAL SYSTEM 90-95693 1-888 a - Stud b - Repeat Test between These Terminals and Stud Figure 13. Testing Positive (+) Rectifier Diodes for Shorts or Opens Figure 14. Testing Diode Trio for Shorts or Opens 5. Replace complete rectifier set, if any one of the diodes is shorted or open. 6. Connect one lead of an ohmmeter (set on Rxl scale) to the common side on the diode trio circuit board and the other lead to the other side of one of the three (3) trio diodes. (Figure 14) Note the reading. 7. Reverse leads and again note reading. 8. Meter should indicate a high or infinite resistance (no meter movement) when connected one wav and a low reading when connected the other. If both readings are high or infinite, diode trio is open. If both readings are low. diode Trio is shorted. 9. Repeat Steps 6-thru-8 for the other 2 diodes. 10. Replace positive (+) rectifier and diode trio assemblv if anv one of the dioeds is shorted or open. Condenser 1. I sing Magneto Analyzer and accompanying instructions, perform the following condenser tests: a. Condenser Capacity Test (must be .5 mfd). b. Condenser Short or Leakage Test. c. Condenser Series Resistance Test. 2. Replace condenser, if test results are not within specifications. REASSEMBLY 1. Install new front bearing into front end frame bearing bore usingan arbor press. (Figure 15) Ifnecessarv, usea bearing driver that contacts outer race onlv. 2. Install front bearing retaining plate using 3 phillips head screws and lockwashers. (Figure 16) a - Phillips Head Screws and Lockwashers b - Front Bearing Retaining Plate Figure 16. Installing Front Bearing Retaining Plate 90-95693 485 ELECTRICAL. SYSTEM - 3C-45 3. Slide front end frame over rotor. IMPORTANT: DO NOT clamp vise on rotor pole pieces when tightening pulley nut (in next step), or pole pieces may be distorted. 4. Slide fan spacer onto rotor shaft. Install fan, pulley, lock- washer and nut on shaft. Clamp pulley in a vise, using protective jaws or an old oversize V'-belt to protect pulley (Figure 7), and torque nut to specifications. Tighten vise only enough to allow tightening of nut. as excessive tightening mav distort pulley. IMPORTANT: The insulating washers MUST BE installed as shown or damage to the alternator WILL result. 5. Install positive (+) and negative (-) rectifier heat sinks, shown in Figure 17. 6. Position rear end frame and stator assembly over front end frame and rotor assembly and align scribe marks on each (scribed during disassembly). Hand-press end frames together, then install screws. Tighten screws securely. a - Positive (+) Rectifier Heat Sink b - Rectangular Insulator c - Lockwasher d - Screw - 1-1/2" (38mm) Long e - Screw -1/2" (13mm) Long; 2 Required f - Clip g - Negative (-) Rectifier Heat Sink h - Insulator i - Rear End =rame k - Nut j - Flat Washer I - Condenser Figure 17. Installing Positive (+) and Negative (-) Rectifier Heat Sinks 7. Place brush set in rear end frame cavity and secure with 2 mounting screws, as shown in Figure 18. Be sure to use outer-most mounting holes. Tighten screws securely. 8. Position rubber seal on regulator mounting surface. Connect regulator field leads and regulator lead to brush and regulator terminals (shown in Figure 18.), ther mount regulator with 4 screws. Connect ground terminal and secure with lockwashers and nuts. Tighten screws and nuts securelv. 3C-46 - ELECTRICAL SYSTEM c - Regulator Rubber Seal d - Insulated Regulator Terminal Figure 18. Installing Brush Set and Regulator IMPORTANT: Regulator field leads MUST BE connected as shown in Figure 18, or leads may be damaged by rotor slip rings during operation. INSTALLATION 1. Position alternator in mounting bracket ar.d install mounting bolt, washers (if used), spacer and nut. Place washers (if used), cn each side of spacer. DO .NOT tighten nut securely at this time. 2. Fasten alternator brace to alternator with bolt, washers and spacer (if used). DO NOT tighten bolt at this time. 3. Position alternator drive belt on pullevs and adjust tension as explained under "Drive Belt Tension Adjustment" . 4. Reconnect wiring harness to alternator (Figure 19) and negative batterv cable to batterv. a - Excitation Lead (Purple) c - Ground Lead (Black) b - Sensing Lead (Red/Purple) d - Output Lead (Orange) Figure 19. Wiring Harness Connected to Alternator 90-95693 1-888 470/485/488 CHARGING SYSTEM TORQUE SPECIFICATIONS Fastener Location Lbs. Ft. (N.m) Lbs. In. (N.m) Hose Clamps Securely Rotor 50 (68) Stator 45 (5) Voltage Regulator (Bolts) Securely Voltage Regulator (Nuts) Securely TOOLS/SEALANTS KENT-MOORE SPECIAL TOOLS Can be ordered from: Kent-Moore Tools. Inc. 29784 Little Mack Roseville, Ml 48066 Phone: (313) 774-9500 J-21058-20 Rotor Installation Tool J-6978-04 Rotor Removal Tool SEALANTS 92-25711 Quicksilver Liquid Neoprene 92-32609 Quicksilver Loctite "A" SPECIFICATIONS Model Amp Output (Max.) Rotation MCM/MIE 470, MCM 39 Bi-Rotational 485/488 90-95693 485 ELECTRICAL. SYSTEM - 3C-47 DESCRIPTION The electrical generating positon of this charging system is quite simple. It consists of six large permanent magnets (rotor), which are rotated by the crankshaft and move past a stationary iron lamination assembly wound with a single phase winding (stator). The complexity of this charging system is in the regulation of this output. Since the permanent magnets are always turned "full on", the output of the winding is also always at full potential. This differs from the automotive type where the output can easily be varied by controlling the strength of the rotating electromagnet. The regulator controls output by momentarily and completely disconnecting the output winding from the battery when the regulator senses that the battery is at its correct voltage. The disconnect periods are very short with frequency and duration dependent upon the needs of the battery. This disconnecting of the windings is done thru the use of a pair of silicon control rectifiers in the full wave rectifying bridge of the regulator. The regulators control of this on-off switching is programmed so that no electrical noise, output interruptions, or pulsing of the output current is detectable. PRECAUTIONS The following precautions MUST BE observed when working on the alternator system. Failure to observe these precautions may result in serious damage to the alternator or alternator system. 1. DO NOT attempt to polarize the charging system. 2. DO NOT short across or ground any of the terminals on the regulator, except as specifically instructed in the "Troubleshooting Tests". 3. NEVER disconnect the regulator output lead or battery cables when the alternator is being driven by the engine. 4. NEVER disconnect regulator lead from regulator terminal when the alternator is being driven by the engine. 5. ALWAYS remove negative (-) battery cable from battery before working on alternator system. 6. When installing battery, BE SURE to connect the negative (-) (grounded) battery cable to negative (-) battery terminal and the positve (+) battery cable to positive (+) battery terminal. 7. If a charger or booster battery is to be used, BE SURE to connect it in parallel with existing battery (positive to positive; negative to negative). PERIODIC MAINTENANCE The following maintenance check should be performed every 50 hours or 60 days (whichever comes first) in fresh water areas or every 25 hours or 30 days in salt water areas. 1. Inspect entire alternator system for corroded or loose connections. 2. Check wiring for frayed or worn insulation. REMOVAL/INSTALLATION For removal and installation instructions for removing the adjust the power steering belt (if equipped) refer to "Drive Belt rotor and stator assembly refer to "Section 6 Part B". To Tension Adjustment" (This section). 3C-48 - ELECTRICAL SYSTEM 90-95693 1-888 TROUBLESHOOTING TESTS (ON ENGINE) When performing the following procedure, be sure to observe the following: • Be sure that engine compartment is well ventilated and that no gasoline vapors are present, to avoid the possibility of a fire. • Before connecting or disconnecting any electrical connection, battery cables MUST BE REMOVED from battery to prevent possible personal injury or damage to equipment. A. The charging system may be connected to one or more batteries during these tests, however, these batteries must not be connected to any other charging source. B. Check that all connections are tight prior to starting tests. Insure that the battery posts and terminals are clean and making good contact. Verify with test equipment that wiring harnesses are not at fault. C. Examine the pins and sockets of the engine harness connector for burned, loose or dirty connections. Using a knife blade, spread the slot (in the male pins of this connector) slightly to insure good contact. D. Make sure alternator rotor is magnetized. IMPORTANT: Temporarily install ammeterin series with the orange (red/white) output lead from the regulator. This meter is required only for these tests, following: CONSTANT HIGH OUTPUT (Figure 1) 1. Remove one yellow--red wire from its regulator terminal and tape back temporarily. Run engine at 1000 RPM. Any output current indicates a stator short to ground. 2. Reconnect the vellow-red lead and reneat test with the other yel.ow-red lead. 3. If there is no output with either yellow-red lead in the above test, the regulator is bad. NO OUTPUT (Figures 2 and 3) 1. Remove the 2 yellow/red and the orange (red/white) leads from the regulator. Check the resistance between the regulator case and either yellow/red stud A near zero reading from either stud to the case indicates a bad regulator. a - Voltage Regulator b - Stator Wires - Yellow/Red Disconnect c - Output Wire - Orange (Red/White) Disconnect d - Sensing Wire - Red/Purple (Red) Figure 2. No Output Test (Regulator) 3. Check the resistance between the yellow/red leads. Resistance greater than 1 ohm indicates a bad stator. (Figure 3) a - Stator b - Stator Wires - Yellow/Red Figure 3. No Output Test (Stator) a - Rotor e - Voltage Regulator b - Stator f - Test Ammeter (0-50 Amps) c - Stator Wires - Yellow/Red g - Output Wire - Orange (Red/White) d - Sensing Wire - Red/=urple (Red) Figure 1. Constant High Output Test 90-95693 485 ELECTRICAL. SYSTEM - 3C-49 If Steps 2 and 3 tests show both parts to be good, proceed. 4. With all leads on the regulator, except the sense lead, run the engine at 1000 RPM and observe ammeter. Any charging rrent indicates a low voltage set point - replace regulator. (Figure 4) a - Sensing Wire - Red/Purple (Red) Disconnect b - Output Wire - Orange (Red/White) c - Stator Wires - Yellow/Red d - Voltage Regulator Figure 4. Low Output Test If there isn't any output, proceed. 5. Vi ith all leads reconnected, useajumper lead (with "alligator clips" at both ends). Clip one end of jumper lead to ground and the other end of the lead to one yellow-red terminal (on regulator). Run the engine at 1000 RPM and observe ammeter. Repeat this same test with the other yellow-red terminal. Both of these tests should indicate an output of at least 10 amps. If output is less - replace regulator. (Fiugre 5) a - Jumper Wire b - Sensing Wire - Red/Purple (Red) c - Voltage Regulator d - Stator Wires - Yellow/Red e - Output Wire - Orange (Red/White) Figure 5. Low Output Test IMPORTANT: Excessive resistance in the ammeter circuit can cause voltage regulator damage on MerCruiser 470/485 engines. To prevent this possibility, a Voltage Regulator kii (99502A8), which eliminates the ammeter circuit, has been released. The kit includes a voltage regulator, jumper wire ana installation instructions. Install this kit on any MerCruiser 470 (Serial No. 462558C and above) or 485 engine (originally equipped with an ammeter) with which recurring voltage regulatorfaiiures have been experienced. Refer to "Section 3, Part E" for installation instructions. VOLTAGE REGULATOR TEST Disconnect both batterv cables from hat tery and remove regulator from engine. Check regulator diodes (Figure ft) in connecting posi:ive ( + ) ohmmeter lead to one stator terminal (vellow/red) and negative (-) ohmmeter lead !o output (orange or red white) terminal. Meter Ml ST show conduction. Reverse ohmmeler leads. Meter Ml ST NOT show conduction. Repeal tesl for other stator (vellow/red) terminal. \OTE: Positive lend of ohmmeler shows conduction with a diode, as shown below. a - Ohmmeter b -Yellow/Rec' Terminals c - Red/Purple (3ec) Terminal c - Voitage Regulator e - Orange (Red/White) Terminal Figure 6. Checking Regulator Diodes (.heck voltage regulation point t;sir:g D.f'. variable voltage supply and ohmmeter (Figure 7). Connect \ ullage supplx positive (+) lead to sense terminal. Connect jumper wire form sense terminal to output terminal. Connect voltage supply negative (-) lead to ground on regulator case. Turn on voltage supply to lft-18 volts. Connect ohmmeter positve (+) iead to ground on regulator case and ohmmeter negative (-) lead to 3C-50 - ELECTRICAL SVSTEM SO-95693 485 one stator yellow/red terminal. Ohmmeter MUST NOT show conduction. If meter shows conduction, momentarily disconnect and reconnect it. If meter still shows conduction, voltage regulator is bad (regulation point too high) and must be replaced. If meter did not show conduction, slowly reduce voltage supply setting while observing ohmmeter. Meter MUST go into conduction at some voltage between 15 volts and 13.5 volts. If meter does not show conduction when supply voltage is reduced to between 15 and 13.5 volts, voltage regulator is bad (regulation point too low) and must be replaced. Repeat test for other stator vellow/red terminal. b - Voltage Regulator f - Sense Terminal c - Ohmmeter g-JtmperWire d - Yellow/Red Terminal Figure 7. Checking Voltage Regulator Point BATTERY ISOLATORS DUAL BATTERY CHARGING SYSTEMS USING A BATTERY ISOLATOR Battery isolators allow the addition of an auxiliary (second) battery to the MerCruiser electrical system, the auxiliary batterv is primarilv used as a power source for various accessories installed on the boat. The battery isolator will allow the alternator to charge both the cranking and auxiliary batteries at the same time while preventing accessories, connected to the auxiliary batterv, from drawing power from the cranking batterv. Mercury Marine does not manufacture any battery isolator systems. Battery isolators must be bought from an outside manufacturer. Mercury Marine suggests following the manufacturers instruction carefully. IMPORTANT: Alternators used on MerCruiser engines ARE NOT equipped with an isolation diode. Follow battery isolator manufacturer's instructions for wire gauge. Battery isolator installation must conform to BIA Low Voltage Wiring Standard No. 125-79. MerCruiser engines that meet the following requirements can use a battery isolator. MCM/MIE 470/MCM 485/488 1. Engines equipped with 86255A2 or 99502A9 Water Cooled Voltage Regulator. 2. MCM/MIE 470 (Serial No. 4625580 thru 5120655) with 77305A2 Water Cooled Voltage Regulator, must have a new 99502A8 Regulator installed. 3. Figures 1, 2, 3 or 4. ALL OTHER MODELS 1. All engines equipped with a 3-wire belt driven alternator. 2. We recommend 1-wire Delco alternators be replaced with a 3-wire belt driven alternator (78403A2) before installing a battery isolator. 3. Figures 5 or 6. Following are suggested wiring installations for MerCruiser engines. 90-95693 485 ELECTRICAL. SYSTEM - 3C-51 Figure 1. MCM/MIE 470 and MCM 485 with Amrrelsr (Prestolite Starter Motor) 90-95693 485 3C-52 - ELECTRICAL SYSTEM Figure 2. MCM/MIE 470 and MCM 485 with Voltmeter and Ammeter By-Pass Jumper Wire (Prestolite Starter Motor) 90-95693 485 ELECTRICAL. SYSTEM - 3C-53 Figure 3. MCM 470/485 with Engine Wiring Harness Wired for Voltmeter (Prestolite Starter Motor) 3C-54 - ELECTRICAL SYSTEM 90-95693 1-888 Figure4. MCM 470R/488R with EngineWiring Harness Wired for Voltmeter (Delco Remy Starter Motor) 90-95693 485 ELECTRICAL. SYSTEM - 3C-55 Figure 5. 3-Wire Belt Driven Alternator with Ammeter Circuit (Typical Wiring Shown) 90-95693 1-888 3C-56 - ELECTRICAL SYSTEM Figure 6. 3-Wire Belt Driven Alternator with Voltmeter Circuit (Typical Wiring Shown) 90-95693 485 ELECTRICAL. SYSTEM - 3C-57 SECTION 3 - ELECTRICAL SYSTEM PART D - INSTRUMENTATION INDEX Page Gauges 3D-1 Oil, Fuel and Temperature 3D-1 Battery Gauge 3D-1 Cruiselog 3D-2 Ammeter 3D-2 Vacuum Gauge 3D-3 Speedometer 3D-3 Tachometer 3D-3 Gauge Reolacement 3D-3 Senders 3D-4 Oil Pressure 3D-4 Dual Station Sender Identification 3D-4 Water Temperature 3D-4 Dual Station Sender Identification 3D-4 Fuel Tank Sender 3D-4 Flange Type 3D-4 Capsule Type 3D-5 Switches 3D-6 Ignition Key Switch 3D-6 Emergency Stop Switch 3D-6 Start/Stop Panel 3D-7 Audio Warning System 3D-7 Horn and Timer 3D-7 Oil Pressure Switch 3D-7 Switch Identification 3D-8 Water Temperature Switch 3D-8 Switch Identification 3D-8 Transmission Fluid Temperature Switch 3D-8 GAUGES OIL, FUEL and TEMPERATURE IMPORTANT: If testing proves gauge to be defective, it must be replaced as there is no repair available. 1. Turn ignition switch to "Off ". 2. Remove wire from terminal "S". (Figure 1) 3. Turn ignition switch to "Run". Gauges must be at "A" position. (Figure 2) a - Remove Wire b - Jumper Wire BATTERY GAUGE Figure 1. Testing Gauge IMPORTANT: Fully charged battery must be used. 4. Turn ignition switch "Off'. 5. Connect jumper wire from terminal "G " to terminal "S". 1. Turn ignition key to Run' position. 6. Turn ignition switch to "Run". Indicator needle must read 2. Gauge reading should be approximatelv w hat batterv volat "B" position. (Figure 3) tage is. (Figure 4) Shut key "Off. 7. Replace gauge if needle was not in positions as shown in Figure 2 and 3. Figure 4. Battery Gauge 90-95693 485 ELECTRICAL SYSTEM - 3D-1 3. If gauge is out of dash, connect jumper wires as shown in Figure 5. a - Jumper Wire - To Negative (-) Battery Terminal b - Jumper Wire - To Positive (+) Battery Terminal Figure 5. Jumper Wire Connections CRUISELOG 1. Turn ignition key to "Run" position. 2. If gauge is good, run indicator will be turning. (Figure 6) Turn key to "Of f position. 3. If gauge is out of dash, connect jumper wires as show n in Figure 7. a - Run Indicator Figure 6. Cruiselog Figure 7. AMMETER 1. Disconnect battery cables from battery. 2. Remove red/white (or orange) and red (or red/purple) wires from back of ammeter gauge. (Figure 8) 3. Connect positive (+) lead of service ammeter to red/white (or orange) wire (removed from gauge) and connect negative (-) lead of service ammeter to red wire (or red/purple) (removed from gauge). IMPORTANT: DO NOT allow wires to come in contact with metal or other wires. a - Red/White (or Orange) b - Red (or Red/Purple) Figure 8. Ammeter 3C-2 - ELECTRICAL SYSTEM 90-95693 485 4. Connect battery cables to battery. Ground engine high tension coil wire to engine block. Crank engine over approximately 10 seconds (to remove battery surface charge), then reconnect coil wire, start engine and run at approximately 3000 RPM while observing service ammeter. Ammeter should be registering alternator output. If charging system is in working condition, and service ammeter registers but ammeter gauge did not register, gauge is defective. VACUUM GAUGE 1. Disconnect vacuum hose from engine. Connect service vacuum gauge to engine and record engine vacuum readings at idle. 1000. 2000 and 3000 RPM. Reconnect vacuum hose and compare vacuum gauge readings (at specified RPM) with service gauge readings. Readings should be within 3 inches of vacuum of each other. IMPORTANT: Make sure that vacuum hose between gauge and engine is not leaking and that all connections are tight. SPEEDOMETER IMPORTANT: When testing speedometer gauge for accuracy, air pressure that is used for test must be regulated to specified PSI. DO NOT apply excessive air pressure to speedometer gauge. 1. Apply air pressure directly to speedometer gauge (specified in chart) and note gauge reading. Light tapping of pressure gauge is required during accuracy check. 2. If gauge readings are not within specifications, gauge is defective. Air Pressure Gauge PSI Speedometer Gauge MPH 5.3 20 ± 1 (32 km/hr ± 1.6) 27.8 45 ± 1 (72 km/hr ± 1.6) TACHOMETER 1. Connect a service tachometer to engine and compare readings. 2. Replace if not within specifications. TACHOMETER TYPE ALLOWABLE RANGE 6000 RPM ± 150 RPM 8000 RPM ± 200 RPM GAUGE REPLACEMENT 1. Disconnect battery cables from battery. 2. Remove wires from back of gauge. 3. Vacuum and speedometer: Remove hose. 4. Disconnect light socket. 5. Remove holding strap and remove gauge. 6. Position gauge assembly in appropriate mounting hole. 7. Install holding strap and nuts. Tighten nuts evenly and securely. IMPORTANT: DO NOT distort case or bracket by over-tightening. 8. Connect ground (black) wire to ground terminal, if gauge is not mounted in metal panel. 9. Connect other wires to gauge as shown in "Section 3. Part F". 10. Vacuum and Speedometer: Connect hose. 11. Install gauge light socket. 12. Coat all terminals with Liquid Neoprene. 13. Reconnect batterv cables to battery90- 95693 485 ELECTRICAL. SYSTEM - 3C-3 SENDERS OIL PRESSURE WATER TEMPERATURE IMPORTANT: Use following test procedure for There is no accurate test that can be done without special checking accuracy of oil pressure sender only. If oil equipment. Install new sender. pressure gauge indicates zero oil pressure, refer to "Troubleshooting" section. Dual Station Sender Identification 1. Remove wire from sender terminal. 2. Connect ohmmeter between sender terminal and sender Sender will have 334-L stamped on hex of sender for 470. 485 case. Check ohms reading without engine running (zero and 488 engines. All other engines use sender with 362-BC pressure), then check reading with engine running. Com stamped on hex. pare oil pressure and ohms readings as shown in following chart: FUEL TANK SENDER Flange Type (Figures 2 and 3) 1. Disconnect wire from terminal on sending unit and ground wire from sending unit mounting screw. 2. Remove sending unit from fuel tank. 3. Connect ohms meter between sending unit terminal and sending unit housing. 4. With float arm in "full" position (arm horizontal), ohmmeter should read 30 ohms (± 5 ohms). 08723 a -Positive Lead b -Negative Lead Figure 1. Oil Pressure Oi OiOi l ll Pressur PressurPressur e ee Ohms Reading (Lbs./Sq (Lbs./Sq(Lbs./Sq . .. In. In.In. ) )) Single Dual 0 227-257 113.5-128.5 20 142-162.5 71-81.3 40 91.7-113.6 45.9-56.8 80 9-49 11-24.5 Dual Station Sender Identification Sender will have 353-AM stamped on hex of sender. a -Ohmmeter Leads b -Float Arm Horizontal Figure 2. Arm Horizontal 3D-4 -ELECTRICAL SYSTEM 90-95693 485 5. ith float arm in "empty" position (arm vertical) meter Capsule Type (Figure 4) should read 240 ohms (± 5 ohms). Sender is defective if not within specifications. 1. Disconnect wire from termianl on fuel tank capsule. 2. Remove 2 screws and remove capsule assembly. 3. Place a magnet under fuel capsule. 4. Connect ohmmeter between fuel capsule terminal and metal portion of capsule housing. 08750 a - Ohmmeter Leads b - Capsule c - Magnet Figure 4. Ohmmeter and Magnet Turn magnet counterclockwise until fuel capsule indicator 08749 reads empty. Ohmmeter should read 240 ohms (±5 ohms). a - Ohmmeter Leads 6. Turn magnet clockwise until fuel capsule indicator reads fc - Float Arm Vertical "Full". Ohmmeter should read 30 ohms (± 5 ohms). Fuel Figure 3. Arm Vertical capsule is defective if not within specifications. 90-95693 485 ELECTRICAL. SYSTEM - 3C-5 SWITCHES IGNITION KEY SWITCH (Figure 1) EMERGENCY STOP SWITCH (Figures 2 and 3) IMPORTANT: White lead must be taped back to switch harness. 1. Remove both leads from connections. 2. Using a test meter, check (with the switch cap on) for continuity between black and green, no continuity must exist. 1. Before testing key switch, check all fuses and/or circuit breakers in electrical circuit which could prevent operation of starter. 2. With key switch in "Off', there should be no continuity between switch terminals. 3. With key switch in "Run", continuity will exist between switch terminal "B " to "A " and "B " to "I". There should be no continuity between terminal "C" and any other terminals. 4. With key switch in "Start", continuity will exist Between terminal "B" to "A", "B"to "I" and "B " to "C". 5. If ignition key switch tests bad, unsolder wire connections and remove switch. Test switch again, as in Steps 2-thru-5, preceding. If switch tests good, wiring in harness is bad. There should be no continuity between any harness wires with kev switch removed. 3. With cap off, continuity must exist between black and a - Black b - Green Figure 2. green. 08747 Figure 1. Switch Terminal Identification a - Black b - Green Figure 3. 3D-6 - ELECTRICAL SYSTEM 90-95693 485 START/STOP PANEL (Figure 4) Disconnect battery leads at battery before testing. Disconnect battery leads. 2. Check for continuity between the terminals on the start switch with a continuity meter. 3. No continuity should exist. 4. Depress switch button and continuity should exist. 5. Check stop switch in the same manner. 6. If continuity exists when in the open (not depressed) state, replace panel button. Figure 4. AUDIO WARNING SYSTEM HORN AND TIMER 1. Turn key to "Hun" position (engine off). 2. Wait 7 to 14 seconds for horn to sound. 3. If horn does not sound: a. Connect jumper wires as shown in F igure 1. b. If horn does not sound, replace it. 4. If horn worked in step 3: a. Connect jumper wires as shown in Figure 1. b. Repeat step 2. c. If horn sounds, problem is in tan/blue wire back to engine or switches on engine. a - Purple Wire b - Purple Jumper Wire c - Red Jumper Wire Figure 2. Timer Wiring OIL PRESSURE SWITCH (Figure 3) Refer to "Section 3. Part E" for switch locations. Switch is normally closed. 1. Remove wire from sender terminal. 2. Connect continuity meter between sender terminal and sender hex. Figure 3. ELECTRICAL. SYSTEM - 3C-7 90-95693 485 3. With engine not running, meter should indicate full Switch Identification (Figure 4) continuity. 4. Start engine. With engine running and engine oil pressure above 6 PSI (41 kPa). meter should indicate NO continuity. Switch Identification Switch has 364-AF stamped on hex of sender. WATER TEMPERATURE SWITCH Refer to "Section 3, Part E" for switch locations. Switch is normally open. 48952 SWITCH Opens 150° F - 170° F (66° C - 77° C) Closes 190° F - 200° F (88° C - 93° C) 87-86080 SWITCH Opens 175° F - 195° F (79° C - 91°C) Closes 215° F -225° F (102°C 107° C) a - 48952 Switch with Red Mylar Sleeve b - 87-86080 Switch with Black Mylar Sleeve Figure 4. Water Temperature Switches TRANSMISSION FLUID TEMPERATURE SWITCH Switch is located on transmission. Also, switch is normally open. This switch is used on MCM 330 (B-W) and MIE 230/260/340 engines. Model Seawater Cooled Engine Closed Cooled Engine MCM 120/140/165 (Note 1) (Note 1) MCM/MIE 470 MCM 485/488 (Note 2) MCM 898/228/260 (Note 1) (Note 1) MCM 898R/228R/260R (Note 1) (Note 1) MCM 330 (Note 1) MCM 330 (B-W) (Note 1) (Note 2) MCM 370 (Note 1) MIE 220/255/330 (Note 1) (Note 1) MIE 230/260/340 (Note 1) (Note 2) 87-88031 SWITCH 180° F - 200° F Opens (82° C - 93° C) Closes 220° F - 240° F (104°C 116° C) NOTES: 1. Uses 48952 switch 2. Uses 87-86080 switch 3C-8 - ELECTRICAL SYSTEM 90-95693 1-888 SECTION 3 - ELECTRICAL SYSTEM PART E - ELECTRICAL KITS INDEX Page Alternator 78403A2 3E-1 Voltage Regulator Kit 86255A3 and 99502A8 ... 3E-2 Audio Warning System Kit 86047A2 3E-4 Audio Warning System Kit 86047A3 3E-6 Resistance Wire Replacement Kit 84-94227A2 3E-12 Emergency Stop Switch 65503A2 3E-14 MCM 120/140 Wiring Harness Kit 84-86673A2 3E-16 MCM 165 Wiring Harness Kit 84-86674A2 3E-19 MCM 470/485 Wiring Harness Kit 84-86675A2 3E-22 MCM 898/228/260 Wiring Harness Kit 84-86676A2 3E-24 MCM 898R/228R/260R Wiring Harness Kit 84-98423A4 3E-26 MCM 330 Wiring Harness Kit 84-86683A2 3E-27 MIE 228/255/330 Wiring Harness Kit 84-86677A2 3E-29 ALTERNATOR 78403A2 (37 AMP) Installation Instructions NOTICE: This Alternator Replaces Delco 37 Amp Alternators (56045, 59755, 59756, 68085, 69729, 78477 and 90793) and All Motorola 37 Amp Alternators. 3. If alternator is being used to replace Delco Single-ire Alternators (56045. 59755. 59756. 68085 or 69729). connect wires as follows: (Figure 1) a. Fasten extension harness leads to engine at least once everv 18" (460mm) with sta-straps. making sure that leads clear all moving parts and DO NOT rub or get pinched. 1. Remove old alternator and install new alternator, using 4. If alternator is being used to replace Delco 3-W ire Alternasame mounting fasteners. tor (78477 or 90793) or Motorola Alternators, connect 2. Adjust alternator drive belt tension. wires as follows: (Figure 2) IMPORTANT: To comply with BIA standard wire a. Discard extension harness that is supplied with alter- color coding, some of the alternators and engine nator. wiring harnesses may be equipped with a red-5. Reconnect battery cables to batterv. purple lead (in place of a red lead) and a purple lead (in place of a white Figure 1. Wiring Connections When Replacing Delco Single-Wire Alternators (56045,59755, 59756, 68085 and 69729) 90-95693 485 ELECTRICAL SYSTEM - 3E-1 Figure 2. Wiring Connections When Replacing Delco 3-Wire Alternator (78477 or 90793) and Motorola Alternators VOLTAGE REGULATOR KIT 86255A3 and 99502A8 For MerCruiser 470 (Serial No. 4886620 and Above) and 485 Excessive resistance in the ammeter circuit (running from the regulator up to the ammeter and back to battery) could cause voltage regulator to malfunction. To eliminate this potential problem, the voltage regulator is shipped with the necessary hardware to by-pass the ammeter circuit. A battery meter (voltmeter) MUST BE purchased separately to replace ammeter in the dash. 90-95693 485 3C-2 - ELECTRICAL SYSTEM Regulator Installation 2. Install orange jumper wire (supplied in kit) between "Output" terminal and "Sense" terminal, as shown in Figure 1. 3. Coat ALL connections with Liquid Neoprene: then, slide rubber insulating boots (Figure 1) into position over "Sense" and "Output" terminals. 1. Install new voltage regulator, using original fasteners. Be sure to tighten fasteners securely. 4. Install water hoses (from kit), as shown in Figure 2. Figure 1. Orange Jumper Wire Installed Figure 2. Hose Installation (99502A8 Kit Only) Battery Meter (Voltmeter) Installation 1. Remove ammeter from dash. 2. Install batterv meter (voltmeter) into dash in accordance with instructions provided with gauge. Figure 3. Battery Meter Installation XOTE: If a separate sn itch (other than ignition snitch) is to be used for dash Lights, remove hex nut and screw, which secure metal link (Figure 3) to "/" terminal and light bulb socket, and remove link. Reinstall hex nut on "[" terminal and connect dash light wire to light bulb socket terminal with screw. 3. Connect black wire (disconnected from ammeter) to "G" (ground) terminal on battery meter. (Figure 3) 4. Connect white or purple wire (disconnected from ammeter) to "I " (ignition) terminal on battery meter (voltmeter). (Figure 3) 90-95693 485 ELECTRICAL SYSTEM - 3E-3 NOTE: If ammeter did not have a white or purple lead con-end of wire with at least 4 lavers of electrical tape. (Figure nected to it, use a purple extension wire and connect I 3) terminal on battery meter to "I" terminal on water temperature gauge or oil pressure gauge. [ "7" terminal is the one with white or purple wire(s) connected to it.} If an accessory fused panel is to be installed, be 5. Coat all electrical connections with Liquid \eoprene. sure to connect it at screw, nut and sleeve con 6. Connect red or red-purple wire (disconnected from ammenection and at black wire terminal on battery ter) to red-white or orange IGNITION SWITCH wire (dis meter, as shown in Figure 3. DO NOT connect connected from ammeter) with screw , hex nut and rubber accessory panel at any other location, as wires sleeve. (Figure 3) Coat connection with Liquid Xeoprene in wiring harness may be of insufficient size to before sliding sleeve over connection. handle current load. 7. Tape back red-white or orange wiring harness wire (disconnected from ammeter) and insulate ring terminal on 8. Reconnect batterv cables. AUDIO WARNING SYSTEM KIT 86047A2 For MCM 470/485/488 Installing Switches and Buzzer WATER TEMPERATURE HEAT SWITCH INSTALLATION 1. Drain closed cooling section of engine. 2. Remove plug from location shown in Figure 1 or 2 and. in its place, install water heat switch. (Figure 3) Lse teflon tape to seal threads and tighten securelv. 3. Connect 3 ft. (1 m) tan/light blue wire (from kit) to water temperature heat switch: route wire to the starboard side of engine and back to oil plug location shown in F igure 4. 4. Secure wire to engine wiring harness, being sure it will not come in contact with anv moving parts. a - Water Plug b - Thermostat Housing Figure 2. Water Plug Location [MCM 470 (Serial No. 6218037 and Above) and 485/488] 16601 Figure 3. Water Heat Switch a - Water Plug b - Thermostat Housing Figure 1. Water Plug Location (MCM 470 Serial No. 6208036 and Below) 3C-4 - ELECTRICAL SYSTEM 90-95693 1-888 a - Oil Plug Figure 4. Oil Plug Location OIL PRESSURE SWITCH INSTALLATION 1. Remove oil plug from location shown in Figure 4. 2. Install oil pressure switch (Figure 5) in location where plug was removed. Use teflon tape to seal threads arid Figure 6. Warning Buzzer tighten securelv. 3. Connect tan/light blue lead (from water temperature heat 4. Route tan/light blue wire from buzzer back to engine switch) to oil pressure switch. compartment, supporting w ire every 18". Be sure that wire does not chafe or get pinched and does not come in contact with bilge water or moving parts. 5. Connect tan/light blue lead from buzzer to engine water heat switch or oil pressure switch, whichever is more accessible. 6. Place decal (Figure 7) on bottom of glass face of water temperature gauge and oil pressure gauge. Figure 5. Oil Pressure Swtich WARNING BUZZER INSTALLATION (Figure 6) 1. Disconnect batterx leads, if not already disconnected. 2. Mount buzzer (Figure 6) under dashboard with 2 screws (from kit) in location that is not in obvious sight but is easily accessible for installation and maintenance. Location should not restrict buzzer sound and also should be within limits of 18" (457mm) purple lead. (Loac will be connected to instrument terminal in dashboard.) Buzzer is not external ignition-proof, therefore, DO NOT mounl buzzer in engine or fuel tank compartments. 3. Attach purple lead to "+ 12\" switched terminal of any adjacent gauge |purple to purple (BI \) or purple to white (earlier MerOuise.-)|. The attaching terminal should be "off when ignition switch is in Off" position. Figure 7. Decal (To Be Placed on Face of Gauge) Figure 8. Decal (To Be Placed on Dashboard) 7. Place decal (Figure 8) in convenient location on dashboard. 8. Fill engine Closed Cooling System with water/anti-freeze solution. 9. Reconnect battery ieads. 10. Test switch (horn), as explained on decal. (Figure 8) 11. Seal all electrical connections with Quicksilver Liquid Neoprene. 90-95693 485 ELECTRICAL. SYSTEM - 3C-5 Figure 9. Audio Warning System Wiring Diagram AUDIO WARNING SYSTEM KIT 86047A3 For MCM 120,140,165, 898, 228, 260, 330TR/TRS Installing Water Heat Switch (Figure 1) INSTALLING WATER HEAT SWITCH on IN-LINE ENGINES with STANDARD and CLOSED COOLING NOTE: On standard cooled engines, temperature switch is designed for thermostat housing 47587.42. If thermostat housing 63908A2 is on engine, '/&-27NPTF tapped hole must be drilled and tapped to 3/e-18\FTF. Remove housing to make modification, then blow out with compressed air to remove metal chips and reinstall housing with a new gasket. NOTE: On closed cooled engines, reducing bushing 22-52382 (not in kit) must be installed into thermostat housing before heat switch. 1. Drain cooling system. a - Plug b - Thermostat Housing Figure 2. In-Line Standard Cooling 2. Remove plug from thermostat housing at location shown in Figure 2 or 3. 3. Install water heat switch from kit into thermostat housing. Figure 1. Water Heat Switch Use teflon tape to seal threads and tighten securely. 90-95693 1-888 3C-6 - ELECTRICAL SYSTEM a - Plug b - Thermostat Housing Figure 3. In-Line Closed Cooling 4. Attach 3 ft. (914mm) tan/light blue wire (from kit) to heat switch with nut and lockwasher. 5. Route tan/light blcc wire toward starboard side, then back to oil sender (to bs removed later). Secure wire to wire harness (located on starboard side of engine), being sure that wire will not come in contact with hot spots or moving parts. INSTALLING WATER HEAT SWITCH on V-8 ENGINES with STANDARD COOLING XOTE: MCM 898. 228. 260 and 330 -check thermostat housing to determine if housing is the new stvle or old style. ( Figure.4) Xew style thermostat housing has the hole (in which heat switch will be Installed) threaded on the same angle as the hose connection above it. If hole is not threaded on the same angle, thermostat housing is the old style and must be replaced with new style thermostat housing (78984 A1) on 228 and260 models or (79468A I) on 330 models. If898 model is equipped icith old style thermostat housing, install water heat switch in the intake manifold, as explained in Step 4. 1. Drain cooling system. 2. Disconnect hoses from thermostat housing. 3. Remove thermostat housing (Figure 5) from engine and scrape gasket material from all mating surfaces. 4. Install water heat switch as follows: a. On 898 models with old style thermostat housing (1) Remove pipj plug from intake manifold arid install water heat switch in its place, using teflon tape to *eal threads. (Figure 6) Tighten water hea: switch securelv. (2) Attach 3 ft. (914mm) tan/light blue wire (from kit) to switch with nut and lockwasher. Route wire over intake manifold to and along port rocker arm cover and down toward oil filter (oil pressure switch to be installed in this location later). Secure wire to water hose, being sure that wire does not come in contact with hot spot on intake manifold. (Figure 6) (3) Reinstall thermostat housing, using Perfect Seal and new gasket from kit. Torque screws to 30 lbs. ft. (41 N.m). (4) Reconnect water hoses (removed in Step 2) lo their respective locations. b. On all oliier models (except 898 with old stvle ihermostat housing) 90-95693 485 a - Threads Cut at an Angle to Hose Connection b - Threads Cut at Same Angle as Hose Connection Figure 4. New and Old Style Thermostat Housings a - Thermostat Housing b - Pipe Plug (on Aft Side of Thermostat Housing; Hidden) Figure 5. V-8 Standard Cooling Thermostat Housing a - Water Heat Switch b - Tan/Light Blue Wire (Route and Fasten as Shown) c - Intake Manifold Hot Spot d - Port Rocker Arm Cover e - Secure Wire to This Water Hose Figure 6. Water Heat Switch Installed (1) Install water heat switch into alt side of thermostat housing, using teflon tape to seal threads. (Figure 7) Tighten waier heat switch securely. IMPORTANT: MCM 898R, 228R and 260R Models - check water heat switch to ensure that switch does not interfere with thermostat. If interference does exist, thermostat and related parts must be rearranged as shown in Figure 10. ELECTRICAL. SYSTEM - 3C-7 a - Thermostat Housing b - Water Heat Switch Figure 7. Water h,leat Switch Installed on Aft Side of New Style Thermostat Housing (2) Install thermostat housing with new gasket (with continuii\ rivets) from kit. Torque screws to 30 lbs. fl. (41 N.m). (3) Attach 3ft. (914mrn) tan/light blue wire (from kit) to heat switch with nut and lockwasher. Route wire along port rocker arm cover and down toward oil filter (oil pressure switch to be installed in this location later). Secure wire to water hose, being sure thai wire does not come in contact with hoi spot on intake manifold. (Figure 8) (4) Reconnect water hoses (removed in Step2) to their respective locations. 13590 a - Water Heat Switch b - Tan/Light Blue Wire (Route and Fasten as Showr) c - Intake Manifold Hot Spot d - Port Rocker Artr Cover e - Secure Wire to This Water Hose Figure 8. Water Heat Switch Wire Properly Routed 13589 INSTALLING WATER HEAT SWITCH on V-8 ENGINES with CLOSED COOLING 1. Drain cooling system. 2. Remove thermostat housing and cover, then scrape gasket material from all mating surfaces. 3. Remove pipe plug from front of thermostat housing and install water heat switch in its place, using teflon tape to seal threads. (Figure 9) Tighten heat switch securely. 4. Install thermostat and related parts in sequence shown in Figure 9. a - Water Heat Switch b - Ground Gasket (Housing to Intake Manifold) c - Pipe Plug (Hidden) d - Thermostat Housing e - Thermostat f - Cork Gasket (Thermostat to Sleeve) g - Sleeve (Turned in Lip Down) h - Gasket (Thermostat Housing to Cover) i - Thermostat Housing Cover j - Lockwashers k - Bolts Figure 9. V-8 Closed Cooling Thermostat Housing Assembly 3C-8 - ELECTRICAL SYSTEM 90-95693 485 IMPORTANT: Check water heat switch to ensure 5. Install thermostat housing and cover, using gasket (with that heat switch DOES NOT interfere with thermo continuity rivets) from kit and new thermostat cover stat. If interference does exist, thermostat and re- gasket. (Figure 9) Use Perfect Seal on gasket cover before lated parts MUST BE rearranged as shown in Figure installing. Torque bolts to 30 lbs. ft. (41 N.m). 10. 6. Attach 3 ft. (914mm) tan/light blue wire (from kit) to switch with nut and lockwasher. 7. Route wire to and along port rocker arm cover and down toward oil filter (oil pressure switch to be installed in this location later). Secure wire to water hose, being sure that wire does not come in contact with hot spot on intake manifold, as shown in Figure 6. a - Thermostat c - Sleeve (Turned in Lip Up) b - Cork Gasket d - Thermostat Housing Figure 10. Thermostat and Related Parts Rearranged if Heat Switch Interferes with Thermostat 90-95693 485 ELECTRICAL. SYSTEM - 3C-9 Installing Oil Pressure Switch (Figure 11} Figure 11. Oil Pressure Switch INSTALLING OIL PRESSURE SWITCH on IN-LINE ENGINES 1. Disconnect both battery leads at battery. 2. Disconnect wire from oil sender and remove sender (also nipple and elbow, if so equipped). 3. Install nipple, then tee fitting (from kit), using teflon tape to seal threads. (Figure 12) 4. Install oil pressure switch and oil sender in position on tee as shown in Figure 12. Tighten fittings securelv. 5. Reconnect wire to oil sender (previouslv removed) and connect wire from heat switch to oil pressure switch. Torque nut to 15 lbs. in. (1.7 N.m). a - Oil Sender c - Nipple b - Oil Pressure Switch d - Tee Fitting Figure 12. Oil Pressure Switch Installed on In-Line Engines INSTALLING OIL PRESSURE SWITCH cr. V-2 ENGINES 1. Remove oil plug from location shown i:i Figur:' 13 :;r 2. On big block \-8's. install oil pressure switch in :.'.zcc .." plug. On small block \ -8's. install reducer (fro::, k::, av.c. t,:'. pressure switch in place of plug. I se teflon tape :o s;:r.! threads and tighten fittings securelv. 3. Connect wire from heat switch to oi! pressure s»wi:s. in. ! i.7 \ .:::•. a - Oil Plug Figure 13. Oil Plug Location on Small Block V-8 E: a - Oil Plug Figure 14. Oil Plug Location on Big Block V-8 Er.rir.ss 3E-10 - ELECTRICAL SYSTEM sC-SircES oc Installing Warning Buzzer (Figure 15) Figure 18. Audio Warning System Wiring Diagram 1. Disconnect battery leads, if not already disconnected. 2. Mount buzzer (Figure 15) under dashboard with 2 screws (from kit) in location that is not in obvious sight but is easily accessible for installation and maintenance. Location should not restrict buzzer sound and also should be within limits of 18" (460mm) purple lead. (Lead will be connected to instrument terminal in dashboard.) 6. Place decal (Figure 16) on bottom of glass face of water temperature gauge and of oil pressure gauge, if equipped. 7. Place decal (Figure 17) in convenient location on dashboard. Buzzer is not external ignition-proof, therefore, DO NOT mount buzzer in engine or fuel tank compartments. 3. Attach purple leac to "+ 12V" switched terminal of any adjacent gauge [purple to purple (BIA) or purple to white (earlier MerCruiser)]. The attaching terminal should be "off" when ignition switch is in "Off" position. 4. Route tan/light blue wire from buzzer back to engine compartment, supporting wire every 18". Be sure that wire does not chafe or get pinched and does not come in contact with bilge water or moving parts. 5. Connect tan/light blue lead from buzzer to engine water heat switch or oil pressure switch, whichever is more accessible with lockwasher and nut. Torque nut to 15 lbs. in. (1.7 N.m). (DO NOT over-tighten.) Figure 15. Warning Buzzer Figure 16. Decal (To Be Placed on Face of Gauge) ENGINE SENSOR HORN WILL SOUND WHEN OIL PRESSURE IS TOO LOW OR TEMP. IS TOO HOT TO TEST HORN 1. TURN KEY TO ON POSITION (ENGINE OFF) 2. WAIT 7 TO 14 SEC. FOR HORN TO SOUND Figure 17. Decal (To Be Placed on Dashboard) 8. Reconnect battery leads. 9. Fill Closed Cooling System (on engines so equipped) with water/anti-freeze solution. 10. Test switch (horn) as explained on decal. (Figure 17) 11. Seal all electrical connections with Liquid Neoprene. 90-95693 485 ELECTRICAL SYSTEM - 3E-11 Resistance Wire Replacement Kit 84-9422742 Installation Instructions 1. Determine if engine is equipped with a 1 or 3 wire 2. Install new resistance. (Figure 4. 5. 6 or 7; alternator system (Figure 1, 2 or 3). Refer to Figure 7 if resistance w ire is to be installed on a 470.485 or 488 Model. Figure 3. 3-Wire Motorola or Mando Alternators Figure 1.1-Wire Delco Alternator Figure 2. 3-Wire Delco Alternator 3E-12 - ELECTRICAL SYSTEM 3C-S56S3 435 a - Disconnect Damaced White or Purple (Stainless Steel Core) c - Attach Ring Terminal End of NEW Resistance Wire to Ignition Resistance Wire From Ignition Coil and Tape Back to Harness Coil and Coat Connection With Quicksilver Liquid Neoprene b - Strip Outer Insulating Jacket of White or Purple (Copper Core) Wire. Wrap and So der Copper End of NEW Resistance Wire to White or Purple Wire Insulate Junction. Figure 5.3-Wire Alternator System With or Without Electric Choke (Typical) a - Disconnect Damaged White (Stainless Steel Core) Resistance Wire From Ignition Coil and Tape Back to Harness b - Strip Outer Insulating Jacket of White (Copper Wire) Wire Wrap and Solder Copper End of NEW Resistance Wire :o White Wire. Insulate Junction, c - Attach Ring Terminal End of NEW Resistance Wire to Ignition Coil and Coat Connection With Quicksilver Liquid Neoprene Figure 6.1-Wire Delco Alternator System WITH Electric Choke a - Disconnect Damaged Purple (Stainless Stee Core) Resistance Wire From Ignition Coil and Tape Back to Harness b - Strip Outer Insulating Jacket of Purple (Copper Core) Wire. Wrap and Solder Copper End of NEW Resistance Wire to Purple Wire. Insulate Junction, c - Attach Ring Terminal End of NEW Resistance Wire to Ignition Coil and Coat Connection With Quicksilver Liquid Neoprene Figure 7. MerCruiser 470/485/488 Resistance Wire Replacement 90-95693 485 ELECTRICAL. SYSTEM - 3C-13 EMERGENCY STOP SWITCH 65503A2 INSTALLATION INSTRUCTIONS IMPORTANT: Emergency stop switch is supplied with a second cap to be used as a spare (to enable engine to be started, in case first cap is lost). Keep spare cap in a handy place aboard boat. 1. Route stop switch wire harness to engine so that it will not chafe or flex unnecessarily. Secure harness with sta-straps provided. 2. Check stop switch operation after installation is completed. 3. Coat all electrical connections with Liquid Neoprene (92-25711) after checking switch operation. 4. Attach stop switch cap to operator's person with a suitable cord (lanyard). Length of cord should be no longer than absolutely necessary and should have a minimum breaking strength of 100 lbs. (45kg). IMPORTANT: To prevent the possibility of damage to ignition components, turn ignition switch to "Off" position as soon as possible after safety stop switch has been activated. 5. To reset stop switch after activation, simply install stop switch cap with a straight firm push. MerCruiser Engines with Breaker Point Ignition 1. Tape white stop switch harness lead to harnessand insulate with at least two layers of electrical tape. 2. Connect black stop switch harness lead to ignition coil negative (-) terminal along with existing wires. (Figure 1 or 2) 09022A 3. Connect green stop switch harness lead to convenient engine ground. 4. Coat connections with Liquid Neoprene. 09051 a - Negative (-) Coil Terminal Figure 1. Wire Location (Typical 4 and 6-Cylinder MerCruiser Engines with Breaker Point Ignition) a - Negative (-) Coil Terminal Figure 2. Wire Location (Typical 8-Cylinder MerCruiser Engine with Breaker Point Ignition) 3E-14 - ELECTRICAL SYSTEM 90-95693 485 MerCruiser Engines with Thunderbolt IV HEI 2. Connect green stop switch harness lead to distributor terminal which has white-green lead already connected on it. Ignition (Figure 3) 3. Connect black stop switch harness lead to convenient engine ground. 1. Tape white stop switch harness lead to harness and insulate 4. Coat connections with Liquid Neoprene. with at least two layers of electrical tape. Figure 3. Wire Location [MerCruiser Engines with Thunderbolt IV (HEI) Ignition] 90-95693 485 ELECTRICAL. SYSTEM - 3C-15 WIRING HARNESS KIT 84-98423A4 For MCM 898R/228R/260R Stern Drive Engines INSTALLATION INSTRUCTIONS a - Wiring Harness b - J-Clamp (9/32" Attaching Hole) Figure 1. Wiring Harness Fastened to Exhaust Manifold NOTE: The fasteners, which are provided with this wiring harness, ML ST BE used, as explained in the following instructions, when the harness is installed on MCM 120 Engines below Serial A o. 5263237 and MCM 140 Engines below Serial No. 5279046. Engines with serial numbers above those listed already have the fasteners installed. 1. Remove (and discard) old wiring harness. Retain harness mounting plate and 4 attaching screws and all terminal fasteners. 2. Install wiring harness receptacle in wiring harness bracket and secure with mounting plate and 4 screws (retained in Step 1). 3. Route wiring harness and install fasteners provided with harness, as follows: a. Route section of harness (containing orange wire) to port side of engine. Install small J-clamp with 9/32" (7mm) attaching holes to bottom side of exhaust manifold with screw, as shown in Figure 1, and tighten securelv. Route harness thru clamp and bend clamp shut. IMPORTANT: Be sure that wiring harness is positioned so that the harness protector is located between the flywheel housing and bottom edge of manifold. (Figure 2) b. Remove screw from flvwheel housing (at the serial number plate) and install large J-clamp with 13/32" (10mm) attaching hole, as shown in Figure 2. Torque screw to 21 lbs. ft. (28 N.m). Route harness thru clamp and bend clamp shut. c. Remove screw from ignition coil mounting bracket and install medium J-clamp with 11/32" (9mm) attaching hole, as shown in Figure 3. Tighten screw securely. Route end of harness thru clamp and bend clamp shut. Position harness leads so that wires do not contact fuel line. a - Flywheel Housing Attaching Screw c - Wiring Harness b - J-Clamp (13/32" Attaching Hole) d - Harness Protector Figure 2. Wiring Harness Fastened to Flywheel Housing 90-95693 485 3E-16 - ELECTRICAL SYSTEM 4. If engine is equipped with a fuse on starter solenoid, remove (and discard) fuse. 5. Connect wiring harness leads to electrical components, as Failure to adequately insulate the purple and shown in F igure 4, being sure to complete the following: red-purple leads, as explained above, can re- a. Position insulator boots over terminals on wires so sult in electrical failure. equipped. b. Apply a coat of Liquid Neoprene to all termina. connections which are not protected by an insulator boot. c. Place heat shrink tubing (supplied with kit) over end of leads coming from alternator. Connect purple engine harness lead to purple (or white) alternator lead. Connect red-purple engine harness lead to red-purple (or red) alternator lead. Position heat shrink tubing over connections and heat with heat gun until secure. d. MCM engines, that are equipped with Delco single-wire alternators, do not use the purple and red-purple alternator leads (items "c" and "d" in Figure 4). On these engines, the purple and red-purple leads MUST BE insulated and taped back to wiring harness, as follows: 1) Fold terminal on end of purple lead back against purple lead and secure with electrical tape. Insulate with at least 4 layers of electrical tape completely covering the exposed metal of the terminal. 2) Fold termir.al on end of red-purple lead back against red-purple lead and secure with electrical tape. Insulate with at least 4 layers of electrical tape completely covering the exposed metal of the terminals. 3) Fold insulated purple and red-purple leads back against harness and secure with electrical tape. a - Ignition Coil b - J-Clamp (11/32" Attaching Hole) Mounting Bracket c - Wiring Harness Figure 3. Wiring Harness Fastened to Ignition Coil Mounting Bracket 6. After making all necessary harness connections, reconnect positive (+) batterv cable to positive balterv terminal and negative (-) battery cable to negati\e battery terminal. 12010 90-95693 485 ELECTRICAL. SYSTEM - 3C-17 a - Orange Wire - Connect to Alternator Output ("BAT") Terminal b - Black Wire - Connect to Alternator Ground Terminal *c- Purple Wire - Connect to Alternator Purple (or White) Wire •d - Red-Purple Wire - Connect to Alternator Red-Purple (or Red) Wire e - Harness Protector f - Black Wire - Connect :o Shift Interrupter Switch Terminal Block Mounting Screw g - Gray Wire - Connect to Insulated Terminal on Shift Interrupter Switch Terminal Block h - Receptacle i - Black Wire - Connect to Flywheel Housing Attaching Screw on Starboard Side of Engine j - Black Wire - Connect to Small Lower Terminal on Slave Solenoid k - Red-Purple Wire - Connect to One Large Terminal on Slave Solenoid I - Yellow-Red Wire - Connect to Other Large Terminal on Slave Solenoid m - Yellow-Red Wire - Connect to Small Upper Terminal cn Slave Solenoid n - Brown-White Wire - Connect to Insulated Terminal on Trim Position Sender Terminal Block o - Red Wire - Connect to Large Terminal on Starter Mounted Solenoid p - Yellow-Red Wire - Connect to "S" Terminal on Starter Mounted Solenoid q - Purple-Yellow Wire - Connect to "R" Terminal on Starter Mounted Solenoid r - Light Blue Wire - Connect to Oil Pressure Sender on Side of Engine Block s - Gray Wire - Connect to Negative (-) Terminal on Ignition Ceil t - Purple and Purple-Yellow Wires - Connect to Positive (-) Terminal on Ignition Coil u - Tan Wire - Connect to Water Temperature Sender on Front of Thermostat Housing v - Red Wire - Connect to Upper Terminal on Circuit Breaker w - Red-Purple Wire - Connect to Lower Terminal on Circuit Breaker x - Insulator Boot * Install and shrink sleeve (supplied with harness) over these quick disconnect terminals. Be sure that all exposed metal on the terminals is covered. Figure 4. Wiring Harness (84-86673A2) Electrical Connections 3C-18 - ELECTRICAL SYSTEM 90-95693 485 WIRING HARNESS KIT 84-86683A2 For MCM 330 Stern Drive Engine INSTALLATION INSTRUCTIONS \OTE: The fasteners, which are provided with this wiring harness. Ml ST BE used, as explained in the following instructions, when the harness is installed on MCM 165 Engines below Serial Xo. 5297841. Engines with Serial No. 5297841 and above already have the fasteners installed. 1. Remove (and discard) old wiring harness. Retain harness mounting plate and 4 attaching screws and a 1 terminal fasteners. 2. Install wiring harness receptacle in wiring harness bracket and secure with mounting plate and 4 screws (retained in Step 1). 3. Route wiring harness and install fasteners provided with harness, as follows: a. Route section of harness (containing orange wire) to port side of engine. Remove lA" screw from bottom of exhaust manifold and install J-clamp with 9/32" (7mm) attaching hole, as shown in Figure 1. Tighten screw securely. Route harness thru clamp and bend clamp shut. 12001 a - Flywheel Housing Attaching Screw c - Wiring Harness b - J-Clamp (13/32" Attaching Hole) d - Harness Protector Figure 2. Wiring Harness Fastened to Flywheel Housing a - Wiring Harness b - J-Clamp (9/32" Attaching Hole) Figure 1. Wiring Harness Fastened to ExhaustManifold IMPORTANT: Be sure that wiring harness is positioned so that the harness protector is located between the flywheel housing and bottom edge of manifold. (Figure 2) b. Remove screw from flywheel housing (at the serial number plate) and install large J-clamp with 13/32" (10mm) attaching hole, as shown in Figure 2. Torque screw to 21 lbs. ft. (28 N.m). Route harness thru clamp and bend clamp shut. c. Remove nut. that secures starter brace to side of engine, and install smaller j-clamp with 13/32" attaching hole, as shown in Figure 3. Torque nut to 144 in. lbs. (16 N.m). Route harness thru J-clamp and bend clamp shut. a - Starter Brace b - J-Clamp (13/32" Attaching Hole) c - Wiring Harness Figure 3. Wiring Harness Fastened to Starter Brace d. Remove screw from ignition coil mounting bracket and install J-clamp with I l '32" (9mm) attaching hole, as shown in Figure 4. Tighten screw securelv. Route end of harness thru clamp and bend clamp shut. Position harness lead:- so thai thev do not ccntael fuel line. 4. If engine is equipped with a fuse on -tarter solenoid, remove (and discard) fuse. 90-95693 485 ELECTRICAL SYSTEM - 3E-19 5. Connect wiring harness leads to electrical components, as shown in Figure 4, being sure to complete the following: a. Position insulator boots over terminals on wires so equipped. b. Apply a coat of Liquid Neoprene to all terminal connections which are not protected bv an insulator boot. c. Place heat shrink tubing (supplied with kit) over end of leads coming from alternator. Connect purple engine harness lead to purple (or white) alternator lead. Connect red-purple engine harness lead to red-purple (or red) alternator lead. Position heat shrink tubing over connections and heat with heat gun until secure. d. MCM engines, that are equipped with Delco single-wire alternators, do not use the purple and red-purple alternator leads (items "c" and "d " in Figure 5). On these engines, the purple and red-purple leads MUST BE insulated and taped back to wiring harness, as follows: 1) Fold terminal on end of purple lead back against purple lead and secure with electrical tape. Insulate with at least 4 lavers of electrical tape completely covering the exposed metal of the terminal 2) Fold terminal on end of red-purple lead back against red-purple lead and secure with electrical tape. Insulate with at least 4 lavers of electrical tape completely covering the exposed metal of the terminals. 3) Fold insulated purple and red-purple leads back against harness and secure with electrical tape. a - Ignition Coil Mounting Bracket b - J-Clamp (11/32" Attaching Hole) c - Wiring Harness Figure 4. Wiring Harness Fastened to Ignition Coil Mounting Bracket 6. After making all necessarv harness connections, reconnect positive ( + ) battery cable to positive battery terminal and negative (-) battery cable to negative balterv terminal. 90-95693 1-888 3C-90 - ELECTRICAL SYSTEM a - Orange Wire - Connect to Alternator Output ("BAT") Terminal b - Black Wire - Connect to Alternator Ground Terminal *c - Purple Wire - Connect to Alternator Purple (or White) Wire *d - Red-Purple Wire - Connect to Alternator Red-Purple (or Red) Wire e - Harness Protector f - Black Wire - Connect to Shift Interrupter Switch Terminal Block Mounting Screw g - Gray Wire - Connect to Insulated Terminal on Shift Interrupter Switch Terminal Block h - Receptacle i - Black Wire - Connect to Flywheel Housing Attaching Screw on Starboard Side of Engine j - Black Wire - Connect to Small Lower Terminal on Slave Solenoid k - Red-Purple Wire - Connect to One Large Terminal on Slave Solenoid I - Yellow-Red Wire - Connect to Other Large Terminal on Slave Solenoid m - Yellow-Red Wire - Connect to Small Upper Terminal on Slave Solenoid n - Brown-White Wire - Connect to Insulated Terminal on Trim Position Sender Terminal Block o - Red Wire - Connect to Large Terminal on Starter Mounted Solenoid p - Yellow-Red Wire - Connect to"S" Terminal on Starter Mounted Solenoid q - Purple-Yellow Wire - Connect to "R" Terminal on Starter Mounted Solenoid r - Light Blue Wire - Connect to Oil Pressure Sender on Side of Engine Block s - Gray Wire - Connect to Negative (-) Terminal on Ignition Coil t - Purple and Purple-Yellow Wires - Connect to Positive (+) Terminal on Ignition Coil u - Tan Wire - Connect to Water Temperature Sender on Front of Thermostat Housing v - Red Wire - Connect to Upper Terminal on Circuit Breaker w - Red-Purple Wire - Connect to Lower Terminal on Circuit Breaker x - Insulator 3oot * Install and shrink sleeve (supplied with harness) over these quick disconnect terminals. Be sure that all exposed metal on the terminals is covered. Figure 5. Wiring Harness (84-86674A2) Electrical Connections 90-95693 485 ELECTRICAL. SYSTEM - 3C-21 WIRING HARNESS KIT 84-98423A4 For MCM 898R/228R/260R Stern Drive Engines INSTALLATION INSTRUCTIONS \ OTE: The fasteners, uhich are provided with this wiring harness. Ml ST BE used, as explained in the following instructions. when the harness is installed on MCM 470 Engines below Serial Xo. 5319156. Engines with Serial Xo. 5319156 and above already have the fasteners installed. This w iring harness ha.- Bl A standard color codes. Harness must be installed and secured with fasteners provided, as explained, following. 1. Remove (and discard) old wiring harness. Retain harness mounting plate anc 4 attaching screws and all terminal fasteners. 2. Install wiring harness receptacle in wiring harness bracket and secure with mounting plate and 4 screws (retained in Step 1). 12014 a - Sta-Strap b - Wiring Harness Figure 1. Wiring Harness Fastened to Flywheel Housing and Cylinder Head 3. Route wiring harness and install fasteners proviced with harness, as follows: a. Route section of harness (containing orange wire) to port side of engine, fasten harness (with sta-strap) to flvwheel housing. (Figure l) Remove %" screw from aft end of cvlinder head and install large J-clamp with 13/32" (10mmI attaching hole, as shown. Torque c - 3/8" Screw from Cylinder Head d - J-Clamp (13/32" Attaching Hole) screw to 120 lbs. in. (14 N.m). Route harness thru clamp and bend clamp shut. b. Remove :/+" screw from bottom of exhaust manifold and install j-clamp with 9/32" (7mm) attaching hole, as shown in Figure 2. Tighten screw securelv. Route harness thru clamp and bend clamp shut. c. Remove fore and aft rocker arm cover attaching screws (on starboard side of engine) and install J-clamps with 9/32" (7mm) attaching holes, as shown in Figure 3. Torque screw to 90 lbs. in. (10 N.m . Route harness thru clamps and bend clamps shut. 4. If engine it equipped with a fuse on the slave solenoid (port side of engine), remove (and discard) fuse. 5. Connect wiring harness leads to electrical components, as shown in Figure 4. Position insulator boots over terminals on wires so equipped, \pplv a coating of Liquid Neoprene to all terminal connections which are not protected by an insulator boot. 6. After making all necessary harness connections, reconnect positive (+) battery cable to positive battery terminal and negative (-) battery cable to negative battery terminal. a - Wiring Harness c - J-Clamp (9/32" b - Exhaust Manifold Attaching Hole) Figure 2. Wiring Harness Fastened to Manifold 12016 a - Rocker Arm Cover Attaching Screws c - Wiring b - J-Clamps (9/32" Attaching Hole) Harness Figure 3. Wiring Harness Fastened to Rocker Arm Cover 3E-22 - ELECTRICAL SYSTEM 90-95693 485 WIRING HARNESS KIT 84-98423A4 For MCM 898R/228R/260R Stern Drive Engines INSTALLATION INSTRUCTIONS XOTE: Fasteners, that are provided with this wiring harness. MI ST BE used, as explained in these instructions, when the harness is installed on the following engines: MCM 898 -Serial Xo. 5290812 and below MCM 228 -Serial Xo. 5307218-thru-530744T and Serial Xo. 5307210 and below MCM 260 -Serial Xo. 5375022 and below Engines u ith serial numbers above those listed already have the fasteners installed. a - J-Clamp (13/32" Attaching Ho e) D - 3/8" Screw (Provided in Kit) c - Wiring Harness Figure 2. Wiring Harness Fastened to Port Cylinder Head a - J-Clamp (13/32" Attaching Hole) b - Black Ground Wire c - Wiring Harness d - Flywheel Housing Figure 3. Wiring Harness Fastened to Flywheel Housing This wiring harness has B1A standard color codes. Harness must be installed and secured with fasteners provided, as explained, following. 1. Remove (and discard) old wiring harness. Retain harness mounting plate and 4 attaching screws and all terminal fasteners. 2. Install wiring harness receptacle in wiring harness bracket and secure with mounting plate and 4 screws (retained in Step 1). 3. Route wiring harness and install fasteners provided with harness, as follows: a - J-Clamp (9/32" Attaching Hole) b - Wiring Harness Figure 1. Wiring Harness Fastened to Starboard Rocker Arm Cover a. Remove upper front attaching screw from starboard rocker arm cover and install J-clamp with 9/32" (7mm) attaching hole, as shown in Figure 1. Torque screw to 48 in. lbs. (5.4 N.m). Route section of wiring harness (containing orarge wire) thru clamp and bend clamp shut. b. Install large J-clamp with 13/32" (10mm) attaching hole lo front of port cylinder head with screw (provided). (Figure 2) Tighten screw securelv. Route harness thru clamp and bend clamp shut. 3E-24 - ELECTRICAL SYSTEM 90-95693 485 c. Remove flywheel housing attaching nut (some engines may haveascrew) and instaii large .J-clamp with 13/32" attaching hole and biack ground wire, as shown in Figure3. Torque nut (or screw) to 30 ft. lbs. (41 N.m). Route harness thru clamp and bend clamp shut, if engine is equipped with fuse on starter solenoid, remove (and discard) fuse. Connect wiring harness leads to electrical components, as shown in Figure 4. being sure to complete the following: a. Position insuiaior boots over terminals on wires so equipped. b. Apply a coat of Liquid Neoprene to all terminal connections which are not protected by an insulator boot. c. Place heat shrink tubing (supplied with kit) over end of leads coming from alternator. Connect purple engine harness lead to purple (or white) alternator lead. Connect red-purple engine harness lead to red-purple (or red) alternator lead. Position heat shrink tubing over connections and heat with heat gun until secure. d. MCM engines, that are equipped with Delco single-wire alternators. DO NOT ( SK the purple and red-purple alternator leacs (items "a" and "b " in Figure 4). On these engines, the purple and red-purple leads MUST BE insulated and taped back to wiring harness, as follows: 1) Fold terminal on end of purple lead back against purple lead and secure with electrical tape. Insulate with at least 4 lavers of electrical tape completely covering the exposed metai of the terminal. 2) rold terminal on end ofred-purpie lead back against red-purple lead and secure with electrical tape. Insulate with at least 4 layers of eiectrical tape completely covering theexposed metal of the terminals. 3) Fold insulated purple and red-purple leads back against harness and secure with electrical tape. 6. After making all necessarv harness connections, reconnect positive (+) battery cable to positive battery terminal and negative (-) batterv cable to negative batterv terminal. Install and shrink sleeve (supplied with harness) over these quick disconnect terminals. Be sure that all exposed metal on terminals is covered. 'a - Red-Purple Wire - Connect to Alternator Red-Purple (or Red) Wire •b - Purple Wire - Connect to Alternator Purple (or White) Wire c - Black Wire - Connect to Alternator Ground Terminal d - Orange Wire - Connect to Alternator ("BAT") Output Terminal e - Insulator Boot f - Purple Wire - on MCM 898, Connect to Terminal on Choke Housing Assembly: on All Other Models, Tape Back to Harness and Insulate with at Least 4 Layers of Electrical Tape (Completely Covering Exposed Metal of Terminal) g - Tan Wire - Connect to Water Temperature Sender Near Thermostat Housing on Starboard Side of Intake Manifold h - Red-Purple Wire - Connect to Circuit Breaker Terminal Closest to Receptacle i - Brown-White Wire - Connect to Insulated Terminal on Trim Position Sender Terminal Block j - Light 3lue Wire - Connect to Oil Pressure Sender on Aft End of Engine k - Purple-Yellow and Purple Wires - Connect to Positive (->-) Terminal on Ignition Coil I - Gray Wires - Connect to Negative (-) Terminal on Ignition Coil m - Receptacle n - Red Wire - Connect to Circuit Breaker Terminal Furthest away from Receptacle o - Black Wire - Connect to Shift Interrupter Switch Terminal Block Mounting Screw p - Gray Wire - Connect to Shift Interrupter Switch Terminal Block q - Black Wire - Connect to Flywheel Housing Attaching Screw on Starboard Side of Engine r - Purple-Yellow Wire - Connect to "I" Terminal on Slave Solenoid s - Yellow-Red Wire - Connect to "S" Terminal on Slave Solenoid t - Black Wire - Connect to Slave Solenoid Mounting Bracket u - Yellow-Red Wire - Connect to One Large Terminal on Slave Solenoid v - Red-Purple Wire - Connect to Other Large Terminal on Slave Solenoid w - Red-Yellow Wire - Connect to "S" Terminal on Starter Mounted Solenoid x - Red Wire - Ccnnect to Large Terminal on Starter Mounted Solenoid Figure 4. Wiring Harness (84-86676A2) Electrical Connections 90-95693 485 ELECTRICAL. SYSTEM - 3C-25 WIRING HARNESS KIT 84-98423A4 For MCM 898R/228R/260R Stern Drive Engines INSTALLATION INSTRUCTIONS Install heal shrink tubing over the quick disconnect terminals at alternator. Be sure that all exposed metal on terminals is covered. Position insulator boots over terminals on wires so equipped. Apply a chin coat of Quicksilver Liquid Neoprene (92-25711) to all terminal connections which are not protected by an insulator boot. On MCM 228R-260R models the purple and black electric- following: choke leads MUST BE individually insulated with at least 4 • Be sure that all J' -clamps, which secure wiring harness, layers of electrical tape (completely covering exposed are bent shut. metal of terminal) then: taped back against harness. Install wiring harness, as shown, being sure to observe the 3E-26 - ELECTRICAL SYSTEM 90-95693 485 WIRING HARNESS KIT 84-86683A2 For MCM 330 Stern Drive Engine INSTALLATION INSTRUCTIONS \OTE: The fasteners, which are provided with this wiring harness. Ml ST BE used, as explained in the following instructions. when the harness is installed on MCM 330 Engines below Serial \o. 5354658. Engines with Serial \o. 5354658 and above already have the fasteners installed. This wiring harness has BIA standard color codes. Harness musl be installed and secured with fasteners provided, as explained, following. 1. Remove (and discard) old wiring harness. Retain harness mounting plate and 4 attaching screws and all terminal fasteners. 2. Install wiring harness receptacle in wiring harness bracket and secure with mounting plate and 4 screws (retained in Step 1). 3. Route wiring harness and install fasteners provided with harness, as follows: a. Remove screws from rocker arm cover (on port side of engine) and install J-clamps with 9/32" (7mm) attaching hole, as shown in Figure 1. Torque screws to 48 in. lbs. (5.4 N.m). Route long section of harness thru clamps and bend clamps shut. b. Remove bottom attaching screw from alternator bracket and install J-clamp with 13/32" (10mm) attaching hole, a- shown in Figure 2. Torque screw to 25 ft. lbs. (34 N.m). Route end of harness thru clamp to alternator and bend clamp shut. a - J-Clamps (9/32" Attaching Hole) b - Wiring Harness Figure 1. Wiring Harness Fastened to Port Rocker Arm Cover 90-95693 485 a - J-Clamp (13/32" Attaching Hole) b - Wiring Harness c - Alternator Bracket Figure 2. Wiring Harness Fastened to Alternator Bracket c. Route short section of wiring harness (wires a . b and "c" in Figure 3) over to starter. 4. If engine is equipped with a fuse on starter solenoid, remove (and discard) fuse. 5. Connect wiring harness leads to electrical components. a> shown in Figure 3. being sure to complete the following: a. Position insulator boots over terminals on wires so equipped. b. Applvacoat of Liquid Neoprene to all terminal connections which are not protected by an insulator boot. c. Place heat shrink tubing (supplied with kil) over end of leads coming from alternator. (Connect purple engine harness lead to purple (or white) allernalor lead. Connect red-purple engine harness lead to red-purple (or red) alternator lead. Position heat shrink tubing over connections and heat with heat gut until secure. d. MCM engines, that are equipped with Delco single-wire alternators, do not use the purple and red-purple alternator leads (items "V" and "t " in Figure 3). On these engines, the purple and red-purple leads Ml ST Bl\ insulated and taped back to wiring harness, a? follows: 1) Fold terminal on end of purple lead back against purple lead and secure with electrical tape. Insulate with at least 4 lavers of electrical tape complete!) covering the exposed metal of the terminal. 2) F old terminal on end of red-purple lead back against red-purple lead and secure with electrical tape. Insulate with at least 1 layers of electrical tape compielelv covering the exposed metal of the terminals. ELECTRICAL SYSTEM - 3E-27 3) Fold insulated purple and red-purple leads back against harness and secure with electrical tape. 6. After makingall necessarv harness connections, reconnect positive (+) battery cable to positive battery terminal and negative (-) battery cable to negative battery terminal. a - Yellow-Red Wire - Connect to "S" Terminal on Starter Mounted Solenoid b - Purple-Yellow Wire - Connect to "R" Terminal on Starter Mounted Solenoid c - Red Wire - Connect to Large Terminal on Starter Mounted Solenoid d - Black Wire - Connect to Flywheel Housing Attaching Screw on Starboard S de of Engine e - Receptacle f - Brown-White Wires - Connect to Insulated Terminal on Trim Position Sender Terminal Block g - Red-Purple Wire - Connect to Upper Term nal on Circuit Breaker h - Insulator Boot i - Red Wire - Connect to Lower Terminal on Circuit Breaker j - Red-Purple Wire - Connect to One Large Terminal on Slave Solenoid k - Yellow-Red Wire - Connect to Other Large Terminal on Slave Solenoid I - Yellow-Red Wire - Connect to Small Lower Terminal on Slave Solenoid m - Light Blue Wire - Connect to Oil Pressure Sender on Port Side of Engine n - Gray Wire - Connect to Negative (-) Terminal on Ignition Coil o - Purple-Yellow and Purple Wires - Connect to Positive (+) Terminal on Ignition Coil p - Tan Wire - Connect to Water Temperature Sender on Starboard Side of Intake Manifold near Thermostat Housing q - Black Wire - Connect to Alternator Ground Terminal r - Orange Wire - Connect to Alternator Output ("BAT") Terminal "s - Purple Wire - Connect to Alternator Purple (or White) Wire *t - Red-Purple Wire - Connect to Alternator Red-Purple (or Red) Wires "Install and shrink sleeves (supplied with harness) over these quick disconnect terminals. Be sure that all exposed metal on the terminals is covered. Figure 3. Wiring Harness (84-86683A2) Electrical Connections 3C-28 - ELECTRICAL SYSTEM 90-95693 485 WIRING HARNESS KIT 84-86677A2 For MIE 228/255/330 Inboard Engines INSTALLATION INSTRUCTIONS NOTE: The fasteners. which are provided with this wiring harness. Ml ST BE used, as explained in the following instructions. when the harness is installed on the following engines: \11E228 -Serial No. 5263525 and below MIE 255 • Serial No. 5325249 and below MIE330 [ R.H. (Opposite) Rotation] -5300499 and below MIE330 j L.H. (Standard) Rotation] -5369093 andbelou Engines with serial numbers above those listed, already have the fasteners installed. 1. Remove (and discard) old wiring harness. Retain harness mounting plate and 4 attaching screws and all terminal fasteners. a - J-Clamp (9/32" Attaching Hole) b - Wiring Harness c- Rocker Arm Cover Screw Figure 2. Wiring Harness Fastened to Port Rocker Arm Cover 2) Remove rear attaching screw from port rocker arm cover and install J-clamp with 9/ 32" (7mm) attaching hole, as shown in Figure 2. Torque screw lo 48 in. lbs. (5.4 N.m). Route harness thru clamp and bend clamp shut. 3) Install smaller J-clamp with 13/32" (10mm) attaching hole to front of port cylinder head with screw (provided), as shown in Figure 3. Tighten screw securelv. Route harness thru clamp and bend clamp shut. a - Oil Filter Mounting Bracket Screw b - J-Clamp (13/32" Attaching Hole) c - Wiring Harness Figure 1. Wiring Harness Fastened to Oil Filter Bracket 2. In-ilall wiring harness receptacle in wiring harness bracket and secure with mounting plate and 4 screw;, (retained in Step 1). 3. Route wiring harness and install fasteners provided with harness, as follows: a. MIK 228/255 Engine 1) Remove oil filter mounting bracket screw and install large J-clamp with 13/32" (10mm) attaching a - J-Clamp (13/32" Attaching Hole) hole, as shown in Figure 1. Torque screw secureh . b - 3/8" Fastening Screw (Provided in Kit) c-Wiring Harness Route long section of harness thru clamp and bend Figure 3. Wiring Harness Fastened to Port Cylinder clamp shut. Head 90-95593 485 ELECTRICAL SYSTEM - 3E-29 \ OTE: Remainder of fasteners are not required for MerCruiser 228/255 Inboard Engines. b. MIE 330 Engine 1) Remove oil filter mounting bracket screw anrl install large J-clamp with 13/32" (10mm) attaching hole, as shown in Figure 1. Tighten screw securelv. Route long section of harness thru clamp and bend clamp shut. 2) Remove attaching screw from port rocker arm valve cover and install J-clamp with 9/32" (7mm) attaching hole, as shown in Figure 4. Torque screw to 48 in. lbs. (5.4 N.m). Route harness thru clamp and bend clamp shut. 3) Secure wiring harness to water inlet hose with stastrap (provided), as shown in Figure 5. XOTE: Remainder of fasteners are not required for MIE 330 Engine. 4. If engine is equipped with a fuse on starter solenoid, remove (and discard) fuse. 5. Connect wiring harness leads to electrical components, as shown in Figure 6. being sure to complete the following: a. Position insulator boots over terminals on wires so equipped. b. Applv a coat of Liquid Neoprene to all terminal connections which are not protected by an insulator boot. c. Place heat shrink tubing (supplied with kit) over end of leads coming from alternator. Connect purple engine harness lead to purple (or white) alternator lead. Connect red-purple engine harness lead to red-purple (or red) alternator lead. Position heat shrink tubing over connections and heat with heat gun until secure. d. MerCruiser engines, that are equipped with Delco single-wire alternators, DO NOT use the purple and red-purple alternator leads (items "u " and v in Figure 6). On these engines, the purple and red-purple leads MUST BE insulated and taped back to wiring harness, as follows: 1) Fold terminal on end of purple lead back against purple lead and secure with electrical tape. Insulate with at least 4 layers of electrical tape completelv covering the exposed metal of the terminal. 2) Fold terminal on end of red-purple lead back against red-purple lead and secure with electrical tape. Insulate with at least 4 layers of electrical tape completely covering the exposed metal of the terminals. 3) Fold insulated purple and red-purple leads back against harness and secure with electrical tape. a - Inlet Water Hose b - Sta-Strap c - Wiring Harness Figure 5. Wiring Harness Fastened to Water Inlet Hose a - J-Clamp (9/32" Attaching Hole) b - Wiring Harness c - Rocker Arm Cover Screw Figure 4. Wiring Harness Fastened to Port Rocker Arm Cover 3E-30 - ELECTRICAL SYSTEM SC-S5SS3 46s a - Insulator Boots b - Red Wire - Connect to Lower Terminal on Circuit Breaker c - Red-Purple Wire - Connect to Upper Termina on Circuit Breaker d - Yellow-Red Wire - Connect to One of the Large Terminals on Slave Solenoid e - Red-Purple Wire - Connect to Remaining Large Terminal on Slave Solenoid f - Black-Yellow Wire - Connect to One Small Terminal on Slave Solenoid g - Yellow-Red Wire - Connect to Other Small Terminal on Slave Solenoid h - Receptacle i - Black Wire - Connect to Flywheel Housing Attaching Stud on Starboard Side o! Engine (Some Engines May Have a Screw): j - Torque Nut or Screw to 20 Ft. Lbs. (27 N.m) k - Black-Yellow Wire - Connect to One of the Terminals on Neutral Safety Switch I - Yellow-Red Wire - Connect to "S" Terminal on Starter Mounted Solenoid m - Red Wire - Connect to Large Terminal on Starter Mounted Solenoid n - Purple-Yellow Wire - Connect to "R" Terminal on Starter Mounted Solenoid o - Brown-White Wire - Taped to Harness and Insulated p - Light Blue Wire - Connect to Oil Pressure Sender on Aft End of Engine near Circuit Breaker on MIE 228/255 or Port Side of Engine on MIE 330 (on MIE 330, the Sta-Strap, That Secures Wire to Harness, Must Be Removed to Extend Wire) q - Sta-Strap r - Gray Wire - Connect to Negative (-) Terminal on Ignition Coil s - Purple-Yellow and Purple Wire - Connect to Positive (t) Terminal on Ignition Coil t - Tan Wire - Connect to Water Temperature Sender on Starboard Side of Intake Manifold Near Thermostat Housing 'u - Red-Purple Wire - Connect to Alternator Red-Purple (or Red) Wire *v - Purple Wirew - Orange Wirex - Black Wire - Connect to Alternator Purple (or White) Wire - Connect to Alternator Output (' BAT") Terminal Connect to Alternator Ground Terminal *Install and shrink sleeves (supplied with harness) over these quick disconnect terminals. Be sure that all exposed metal on the terminals is covered. Figure 6. Wiring Harness (84-86677A2) Electrical Connections 90-95693 485 ELECTRICAL SYSTEM - 3E-31 - SECTION 3 - ELECTRICAL SYSTEM PART F - WIRING DIAGRAMS wiring harness INDEX Wiring Colors for MerCruiser MCM 120/140 Engines (Ammeter Circuit) MCM 120/140 Engines (Battery Meter Circuit) MCM 120R/140R Engines (Battery Meter Circuit) MCM 165 Engine (Ammeter Circuit) MCM 470 Engine (Ammeter Circuit) MCM 470 Engine (Battery Meter Circuit) MCM 470R Engine (Battery Meter Circuit) MCM 485 Engine (Ammeter Circuit) MCM 485 Engine (Battery Meter Circuit) MCM 488R Engine (Battery Meter Circuit) MCM 898 Engine (Ammeter Circuit) MCM 898 Engine (Battery Meter Circuit) MCM 898R Engine (Battery Meter Circuit) MCM 228/260 Engines (Ammeter Circuit) MCM 228/260 Engines (Battery Meter Circuit) MCM 228R/260R Engines (Battery Meter Circuit) MCM 330 Engine (Ammeter Circuit) MCM 330 (B-W) Engine (Battery Meter Circuit) MCM 370/400TRS Engines (Ammeter Circuit) MCM 400 Cyclone/440 Cyclone/460 Cyclone/ 475 Turbo Engines (Ammeter Circuit) MIE 470 Inboard Engine (Ammeter Circuit) MIE 228/255 Inboard Engines (Ammeter Circuit) MIE 230/260 Inboard Engines (Battery Meter Circuit) MIE 330 Inboard Engine (Ammeter Circuit) MIE 340 Inboard Engine (Battery Meter Circuit) Instrument Wiring Diagram (Ammeter Circuit) Instrument Wiring Diagram (Battery Meter Circuit) MCM 370/400TRS Instrument Wiring Diagram (Ammeter Circuit) Harness with Connector Plug (Battery Meter Circuit) Dual Station Wiring DiagramsBattery Meter GaugesAmmeter GaugesWater Temperature GaugeMerCruiser 470/485 Temperature Gauge Resistor Kit Oil Pressure Gauge Clocks Cruiselogs Fuel Gauge and Sender Key Switches Audio Warning System Page 3F-1 3F-2 to 3F-5 3F-6 3F-7 to 3F-10 3F-11 to 3F-14 3F-15 to 3F-17 3F-18 3F-19 to 3F-21 3F-22 3F-23 3F-24 to 3F-26 3F-27 to 3F-30 3F-31 3F-32 to 3F-34 3F-35 to 3F-38 3F-39 3F-40 to 3F-42 3F-43 to 3F-46 3F-47 to 3F-49 3F-50 3F-51 3F-52 3F-53 to 3F-55 3F-56 to 3F-58 3F-59 to 3F-61 3F-62 to 3F-64 3F-65 to 3F-67 3F-68 3F-69 3F-70 3F-71 to 3F-76 3F-77 3F-78 3F-79 3F-79 3F-80 3F-80 3F-81 3F-82 3F-83 to 3F-84 3F-85 WIRING COLORS for MERCRUISER (Cross-Reference Chart) (In Alphabetical Order of Pre BIA Colors) Pre BIA Color Code BIA Color Code Where Used Black Black All Grounds Black Brown Reference Electrode MerCathode Black Orange Anode Electrode MerCathode Blue Lt. Blue/White Trim " Up" Switch Brown Gray Tachometer Signal Green Green/White Trim " Down" Switch Green Tan Water Temp. Sender to Gauge Orange Lt. Blue Oil Pressure Sender (10 Gauge) Pink Pink Fuel Gauge Sender to Gauge Purple Brown/White Trim Sender to Trim Gauge Purple Purple/White Trim " Trailer" Switch Red Red Unprotected Wires from Battery Red Red/Purple Protected (Fused) Wires from Battery Red Red/Purple Protected (+12V) to Trim Panel Red/White Orange Alternator Output Tan Purple/Yellow Ballast Bypass White Purple Ignition Switch (+12V) Yellow Yellow Starter Solenoid to Starter Motor (MCM/MIE 470/MCM 485) Yellow Yellow/Red Starter Switch to Starter Solenoid to Neutral Start Switch SO-95693 485 ELECTRICAL SYSTEM -3F-1 MCM 120/140 Engine Wiring Diagram Pre BIA Color Code with 55 Amp Fuse at Starter Motor (Red Wire) (Ammeter Circuit) 90-95693 485 3C-2 - ELECTRICAL SYSTEM MCM 120/140 Engine Wiring Diagram Pre BIA Color Code with 90 Amp Fuse at Starter Motor (Red Wire) (Ammeter Circuit) 90-95693 485 ELECTRICAL. SYSTEM - 3C-3 r MCM 120/140 Engine Wiring Diagram BIA Color Code with 90 Amp Fuse at Starter Motor (Red Wire) (Ammeter Circuit) 3C-4 - ELECTRICAL SYSTEM 90-95693 1-888 90-95693 485 90-95693 485 3C-6 - ELECTRICAL SYSTEM 183-H MCM 330 (B-W) Engine Wiring Diagram (Battery Meter Circuit) 90-95693 485 ELECTRICAL SYSTEM 3F- 7 MCM 120R/140R Engine Wiring Diagram MCM 120R/140R Engine Wiring Diagram with 90 Amp Fuse at Starter Motor (Orange Wire) Delco Alternator (Battery Meter Circuit) 90-95693 1-888 3C-8 - ELECTRICAL SYSTEM MCM 120R/140R Engine Wiring Diagram with 90 Amp Fuse at Starter Motor (Orange Wire) Mando Alternator (Battery Meter Circuit) 90-95693 485 ELECTRICAL. SYSTEM - 3C-9 Mando Alternator (Battery Meter Circuit) 90-95693 485 3C-10 - ELECTRICAL SYSTEM MCM 228/260 Engine Wiring Diagram Pre BIA Color Code with 55 Amp Fuse at Starter Motor (Red Wire) (Ammeter Circuit) ELECTRICAL SYSTEM - 3F-11 MCM 165 Engine Wiring Diagram Pre BIA Color Code with 90 Amp Fuse at Starter Motor (Red Wire) (Ammeter Circuit) 3F-12 - ELECTRICAL SYSTEM MCM 165 Engine Wiring Diagram BIA Color Code with 90 Amp Fuse at Starter Motor (Red Wire) (Ammeter Circuit) 90-95693 485 ELECTRICAL. SYSTEM - 3C-13 MCM 165 Engine Wiring Diagram BIA Color Code without 90 Amp Fuse at Starter Motor (Red Wire) (Ammeter Circuit) 3C-14 - ELECTRICAL SYSTEM 90-95693 1-888 MCM 330 Engine Wiring Diagram (Electric Shift) Pre BIA Color Code with 55 AmpFuse at Starter Motor (Red Wire) (Ammeter Circuit) 90-95693 485 ELECTRICAL SYSTEM - 3F-15 MCM 228/255 Inboard Engine Wiring Diagram Pre BIA Color Code with 90 Amp Fuse at Starter Motor (Red Wire) (Ammeter Circuit) 3F-16 - ELECTRICAL SYSTEM 90-95693 485 \OTE 1: Remove this wire if ammeter is to be used. Jumper must be left connected if Battery Meter is used. MCM 470 Engine Wiring Diagram BIA Color Code (Ammeter Circuit) 90-95693 485 ELECTRICAL. SYSTEM - 3C-17 MCM 470 Engine Wiring Diagram BIA Color Code (Battery Meter Circuit) 90-95693 485 3F-18 - ELECTRICAL SYSTEM MCM 470R Engine Wiring Diagram Delco Starter Motor (Battery Meter Circuit) 90-95693 485 ELECTRICAL SYSTEM - 3F-19 MCM 470R Engine Wiring Diagramwith 90 Amp Fuse at Delco Starter Motor (Orange Wire) (Battery Meter Circuit) 192-hr r 3C-20 - ELECTRICAL SYSTEM 90-95693 1-888 MCM 470R Engine Wiring Diagramwithout 90 Amp Fuse at Delco Starter Motor (Orange Wire) (Battery Meter Circuit) 192-HRR 90-95693 485 ELECTRICAL. SYSTEM - 3C-21 NOTE 1: Remove this u ire if ammeter is to be used. Jumper must be left connected if Battery Meter is used. MCM 485 Engine Wiring Diagram (Ammeter Circuit) 90-95693 485 3F-22 - ELECTRICAL SYSTEM MCM 330 (B-W) Engine Wiring Diagram (Battery Meter Circuit) 90-95693 485 ELECTRICAL SYSTEM - 3F-23 192-H MIE 340 Inboard Engine Wiring Diagram (Battery Meter Circuit) 3F-24 ELECTRICAL SYSTEM 90-95693 485 MCM 488R Engine Wiring Diagram with 90 Amp Fuse at Starter Motor (Orange Wire) (Battery Meter Circuit) 90-95693 485 ELECTRICAL SYSTEM - 3F-25 193-h3 MCM 488R Engine Wiring Diagram without 90 Amp Fuse at Starter Motor (Orange Wire) (Battery Meter Circuit) 90-95693 485 3F-26 - ELECTRICAL SYSTEM MCM 330 Engine Wiring Diagram (Electric Shift) Pre BIA Color Code with 55 AmpFuse at Starter Motor (Red Wire) (Ammeter Circuit) 90-95693 485 ELECTRICAL SYSTEM - 3F-27 MCM 228/260 Engine Wiring Diagram Pre BIA Color Code with 90 Amp Fuse at Starter Motor (Red Wire) (Ammeter Circuit) 3F-28 - ELECTRICAL SYSTEM 90-95693 485 MCM 330 Engine Wiring Diagram (Electric Shift) Pre BIA Color Code with 55 AmpFuse at Starter Motor (Red Wire) (Ammeter Circuit) 90-95693 485 ELECTRICAL SYSTEM - 3F-29 MCM 898 Engine Wiring Diagram BIA Color Code without 90 Amp Fuse at Starter Motor (Red Wire) (Ammeter Circuit) 3C-30 - ELECTRICAL SYSTEM 90-95693 1-888 90-95693 485 ELECTRICAL. SYSTEM - 3C-31 347-H 347-H MIE 340 Inboard Engine Wiring Diagram (Battery Meter Circuit) 90-95693 485 3F-32 - ELECTRICAL SYSTEM with 347-h with 347-h 90-95693 485 ELECTRICAL. SYSTEM - 3C-33 347 HR MCM 898R Engine Wiring Diagram without 90 Amp Fuse at Starter Motor (Orange Wire) (Battery Meter Circuit) 3F-34 - ELECTRICAL SYSTEM 90-95693 485 MCM 228/260 Engine Wiring Diagram Pre BIA Color Code with 55 Amp Fuse at Starter Motor (Red Wire) (Ammeter Circuit) ELECTRICAL SYSTEM - 3F-35 MCM 228/260 Engine Wiring Diagram Pre BIA Color Code with 90 Amp Fuse at Starter Motor (Red Wire) (Ammeter Circuit) 3F-36 - ELECTRICAL SYSTEM 90-95693 485 MCM 330 Engine Wiring Diagram (Electric Shift) Pre BIA Color Code with 55 AmpFuse at Starter Motor (Red Wire) (Ammeter Circuit) 90-95693 485 ELECTRICAL SYSTEM - 3F-37 MCM 228/260 Engine Wiring Diagram BIA Color Code without 90 Amp Fuse at Starter Motor (Red Wire) (Ammeter Circuit) 3F-38 - ELECTRICAL SYSTEM 90-95693 485 MCM 228/260 Engine Wiring Diagram (Battery Meter Circuit) 90-95693 485 ELECTRICAL. SYSTEM - 3C-39 MIE 340 Inboard Engine Wiring Diagram (Battery Meter Circuit) 3F-40 - ELECTRICAL SYSTEM 90-95693 485 with 90 Amp Fuse at Starter Motor (Orange Wire) (Battery Meter Circuit) 335 HR 90-95693 485 ELECTRICAL. SYSTEM - 3C-41 MCM 228R/260R Engine Wiring Diagram without 90 Amp Fuse at Starter Motor (Orange Wire) (Battery Meter Circuit) 3C-42 - ELECTRICAL SYSTEM 90-95693 1-888 MCM 330 Engine Wiring Diagram (Electric Shift) Pre BIA Color Code with 55 AmpFuse at Starter Motor (Red Wire) (Ammeter Circuit) ELECTRICAL SYSTEM - 3F-43 90-95693 485 MCM 228/255 Inboard Engine Wiring Diagram Pre BIA Color Code with 90 Amp Fuse at Starter Motor (Red Wire) (Ammeter Circuit) 3F-44 - ELECTRICAL SYSTEM 90-95693 485 MCM 330 Engine Wiring Diagram (Electric Shift) Pre BIA Color Code with 55 AmpFuse at Starter Motor (Red Wire) (Ammeter Circuit) 90-95693 485 ELECTRICAL SYSTEM - 3F-45 90-95693 1-888 3C-46 - ELECTRICAL SYSTEM MCM 330 (B-W) Engine Wiring Diagram (Battery Meter Circuit) ELECTRICAL SYSTEM - 3F-47 90-95693 485 3C-48 - ELECTRICAL SYSTEM 90-95693 1-888 90-95693 485 ELECTRICAL. SYSTEM - 3C-49 512-11 MCM 370/400TRS Engine Wiring Diagram BIA Color Code (Ammeter Circuit) 3F-50 ELECTRICAL SYSTEM 90-95693 485 Hi-Performance MCM 400 Cyclone. 440 Cyclone, 460 Cyclone and 475 Turbo Engine Wiring Diagram BIA Color Code (Ammeter Circuit) 90-95693 485 ELECTRICAL SYSTEM - 3F-51 \OTE 1: Remote this uire if ammeter is to be used. Jumper must be left connected if Battery Meter is used. MIE 470 Inboard Engine Wiring Diagram (Ammeter Circuit) 3F-52 - ELECTRICAL SYSTEM MCM 330 Engine Wiring Diagram (Electric Shift) Pre BIA Color Code with 55 AmpFuse at Starter Motor (Red Wire) (Ammeter Circuit) 90-95693 485 ELECTRICAL SYSTEM - 3F-53 MCM 228/255 Inboard Engine Wiring Diagram Pre BIA Color Code with 90 Amp Fuse at Starter Motor (Red Wire) (Ammeter Circuit) 3F-54 - ELECTRICAL SYSTEM 90-95693 485 MIE 228/255 Inboard Engine Wiring Diagram BIA Color Code with 90 Amp Fuse at Starter Motor (Red Wire) (Ammeter Circuit) 90-95693 485 ELECTRICAL SYSTEM - 3F-55 MIE 230/260 Inboard Engine Wiring Diagram (Battery Meter Circuit) 3C-56 - ELECTRICAL SYSTEM 90-95693 1-888 ELECTRICAL SYSTEM - 3F-57 90-95693 485 90-95693 1-888 3C-58 - ELECTRICAL SYSTEM MIE 330 Inboard Engine Wiring Diagram Pre BIA Color Code with 55 Amp Fuse at Starter Motor (Red Wire) (Ammeter Circuit) ELECTRICAL SYSTEM - 3F-59 90-95693 485 MCM 228/255 Inboard Engine Wiring Diagram Pre BIA Color Code with 90 Amp Fuse at Starter Motor (Red Wire) (Ammeter Circuit) 90-95693 485 3F-60 - ELECTRICAL SYSTEM A A MIE 330 Inboard Engine Wiring Diagram BIA Color Code without 90 Amp Fuse at Starter Motor (Red Wire) (Ammeter Circuit) 90-95693 485 ELECTRICAL SYSTEM - 3F-61 MIE 340 Inboard Engine Wiring Diagram (Battery Meter Circuit) 3F-62 - ELECTRICAL SYSTEM 90-95693 485 3^2-H 3^2-H ELECTRICAL. SYSTEM- 3C-427 90-95693 485 3C-64 - ELECTRICAL SYSTEM 90-95693 1-888 y Instrument Wiring Diagram with Ammeter Circuit Pre BIA Color Code ELECTRICAL SYSTEM - 3F-65 90-95693 485 Instrument Wiring Diagram with Ammeter Circuit (Early Style) BIA Coior Code 90-95693 485 3F-66 - ELECTRICAL SYSTEM Instrument Wiring Diagram with Ammeter Circuit (Later Style) BIA Color Code 90-95693 485 ELECTRICAL SYSTEM - 3F-67 Instrumentation Wiring Diagram with Battery Meter Circuit 90-95693 1-888 3C-68 - ELECTRICAL SYSTEM MCM 370/400TRS Instrument Wiring Diagram (Typical Gauges Shown) 90-95693 485 ELECTRICAL SYSTEM - 3F-69 NOTES: 1. If a neutral safety switch is incorporated in the re3. If installing on boat, that is equipped with Mermote control connect yellow/red wires as shown. If Cruiser Stern Drive, the cluster oj wires containing engine is equipped with a neutral safety switch on brown/white, black and purple wires is intended for the engine, connect yellow/ red ignition switch wire use with optional Quicksilver Power Trim gauge as directly to yellow/ red wiring harness wire with shown. If installing on MerCruiser Inboard, this screw, nut and sleeve. same cluster of wires can be either taped back to harness, or used with optional Quicksilver Fuel gauge. [If optional fuel gauge is used, connect same cluster of wires to fuel gauge. Then, connect brown/ white wire (which is taped back to engine wiring harness) to fuel sender.] 4. If a separate switch for instrument lights is desired, metal link may be removed from gauges and light switch power lead can be connected directly to light 2. An accessory fuse panel may be connected at this bulb socket. Refer to instructions which accompany point. Load may not exceed 35 amps. instruments. Wiring Diagram for Harness with Connector Plug (Battery Meter Circuit) 3C-70 - ELECTRICAL SYSTEM 90-95693 1-888 8 8 Dual Station Wiring Diagram Using a Neutral Safety Switch in Both Remote Controls (Ammeter Circuit) 90-95693 485 ELECTRICAL SYSTEM - 3F-71 Dual Station Wiring Diagram Using a Neutral Safety Switch in Both Remote Controls * (Battery Meter Circuit) 90-956S3 485 3F-72 - ELECTRICAL SYSTEM Dual Station Wiring Diagram Using a Neutral Safety Switch in Only One Remote Control (Ammeter Circuit) ELECTRICAL SYSTEM - 3F-73 90-95693 485 90-95693 485 3F-74 - ELECTRICAL SYSTEM Dual Station Wiring Diagram When Neutral Safety Switch is in Engine Wiring Harness (Ammeter Circuit) 90-95693 485 ELECTRICAL SYSTEM - 3F-75 Dual Station Wiring Diagram When Neutral Safety Switch is in Engine Wiring Harness (Battery Meter Circuit) 90-95693 485 3F-76 - ELECTRICAL SYSTEM Later Style Later Style a - Lamp Mounting Hole b- Gauge Mounting Studs c - Terminal Not Used d - Purple (or White) Jumper Wire from This Terminal tol(or+) Terminal on Water Temperature or Oil Pressure Guage e - Black Jumper Wire from This Terminal to Ground Terminal on Water Temperature or Oil Pressure Gauge Battery Meter Gauges 90-95693 485 ELECTRICAL. SYSTEM - 3C-77 a. While Wire Jumper (Supplied in Kit) That a. Purple Wire a. To 12-Volt Switched Terminal on Adjacent Is Connected to Gauge or to Accessory Nearest 12-Volt Supply Side of Ignition Switch b c. Red with White Stripe Wire Red Wire b. Orange Wire c. Red with Purple Stripe b. To "Batt" Side of Alternator c. To Battery or to "Batt" Side of Starter Wire Solenoid d Black Wire d. Black Wire d. To Ground Ammeter Gauges 90-95693 485 3F-78 - ELECTRICAL SYSTEM Pre BIA Color Code BIA Color Code Leads to — 3. Black Wire a Black a. Ground b White Wire b. Purple b Switched 12-Volt Terminal e. Green Wire c. Tan c Sender Lead If So Equipped 90-95693 485 ELECTRICAL. SYSTEM - 3C-79 Earlier Model MerCruiser Color Code BIA Color Code Leads to — (a) Black Wire (b) White Wire (c) Orange Wire (a) Black (b) Purple (c) Light Blue (a) Ground (b) Switched 12-Volt Terminal (c) Sender Lead Clocks 3C-80 - ELECTRICAL SYSTEM 90-95693 1-888 90-95693 485 ELECTRICAL SYSTEM - 3F-81 Fuel Gauge and Sender 3C-82 - ELECTRICAL SYSTEM 90-95693 1-888 Key Switch Installation when Using Ammeter and Pre BIA Color-Coded Wiring Harness White Jumper Key Switch Installation when Using Battery Meter and Pre BIA Color-Coded Wiring Harness NOTE I. If engine is equipped with a neutral safety switch (on the engine or transmission J. connect yellou red ignition switch wire directly to yellow/red wiring harness wire with screw, nut and sleerc. 1 neutral safety switch MUST BE used in starting circuit to prevent accidental starting of engine when in gear. 2. On MerCruiser 470 and485 models. DO XOT connect red/ white wire. Tape hack and insulate ring terminal with at least 4 layers of electrical tape. 90-95693 485 ELECTRICAL. SYSTEM - 3C-83 Key Switch Installation when Using Ammeter and BIA Color-Coded Wiring Harness BIA Color-Coded Wiring Harness NOTE 1. If engine is equipped with a neutral safety switch (on the engine or transmission), connect yellow/red ignition switch wire directly to yellow/red wiring harness wire with screw, nut and sleeve. A neutral safety switch MUST BE used in starting circuit to prevent accidental starting of engine when in gear. 2. On MerCruiser 4 70 and 485 models. DO NOT connect orange wire. Tape back and insulate ring terminal with at least 4 layers of electrical tape. 3C-84 - ELECTRICAL SYSTEM 90-95693 1-888 SECTION 4 - FUEL SYSTEM PART A - FUEL DELIVERY SYSTEM and FUEL PUMPS INDEX Page Identification 4A-1 Replacement Parts Warning 4A-2 Torque Specifications 4A-2 Tools/Lubricants/Sealants 4A-3 Specifications 4A-3 Precautions 4A-4 Fuel Delivery System 4A-4 Recommendations 4A-4 Description 4A-4 Water Separating Fuel Filter 4A-5 Replacement 4A-6 Fuel Pump Fuel Filter Replacement 4A-7 Sight Tube or Sight Glass 4A-8 Inspection 4A-8 Sight Glass Replacement 4A-9 Testing Fuel Pump 4A-9 CARTER PUMP (LOW VOLUME) 4A-10 Removal 4A-10 Disassembly 4A-10 Cleaning and Inspection 4A-11 Reassembly 4A-11 Installation 4A-11 CARTER PUMP (HIGH VOLUME) 4A-11 Replacement 4A-11 AC PUMP (DUAL DIAPHRAGM) 4A-12 Replacement 4A-12 AIRTEX PUMP 4A-12 Replacement 4A-12 High Flow Fuel Pump Kit (42725A2) 4A-13 IDENTIFICATION 17101 18395 Figure 1. Carter Pump (Low Volume) Figure 2. Carter Pump (High Volume) 18396 18394 Figure 3. AC Pump (Dual Diaphragm) Figure 4. Airtex Pump 90-95693 485 EXHAUST SYSTEM- 5A-453 REPLACEMENT PARTS WARNING Electrical, ignition and fuel system components on your MerCruiser are designed and manufactured to comply with U.S. Coast Guard Rules and Regulations to minimize risks of fire and explosion. Use of replacement electrical, ignition or fuel system components, which do not comply with these rules and regulations, could result in a fireorexplosion hazard and should beavoided. TORQUE SPECIFICATIONS Fastene FasteneFastene r rr Locatio LocatioLocatio n nn Carter (Low Volume) Carter (High Volume) Lbs. Ft. (N.m) Lbs. In. (N.m) Lbs. Ft. (N.m) Lbs. In. (N.m) Diaphragm Screws 30 (3) Fuel Inlet Fitting* 95-130 (11-15) 10-18 (14-25) Fuel Line to Fuel Outlet Fitting Securely Securely Fuel Outlet Fitting (Note 1)* 95-130 (11-15) 10-18 (14-25) Fuel Pump to Block 20 (27) 20 (27) *NOTE 1: Coat fuel line inlet and outlet fitting threads with Loctite Pipe Sealant with Teflon, DO NOT use teflon tape. Torque to specifications. Fastene FasteneFastene r rr Locatio LocatioLocatio n nn AC Airtex Lbs. Ft. (N.m) Lbs. In. (N.m) Lbs. Ft. (N.m) Lbs. In. (N.m) Fuel Inlet Fitting* 10-18 (14-25) 10-18 (14-25) Fuel Line to Fuel Inlet Fitting Securely Securely Fuel Line to Fuel Outlet Fitting Securely Securely Fuel Outlet Fitting (Note 1) 10-18 (14-25) 10-18 (14-25) Fuel Pump to Block 20 (27) 20 (27) Sight Bulb to Fuel Pump Securely Securely *NOTE 1: Coat fuel line inlet and outlet fitting threads with Loctite Pipe Sealant with Teflon, DO NOT use teflon tape. Torque to specifications. 4A-2 -FUEL SYSTEM 90-95693 485 TOOLS/LUBRICANTS/SEALANTS TOOLS OBTAINED LOCALLY Fuel Pressure Gauge LUBRICANTS/SEALANTS 92-34227 Quicksilver Perfect Seal 92-42649 Quicksilver Needle Bearing Gasket SEALANTS OBTAINED LOCALLY Loctite Pipe Sealant with Teflon SPECIFICATIONS Type of Fuel Pump Carter (Low Volume) Carter (High Volume) AC Airtex Pump Pressure (1000 RPM) 5.0-6.5 PSI (35-44 kPa) Pump Pressure (1800 RPM) 5.25-6.5 PSI (36-44 kPa) 5.25-6.5 PSI (36-44 kPa) 5.5-7.0 PSI (38-48 kPa) Push Rod Length 5.76 in. (146.304mm) 5.76 in. (146.304mm) Push Rod Movement .344 in. (8.7376mm) .344 in. (8.7376mm) 90-95693 485 FUEL SYSTEM-4A-3 PRECAUTIONS ALWAYS disconnect battery cables from battery BEFORE working on fuel system to prevent fire or explosion. Be careful when changing fuel system components; gasoline is extremely flammable and highly explosive under certain conditions. Be sure that ignition key is "OFF". DO NOT smoke or allow sources of spark or flame in the area while working. Wipe up any spilled fuel immediately. DO NOT operate engine without cooling water being supplied to seawater pickup pump or pump impeller will be damaged, and subsequent overheating damage may result. Make sure that no fuel leaks exist, before closing engine hatch. FUEL DELIVERY SYSTEM RECOMMENDATIONS Boating industry standards (BIA, ABYC, etc.) federal standards and Coast Guard regulations MUST BE adhered to when installing fuel delivery system. When designing and installing fuel delivery svstem. the following information Ml ST BE observed: 1. Fuel tank should be mounted below carburetor level, if possible. If tank is mounted above carburetor level, gravitv feed may cause carburetor fuel inlet needle to unseat, and flooding may result. 2. Fuel pickup should be al least 1" (25mm) from the bottom of the fuel tank to prevent picking up water or other impurities. 3. Fuel lines used MUST BE Coast Guard approved (I'SCG type A) and MUST NOT BE SMALLER THAN 5/16" (8mm) ID. On installations where long lines or numerous fittings are required, larger size lines should be used. 4. Fuel line should be installed free of stress and firmly secured to prevent vibration and/or chafing. 5. Sharp bends in fuel line should be avoided. 6. A flexible fuel line must be used to connect fuel line to engine to absorb deflection when engine is running. DESCRIPTION The fuel system consists of a fuel tank(s). a water separating fuel filter (if so equipped), a fuel pump, and a carburetor. The fuel is stored in the fuel tank. When the engine is cranking or running, fuel is drawn from the fuel tank, through the water separating filter (if so equipped), by a mechanically operated fuel pump. The fuel pump is operated by the engine camshaft. The fuel is pushed through the fuel pump to the carburetor where it is metered and fed to the engine. 4B-4 - FUEL SYSTEM 90-95693 485 WATER SEPARATING FUEL FILTER NOTICE Refer to "Precautions", in this section, BEFORE proceeding. The water separating fuel filter is standard on some engines and can also be purchased as an option for engines not equipped with it. The fuel filter consists of the fuel filter base and filter element (Figure 1). IMPORTANT: If installing water separating fuel filter as an option, filter should be located between fuel tank and fuel pump. Also fuel inlet and outlet lines must be connected correctly for filter to work properly. (Figure 2) Follow instructions supplied with water separating fuel filter kit. Coat fuel line fitting threads with Loctite pipe sealant with teflon (do not use teflon tape). Torque to specifications. a - Filter Mounting Base b - Filter Element c - Sealing Rings d - Replacement Element Figure 1. a - Fuel Outlet if "C" is the Inlet c - Fuel Inlet if "A" is the Outlet b - Fuel Inlet if "D" is the Outlet d - Fuel Outlet if "B" is the Inlet Figure 2. 90-95693 485 FUEL SYSTEM - 4B-5 REPLACEMENT 1. Disconnect negative and positive battery leads from battery. 2. Remove filter element from mounting base by turning counterclockwise. You may need a filter wrench to break element loose. (Figure 3) IMPORTANT: Element cannot be cleaned and reused, it must be replaced. 3. Lubricate sealing rings with engine oil. (Figure 3) 4. Install new element. Tighten securely by hand. (F igure 3) 5. Start engine (making sure water is supplied to cooling system) and check for fuel leaks. a - Remove Old Filter b - Lubricate Sealing Rings with Engine Oil c - Install New Filter (Tighten Securely By Hand Only) Figure 3. Replacing Water Separating Fuel Filter 4A-6- FUEL SYSTEM 90-95693 485 FUEL PUMP FUEL FILTER REPLACEMENT NOTICE Refer to "Precautions", in this section, BEFORE proceeding. IMPORTANT: AC or Airtex pumps do not have a filter in the fuel pump. 1. Remove safely wire. 2. Loosen screw above filter bowl and release bail from fuel pump housing. 15998 a - Lockwire b - Retaining Screw c - Bail - Hook Ends in Slots d - Fitter Bowl e - Spring f - Fi ter Gasket - Open End at Filter TOWARD PUMP g - New Gasket Figure 2. Carter Pump (High Volume) 3. Remove bowl, filter element, spring, and gasket from fuel a - Retaining Screw (Lockwired) pump. b - Bail - Hook Ends in Slots 4. Install new filter as shown in Figure l or 2. c - Filter Bowl 5. Tighten retaining screw securely. d - Spring 6. Install safety wire and tighten securely. e - Filter Element - Open End of Filter TOWARD PUMP 7. Start and run engine. f - New Gasket 8. Check for gasoling leaks. Figure 1. Carter Pump (Low Volume) 9. If leaks exist. STOP ENGINE and recheck connections. 90-95693 485 FUEL SYSTEM - 4B-7 SIGHT TUBE or SIGHT GLASS INSPECTION Fuel pumps are equipped with a sight tube (Figures 1.2,3) or a sight glass. (Figure 4) Any evidence of fuel in the sight tube or sight glass indicates a ruptu~ed diaphragm and fuel pump must be replaced immediately. IMPORTANT: The low volume Carter Pump can be repaired with a diaphragm kit. All other fuel pumps must be replaced as an assembly. a - Sight Tube b - Fuel Pump Figure 3. Airtex Pump 15898 a - Sight Tube b - Fuel Pump Figure 1. Carter Pump (Low Volume) a - Sight Glass Figure 4. AC Pump (Dual Diaphragm) mmgmm 16788 a - Sight Tube b - Fuel Pump Figure 2. Carter Pump (High Volume) 4A-8 - FUEL SYSTEM 90-95693 485 SIGHT GLASS REPLACEMENT 1. Remove sigh! glass from fuel pump by turning fitting with a wrench. 2. Remove fitting by turning fitting out of sight glass. 3. Coat threads of fitting with sealer and install fitting into sight glass. Tighten securely. 4. Coat threads of fitting with sealer arid install fitting into fuel pump with a wrench. Tighten securely. TESTING NOTICE Refer to "Precautions", in this section, BEFORE proceeding. 1. Remove fuel line from outlet side of fuel pump. 2. Install fuel pressure test gauge to outlet side of fuel pump using T-fitting and appropriate adaptors. Coat fuel line inlet fitting threads Loctite pipe sealant with teflon (do not use teflon tape). Torque to specifications. FUEL PUMP 3. Connect fuel line (previously removed from pump) to other side of T-fitting on fuel pressure test gauge using appropriate adaptors. 4. Start engine and run at R.P.M. listed in specifications. 5. Fuel pressure should be within specifications. If not. repair or replace fuel pump. 6. Remove fuel pressure gauge and adaptors. Reconnect fuel line to fuel pump. Tighten to specifications. 90-95693 485 FUEL SYSTEM - 4B-9 CARTER PUMP (LOW VOLUME) NOTICE Refer to "Precautions", in this section, BE FORE proceeding. REMOVAL ACAUTION Plug fuel lines after disconnecting from fuel pump to eliminate any chance of fuel siphon 16 - Rocker Arm 17 - Rocker Arm Spring 18 - Screw 19 - Lockwasher ing into bilge. 1 - Filter Cover Retainer 2 - Filter Cover 3 - Filter Spring 4 - Filter 5 - Filter Gasket 6 - Pulsator Housing 7 - Pulsator 8 - Screw 9 - Lockwasher 10 - Valve Body 1. Disconnect fuel inlet and outlet lines at fuel pump. 2. Remove sight tube. 3. Remove 2 fuel pump mounting bolts and lockwashers. pump and gasket. DISASSEMBLY 1. Mark edges of fuel cover and bodv flange. Parts then may be reassembled in same relative position. 2. Loosen screw and remove filter holder, filter and gasket. 3. Remove screws, then pump body. 4. Remove screws and lockwasher and separate lower housing, pulsator. diaphragm and valve housing. 5. Remove spring, rocker arm shaft plug, safety pin. rorker arm shaft and rocker arm from main body. 6. Remove diaphragm seal assembly. 11 - Diaphragm 12 - Pump Body 13 - Rocker Arm Pin Plug 14 - Rocker Arm Pin 15 - Rocker Arm Retainer Figure 1. Low Volume Carter Fuel Pump 4A-10-FUEL SYSTEM 90-95693 485 CLEANING and INSPECTION 5. Assemble pump bodies with screws, making sure that 1. Clean and rinse all metal parts in solvent. Blow out all passages with compressed air. 2. Inspect pump body and fuel cover for cracks, breakage and distorted flanges. Examine all screw holes for stripped or crossed threads. Replace pump assembly if one of main castings is not serviceable. 3. Inspect rocker arm and link for excessive wear and for loose hinge pin. 4. Use proper diaphragm repair kit to replace diaphragm. 5. Replace rocker arm spring and diaphragm springs as removed. Old springs may be distorted, weak or corroded. 6. Check condition of valves by pushing each valve off its seat with a thin rod or pencil. Insert hooked wire thru inlet opening in fuel cover to move fuel inlet valve off its seat. If a valve sticks to its seat, if it moves off its seat and does not rebound or, if cage is damaged, complete valve must be replaced. To remove valves, clear staked metal (with a sharp chisel, file or suitable scraper) and pull valve out with a hook-shaped tool. REASSEMBLY 1. Replace diaphragm, pulsator, filter gasket and rocker arm shaft plug. 2. Push diaphragm into pump body and install rocker arm so that fork catches diaphragm. 3. Install rocker arm shaft, safety pin and rocker arm shaft plug. 4. Attach valve housing to lower housing with 2 screws. marks line up. Torque to specifications. IMPORTANT: Diaphragm must be flexed to its full stroke while tightening cover screws, or pump diaphragm protector will not be properly centered, thereby rubbing on the pump body casting and wearing diaphragm. 6. Reassemble filter to pump body, using new filter as previously outlined. INSTALLATION 1. Install new gasket (coat both sides with Perfect Seal) on fuel pump. Install pump and torque mounting bolts to specifications. 2. Install fuel line to fuel outlet fitting. Tighten securely. 3. Install fuel inlet fitting to fuel pump. Torque to specifications. Coat fuel line inlet fitting threads with Loctite pipe sealant with teflon (do not use teflon tape). Torque to specifications. 4. Install sight tube and fuel supply line. 5. Start engine and check for fuel leaks. CARTER PUMP (HIGH VOLUME) NOTICE 4. Install new gasket (coat both sides wich Perfect Seal) on Refer to "Precautions", in this section, BE-fuel pump. Install pump, arid torque mounting bolts to FORE PROCEEDING. specifications. 5. Install fuel line to fuel outlet fitting. Tighten securely. 6. Install fuel inlet fitting to fuel pump. Torque to specifica- IMPORTANT: The high volume Carter pump can tions. not be repaired. If fuel pump fails it must be replaced. REPLACEMENT Coat fuel line inlet fitting threads with Loctite pipe sealant with teflon (do not use teflon 1. Remove fuel inlet and outlet lines at fuel pump. tape). Torque to specifications. 2. Remove sight tube. 3. Remove 2 fuel pump mounting bolts and lockwashers. pump and gasket. 7. Install sight tube and fuel supplv line. 8. Start engine and check for fuel leaks. Plug fuel lines after disconnecting from fuel pump to eliminate any chance of fuel siphoning into bilge. 90-95693 485 EXHAUST SYSTEM- 5A-11 AC PUMP (DUAL DIAPHRAGM) NOTIC E 6. Check push rod movement bv installing push rod in engine, Refer to "Precautions", in this sections, BE-install a dial indicator against end of push rod. and turning FORE proceeding. engine over one complete revolution. Push rod should have total movement as shown in specifications. 7. Coat push red w ith Quicksilver Needle Bearing Grease and IMPORTANT: The AC fuel pump cannot be re-install in engine. paired. If the fuel pump fails it must be replaced. 8. Applv Perfect Seal to both sides of mounting plate gasket. Then, install gasket, plate, and mounting bolts. Tighten securely. 9. Applv Perfect Seal to both sides of fuel pump gasket. REPLACEMENT 10. Install gasket, fuel pump and mounting bolts. Torque bolts to specifications. 1. Remove fuel inlet and outlet lines at fuel pump. 1 1. Install fuel inlet and outlet fittings to fuel pump. Torque fittings to specifications. Tighten flare fittings securely. 12. Install sight glass (sight tube on later pumps). 13. Start engine and check for fuel leaks. Plug fuel lines after disconnecting from fuel pump to eliminate any chance of fuel siphoning into bilge. Coat fuel line inlet fitting threads with Loctite 2. Remove sight glass as outlined (sight tube on later pumps). pipe sealant with teflon (do not use teflon 3. Remove 2 fuel pump mounting screws, pump, and gasket. tape). Torque to specifications. 4. Remove mounting plate bolts, mounting plate, gasket, and push rod. 5. Check push rod length. See Specifications. AIRTEX PUMP 5. Check push rod length. See Specifications. NOTICE 6. Check push rod movement by installing push rod in engine, Refer to "Precautions", in this section, BE- install a dial indicator against end of push rod. and turning FORE proceeding. engine over one complete revolution. Push rod should have total movement as shown in specifications. 7. Coat push rod with Quicksilver Needle BearingGrease and IMPORTANT: The Airtex pump cannot be repaired. install in engine. If the fuel pump fails it must be replaced. 8. Apply Perfect Seal to both sides of mounting plate gasket ther install gasket, plate, and mounting bolts. Tighten securely. REPLACEMENT 9. Applv Perfect Seal to both sides of fuel pump gasket. 10. Install gaskel. fuel pump and mounting boll-. Torque to 1. Remove fuel inlel and outlet lines at fuel pump. specifications. 1 1. Install fuel inlel and outlet fittings to fuel pump. Torque fittings to specifications. Tighten flare fittings securelv. 12. Install sight tube. 13. Star! engine and check for fuel leaks. Plug fuel lines after disconnecting from fuel pump to eliminate any chance of fuel siphoning into bilge. Coat fuel line inlet fitting threads with Loctite 2. Remove sight tube. pipe sealant with teflon (do not use teflon 3. Remove 2 fuel pump mounting screws, pump, and gasket. tape). Torque to specifications. 4. Remove mounting plate bolls, mounting plate, gasket, and push rod. 4A-12 - FUEL SYSTEM 90-95693 485 HIGH FLOW FUEL PUMP KIT (42725A2) NOTICE Refer to "Precautions", in this section, BEFORE proceeding. NOTICE to INSTALLER MCM 485: If this fuel pump is used on an MCM 485, a new 90= fuel inlet fitting (22-68727) also is required. MCM 488R: If this fuel pump is used on an MCM 488R (serial 6671741 and below), a new fuel line (32-43275A1) also is required. High flow fuel pump is recommended as an improvement where vapor lock affects engine performance. This pump fits all MCM 470/470R/485/488R stern drive engines (serial 6671741 and below). REMOVAL OF EXISTING FUEL PUMP 1. Disconnect fuel inlet and outlet lines and sigh: tube from fuel pump. Remove and discard fuel outlet line. 2. Remove and discard 2 fuel pump mounting screws. 2 lock- washers, pump and gasket. Retain 2 flat washers. Clean gasket surface on cylinder block. Coat fuel line fitting threads with Loctite pipe sealant with teflon (do not use teflon tape). Torque to specifications. INSTALLATION OF KIT FUEL PUMP 1. Apply suitable fuel line thread sealant and install outlet fitting (from kit). Torque to specifications. 2. Lubricate rocker arm of kit pump with engine oil. Install pump using new, thick gasket. 2 lockwashers arid 2 screws (from kit) plus existing 2 flat washers. Pump filter bowl must be positioned down as shown. Torque screws to specifications. 3. Reconnect sight tube. 4. Install replacement fuel line (from kil on MCM 470.470R and 485. or obtained separately for MCM 488R). Loosen anti-vibration nut and grommet. Start both threaded ends at same time and check for cross threading. Then lighten securelv. Press grommet against fuel outlet nut and secure anti-vibration nut snugly. Do not overtighlen. 5. Apply suitable fuel line thread sealani and install fuel inlel fitting. Torque to specifications. 6. Reconnect batterv. Start and run engine. Check fuel line connections for gasoline leaks. a - Replacement Fuel Line b - Anti-Vibration Nut c - Fuel Outlet Nut d - Fuel Outlet Fitting e - Fuel Inlet Fitting t - Sight Tube g - Gasket Figure 1. Replacement Fuel Pump with Filter Bowl Inverted 90-95693 485 EXHAUST SYSTEM - 5A-13 SECTION 4 - FUEL SYSTEM PART B - ROCHESTER 2-BARREL INDEX Page Identification 4B-1 Replacement Parts Warning 4B-2 Torque Specifications 4B-2 Tools 4B-2 Specifications 4B-3 Adjustment Specifications 4B-4 Description 4B-5 Precautions 4B-5 Maintenance 4B-6 Flame Arrestor 4B-6 Flame Arrestor (with Carburetor Cover) 4B-6 Fuel Inlet Filter 4B-7 Choke Inspection 4B-7 Adjustments 4B-8 Float Level 4B-8 Float Drop 4B-8 Pump Rod 4B-9 Choke Setting 4B-10 Choke Unloader 4B-10 Preliminary Idle Speed and Mixture 4B-11 Final Idle Speed and Mixture 4B-11 Repair 4B-12 Removal 4B-12 Installation 4B-12 Disassembly 4B-12 Choke Housing Assembly 4B-14 Air Horn 4B-14 Float Bowl Assembly 4B-17 Throttle Body Assembly 4B-19 Cleaning and Inspection 4B-19 Reassembly 4B-20 Throttle Body Assembly 4B-20 Float Bowl Assembly 4B-21 Air Horn Assembly 4B-23 Choke Housing Assembly 4B-27 IDENTIFICATION 392 384-H a - Part Number a - Part Number (Embossed Tag) Carburetor Part Number Location Part Number Tag Location a - Two Idle Mixture Needles Rochester 2GC Carburetor 90-95693 485 FLEL SYSTEM-4B-4 REPLACEMENT PARTS WARNING Electrical, ignition and fuel system components on your MerCruiser are designed and manufactured to comply with U.S. Coast Guard Rulesand Regulationsto minimize risks of fire and explosion. Use of replacement electrical, ignition or fuel system components, which do not comply with these rules and regulations, could result in a fire or explosion hazard and should be avoided. Torque Specifications Fastener Location lb. ft. N m Banjo Fitting Bolt 30 41 Carburetor to Manifold 12 16 Fuel Line to Carburetor 18 24 Fuel Inlet Filter Nut 18 24 TOOLS MERCURY MARINE SPECIAL TOOLS 91-59339 Tachometer 91-36392 Universal Carburetor Gauge Borroughs Tool and Equipment 2429 N. Burdick St. Kalamazoo, Ml 49007 (616) 345-5163 BT8128B Float Gram Scale SPECIFICATIONS CARBURETOR MODEL SPECIFICATIONS Model (Serial No.) Type (Note 1) Manufacture Number Mercury Number Primary Jet Size Power Valve Size MCM 120 (5192047 and Below) Rochester 2GC 17044182 1351-6065 .062" .046" MCM 120 (5192048-6229717) Rochester 2GC 17059054 1351-7354 .062" .046" MCM 120R (6229718 and Above) Rochester 2GC 17081060 1351-8480 .062" .052" MCM 140 (5157668 and Below) Rochester 2GC 17043184 1351-5203 .062" .052" MCM 140 (5157669-6229717) Rochester 2GC 17059052 1351-7355 .062" .052" MCM 140R (6229718 and Above) Rochester 2GC 17081060 1351-8480 .062" .052" MCM 165 (5178958 and Below) Rochester 2GC 17043183 1351-5204 .061" .052" MCM 165 (5178959 and Up) Rochester 2GC 17059050 1351-7356 .067" .052" MCM/MIE 470 - MCM 470R (All) Rochester 2GC 17057132 1376-5990 .066" .052" MCM 485 (All) Rochester 2GC 17057132 1376-5990 .066" .052" MCM 898 (6021383 and Below) Rochester 2GC 17057139 1376-6491 .066" .055" MCM 898R (6021384 and Up) Rochester 2GC 17080350 1376-8295 .066" .055" NOTE 1. All Rochester carburetors are the 2GC type. The "C" designates the type of choke on the carburetor, NOT bore size. This information supercedes all previous Service Bulletins and service information. 90-95693 485 FUEL SYSTEM - 4B-4 UNIT OF MEASUREMENT in. (mm) CARBURETO R ADJUSTMEN T SPECIFICATION S (NOT E 1) Engine Model MCM 120 MCM 140 MCM 165 MIE/MCM 470 MCM 485 MCM 898 Carburetor Number 7044182 17059054 17081060 7043184 17059052 17081060 7043183 17059050 17057132 17057139 17080350 Float Level (Note 2) 5/8 (15.9) 5/8 (15.9) 5/8 (15.9) 11/16 (Note 3) (17.5) 5/8 (15.9) Float Drop (Note 2) 1-7/16 (36.5) 1-7/16 (36.5) 1-7/16 (36.5) 1-7/16 (36.5) 1-7/16 (36.5) Pump Rod 7/8 (22.2) 7/8 (22.2) 15/16 (23.8) 1-5/32 (29.4) 1-5/32 (29.4) Choke Setting Index Marks Aligned Index Marks Aligned Index Marks Aligned Index Marks Aligned Index Marks Aligned Choke Unloader .080 (2) .080 (2) .080 (2) .080 (2) .080 (2) Idle Mixture Screws Preliminary Setting 1-1/4 Turns 1-1/4 Turns 1-1/4 Turns 1-1/4 Turns 1-1/4 Turns Float Weight (grams) 10.81 g Max. 10.81 g Max. 10.81 g Max. 10.81 g Max. 10.81 g Max. NOTES 1. All measurements are ± 1/64" (,4mm). Information contained in this chart supercedes all Service Bulletins printed from 1978 thru 1984. 2. Measure from gasket to parting line on float. 3. Fuel inlet needle is spring loaded Before checking, raise flcat and allow to fall by itself. DO NOT FORCE downward by hand. 4B-4 - FUEL SYSTEM 90-95693 485 DESCRIPTION The 2GC is a 2-bore Rochester carburetor with an automatic choke. The last letter (in model type, "C" in this case), designats type of choke on carburetor, NO T bore size. Early model 2GC carburetors had a manifold heated choke element (via stove pipe), while ali later models use an electric heat choke element. The major portion of calibrated metering parts are contained in the venturi cluster (located in the float bowl) and may be serviced easily by removing the air horn assembly. Idle tubes and main discharge nozzles are pressed into venturi clusters and need not be serviced separately. Pump jets are part of venturi cluster also. Power restrictions are pressed into fuel bowl at factory, making replacement unnecessary. The primary jets and power valve assemblies are replaceable. PRECAUTIONS Always disconnect battery cables from battery BEFORE working on fuel system to preventfire or explosion. Make sure no fuel leaks exist, before closing engine hatch. DO NOT operate engine without cooling water being supplied to water pickup holes in gear housing, or water pump impeller will be damaged and subsequent overheating damage to engine may result. Be careful when cleaning flame arrestor and crankcase ventilation hose; gasoline is extremely flammable and highly explosive under certain conditions. Be sure that ignition key is "OFF". DO NOT smoke or allow sources of spark or open flame in area when cleaning flame arrestor and crankcase ventilation hose. Be careful when changing fuel system components; gasoline is extremely flammable and highly explosive under certain conditions. Be sure that ignition key is "OFF". DO NOT smoke or allow sources of spark or flame in the area while changing fuel filter. Wipe up any spilled fuel immediately. 90-95693 485 FUEL SYSTEM - 4B-5 MAINTENANCE FLAME ARRESTOR FLAME ARRESTOR with CARBURETOR COVER NOTICE Refer to "Precautions", in this section, BE FORE proceeding. 1. Remove in the following order: (Figure 1) a. Nut. b. Sealing washer. c. Hose clamp and crankcase ventilation hose - from flame arrestor and rocker arm cover. d. Flame arrestor - Lft from carburetor. 2. Clean and inspect: (Figure 1) a. Clean flame arres:or by blowing it out with compressed air. b. Clean crankcase ventilation hose. c. Inspect crankcase ventilation hose for cracks or deterioration, replace if necessary. 3. Install in the following order: (Figure 1) a. Flame arrestor - place on carburetor. b. Crankcase ventilation hose and clamp - to flame arrestor and rocker arm cover. c. Sealing washer. d. Nut - tighten securely. b - Sealing Washer d - Crankcase Ventilation Hose c- Hose Clamp . e - Flame Arrestor Figure 1. Cleaning Flame Arrestor and Crankcase Ventilation Hose 4B-6- FUEL SYSTEM NOTICE Refer to "Precautions", in this section, BE FORE proceeding. 1. Remove in the following order: (Figure 2) a. Nut. b. Sealing washer. c. Carburetor cover. d. Hose clamps and crankcase ventilation hoses - from flame arrestor and rocker arm covers. e. Flame arrestor - lift from carburetor. 2. Clean and inspect: (Figure 2) a. Clean flame arrestor in solvent and blow dry with compressed air. b. Clean crankcase ventilation hoses. c. Inspect crankcase ventilation hoses for cracks or deterioration, and replace if necessary. 3. Install in the following order: (Figure 2) a. Flame arrestor - place on carburetor. b. Crankcase ventilation hoses and hose clamps - to flame arrester and rocker arm covers. c. Carburetor cover. d. Sealing washer. e. Nut - tighten securely. b - Washer e - Crankcase Ventilation Hoses c - Carburetor Cover f - Flame Arrestor Figure 2. Flame Arrestor with Carburetor Cover 90-95693 485 FUEL INLET FILTER NOTICE Refer to "Precautions", in this section, BEFORE proceeding. Determine which type of fuel line to carburetor connector you are servicing (Figure 3 or 4). Follow proper sequence. a - Fuel Line b - Fuel Inlet Filter Nut c - Gasket d - Gasket e - Filter f - Spring Figure 4. Filter Nut Fuel Connector Remove in the following order: (Figure 4) a. Fuel line - from nut. b. Fuel inlet filter nut. c. Gaskets. 16000 d. Filter. e. Spring. a - "Banjo" Fitting Connecting Bolt d - Gasket b-Gaskets e - Spring Clean: c - Filter a. Filter nut and spring in solvent - dry with compressed air. Figure 3. "Banjo" Fitting Fuel Connector (470/485) 3. Install (in the following order): a. Spring. 1. Remove in the following order: (Figure 3) b. Filter - open end to filter nut. a. "Banjo" fitting connecting bolt. c. Gaskets - note sizes and location. b. Two large OD gaskets. d. Fuel inlet filter nut - Torque to specifications. c. Filter. e. Fuel line - Torque to specifications. d. Small gasket. 4. Inspect: e. Spring. a. Start and run engine. 2. Clean: b. Check fuel line connections for gasoline leaks. a. Connecting bolt and spring in solvent - dry with compressed air. 3. Install (in the following order): CHOKE INSPECTION a. New small gasket - place inside bolt. b. New filter - open end to bottom of bolt over gasket. The choke does not require any periodic maintenance; how- c. Spring - inside carburetor cavity. ever, if a choke malfunction is suspected, the following should d. Two new^ large OD gaskets - one on each side of bolt. be done: e. "Banjo" fitting connecting bolt - insert into carbure-1. With engine off. remove flame arrestor. tor, while holding components in position. Torque to 2. Open and close choke several times,and check for binding, specifications. Be careful not to pinch gasket. loose or disconnected linkages, or other signs of damage. 4. Inspect: 3. If choke or linkage binds, sticks, or works sluggishly, clean a. Start and run engine. with carburetor choke cleaner. Carefully follow directions b. Check fuel line connections for gasoline leaks. on car.. 90-95693 485 FUEL SYSTEM - 4B-7 ADJUSTMENTS 3. Bend float arm up or down at point shown in Figure 2, to NOTICE obtain specified dimension. Refer to "Precautions", in this section, BE 4. Visually check float alignment after adjustment. FORE proceeding. FLOAT LEVEL 1. Turn air horn upside down. Pivot float assembly up and down on hinge pin to ensure it moves freely. IMPORTANT: Before checking float level, raise float and allow it to fall; however, DO NOT FORCE DOWNWARD BY HAND. 2. Using Universal Carburetor Gauge, measure from gasket to toe of float. (Figure 1 and 1A) a - Bend Float Arm at This Point Figure 2. Adjusting Float Level FLOAT DROP 1. Hold air horn right-side-up to allow float to hang free. Air horn gasket MUST BE in place. 2. Using Universal Carburetor Gauge, measure from gasket to toe of float. (Figure 3) 332-HR a - See Specifications Figure 1. Measuring Float Level 18393 a - See Specifications Figure 3. Measuring Float Drop a - Measure From This Point to Gasket Figure 1A. Float Parting Line 4B-8 - FUEL SYSTEM 90-95693 485 3. Bend floal assembly tang, as shown in Figure 4, to obtain 2. With throttle valves COMPLETELY closed, measure from specified dimension. flame arrestor mounting surface to top of pump rod. (Fig4. Recheck BOTH float level and float drop. ure 6) 3. Carefully bend pump rod (where shown) to obtain specified dimension. (Figure 7) rV> a - See Specifications a - Float Assembly Tang Figure 6. Measuring Pump Rod Figure 4. Adjusting Float Drop PUMP ROD 1. Back out idle speed screw until it no longer contacts idle cam. (Figure 5) 392-H Figure 7. Adjusting Pump Rod a - Idle Speed Screw b - Idle Cam Figure 5. Backing Out Idle Speed Screw 17194 90-95693 485 FUEL SYSTEM - 4B-9 CHOKE SETTING Normal choke setting is such that scribed mark on cover is in line with long case mark on choke housing. (Figure 8) 392-H a - .080 In. (2.0mm) Drill Rod b - Choke Plate C - Air Horn Figure 9. Checking Choke Unloader 384-H a - Marks On Choke Cover and Choke Housing b- Leaner c - Richer Figure 8. Choke Setting If choke adjustment is necessary: 1. Loosen 3 choke cover retaining screws and adjust, as shown. 2. Tighten 3 choke cover retaining screws securely. CHOKE UNLOADER ADJUSTMENT 1. Hold throttle valves completely open. 2. Gently press down on choke plate. 3. Using an .080 in. (2.0mm) drill rod. or appropriate gauge, slide rod between upper edge of choke plate and air horn assembly. Rod should just slide through. (Figure 9) 4. Bend tang on throttle lever, if necessary, to obtain specified dimension. (Figure 10) 392-H a - Tang b - Throttle Lever Figure 10. Adjusting Choke Unloader 4B-10- FUEL SYSTEM 90-95693 485 PRELIMINARY IDLE SPEED and MIXTURE FINAL IDLE SPEED and MIXTURE IMPORTANT: The following adjustments will provide a sufficient idle speed and mixture for starting engine. Final adjustments MUST BE made with engine running. 1. Turn idle speed screw in until it just contacts idle cam; then, turn screw in an additional two turns. (Figure 11) 17194 a - Idle Speed Screw b - Idle Cam Figure 11. Idle Speed Screw IMPORTANT: DO NOT turn idle mixture needles tightly against seat (in the following step), as dam age to seat and/or needle may result. 2. Turn idle mixture needles in until they LIGHTLY SEAT; then, back needle out WA turns. (Figure 12) 16894 a - Two Idle Mixture Screws Figure 12. Idle Mixture Adjustment IMPORTANT: Boat MUST BE in the water and engine at normal operating temperature to accurately check and adjust idle speed and mixture. Carburetor should be set so that engine idles smoothly within range given under "Specifications", with boat in the water, engine at normal operating temperature and drive unit in forward gear. To adjust idle speed and mixture, proceed as follows: IMPORTANT: DO NOT attempt to compensate for other engine problems (incorrect ignition timing, faulty ignition components, low compression, vacuum leaks, etc.) with carburetor adjustments. This will only cover the problem, which must be corrected if engine is to achieve maximum fuel economy and performance. 1. Connect shop tachometer to engine. IMPORTANT: DO NOT turn idle mixture needles (Figure 1) tightly into seat, as damage to needle and/or seat may result. r- 16894 a - Two Idle Mixture Needles Figure 1. Idle Mixture Needle Location 2. If a new or rebuilt carburetor has been installed, turn each idle mixture needle (Figure 1) in (clockwise) until it LIGHTLY contacts seat: then, back ou: needle l'A turns. This will provide a sufficient setting to allow starting engine. 3. Start engine and run at 1500 RPM until engine reaches normal operating temperature. DO NOT leave the helm unoccupied while performing idle speed and mixture adjustments, following. BE CAREFUL NOT TO ACCIDENTALLY ACCELERATE ENGINE WHILE PERFORMING ADJUSTMENTS. 90-95693 485 EXHAUST SYSTEM - 5A-11 4. W ith boat in open water, place remote control in forward gear, idle position. 5. Disconnect throttle cable brass barrel from anchor stud. BE SURE NOT TO LOSE SPACER ON ANCHOR STUD. 6. Adjust idle speed adjustment screw (Figure 2) to obtain specified RPM. 7. With engine runningat specified RPM, adjust idle mixture needles (Figure 1), as follows: a. Turn idle mixture needle inward (clockwise) until the engine speed begins to drop due to lean mixture. b. Turn idle mixture screw outward (counterclockwise) until the speed begins to drop due to a rich mixture. c. Turn screw inward to a point between these two extremes to obtain maximum engine smoothness and RPM. d. Repeat procedure with other needle. e. Readjust idle speed adjusting screw, if necessary, to obtain specified RPM. IMPORTANT: Refer to "Section 2 (Removal, Instal- a - Idle Speed Adjustment Screw lation, and Alignment)" for throttle cable installation and adjustment. Figure 2. Idle Speed Adjusting Screw REPAIR NOTICE Refer to "Precautions", in this section, BEFORE proceeding. REMOVAL IMPORTANT: Carburetor malfunctions are, in many cases, caused by the presence of dirt, water or other foreign matter in carburetor. To aid in diagnosis, carefully remove carburetor from engine without draining fuel from bowl. Contents of fuel bowl may then be inspected for contamination as carburetor is disassembled. 1. Remove crankcase ventilation hose from flame arrestor: then, remove flame arrestor. IMPORTANT: Place a clean cloth in bores of carburetor to prevent dirt and foreign material from falling into bores. 2. Turn fuel supply off at fuel tank. 3. Disconnect throttle cable from carburetor. 4. Remove swivel link assembly from carburetor. 5. Remove fuel line. 6. Remove fuel pump sight tube from carburetor. 7. Disconnect choke. 8. Remove carburetor attaching nuts and washers and remove carburetor. 9. Remove and discard gaskets. IMPORTANT: Place a clean cloth over intake manifold opening to prevent dirt orforeign material from entering manifold. INSTALLATION 1. Thoroughly clean gasket surfaces. Use care to orevent 4B-12 - FUEL SYSTEM gasket material from entering intake manifold. 2. Place new carburetor base gasket on intake manifold. Install carburetor and secure with nuts and washers. Torque to specifications. Connect fuel line to fuel inlet nut and torque to specifications. Connect fuel pump sight tube to fitting on carburetor. Reconnect choke. Check to ensure that 8-12 threads of link rod are exposed from swivel: then, attach swivel link assembly lo throttle lever, using nut and washer. 7. Move intermediate throttle lever back-and-forth and check for binding in throttle linkage. If binding occurs, remove swivel link assembly from throttle lever and adjust link (by turning link rod), as required, to eliminate binding. 8. Install throttlecable.asexplained.in "Section2 (Removal, Installation, and Alignment)". 9. Install flame arrestor and crankcase ventilation hose. 10. Reconnect battery cables to battery. 11. Start engine and check for gasoline leaks. If leaks exist. STOP ENGINE IMMEDIATELY and recheckconnections. 12. Adjust idie speed and idle mixture, as outlined under Adjustments ', preceding. DISASSEMBLY The following is a step-by-step procedure for completely overhauling carburetor removed from engine. In many cases, however, complete overhaul is not necessary and, in these cases, onlv the steps required to repair the carburetor malfunction should be performed. Read the instructions carefully to prevent doing any unnecessary steps. IMPORTANT: Before performing any service on carburetor, it is essential that carburetor be placed in a holding fixture to prevent possible damage to throttle valves. 90-95693 485 1 - AIR HORN 2 - POWER PISTON ASSEMBLY 3-GASKET 4 - SCREW 5 - SCREW 6- LOCKWASHER 7 - NUT 8 - FILTER 9 - SPRING 10-GASKET 11 - GASKET 12-FLOAT ASSEMBLY 13 - PIN 14- CLIP 15 - INLET NEEDLE and SEAT ASSEMBLY 16 - GASKET 17 - FLOAT BOWL ASSEMBLY 18 - VENTURI CLUSTER ASSEMBLY 19-GASKET 20-SCREW 21 - GASKET 22-SCREW 23 - GUIDE 24 - SPRING 25 - BALL 26 - POWER VALVE ASSEMBLY 27 - GASKET 28-JET 29-LEVER 30-SCREW 31 - PUMP SHAFT and LEVER ASS'Y 32- ROD 33- CLIP 34- PUMP ASSEMBLY 35- CLIP 36 - SPRING 37 - GASKET 38 - THROTTLE BODY ASSEMBLY 39 - IDLE ADJUSTING NEEDLE 40-SPRING 41 - IDLE STOP SCREW 42- CLIP 43-GASKET 44 - SCREW 45 -LOCKWASHER 46 - CAM 47 - SCREW 48 - ROD 49 - CHOKE LEVER and COLLAR ASSEMBLY 50 - CHOKE SHAFT ASSEMBLY 51 - VALVE 52 - SCREW 53 - CHOKE HOUSING ASSEMBLY 54 - GASKET 55 - SCREW 56 - LEVER ASSEMBLY 57 - SCREW 58 - WELCH PLUG lEIectric Choke 59-PLUG ' Models Only 60 - COVER 61 - SCREW 62 - LOCKWASHER . Electric Choke 63- TERMINAL Models Only 64 - RETAINER Figure 1. Rochester Two-Barrel 90-95693 485 FUEL SYSTEM -4B-13 Choke Housing Assembly Air Horn 1. Remove choke cover. (Figure 2) 1. If not alreadv done, remove fuel inlet filter nut. washers, spring, and filter. 2. Remove accelerator pump rod retaining clip. (Figure 4) Pivot rod (as required) until retaining ear on rod and slot in pump shaft and lever assembly align, allowing rod to be pulled out. 384-H a - Screws b - Retainers c - Choke Cover Figure 2. Removing Choke Cover a - Accelerator Pump Rod b - Retainer Clip 2. Remove choke lever. (Figure 3) c - Pump Shaft and Lever Assembly 3. Remove choke housing assembly. (Figure 3) Figure 4. Removing Accelerator Pump Rod 3. Remove idle cam screw. (Figure 5) Also, remove choke rod bv pivoting rod (as required) until retaining ear on rod and slot in choke lever align, allowing rod to be pulled out. (Figure 6) 384-H a - Screw - Choke Lever b - Choke Lever c - Screws - Choke Housing Assembly d - Gasket e - Choke Housing Assembly Figure 3. Removing Choke Lever and Choke Housing Assembly a - Idle Cam Screw b-Idle Cam c - Choke Rod Figure 5. Removing Idle Cam 4A-14 - FUEL SYSTEM 90-95693 485 16941 a - Air Horn - Carefully Lift Off 4. Remove air horn as shown in Figures 7 and 8. b - Float Bowl Assembly Figure 8. Carefully Removing Air Horn 5. Invert air horn and carefullv lay on bench. 6. Remove float hinge pin and lift float assembly from air horn. (Figure 9) Check float weight as shown in Figure 9A. 7. Remove air horn gasket. (Figure 9) a - Choke Rod b - Choke Lever c- Slot Figure 6. Removing Choke Rod 17201 17200 a - Air Horn Attaching Screws (7 Short) b - Air Horn Attaching Screws (Long) Figure 7. Air Horn Attaching Screw Location a - Float Hinge Pin b - Float Assembly c - Air Horn Gasket Figure 9. Removing Float Assembly and Air Horn Gasket 90-95693 485 FUEL SYSTEM -4B-15 a - Needle Assembly b - Needle Seat c - Gasket Figure 11. Removing Needle Assembly. Needle Seat and Gasket a - Needle Assembly b - Needle Seat c - Gasket Figure 11. Removing Needle Assembly. Needle Seat and Gasket a - Grams Scale b - Float 11. Loosen accelerator pump screw. Slide pump shaft and lever Figure 9A. Checking Float Weight assembh (and washer) out ofair horn: then, remove accelerator pump assemblv and pump lever. (Figure 12) 12. To remove accelerator pump from pump lever, cut off swedged end of pump rod. (Figure 13) Replacement accelerator pump will have a groove and retainer clip for reinstallation. 17188 a - Baffle Figure 10. Removing Baffle 8. Remove baffle. (Figure 10) 9. Remove needle assembly. (Figure 11) 10. Remove needle seat and gasket. (Figure 11) a - Accelerator Pump Screw b - Pump Shaft and Lever Assembly c - Accelerator Pump Assembly d - Pump Lever Figure 12. Removing Pump Shaft and Lever Assembly and Accelerator Pump Assembly 4B-16- FUEL SYSTEM 90-95693 485 17183 a - Accelerator Pump Assembly b- Swedge - Cut Off c - Pump Shaft and Lever Assembly Figure 13. Removing Accelerator Pump Assembly IMPORTANT: Choke valve and shaft and lever assembly is not serviceable. If valve and/or shaft and lever assembly is worn or damaged, air horn assembly must be replaced. 13. To remove the power piston, push up and down against piston spring until piston comes loose from air horn. (Figure 13A) 17193 a - Power Piston b - Air Horn Figure 13A. Removing Power Piston Float Bowl Assembly 1. Remove accelerator pump return spring from pump well. (Figure 14) 2. Remove check ball (if equipped) from pump well. (Figure 14) 392-H a - Return Spring b - Refer to "IMPORTANT" following c - Pump Well Figure 14. Removing Accelerator Pump Return Spring and Check Ball IMPORTANT: Later model carburetors do not use a check ball. a - Power Valve Assembly b - Gasket Figure 15. Removing Power Valve Assembly 90-95693 485 FUEL SYSTEM - 4B-17 a - Spring Retainer Figure 18A. Removing Pump Discharge Ball a - Screws and Lockwashers Figure 17. Removing Venturi Cluster Attaching Screws 17185 a - Main Metering Jets Figure 16. Removing Main Metering Jets 3. Remove power valve assembly and gasket. (Figure 15) 4. Remove main metering jets and gaskets. (Figure 16) IMPORTANT: Use care when removing venturi cluster (in the following step) to prevent damaging brass tubes protruding from bottom of cluster. (Figure 18) DO NOTREMOVETUBES.These tubes are permanently pressed into the venturi cluster and are not replaceable. Place venturi cluster upside down on a clean work bench, after removal, to minimize the risk of damage to tubes. 5. Remove three venturi cluster screws (Figure 17), and carefully remove cluster and venturi gasket. (Figure 18) a - Venturi Cluster Brass Tubes b - Gasket Figure 18. Carefully Remove Venturi Clusters 6. Remove pump discharge, spring retainer, spring, and ball as shown in Figure 18A. 90-95693 485 4B-18- FUEL SYSTEM Throttle Body Assembly IMPORTANT: Use extreme care when handling throttle body, so as not to damage throttle valves. 1. Place float bowl assembly upside down. Remove three throttle body assembly attaching screws and lockwashers. and remove throttle body and gasket from float bowl. (Figure 19) 2. Remove idle mixture aa'justina needle and spring. (Figure 20) 3. Remove idle speed screw, if replacement is necessarv. (Figure 21) a - Screws b - Lockwashers c - Throttle Body - Gasket Not Seen In Photo Figure 19. Separating Throttle Body From Float Bowl Assembly a - Idle Mixture Adjusting Needles b- Springs Figure 20. Removing Idle Adjusting Needles and Springs a - Idle Speed Screw Figure 21. Removing Idle Speed Screw and Spring IMPORTANT: Throttle valves have been precisely fitted to throttle body, at the factory, and should not be removed under any circumstances. If any of the remaining throttle body parts are found to be worn or damaged, complete throttle body assembly MUST BE replaced. Throttle body assembly can be cleaned in carburetor cleaner. CLEANING and INSPECTION Carbon, varnish, gum, dirt, and water contaminants in the carburetor or on exterior moving parts of the carburetor often are responsible for carburetion malfunctions. Therefore, carefully observe the following cleaning and inspection procedure, to obtain effective carburetor repair. IMPORTANT: DO NOT use a wire or drill to clean jets, passages, or tubes in carburetor, as this may enlarge orifices and seriously affect carburetor calibration. IMPORTANT: DO NOT clean float bowl gasket surfaces with a gasket scraper or knife, as sealing bead will be damaged and float bowl replacement will be necessary. The float assembly, float needle, accelerator pump plunger, and fuel filter MUST NOT BE immersed in carburetor cleaner, as they will swell, harden, and/or distort. 90-95693 485 EXHAUST SYSTEM - 5A-19 i. Choke Valve and Shaft and Lever Assembly: Check shaft and lever assembly for excessive looseness in air horn assembly. Check choke valve and shaft and lever assembly for binding thru entire opera:ing range, making sure valve opens and closes completely. Air horn assembly MUST BE replaced if choke valve and shaft and lever assembly are worn or damaged, j. Inspect casting for visible damage. Inspect gasket surfaces. Inspect accelerator pump plunger well for scoring or deposits. REASSEMBLY Throttle Body Assembly a - Acce erator Pump b - Needle and Seat Assembly IMPORTANT: DO NOT force idle mixture needle c - Fuel Filter against seat as damage to needle and/or seat will d - Float Assembly result. Figure 22. Items Which MUST NOT BE Immersed In Carburetor Cleaner 1. Thoroughly clean all metal parts in a commercial carburetor cleaner, until all deposits have been removed. Follow manufacturer's instructions of cleaner being used for proper cleaning and rinsing procedure. Dry parts with compressed air. 2. Using compressed air, blow out all passages in carburetor to remove any foreign material. 3. Wipe-off all parts that cannot be cleaned in carburetor cleaner with a clean, dry cloth. 4. Carefully inspect all carburetor parts for wear and damage; pay particular attention to the following: a. Float Needle and Seat: If float needle or seat is worn or damaged, replace with a new needle and seat assembly. IMPORTANT: Float needle and seat are factory a - Idle Mixture Needles matched and tested and should be replaced as a b - Springs set only. Figure 1. Installing Idle Mixture Adjusting Needles and Springs b. Float Assembly and Hinge Pin: Inspect float pontoon for deterioration and porosity. Check pontoon density (to see if it is saturated with fuel), by comparing 1. Screw idle mixture needle (and spring) into throttle bodv weight of float with specifications. If pontoon weight until thev lightlv seat; then, back out needle 1 Vi turns as a is high, float assembly MUST BE replaced. Check hinge preliminary idle mixture setting. (Figure 1) Final adjust- pin and holes for wear. ment will be made with engine running. (Refer to c. Fuel and Air Passages: Passages MUST BE perfectly "Adj ustments".) clean for proper carburetor operation. 2. Thread idle speed screw and spring into throttle lever. d. Accelerator Pump Plunger and Return Spring: (Figure 2) Inspect pump plunger cup. pump plunger spring (on 3. Turn floal bowl assembly upside-down and place NEW pump assembly) and return spring. throttle bcdv gasket on bowl, making sure gasket is e. Power Piston Spring: Check power pislon spring for properly positioned on locating dowel. (Figure 3) weakness or distortion. f. Idle Mixture Needle: Inspect idle mixture needle. If damaged, needle MUST BE replaced. g. Levers and Linkages: Check levers, links and rods for wear. h. Throttle Valve and Shaft: Check throttle shaft for excessive looseness in throttle bodv. Check throttle valve and shaft for binding thru entire operating range, making sure valve opens and closes completely. Throttle bodv assembly MUST BE replaced if ihrottle valve and shaft are worn or damaged. 4B-20 - FUEL SYSTEM 90-95693 485 4. Install throttle body assembly on float bowl assembly, making sure that screw holes in gasket line up with screw holes in throttle bodv. (Figure 4) Tighten screws evenly and securely. a - Idle Speed Screw Figure 2. Installing Idle Speed Screw a - Screws b - Lockwashers c - Throttle Body Assembly Figure 4. Installing Throttle Body Assembly on Float Bowl Assembly Float Bowl Assembly IMPORTANT: Place float bowl and throttle assemblies in a holding fixture to prevent throttle valves from being damaged. a - Throttle Body Gasket b - Locating Dowel Figure 3. Throttle Body Gasket Properly Positioned on Float Bowl Assembly a - Spring Retainer Figure 4A. Installing Pump Discharge Ball 90-95693 485 FLEL SYSTEM-4B-21 1. Install pump discharge ball, spring, and spring retainer, as shown in Figure 4A. 2. Place new gasket over venturi cluster brass tubes. (Figure 5) Carefullv install venturi cluster in float bowl, using three screws, gaskets and lockwashers. as shown in Figure 6. Tighten screws evenly and securely. 16942 a - Venturi Cluster b - Gasket Figure 5. Placing Gasket on Venturi Cluster a - Venturi Cluster b - Center Screw (with smooth shank) c - Outer Screws d - Fiber Washer e - Lockwashers Figure 6. Installing Venturi Cluster a - Main Metering Jets Figure 7. Installing Main Metering Jets a - Power Valve Assembly b - Gasket Figure 8. Installing Power Valve Assembly 3. Install main metering jets and gaskets ir. bottom of float bowl assemblv: tighten jets securelv. (Figure 7) 4. Install power valve assemblv and gasket in bottom of float bowl assemblv and tighten securely. (Figure 8) 5. Place check ball (if so equipped) in pump well. (Figure 9) IMPORTANT: Later mode! carburetors do not have a check ball in accelerator pump well. Install a new check ball ONLY if carburetor had a ball in it when you took it apart. 4A-22 - FUEL SYSTEM 90-95693 485 Air Horn Assembly a - Refer to "IMPORTANT" Preceding Figure 9. Installing Check Ball, Strainer, and Retainer Clip 6. Place accelerator pump return spring in pump well. (Figure 10) IMPORTANT: Power piston must be fully seated in air horn casting. IMPORTANT: Accelerator pump assembly MUST BE installed correctly, as explained in the following step. If pump assembly is installed incorrectly, top of pump assembly will contact air horn casting. 2. If accelerator pump assemblv was removed from pump lever, secure new pump assemblv to pump lever with retainer c.ip. 3. Insert pump shaft and lever assemblv (and washer) into air horn: then.align indexed hole in pump lever with shaft and lever assembly and slide shaft all-the-way into lever so that shoulder on shaft is hitting lever. Tighten set screw- securely. (Figure 12) 392-H a - Accelerator Pump Return Spring b - Pump Well Figure 10. Installing Accelerator Pump a - Power Piston b - Screwdriver or Punch Figure 11. Installing Power Piston 1. Install power piston as shown in Figure 11. 90-95693 485 FUEL SYSTEM - 4B-23 4. Install needle seat and gasket, using appropriate width screwdriver. (Figure 13) 5. Place needle assemblv in needle seat. (Figure 14) 6. Install baff.e. (Figure 15) 7. Place new gasket on air horn. (Figure 16) 8. I nstall float assemblv and hinge pin. (Figure 17) Pivot float assemblv up-and-down on hinge pin to ensure it moves freelv. Set float level and drop to specifications. a - Pump Lever b - Set Screw c - Pump Shaft and Lever Assembly d - Washer e - Air Hern Figure 12. Installing Accelerator Pump Assembly and a - Needle Assembly Pump Shaft and Lever Assembly b - Needle Seat Figure 14. Installing Needle Assembly a - Needle Seat b - Gasket c - Screwdriver Figure 13. Installing Needle Seat and Gasket IMPORTANT: Float needle and needle seat are factory matched and tested and should be replaced as a set only. a - 3aff!e Figure 15. Installing Baffle 4A-24 - FUEL SYSTEM 90-95693 485 17170 17170 a - Gasket Figure 16. Installing Air Horn Gasket 17201 a - Air Horn b- Float Bowl Assembly Figure 18. Carefully Installing Air Horn a - Float Hinge Pin b - Float Assembly c - Gasket Figure 17. Installing Float Assembly and Hinge Pin 9. Place air horn on float bowl, making sure accelerator pump is correctlv positioned in fuel well. Lower air horn gentlv. straight down, to insure proper installation. (Figure 18) 10. Install seven shor; and one long air horn attaching screws. a - Seven Short Screws Tighten screws evenlv and securelv. (Figure 19) b - One Long Screw Figure 19. Installing Air Horn Attaching Screws 90-95693 485 FUEL SYSTEM - 4B-25 a - Choke Rod b - Choke Lever and Collar Assembly Figure 20. Installing Choke Rod 11. Place end of choke rod in chokc lever and collar assembly. (Figure 20) 12. Place idle cam on choke rod. (Figure 21) 13. Secure idle cam (with choke rod installed on cam) or. float bowl assembly, using screw. (Figure 22) Check that cam is free to move without binding. 17178 a - Idle Cam b - Choke Rod Figure 21. Installing Idle Cam 14. Place accelerator pump rod (end with ear) in hole in pump shaft and lever assemblv. (Figure 23) 15. Insert remaining end of accelerator pump rod into hole in throttle lever and secure with retainer clip. (Figure 23) a - Screw b - Idle Cam c - Choke Rod Figure 22. Securing Idle Cam to Float Bowl Assembly 17195 a - Accelerator Pump Rod b - Retainer Clip c - Pump Shaft and Lever Figure 23. Securing Accelerator Pump Rod to Throttle Lever 4B-26- FUEL SYSTEM 90-95693 485 Choke Housing Assembly 1695 6 a - Gasket b - Choke Housing Assembly Gasket Locating Pin Figure 24. Installing Choke Housing Assembly Gasket 1. Place new choke housing gasket in position on air horn making sure that, when installing choke housing assembly, locating pin on housing inserts into hole in gasket. (Figure 24) Secure choke housing assemblv to air horn with two attaching screws. (Figure 25) Tighten screws securely. Fasten choke lever to choke shaft assembly with screw, as shown in Figure 25. 4. Place choke cover on choke housing. Be sure hook on end of heating coil engages with choke lever. Rotate choke cover until alignment marks (made at disassembly) line up. 5. Secure choke cover with three screws and retainers (Figure 26), being sure ground terminal is fastened under bottom screw , if carburetor has an electric choke element. a - Choke Housing Assembly b - Choke Housing Assembly Attaching Screws c - Choke Lever d - Choke Lever Screw Figure 25. Installing Choke Housing Assembly and Choke Lever Assembly to Air Horn b - Retainer c - Choke Cover Figure 26. Installing Choke Cover 90-95693 485 EXHAUST SYSTEM - 5A-27 SECTION 4 - FUEL SYSTEM PART C - MERCARB® 2 BARREL INDEX Page Identification 4C-1 Replacement Parts Warning 4C-1 Torque Specifications 4C-2 Tools 4C-2 Specifications 4C-3 Description 4C-4 Precautions 4C-4 Maintenance 4C-5 Flame Arrestor 4C-5 Flame Arrestor with Carburetor Cover 4C-5 Fuel Inlet Filter 4C-6 Choke Inspection 4C-6 Adjustments 4C-7 Float Level 4C-7 Float Drop 4C-7 Pump Rod 4C-8 Choke Setting 4C-8 Choke Unloader 4C-9 Preliminary Idle Speed and Mixture 4C-9 Final Idle Speed and Mixture 4C-10 Repair 4C-11 Removal 4C-11 Installation 4C-11 Disassembly 4C-11 Choke Housing Assembly 4C-13 Air Horn 4C-13 Float Bowl Assembly 4C-16 Throttle Body Assembly 4C-17 Cleaning and Inspection 4C-18 Reassembly 4C-19 Throttle Body Assembly 4C-19 Float Bowl Assembly 4C-20 Air Horn Assembly 4C-22 Choke Housing Assembly 4C-25 IDENTIFICATION 384-H 392-H a - Part Number a - Part Number b - Date Code Figure 2. Part Number Tag Location Figure 1. Carburetor Part Number Location Date Code Explanation: Example 4501 First Figure is Year 4 = 1984 5 = 1985. etc. Second Figure is Month 5 = May 6 - June 7 = July etc. X = October Y = November Z = December Third and Fourth Figure is Day of Month 01 = First day 02 = Second day etc. a - Single Idle Mixture Needle Figure 3. MerCarb Carburetor REPLACEMENT PARTS WARNING 16923 Electrical, ignition and fuel system components on your MerCruiser are designed and manufactured to comply with U.S. Coast Guard Rules and Regulations to minimize risks of fire and explosion. Use of replacement electrical, ignition or fuel system components, which do not comply with these rules and regulations, could result in a fire or explosion hazard and should be avoided. 90-95693 485 FUEL SYSTEM - 4C-1 Torque Specifications Fastener Location lb. ft. N m Carburetor to Manifold 12 16 Fuel Line to Carburetor 18 24 Fuel Inlet Filter Nut 18 24 TOOLS MERCURY MARINE SPECIAL TOOLS 91-59339 Tachometer 91-36392 Universal Carburetor Gauge 90-95693 485 4C-2 - FUEL SYSTEM SPECIFICATIONS CARBURETOR MODEL SPECIFICATIONS Model Type Mercury Number Primary Jet Size Power Valve Size MCM 120R/140R MerCarb® 32mm 1389-8490 1.45mm ,84mm MCM 470R MerCarb® 35mm 1389-8489 1.65mm ,9mm MCM 898R MerCarb® 35mm 1389-8488 1,7mm 1 mm UNIT OF MEASUREMENT in. (mm) CARBURETOR ADJUSTMENT SPECIFICATIONS (Note 1) Engine Model MCM 120R/140R MCM 470R MCM 898R Carburetor Number 1389-8490 1389-8489 1389-8438 Float Level (Note 2) (Note 3) 5/8 (15.8) Float Drop (Note 2) 1-3/4 (44.5) Pump Rod 1-5/32 (29) Choke Setting Index Marks Aligned Choke Unloader .080 5/64 (2) !dle Mixture Screw Preliminary Setting 1-1/4 Turns Float Weight 9 Grams Max. NOTES: 1. All measurements are ± 1/64" (,4mm). Information contained in this chart supercedes all service bulletins and service information printed in 1984 and earlier. 2. Measurement is taken from gasket. Fuel inlet needle is spring loaded. Before checking raise float and allow to fall by itself. DO NOT FORCE downward by hand. 3. Spring loaded needle: 5/8" (15.8mm) Solid needle: 1/4" (6.3mm) 90-95693 485 FUEL SYSTEM - 4C-3 DESCRIPTION This MerCarb carburetor is a two bore carburetor and has a pump jets built into it. The venturi cluster is serviced as a unit. separate fuel feed for each venturi. This model also is equipped The serviceable main metering jets are a fixed orifice type that with an electric choke. A removable venturi cluster (secured to work together with fixed air bleeds to properly meter the float bowl assembly) has the calibrated main well tubes and correct fuel/air mixture to the engine. PRECAUTIONS 4C-4 - FUEL SYSTEM 90-95693 485 MAINTENANCE FLAME ARRESTOR FLAME ARRESTOR WITH CARBURETOR COVER NOTICE Refer to "Precautions", in this section, BE NOTICE FORE proceeding. Refer to "Precautions", in this section, BEFORE proceeding. 1. Remove in the following order: (Figure 1) a. Nut. 1. Remove in the following order: (Figure 2) b. Sealing washer. a. Nut. c. Hose clamp and crankcase ventilation hose - From b. Sealing washer. flame arrestor and rocker arm cover. c. Carburetor cover. d. Flame arrestor - Lift from carburetor. d. Hose clamps and crankcase ventilation hoses - From 2. Clean and inspect: (Figure 1) flame arrestor and rocker arm covers. a. Clean flame arrestor bv blowing it out w ith compressed e. Flame arrestor - Lift from carburetor. air. 2. Clean and inspect: (Figure 2) b. Clean crankcase ventilation hose. a. Clean flame arrestor in solvent and blow drv with c. Inspect crankcase ventilation hose for cracks or detericompressed air. oration, and replace if necessary. b. Clean crankcase ventilation hoses. 3. Install in the following order: (Figure 1) c. Inspect crankcase ventilation hoses for cracks or detea. Flame Arrestor - Place on carburetor. rioration. and replace if necessary. b. Crankcase ventilation hose and hose clamp - To flame 3. Install in the following order: (Figure 2) arrestor and rocker arm cover. a. Flame arrestor - Place on carburetor. c. Sealing washer. b. Crankcase ventilation hoses and hose clamps - To flame d. Nut - Tighten securelv. but do not overtighten. arrestor and rocker arm covers. c. Carburetor cover. b - Sealing Washer d - Crankcase Vent lation Hose a - Nut d - Clamps c - Hose Clamp e - Flame Arrestor b - Washer e - Crankcase Ventilation Hoses c - Carburetor Cover f - Flame Arrestor Figure 1. Flame Arrestor Figure 2. Flame Arrestor with Carburetor Cover 90-95693 485 FUEL SYSTEM - 4C-5 FUEL INLET FILTER 2. Clean filter nut and spring in solvent and dry with com pressed air. 3. Install in the following order: (Figure 3) NOTIC E a. Spring - Place in carburetor body. Refer to "Precautions", in this section, BE-b. Filter - Open end to inlet filter nut. FORE proceeding. c. Small gasket - Place inside filter nut. d. Large gasket - Place over filter nut. e. Fuel inlet filter nut - Torque to specifications. 1. Remove in the following order: (Figure 3) f. Fuel line - Torque to specifications. a. Fuel line from fue: inlet filter nut. b. Fuel inlet filter nut. c. Large gasket. CHOKE INSPECTION d. Filter. e. Spring. The choke does not require anv periodic maintenance: how- f. Small gasket • From inside filter nut. ever. if a choke malfunction is suspected, the following should be done: 1. With engine off, remove flame arrestor. 2. Open and close choke several times, and check for binding, loose or disconnected linkages, or other signs of damage. 3. If choke or linkage binds, sticks, or works sluggishly, clean with carburetor choke cleaner. Follow directions on can. a - Fuel Line b - Fuel Inlet Filter Nut c - Gasket (Large) d - Gasket (Small) e - Filter f - Spring Figure 3. Carburetor Fuel Inlet Filter 15903 4C-6 - FUEL SYSTEM 90-95693 485 ADJUSTMENTS NOTICE Refer to "Precautions", in this section, BEFORE proceeding. FLOAT LEVEL 1. Turn air horn upside down. Pivot float assembly up-anddown on hinge pin to ensure it moves freely. IMPORTANT: Before checking float level, raise float and allow it to fall; however, DO NOT force downward by hand. 2. Using Universal Carburetor Gauge, measure from gasket to toe of float. (Figure 1 and 1A) a - Bend Float Arm at this Point Figure 2. Adjusting Float Level FLOAT DROP 1. Hold air horn right-side-up to allow float to hang free. 2. Using Universal Carburetor Gauge, measure from gasket to toe of float. (Figure 3) a - See Specifications Figure 1. Measuring Float Level 392-H a - Measure from This Point to Gasket Figure 1A. Toe of Float 18081 a - See Specifications Figure 3. Measuring Float Drop 3.4. Bend float arm up or down at point shown in Figure 2. to obtain specified dimension. Visually check float alignment after adjustment. 3.4. Bend float assemblv lang. as shown in Figure 4. to obtain specified dimension. Recheck BOTH float level and float drop. FUEL SYSTEM - 4C-7 90-95693 485 392-H a - Float Assembly Tang Figure 4. Adjusting Float Drop PUMP ROD 1. Back out idle speed screw until it no longer con:acts idle cam. (Figure 5) 16930 a - Idle Speed Screw b - Idle Cam Figure 5. Backing Out Idle Speed Screw 2. With throttle valves completely closed, measure from flame arrestor mounting surface to top of pump rod. (Figure 6) 3. Carefullv bend pump rod (where shown) to obtain specified dimension. (Figure 7) a - Marks on Choke Cover and Choke Housing b - Leaner c - Richer Figure 8. Choke Setting 392-H a - See Specifications Figure 6. Measuring Pump Rod 392-H Figure 7. Adjusting Pump Rod CHOKE SETTING Normal choke setting is such that scribed mark on cover line with long case mark on choke housing. (Figure 8) 384-H 90-95693 485 :-8 - FUEL SYSTEM If choke adjustment is necessary: 1. Loosen 3 choke cover retaining screws and adjust as shown. 2. Tighten 3 choke cover retaining screws securelv. CHOKE UNLOADER 1. Hold throttle valves completely open. 2. Gently press down on choke plate. 3. Using an .080 in. (2.0mm) drill rod. or appropriate gauge, slide rod between upper edge of choke plate ar.d air horn assembly. Hod should just slide through. (Figure 9) If adjustment is required, proceed to Step 4. 4. Bend tang on throttle lever, if necessarv. to obtain specified dimension. (Figure 10) a - idle Speed Screw b - Idle Cam Figure 11. Preliminary Adjustment of Idle Speed Screw PRELIMINARY IDLE SPEED and MIXTURE IMPORTANT: The following adjustments will provide a sufficient idle speed and mixture for starting engine. Final adjustments must be made with engine running. 1. Turn idle speed screw in until il jusl contacts idle cam: then, turn screw in an additional two turns. (Figure 11) IMPORTANT: DO NOT turn idle mixture needle tightly against seat (in the following step), as damage to seat and/or needle may result. 2. Turn idle mixture needle in until they lightlv seat; then, back needle out IVi turns. (Figure 12) 392-H a - .080 In. (2.0mm) Drill Rod b - Choke Plate c - Air Horn Figure 9. Checking Choke Unloader a - Tang b - Throttle Lever Figure 10. Adjusting Choke Unloader a - Idle Mixture Needle Figure 12. Preliminary Idle Mixture Adjustment 90-95693 485 FUEL SYSTEM-4C-9 FINAL IDLE SPEED and MIXTURE IMPORTANT: Boat must be in the water and engine at normal operating temperature to accurately check and adjust idle speed and mixture. Carburetor should be set so that engine idles smoothly within range given under "Specifications", with boat in the water, engine at normal operating temperature and drive unit in forward gear. To adjust idle speed and mixture, proceed as follows: IMPORTANT: DO NOT attempt to compensate for other engine problems (incorrect ignition timing, faulty ignition components, low compression, vacuum leaks, etc.) with carburetor adjustments. This will only cover the problem, which must be corrected if engine is to achieve maximum fuel economy and performance. 1. Connect an accurate shop tachometer to engine. IMPORTANT: DO NOT turn idle mixture needle (Figure 1) tightly into seat, as damage to needle and/or seat may result. 16923 a - Idle Mixture Needle Figure 2. Carburetor Idle Mixture Needle 2. If a new or rebuilt carburetor has been installed, turn idle mixture needle (Figure 1) in (clockwise) until it lightly contacts seat; then, back out needle l'A turns. This will provide a sufficient setting to allow starting engine. 3. Start engine and run at 1500 RPM until engine reaches normal operating temperature. 4. ith boat in open water, place remote control in forward gear, idle position. 5. Disconnect throttlecable brass barrel from anchor stud. Be sure not to lose spacer on anchor stud. 6. Adjust idle speed adjustment screw (Figure 2) to obtain specified RPM. 7. With engine runningat specified RPM. adjust idle mixture needle (Figure 1), as follows: a. Turn idle mixture needle inward (clockwise) until the engine speed begins to drop due to lean mixture. b. Turn idle mixture screw outward (counterclockwise) until the speed begins to drop due to rich mixture. c. Turn screw inward to a point between these two extremes to obtain maximum engine smoothness and RPM. d. Readjust idle speed adjusting screw, if necessary, to obtain specified RPM. IMPORTANT: Refer to "Section 2 (Removal, Instal lation and Alignment)" for throttle cable installation and adjustment. a - Idle Speed Adjustment Screw Figure 2. Idle Speeed Adjusting Screw 4C-10- FUEL SYSTEM 90-95693 485 REPAIR NOTICE Refer to "Precautions", in this section, BEFORE proceeding. REMOVAL IMPORTANT: Carburetor malfunctions are, in many cases, caused by the presence of dirt, water or other foreign matter in carburetor. To aid in diagnosis, carefully remove carburetor from engine without draining fuel from bowl. Contents of fuel bowl may, then, be inspected for contamination as carburetor is disassembled. 1. Remove ventilation hose from flame arrestor: then, remove flame arrestor. IMPORTANT: Place a clean cloth in bores of carburetor to prevent dirt and foreign material from falling into bores. 2. Turn fuel supplv off at fuel tank. 3. Disconnect throttle cable from carburetor. 4. Remove swivel link assembly from carburetor. 5. Remove fuel line from fuel inlet nut. 6. Remove fuel pump sight tube from carburetor. 7. Disconnect electric choke. 8. Remove carburetor attaching nuts and washers and remove carburetor. 9. Remove and discard gaskets. IMPORTANT: Place a clean cloth over intake mani fold opening to prevent dirt or foreign material from entering manifold. INSTALLATION 1. Thoroughly clean gasket surfaces. 2. Place new carburetor base gasket on intake manifold. Install carburetor and secure with nuts and washers. Torque to specifications. 3. Connect fuel line to fuel inlet nut and torque to specifications. 4. Conncet fuel pump sight tube to fitting on carburetor. 5. Connect electric choke wires to choke cover. 6. Check to ensure that 8-12 threads of link rod are exposed from swivel; then, attach swivel link assembly to throttle lever, using nut and washer. 7. Move intermediate throttle lever back-and-forth and check for binding in throttle linkage. If binding occurs, remove swivel link assembly from throttle lever and adjust link (by turning link rod), as required, to eliminate binding. 8. Install throttle cable, as explained, in "Section 2". 9. Install f.ame arrestor and crankcase ventilation hose. 10. Reconnect battery cables to battery. 11. Start engine and check for gasoline leaks. If leaks exist. STOP ENGINE IMMEDI ATELY and recheck connections. 12. Adjust idle speed and idle mixture, as outlined under "Adjustments" preceding. DISASSEMBLY The following is a step-bv-step procedure for completely overhauling carburetor removed from engine. In many cases, however. complete overhaul is not necessarv and, in these cases, only the steps required to repair the carburetor malfunction should be performed. Read the instructions carefully to prevent doing any unnecessary steps. IMPORTANT: Before performing any service on carburetor, it is essential that carburetor be placed in a holding fixture to prevent possible damage to throttle valves. 90-95693 485 FUEL SYSTEM - 4C-11 1 - Air Horn 20 -Lockwasher 2 - Gasket 21 - Gasket 3 - Screw 22 - Gasket 4 - Screw 23 Power Valve Assembly 5 - Lockwasher 24 - Gasket 6-Nu t - Fuel Inlet 25 -Jet 7 - Gasket 26 Gasket 8 - Gasket 27 - Pump Shaft and Lever Assembly 9 - Spring 28 - Screw 10 - Filter 29 - Washer 11 - Inlet Needle and Seat 30 - Clip - Retainer 12 - Baffle Plate 31 - Accelerator Pump Assembly 13 - Pin 32 - Spring 14 - Float 33 - Clip - Retainer 15 - Float Bowl 34 - Strainer 16 - Venturi Cluster 35 - Check Ball 17 - Gasket 36 - Cam - Idle 18 - Screw 37 - Screw 19 - Screw 38 - Throttle Body 4C-12 - FUEL SYSTEM 39 - Gasket 40 - Idle Mixture Adjusting Needle 41 - Spring 42 - Screw - Idle Speed Adjusting 43 - Spring 44 - Screw 45 - Lockwasher 46 - Choke/Housing 47 - Gasket (Some Models) 48 - Screw 49 - Lever Assembly 50 - Screw 51 - Rod - Choke 52 - Rod - Accelerator Pump 53 - Accelerator Pump Shaft and Lever Assembly 54 - Washer - (Outer) 55 - Washer - (Inner) 90-95693 485 Choke Housing Assembly Air Horn 1. Remove choke cover as shown in Figure 2. 1. Remove fuel inlet filler nut. washers, spring, and filter, as outlined. 2. Remove accelerator pump rod retaining clip. (Figure 4) Pivot rod (as required) until retaining ear on rod and slot in pump shaft and lever assembly align, allowing rod to be pulled out. 384-H a - Accelerator Pump Rod b - Retainer Clip c - Pump Shaft and Lever Assembly Figure 4. Removing Accelerator Pump Rod Figure 2. Removing Choke Cover 2. Remove choke lever as shown in Figure 3. 3. Remove choke housing assembly as shown in Figure 3. 384-H Figure 3. Removing Choke Lever and Choke Housing Assembly 90-95693 485 FUEL SYSTEM - 4C-13 Remove idle cam screw. (Figure 5) Also, remove choke rod bv pivoting rod (as required) until retaining ear on rod and slot in choke lever align, allowing rod to be pulled out. (Figure 6) a - Idle Cam Screw b - Idle Cam c - Choke Rod Figure 5. Removing Idle Cam 16926 16941 c - Slot a - Choke Rod b - Choke Lever Figure 6. Removing Choke Rod 4. Remove air horn as shown in Figures 7 and 8. a - Air Horn Attaching Screws Figure 7. Air Horn Attaching Screw Location a - Air Horn - Carefully Lift Off b - Float Bowl Assembly Figure 8. Carefully Removing Air Horn 90-95693 485 4C-14 - FUEL SYSTEM 5. Invert air horn and carefully lay on bench. 6. Remove float hinge pin and lift float assembly from air horn. (Figure 9). Check float weight as shown in (Figure 9A). 7. Remove air horn gasket. (Figure 9) a - Baffle Figure 10. Removing Baffle 8. Remove baffle. (Figure 10) 9. Remove needle assembly. (Figure 11) 10. Remove needle seat and gasket. (Figure 11) 18150 a - Float Hinge Pin b - Float Assembly c - Air Horn Gasket Figure 9. Removing Float Assembly and Air Horn Gasket a - Needle Assembly b - Needle Seat c - Gasket Figure 11. Removing Needle Assembly, Needle Seat and Gasket IMPORTANT: MCM 120R/140R Only: Carburetors with a dale code of 4801 and above use a "solid type" needle and seat in production. Carburetors before that date code may have solid needle installed as service kit. a - Grams Scale b - Float Figure 9A. Checking Float Weight 90-95693 485 EXHAUST SYSTEM - 5A-15 IMPORTANT: Choke valve and shaft and lever assembly is not serviceable. If valve and/or shaft and lever assembly is worn or damaged, air horn assembly must be replaced. Float Bowl Assembly 1. Remove accelerator pump return spring from pump well. (Figure 14) 2. Carefullv remove retainer clip, strainer, and check ball from pump well. (Figure 14) 18082 a - "Spring Loaded Type" Needle-MCM 120R/140R (Early Models) and MCM 470R/898R b - "Solid Type" Needle - MCM 120R/140R (Later Models) Only Figure 11 A. Types of Needle and Seat Assemblies 11. Loosen accelerator pump screw. Slide pump shaft and lever assembly (and washer) out of air horn: then, remove accelerator pump assembly and pump lever. (Figure 12) 12. Remove retainer clip and washer from pump shaft and lever assembly: then, remove accelerator pump assembly. (Figure 13) 392-H a - Accelerator Pump Return Spring d - Check Ball b - Retainer Clip e - Pump Well c - Strainer Figure 14. Removing Accelerator Pump Return Spring, Retainer Clip, Strainer, and Check Ball a - Accelerator Pump Screw c - Accelerator Pump b - Pump Shaft and Lever Assembly d - Pump Lever Figure 12. Removing Pump Shaft and Lever Assembly and Accelerator Pump Assembly o 18154 a - Power Valve Assembly b - Gasket Figure 15. Removing Power Valve Assembly a - Accelerator Pump Assembly o - Retainer Clip c - Pump Shaft and Lever Assembly Figure 13. Removing Accelerator Pump Assembly 4C-16- FUEL SYSTEM 90-95693 485 3. Remove power \alve assembly and gaskel. (Figure 15) 4. Remove main metering jets and gaskets. (Figure 16) 16937 16935 a - Venturi Cluster Brass Tubes b - Gasket Figure 18. Carefully Remove Venturi Clusters a - Main Metering Jets - Gaskets Not Seen In Photo Figure 16. Removing Main Metering Jets Throttle Body Assembly IMPORTANT: Use extreme care when handling throttle body, so as not to damage throttle valves. 1. Place float bowl assembly upside down. Remove ihree throttle body assembly attaching screws and lockwashers. and remove throttle bod\ and ga.-kel from floal bowl. (Figure 19) a - Screws/Lockwashers Figure 17. Removing Venturi Cluster Attaching Screws IMPORTANT: Use care when removing venturi cluster to prevent damaging brass tubes protruding from bottom of cluster. DO NOT REMOVE TUBES. These tubes are permanently pressed into the 16953 venturi cluster and are not replaceable. 5. Remove three venturi cluster screws (Figure IT), and care- fulls remove cluster and venturi gasket. (Figure 18) a - Screws b - Lockwashers c - Throttle Body - Gasket Not Seen in Photo Figure 19. Separating Throttle Body From Float Bowl Assembly 90-95693 485 FUEL SYSTEM - 4C-17 2. Remove idle mixture adjusting needle and spring. (Figure 20) 3. Remove idle speed screw and spring, if replacement is necessary. (Figure 21) a - Idle Mixture Adjusting Needle b - Spring Figure 20. Removing Idle Adjusting Needle and Spring IMPORTANT: DO NOT remove throttle valves. If any of the throttle body parts are found to be worn or damaged, complete throttle body assembly MUST BE replaced. Throttle body assembly can be cleaned in carburetor cleaner. CLEANING and INSPECTION IMPORTANT: DO NOT use a wire or drill to clean jets, passages, or tubes in carburetor, as this may enlarge orifices and seriously affect carburetor calibration. IMPORTANT: DO NOT clean float bowl gasket surfaces with a gasket scraper or knife, as sealing bead will be damaged and float bowl replacement will be necessary. 16950 a - Idle Speed Screw b - Spring Figure 21. Removing Idle Speed Screw and Spring a - Accelerator Pump Plunger b - Float Needle c - Fuel Filter d - Float Assembly Figure 22. Items Which MUST NOT BE Immersed in Carburetor Cleaner 4B-18 - FUEL SYSTEM 90-95693 485 1. Thoroughly clean all metal parts in a commercial carburetor cleaner, until all deposits have been removed. Follow manufacturer's instructions of cleaner being used for proper cleaning and rinsing procedure. Dry parts with compressed air. 2. Using compressed air. blow out all passages in carburetor to remove any foreign material. 3. Wipe-off all parts that cannot be cleaned in carburetor cleaner with a clean, dry cloth. 4. Carefullv inspect all carburetor parts for wearanc damage: pay particular attention to the following: a. Float Needle and Seat: If float needle or seat is worn or damaged, replace with a new needle and seat assembly. IMPORTANT: Float needle and seat are factory matched and tested and should be replaced as a set only. b. Float Assembly and Hinge Pin: Check pontoon density (tosee if it issaturated with fuel), by comparing weight of float with specifications. If pontoon weight is high, float assemblv must be replaced. Check hinge pin and holes for wear. c. Fuel and Air Passages: Passages must be perfectly clean for proper carburetor operation. d. Accelerator Pump Plunger and Return Spring: Inspect pump plunger cup. pump plunger spring (on pump assembly) and return spring. e. Power Piston Spring: Check power piston spring for weakness or distortion. f. Idle Mixture Needle: Inspect idle mixture needle. If damaged, needle must be replaced. g. Levers and Linkages: Check levers, links and rods for wear. h. Throttle Valve and Shaft: Check throttle shaft for excessive looseness in throttle body. Check throttle valve and shaft for binding thru entire operating range, making sure valve opens and closes completely. Throttle bodv assemblv must be replaced if throttle valve and shaft are worn or damaged. i. Choke \ alve and Shaft and Lever Assembly: Check shall and lever assemblv for excessive looseness in air horn assembh . Check choke valve and shaft and lever assemblv for binding ihru entire operating range, making sure valve opens and closes completely. Air horn assembly must be replaced if choke valve and shafl and lever assemblv are worn or damaged. Inspect Casting; for visible damage. Inspect gasket surfaces. Inspect accelerator pump plunger well for scoring or deposits. REASSEMBLY Throttle Body Assembly IMPORTANT: DO NOT force idle mixture needle against seat as damage to needle and/or seat will result. a - Idle Mixture Needle b - Spring Figure 1. Installing Idle Mixture Adjusting Needle and Spring 1. Screw idle mixture needle (and springl into throttle bodv until they lightly seat: then, back out needle 1 Vi turns as a preliminary idle mixture setting. (Figure 1) Final adjustment will be made w ith engine running. Refer to \djustments". 2. Thread idle speed screw and spring into throttle lever. (Figure 2) 3. Turn float bow] assembly upside-down and place new- throttle bodv gasket on bowl, making sure gasket is properly positioned on locating dowel. (Figure 3) a - Idle Speed Screw b - Spring Figure 2. Installing Idle Speed Screw 90-95693 485 FUEL SYSTEM-4C-19 IMPORTANT: Place float bowl and throttle assemblies in a holding fixture to prevent throttle valves from being damaged. Figure 3. Throttle Body Gasket Properly Positioned on Float Bowl Assembly :6942 IMPORTANT: Place float bowl and throttle assemblies in a holding fixture to prevent throttle valves from being damaged. Figure 3. Throttle Body Gasket Properly Positioned on Float Bowl Assembly :6942 a - Throttle Body Gasket b - Locating Dowel a - Venturi Cluster d - Fiber Washer b - Center Screw (With Smooth Shank) e - Lockwashers c - Outer Screws f - Metal Gaskets Figure 6. Installing Venturi Cluster Float Bowl Assembly a - Venturi Cluster b - Gasket Figure 5. Placing Gasket on Venturi Cluster I. Place new gasket over venturi cluster brass lubes. (Figure 3) Carefully, install venturi cluster in floal bowl, using three screws, gaskets and lockwashers as shown in F igure 6. Tighten screws evenly and securely. a - Screws b - Lockwashers c - Throttle Body Assembly Figure 4. Installing Throttle Body Assembly on Float Bowl Assembly 4. Install throttle bodv assemblv on float bowl assemblv. making sure that screw holes in gasket line up with screw holes in throttle bodv. (Figure 4) l ighten screws evenlv and securelv. 4C-20 - FUEL SYSTEM 90-95693 485 16937 a -Main Metering Jets Figure 7. Installing Main Metering Jets 16925 a - Power Valve Assembly b - Gasket Figure 8. Installing Power Valve Assembly 2. It Install main metering jets and gaskets in bottom of float bowl assemblv: ighlen jets securely. (Figure 7) 3. Install power valve assemblv and gasket in bottom of float bowl assembly and lighten securely. (Figure 8) 4. Place check ball in pump well: then, install strainer and retainer clip. (Figure 9) DO NOT use pliers to install clip. 5. Place accelerator pump return spring in pump well. (Figure 10) a - Accelerator Pump Return Spring b - Pump Well Figure 10. Installing Accelerator Pump 392-H a - Check Ball b - Strainer c - Retainer Clip Figure 9. Installing Check Ball, Strainer, and Retainer Clip 392-H 90-95693 485 EXHAUST SYSTEM - 5A-21 Air Horn Assembly IMPORTANT: Accelerator pump assembly MUST BE installed correctly. If pump assembly is installed incorrectly, top of pump assembly will contact air horn casting. 1. If acceleraior pump assembly was removed from pump lever, secure pump assemblv to pump lever with washer and retainer clip, as shown in Figure 11. 2. Inserl pumpshaftand lever assembly (and washer) in:oair horn: then, align indexed hole in pump lever with shafl and lever assemblv and slide shaft all-the-way into lever so that shoulder on shaft is hitting lever. Tighten set screw securelv. (Figure 12) 18156 a - Accelerator Pump Assembly b - Retainer Clip c - Pump Lever Figure 11. Securing Accelerator Pump Assembly to Pump Lever 16943 a - Pump Lever b - Set Screw c - Pump Shaft and Lever Assembly d - Washer e - Air Horn a - Needle Seat b - Gasket c - Screwdriver Figure 13. Installing Needle Seat and Gasket IMPORTANT: Float needle and needle seat are factory matched and tested and should be replaced as a set only. 3. Install need e seat and gasket, using appropriate width screwdriver. (Figure 13) 4. Place needle assembly in needle seat. (Figure 14) 5. Install baffle. (Figure 15) 6. Place new gasket on air horn. (Figure 16) 7. Install float assemblv and hinge pin. (Figure 17) Pivot float assemblv up-and-down on hinge pin to ensure it moves freely. a - Needle Assembiy b - Needle Seat Figure 14. Installing Needle Assembly Figure 12. Installing Accelerator Pump Assembly and Pump Shaft and Lever Assembly 4C-22 - FUEL SYSTEM 90-95693 485 8. Place air horn on float bowl, making sure accelerator pump is correctly positioned in fuel well. Lower air horn straight down to install. (Figure 18) 9. Insta.I seven short and one longair horn attaching screws. Tighten screws evenly and securelv. (Figure 19) a - Baffle Figure 15. Installing Baffle a - Gasket Figure 16. Installing Air Horn Gasket a - Air Horn b - Float Bowl Assembly Figure 18. Carefully Installing Air Horn a - Float Assembly b - Float Hinge Pin 16922 Figure 17. Installing Float Assembly and Hinge Pin a - Seven Short Screws b - One Long Screw Figure 19. Installing Air Horn Attaching Screws 90-95693 485 EXHAUST SYSTEM - 5A-23 a - Choke Rod b - Choke Lever and Collar Assembly Figure 20. Installing Choke Rod l(). Place end of choke rod in choke lever and collar assemblv. (Figure 20) 11. Place idle cam on choke rod. (Figure 21) 12. Secure idle cam (with choke rod installed on cam) on float bowl assembly, using screw. (Figure 22) Check that cam is free lo move without binding. 16940 a - Idle Cam b - Choke Rod Figure 21. Installing Idle Cam 4C-24- FUEL SYSTEM a - Screw b - Idle Cam c - Choke Rod Figure 22. Securing Idle Cam to Float Bowl Assembly a - Accelerator Pump Rod b - Pump Shaft and Lever Assembly Figure 23. Installing Accelerator Pump Rod 90-95693 485 13. Place accelerator pump rod (end with ear) in hole in pump shaft and lever assembly. (Figure 23) 14. Insert remaining end of accelerator pump rod into hole in throttle lever and secure with retainer clip. (Figure 24) 16927 a - Accelerator Pump Rod b - Throttle Lever c - Retainer Clip Figure 24. Securing Accelerator Pump Rod to Throttle Lever Choke Housing Assembly IMPORTANT: Not all MerCarb carburetors are equipped with choke housing gasket. This gasket is not necessary for choke housing installation; therefore, if replacement gasket is not available, choke housing may be installed on air horn assembly without gasket. 1. Place new choke housing gasket (if equipped) in position on air horn making sure that, when installing choke housing assembly, locating pin on housing inserts into hole in gasket. (Figure 25) 2. Secure choke housing assembly to air horn with two attaching screws. (Figure 26) Tighten screws securely. 3. Fasten choke lever to choke shaft assembly with screw, as shown in Figure 26. 4. Place choke cover on choke housing. Be sure hook on end of heating coi. engages with choke lever. Rolate choke cover until alignment marks (madeat disassembly) lineup. a - Gasket b - Choke Housing Assembly Gasket Locating Pin Figure 25. Installing Choke Housing Assembly Gasket 384-H a - Choke Housing Assembly b - Choke Housing Assembly Attaching Screws c - Choke Lever d - Choke Lever Screw Figure 26. Installing Choke Housing Assembly and Choke Lever Assembly to Air Horn 5. Secure choke cover with three screw sand retainers (Figure 27). being sure ground terminal is fastened under bollom screw. 90-95693 485 FUEL SYSTEM - 4C-25 13498490 4501 13498490 4501 a - Screws b - Retainer c - Choke Cover Figure 27. Installing Choke Cover :-26 - FUEL SYSTEM 90-95693 485 SECTION 4 - FUEL SYSTEM PART D - ROCHESTER 4 BARREL INDEX Page Identification 4D-1 Replacement Parts Warning 4D-1 Torque Specifications 4D-2 Tools 4D-2 Specifications 4D-3 Descriptions 4D-7 Precautions 4D-7 Important Service Information 4D-8 4MC Carburetor 4D-8 Filler Blocks 4D-9 Maintenance 4D-9 Flame Arrestor 4D-9 Air Intake Hose 4D-11 Fuel Filter 4D-11 Adjustments 4D-12 Accelerator Pump 4D-12 Air Valve Dashpot 4D-13 Air Valve Spring Windup 4D-13 Float Level 4D-14 Choke Coil Rod 4D-15 Vacuum Break 4D-15 Electric Choke Adjustment (4MC Carburetor) 4D-16 Preliminary Idle Speed and Mixture 4D-17 Final Idle Speed and Mixture 4D-17 Repair 4D-18 Removal 4D-18 Installation 4D-19 Disassembly 4D-22 Electric Choke (4MC Carburetors) 4D-22 Air Horn 4D-22 Float Bowl 4D-24 Float Weight 4D-27 Throttle Body 4D-27 Cleaning and Inspection 4D-27 Reassembly 4D-28 Throttle Body 4D-28 Float Bowl 4D-29 Air Horn 4D-32 Electric Choke (4MC Carburetors} 4D-36 IDENTIFICATION 04886 REPLACEMENT PARTS WARNING Electrical, ignition and fuel system components on your MerCruiser are designed and manufactured to comply with U.S. Coast Guard Rules and Regulations to minimize risks of fire and explosion. Use of replacement electrical, ignition or fuel system components, which do not comply with these rules and regulations, could result in a fire or explosion hazard and should be avoided. TORQUE SPECIFICATIONS Fastener Location Lbs. Ft. (N.m) Lbs. In. (N.m) Carburetor to Manifold 132 (15) Fuel Line To Carburetor 18 (24) Fuel Inlet Filter Nut 18 (24) TOOLS MERCURY MARINE SPECIAL TOOLS 91-36392 Universal Carburetor Gauge 91-59339 Tachometer KENT-MOORE TOOL GROUP 1600 EXECUTIVE DRIVE JACKSON, MICHIGAN 49203 TEL. (517) 788-6210 J9789-118 Carburetor Stand J22769 Needle Valve Seat Remover WAGNEF NSTRUMENTS P.O. BOX .217 GREENWICH, CT. 06836 (203) 869-9681 Model G.D. 150 Gram Scale (With Round Tip) BORROUGHS TOOL & EQUIPMENT CORP. 2429 N. BURDICK ST. KALAMAZOO, MICH. 49007 (616) 345-5163 BT-8128 B Float Scale BT-8420 A Float Level Gauge TORX® SCREWDRIVERS Later Rochester Quadrajet carburetors will have a "star" shaped socket in the head of the screw. A TORX® screwdriver must be used on this type of screw. The three sizes used are #9, #20 and #25. 4C-2 - FUEL SYSTEM 90-95693 485 SPECIFICATIONS Model (Serial Number) Carb Type (Note 1) Mercury No. (Manufacturer No.) Primary Jet Size Primary (Secondary) Metering Rods Hanger (Note 2) MCM 228 (5069430 and Below) Rochester 4MV 1347-6427 (17057282) .069 In. .042 In. (DE) F MCM 228 (5069431-6021783) Rochester 4MV 1347-7361 (17059292) .069 In. .042 In. (DE) F MCM 228R (6021784 and Above) Rochester 4MV 1347-8296 (17080565) .069 In. .042 In. (DE) F MIE 228 (5069430 and Below) Rochester 4MV 1347-6438 (17057283) .067 In. .036 In. (DL) K MIE 228 (5067431-6040745) Rochester MV 1347-7364 (17059291) .067 In. .036 In. (DL) K MIE 228 (6040746 and Above) Rochester 4MV 1347-8290 (17080564) .067 In. .036 In. (DL) K MIE 230 (All) Rochester 4MV 1347-8290 (17080564) .067 In. .036 In. (DL) K MIE 255 (4924564 and Below) Rochester 4MV 1347-5732 (17044291) .069 In. .036 In. (CH) P MIE 255 (4924565-5195908) Rochester 4MV 1347-7062 (17057295) .069 In. .036 In. (CH) P MIE 255 (5195909-5907067) Rochester 4MV 1347-7365 (17059289) .069 In. .036 In. (CH) P MIE 255 (5907068 and Above) Rochester 4MV 1347-8289 (17080562) .069 In. .036 In. (CH) P MCM 260 (5060805 and Below) Rochester 4MV 1347-6492 (17057298) .068 In. .041 In. (DE) D MCM 260 (5060806-6024393) Rochester 4MV 1347-7362 (17059288) .068 In. .041 In. (DW-DE) D NOTES: 1. Rochester Quadrajets are 4MV or 4MC type. The "V" or "C" designates choke type, NOT bore size. This information supercedes all previous service bulletins and service information. 2. Hanger size may vary from this chart. Install same size hanger which was removed from the carburetor. 9C-95693 485 FUEL SYSTEM - 4D-3 Model (Serial Number) Carb Type (Note 1) Mercury No. (Manufacturer No.) Primary Jet Size Primary (Secondary) Metering Rods Hanger (Note 2) MCM 260R (6024394 and Up) Rochester 4MV 1347-8292 (17080561) .068 In. .041 In. (DW-DE) D MIE 260 (All) Rochester 4MV 1347-8289 (17080562) .069 In. .036 In. (CH) P MCM 330 (5027230 and Below) Rochester 4MV 1347-6493 (17057287) .069 In. .042 In. (DB) F MCM 330 (5027231-6083144) Rochester 4MV 1347-7363 (17059290) .069 In. .042 In. (DB) F MCM 330 (B-W) (6083145 and Above) Rochester 4MV 1347-8291 (17080563) .069 In. .042 In. (DB) F MIE 330 (5226384 and Below) Rochester 4MV 1347-6493 (17057287) .069 In. .042 In. (DB) F MIE 330 (5226385 and Above) Rochester 4MV 1347-7366 (17059287) .069 In. .042 In. (CL) F MCM 370/400/400 Cyclone (All) Rochester 4MV 1347-7298 (17059280) .068 In. .041 In. (DA) F MCM 488R (All) Rochester 4MC 1347-8460 (17081299) .066 In. .036 In. (CZ-DE) K MIE 340 (All) Rochester 4MV 1347-8288 (17080560) .069 In. .042 In. (CL) F NOTES: 1. Rochester Quadrajets are 4MV or 4MC type. The "V" or "C" designates choke type, NOT bore size. This information supercedes all previous service bulletins and service information. 2. Hanger size may vary from this chart. Install same size hanger which was removed from the carburetor. 4D-4 - FUEL SYSTEM 90-95693 485 UNIT OF MEASUREMENT in. (mm) MCM CARBURETOR ADJUSTMENT SPECIFICATIONS (Note 1) Engine Model MCM 228 MCM 260 MCM 330 MCM 370/400 400 Cyclone MCM 488 Make & Model Rochester 4MV Rochester 4MC Carb. Manufacturer Number 17059292 17057282 17080565 17059288 17057298 17080561 17059290 17057287 1708C563 17059288 17059280 17081299 Float Level 15/64 (5.9) (Note 2) Pump Rod Hole Location Irner Accelerator Pump (Note 3) 23/64 (9.1) Air Valve Dash Pot (Air Valve Rod) .025 (.64) Vacuum Break .080 [5/64 (2.0)] .190 [3/16 (4.8)] Air Valve Spring Wind Up 3/8 Turn 70-90 Gr. 1/2 Turn 70-90 Gr. 1/2 Turn 80-95 Gr. 5/8 Turn 70-90 Gr. 1/4 Turn 40-50 Gr. Choke Coil Rod (Note 5) Top of Rod Even With Bottom of Hole (Note 4) Idle Mixture Screw Preliminary Setting 2-3 Turns Float Weight (Max) 9.88 Gr. NOTES: 1. All measurements are ± 1/64" (0.4mm). Information contained in this chart supercedes all service bulletins printed in 1984 and earlier. 2. If fuel inlet needle is spring loaded: Float lever must just touch needle ball. Do not push down on ball: float level is 1/4" (6.4mm). Solid needle models: float level is 3/8" (9mm). 3. Accelerator pump measurement taken from flame arrestor surface to pump stem with throttle plates closed. 4. Refer to figure 16 or 17 in 'Adjustments" in this section for electric choke adjustment on the4MC carburetor. 5. Choke valve must be closed, choke rod in bottom of choke lever slot, and choke coil rod pushed down to end of travel. 90-95693 485 FUEL SYSTEM - 4D UNIT OF MEASUREMENT in. (mm) MIE CARBURETOR ADJUSTMENT SPECIFICATIONS (Note 1) Engine Model MIE 228 MIE 230 MIE 255 MIE 260 MIE 330 MIE 340 Make & Model Rochester 4MV Carb. Manufacturer Number 17059291 17057283 17080564 17080564 17059289 17044291 17080562 17057295 17080562 17059287 17057287 17080560 Float Level 15/64 (5.9) Pump Rod Hole Location Inner Accelerator Pump (Note 2) 23/64 (9.1) Air Valve Dash Pot (Air Valve Rod) .025 (.64) Vacuum Break .080 [5/64 (2.0)] Air Valve Spring Wind Up 3/8 Turn 75-85 Gr. 3/8 Turn 60-75 Gr. 3/8 Turn 75-85 Gr. 3/8 Turn 70-90 Gr. 3/4 Turn 30-95 Gr. Choke Coil Rod (Note 3) Top of Rod Even With Bottom of Hole Idle Mixture Screw Preliminary Setting 2-3 Turns Float Weight (Max) 9.88 Gr. NOTES: 1. All measurements are ± 1/64" (,4mm). Information contained in this chart supercedes all service bulletins printed in 1984 and earlier. 2. Accelerator pump measurement taken from flame arrestor surface to pump stem with throttle plates closed. 3. Choke valve must be closed choke rod in bottom of choke lever slot, and choke coil rod pushed down to end of travel. 4D-6- FUEL SYSTEM 90-95693 485 DESCRIPTION The4MV and 4MCQuadrajets are4 barrel,2 stage carburetors. Both the 4MV and 4MC are of the same design, the only real difference being in the choke operation. The 4MV has a manifold mounted choke thermostat housing, and a link rod attaching the thermostat spring to the carburetor choke linkage. The 4 MC has the choke thermostat housing mounted directly on the airhorn of the carburetor. The thermostat spring is hooked directly to the carburetor choke linkage. The Quadrajet carburetor has 2 stages of operation. The primary (fuel inlet) side has small bores with a triple venturi set-up equipped with plain tube nozzles. Its metering principles are similar to the most plain tube carburetors which use the venturi principle. The triple venturi stack up. plus smaller primary bores, give a more stable and finer fuel control in idle and economy ranges of operation. Fuel metering in primarv side is accomplished with tapered metering rods positioned by a manifold vacuum responsive piston. The secondary side has 2 very large bores which have greatlv increased air capacity to meet present day and future engine demands. The air valve principle is usee in the secondarv side for metering control and supplements fuel flow from the primary bores. Using the air valve principle, fuel is metered in direct proportion to air passing thru the secondarv bores. The fuel reservoir is centrally located to avoid problems of fuel slosh causing engine turn cut-out and delayed fuel to carburetor bores. The float system uses a single float pontoon for ease in servicing the unit. PRECAUTIONS FUEL SYSTEM - 4B-7 90-95693 485 IMPORTANT SERVICE INFORMATION 4MC CARBURETOR MERCURY NUMBER, 1347-9142 (Rochester Number 17083522) IMPORTANT: The MCM 190MR 4MC carburetor 17083522 supercedes the original 488R 4MC carburetor 17081299. There were several changes made on the 17083522 carburetor that must be addressed. 1. \lodifving (1,083522) Rochester carburetor for use on MCM 488. a. Before installing the (17083522) carburetor on MCM 488 remove and discard the choke pull-off lever, spacer and screw as shown in Figure 1. These parts must be removed because they will hit the 10^ wedge when installing the carburetor. a - Throttle Shaft b - Spacer Remove and Discard c - Lever d - Screw Figure 1. Modifying 17083522 Carburetor 4D-8 - FUEL SYSTEM 90-95693 485 2. The 17083522 Rochester carburetor has a nozzle deflector IMPORTANT: When installing the 17083522 installed in the float bowl (Figure 2) Rochester carburetor on a 488R with a 10° wedge the nozzle deflector can be used. FILLER BLOCKS 1. There are 2 tvpes of filler blocks used. Refer to Figure 3. MAINTENANCE FLAME ARRESTOR 18500 a - Nozzle Deflector Figure 2. Nozzle Deflector Installed a - Short Filler Block Used on All 4MV V-8 Carburetors b - Long Filler Block Used on 4MC 488R Carburetors Figure 3. Types of Filler Blocks NOTICE Refer to "Precautions", in this section, BEFORE proceeding. IMPORTANT: There has been 3 styles of Flame Arrestors used on the Quadrajet carburetor. The 3 styles are depicted in Figures 1, 2, or 3. Locate the style you are servicing and follow proper service instructions. 1. Remove (in the following order): Figure 1 a. Nut b. Sealing 'ft asher c. Hose Clamp(s) and Crankcase Ventilation Hose(s) d. Flame Arrestor Lift from carburetor 2. Clean and Inspect: a. Clean flame arrestor by blowing it out with compressed air. b. Clean crankcase ventilation hose c. Inspect crankcase ventilation hose for cracks or deterioration, and replace if neccessry. a - Nut b - Washer 3. Install (in the following order): Figure 1 a. Flame Arrestodr - Place on Carburetor c - Clamps b. Crankcase Ventilation Hose(s) and Hose d - Crankcase Ventilation Hoses(s) Clamp(s) e - Flame Arrestor c. Sealing Washer Figure 1. Flame Arrestor Only d. Nut - Tighten Securelv 90-95693 485 FUEL SYSTEM - 4B-9 1. Remove (in the following order): Figure 2 a. Nut b. Sealing Washer c. Carburetor Cover d. Hose Clamps and Crankcase Ventilation Hoses - From Flame Arrestor and Rocker Arm Covers e. Flame Arrestor - Lift from Carburetor 2. Clean and Inspect: a. Clean flame arrestor in solvent and blow dry with compressed air b. Clean crankcase ventilation hoses c. Inspect crankcase ventilation hoses for cracks or deterioration, and replace if necessarv. 3. Install (in the following order): Figure 2 a. Flame Arrestor - Place on carburetor b. Crankcase Ventilation Hoses and Hose Clamps - To Flame Arrestor and Rocker Arm Covers c. Carburetor Cover d. Sealing Washer e. Nut - Tighten Securely. b - Washer c - Carburetor Cover d - Clamps e - Crankcase Ventilation Hoses f - Flame Arrestor Figure 2. Flame Arrestor with Carburetor Cover a - Nut b - Washer c - Step Washer d - Rubber Washer e - Nut (Early Models) f - Washer (Early Models) g - Flange Nut (Later Models) h - Flame Arrestor i - Air Silencer j - Screws Figure 3. Flame Arrestor with Air Silencer 1. Before removing Air Silencer assembly, loosen clamp and remove air intake hose from air silencer. 2. Remove (in following order): Figure 3 a. Nut b. Washer c. Step 'Washer d. Rubber Washer e. Nut or Flange Nut f. Washer (Early Models) g. Hose Clamps and Crankcase Ventilation Hoses 3. Remove Air Silencer assembly from carburetor as an assembly. Flip air silencer over and remove4 screws w hich hold air silencer together. Remove Flame Arrestor. 4. Clean and Inspect: a. Clean Flame Arrestor by blowing it out with compressed air. b. Clean crankcase ventilation hoses. c. Inspect crankcase ventilation hoses for cracks or deterioration. replace if necessary. 5. Reassemble Air Silencer assembly with 4 screws - Tighten securely. 6. Install (in following order): a. Air Silencer to Carburetor b. Crankcase Ventilation Hoses and Clamos c. Washer (Early Models) d. Nut or Flange Nut e. Rubber ^ asher f. Step Washer g. Washer h. Nut - Tighten Securely 7. Install air intake hose and clamp to air silencer and tighten clamp securely. 4C-10 - FUEL SYSTEM 90-95693 485 AIR INTAKE HOSE 1. Remove; Figure 1 Air intake hose (attached to carburetor air silencer on some models) must be positioned and secured so that inlet is a minimum of 12" (305mm) above bottom of bilge (to prevent it from picking up water) and in an area where it will not pick up debris. DO NOT place inlet in storage bin. as small articles placed in bin mav get sucked into inlet. DO NOT connect inlet to outside of boat, as water vapor/mist/splash may be drawn into inlet. Up to 3 ft. (914mm) of 5" (127mm) ID hose can be added to end of air intake hose, if necessary to allow proper positioning of hose inlet. FUEL FILTER NOTICE Refer to "Precautions", in this section, BEFORE proceeding. • Fuel line from fuel inlet filter nut • Fuel inlet filter nut • Large gasket • Filter • Spring • Small gasket - From inside filter nut a - Fuel Line b - Fuel Inlet Filter Nut c - Gasket (Large) d - Gasket (Small) e - Filter f - Spring Figure 1. Changing Fuel Filter 2. Clean filter nut and spring. 3. Install the following; Figure 1 • Spring - Place in carburetor body • Filter - Open end to inlet filter nut • Small gasket - Place inside filter nut • Large gasket - Place over filter nut • Fuel inlet filter nut - Tighten to specifications • Fuel line - Tighten to specifications 90-95693 485 EXHAUST SYSTEM - 5A-11 ADJUSTMENTS 3. Close throttle valves completely and measure from flame NOTICE arrestor mounting surface to top of pump plunger stem. Refer to "Precautions", in this section, BE( Figure 3) FORE proceeding. ACCELERATOR PUMP 1. Back out idle stop screw until it no longer contacts throttle lever. (Figure 1) 18098 18207 a - Flame Arrestor Mounting Surface b - Pump Plunger Stem Figure 3. Measuring Pump Plunger Height 4. hile supporting lever, bend tip of pump lever to obtain specified dimension. (Figure 4) a - Idle Stop Screw b - Throttle Lever Figure 1. Backing Out Idle Stop Screw 2. Pump rod must be ir inner hole of lever. (Figure 2) a - Tip of Pump Lever b - Support as Shown a - Pump Rod b - Inner Hole Figure 2. Pump Rod Location Figure 4. Adjusting Pump Plunger Height 4C-12 - FUEL SYSTEM 90-95693 485 AIR VALVE DASHPOT 1. Seat vacuum break diaphragm and close air valve completely. Bend rod to adjust gap to specifications. (Figure 5) a - Carburetor Casting b - Gram scale c - Contact Area of Arm on Air Valve d - Rotate Figure 6. Checking Air Valve 2. To adjust spring windup. hold tension spring screw and loosen alien head screw . (Figure 7) 3. Adjust tension and retighten alien screw securelv. (Figure 7) a - Push in Completely b - Bend Here to Adjust c - Specified Gap d - Fully Closed Figure 5. Adjusting Dashpot Link Rod. AIR VALVE SPRING WINDUP 1. Rotate gram scale until air valve begins to open, check scale reading. (Figure 6) a - Increase b - Decrease c - Loosen Allen Heac Screw Figure 7. Adjusting Air Valve 90-95693 485 EXHAUST SYSTEM - 5A-13 FLOAT LEVEL 1. Start engine to fill float bowl, run at idle and insert float gauge into hole next to flame arrestor stud. (Figure 8) 18210 a - Gauge Hole b - Gauge (BT-8420A) Figure 8. Installing Float Gauge 2. Tap float gauge down lightly to assure free movement. (Figure 9) a - Read Here Figure 10. Checking Float Level with Gauge 4. If float requires adjustment hold hinge p:n firmly, turn carburetor upside down and measure from casting surface to toe of float with universal carburetor gauge. Check specifications. (Figure 11) 5. Bend at float arm notch and adjust to specification. 18205 a - Gauge Figure 9. Tapping Float Gauge 3. Take gauge reading at top of carburetor casting. (Figure JO) a - Hinge Pin b - Universal Carburetor Gauge Figure 11. Adjusting Float 4C-14 - FUEL SYSTEM 90-95693 485 CHOKE COIL ROD 3. Bend rod to adjust. (Figure 14) 1. Push choke coil rod down. (Figure 12) 18213 a - Vacuum Break Choke Lever b - Choke Coil Rod Figure 12. Pushing Choke Rod Down 2. Choke coil rod lop must be even with bottom of hole in vacuum break choke lever. (Figure 13) Figure 14. Bending Choke Coil Rod VACUUM BREAK 1. Seat vacuum break control diaphragm. (Figure 15) a - Vacuum Break Control Diaohragm Figure 15. Seating Vacuum Break Control Diaphragm 18213 a - Top of Rod b - Bottom of Hole Figure 13. Checking Choke Rod Adjustment 90-95693 485 FUEL SYSTEM-4C-15 2. Rotate vacuum break choke lever counterclockwise until tang contacts vacuum break rod. Choke rod must be at bottom of choke shaft lever slot. (Figure 16) a - Tang b - Choke Rod c - Vacuum Break Rod Figure 16. Rotating Choke Lever 3. Bend tang as necessary to obtain specified choke valve gap. (Figure 17) ELECTRIC CHOKE ADJUSTMENT (4MC CARBURETORS) 1. Adjusting choke on 488R engines with 4MC carburetor. (Figure 18) a - Last Index Mark on Choke Housing on Lean Side b - Index Mark on Choke Cover c - 1/4" (6mm) Figure 18. Index Mark V«" (6mm) Past the Last Lean Mark on Choke Housing a - Tang b - Specified Gap Figure 17. Checking Vacuum Break and Unloader Adjustment 4C-16 - FUEL SYSTEM 90-95693 485 PRELIMINARY IDLE SPEED and MIXTURE Carburetor should be set so that engine idles smoothly, with Initial start setting, make final adjustments with engine running. 1. Turn idle stop screw until contact with throttle lever. 18098 a - Idle Stop Screw b - Throttle Lever Figure 19. Idle Stop Screw and Throttle 2. Turn idle needle? until LIGHTLY seated then back out 2 to 3 turns. a - Idle Needles Figure 20. Idle Mixture Needles IMPORTANT: Do not turn idle mixture screws tightly against seat, as damage to seat and/or needle may result. FINAL IDLE SPEED and MIXTURE IMPORTANT: Boat MUST BE in the water and engine at normai operating temperature to accu rately check and adjust idle speed and mixture. boat in the water, engine at normal operating temperature and drive unit in forward gear. To adjust idle speed and mixture, proceed as follows: IMPORTANT: DO NOT attempt to compensate for other engine problems (incorrect ignition timing, faulty ignition components, low compression, vacuum leaks, etc.) with carburetor adjustments. This will only cover the problem, which must be corrected if engine is to achieve maximum fuel economy and performance. 1. Connect a shop tachometer to engine. IMPORTANT: DO NOT turn idle mixture needles (Figure 20) tightly into seat, as damage to needle and/or seat may result. 2. If a new or rebuilt carburetor has been installed, turn each idle mixture needle (Figure20) until it LIGHTLY contacts seat, then back out 2 to 3 turns. This will provide a sufficient setting to allow starting the engine. 3. Start engine and run at 1300 RPM until engine reaches normal operating temperature. 4. With boat in open water, place remote control in forward gear, idle position. 5. Disconnect throttle cable brass barrel from anchor stud. BE SURE NOT TO LOSE SPACER ON ANCHOR STUD. 6. Adjust idle speed adjustment screw (Figure 19) to obtain specified RPM. 7. ith engine runningat specified RPM. adjust idle mixture needles (Figure 20). as follows: a. Turn idle mixture needle inward (clockwise) until the engine speed begins to drop due to lean mixture. b. Turn idle mixture screw outward (counterclockwise) until the speed begins to drop due to a rich mixture. c. Turn screw inward to a point between these two extremes to obtain maximum engine smoothness and RPM. d. Repeat procedure with other needle. e. Readjust idle speed adjusting screw, if necessary, to obtain specified RPM. IMPORTANT: Refer to "Section 2" for throttle cable installation and adjustment. 90-95693 485 EXHAUST SYSTEM - 5A-17 18197 18197 REPAIR NOTICE Refer to "Precautions", in this section, BEFORE proceeding. IMPORTANT: Carburetor malfunctions are, in many cases, caused by the presence of dirt, water or other foreign matter in carburetor. To aid in diagnosis, carefully remove carburetor from engine without draining fuel from bowl. Contents of fuel bowl may, then, be inspected for contamination as carburetor is disassembled. REMOVAL 1. Remove flame arrestor. 2. Disconnect choke spring rod if working on 4MY carburetor. (Figure 1) d 18202 a - Choke Rod b - Clip Figure 1. Removing Choke Spring Rod (4MV Carburetor) a - Fuel Line Figure 3. Removing Fuel Line 3. Disconnect sigh: tube (if equipped). (Figure 2) 18203 a - Sight Tube Figure 2. Removing Sight Tube IMPORTANT: Place a clean cloth in bores of car buretor to prevent dirt and foreign material from falling into bores. 4. Turn off fuel supply at the fuel tank. 5. Disconnect fuel line. (Figure 3) 4D-18- FUEL SYSTEM 90-95693 485 6. Disconnect throttle cable. (Figure 4) IMPORTANT: Place a clean cloth over intake manifold opening to prevent dirt orforeign material from entering manifold. 10. Remove old gasket from carburetor and manifold. a - Throttle Cable Figure 4. Removing Throttle Cable 7. Disconnect cable end guide. (Figure 5) a - Bolts b - Nuts c - Cable Bracket Figure 6. Removing Carburetor INSTALLATION 1. Install new gasket onto manifold. 2. Install carburetor and throttle bracket and torque to specifications. (Figure 7) a- Cable End Guide Figure 5. Removing Cable End Guide 8. Remove electric choke wires if working on a 4.V1C model carburetor. 9. Remove retaining nuts and bolts, remove carb.iretor and cable bracket. (Figure 6) a - Mounting Bolts b - Nuts c - Throttle Bracket Figure 7. Installing Carburetor 90-95693 485 FUEL SYSTEM - 4C-19 3. Connect fuel line and torque to specifications. (Figure 8) 5. Connect choke link and install retaining clip, if working on 18197 a - Fuel Line Figure 8. Connecting Fuel Line 4MY carburetor. (Figure 10) 18202 a - Choke Link 4. Connect fuel sight tube. (Figure 9) b - Clip Figure 10. Connecting Choke Spring Rod (4MV Carburetor) 6. Connect electric choke wires if working on 4MC carburetor. T. To install throttle cable refer to "Section 2. Removal. Installation, and Alignment". 8. Install flame arrestor and tighten securely. 9. Reconnect battery cables to battery. 10. Start engine and check for gasoline leaks. If leaks exist. STOP ENGINE IMMEDIATELY and recheck connections. 11. Adjust idle speed and idle mixture, as outlined under "Adjustments" preceding. a - Sight Tube Figure S. Connecting Sight Tube 18203 4C-20 - FUEL SYSTEM 90-95693 485 1 - Air Horn Assemoly 2 - Screw 3 - Hanger 4 - Metering Rod. secondary - Screw 6 - Screw 7 - Screw 8 - Lever 9 - Roll Pin - Pump 11 - Spring 12 - Needle and Seat 13 - Gasket 14 - Pull Clip - Gasket 16 - Metering Rod, primary 17 - Jet, primary 18 - Float Assembly 19 - Pin hinge - float - Lever, intermediate choke 21 - Rod 22 -Clip 23 - Rod 24 -Clip - Screw 26 - Control 27 - Hose 28 - Power Piston 29 - Retainer, power piston - Retainer pump discharge ball 31 - Ball pump discharge 32 - Spring, power piston 33 - Insert, float bow 34 - Float Bowl - Screw, idle stop 36 - Spring, idle stop screw 37 - Spring, filter nut 38 - Filter, fuel inlet 39 - Nut. fuel inlet - Gasket 41 - Gasket 42 - Rod 43 - Throttle Body 44 - Idle Needle - Screw Figure 11. Exploded View - 4MV/4MC Quardrajet (Rochester Carburetor) FUEL SYSTEM - 4C-21 90-95693 485 2. Remove choke lever screw. (Figure 14) 3. Remove choke housing assembly. (Figure 14) 1 - Choke Housing 2 - Screw 3 - Lever 4 - Screw 5 - Choke Cover and Thermostat 6 - Retainer 7 - Terminal a - Screw - Choke Lever 8 - Lockwasher b - Choke Lever 9 - Screw c - Screws - Choke Housing Assembly d - Gasket - If Equipped (Not Visible) Figure 12. Exploded View of Electric Choke Used on e - Choke Housing Assembly 4MC Carburetor Figure 14. Removing Choke Lever and Choke Housing Assembly DISASSEMBLY Air Horn IMPORTANT: Place carburetor on a holding fix-1. Remove vacuum pump rod clip and rod. (Figure 15) ture to prevent throttle valve damage. 384-H Electric Choke (4MC Carburetors Only) 1. Remove choke cover. ; Figure 13) a - Rod Clip Figure 15. Removing Clip a - Screws b - Retainers c - Choke Cover Figure 13. Removing Choke Cover 384-H a - Rod Figure 16. Removing Vacuum Pump Rod 18167 4C-22 - FUEL SYSTEM 90-95693 485 2. Remove choke shutter clip and rod. (Figures 17 and 18) a - Roll Pin (Not Shown) b - Pump Lever c - Rod Figure 19. Removing Accelerator Pump Lever 3. Drive roll pin back and remove accelerator pump lever and rod. (Figure 19) 4. Remove screw, secondary metering rods and hanger. (Figure 20) a - Clip Figure 17. Removing Choke Rod Clip a - Rod Figure 18. Removing Choke Rod a-Screw b - Metering Rods c - Hanger Figure 20. Removing Metering Rods and Hanger 90-95693 485 FUEL SYSTEM - 4C-23 5. Remove air horn screws and air horn. (Figures 21 ar.d 22) 1- Remov e pump plunger, return spring and gasket. (Figure 23) 18112 a - Air Horn Screws Figure 21. Air Horn Screws a - Air Horn Figure 22. Removing Air Horn Float Bowl 18192 a - Pump Plunger b - Return Spring c - Gasket Figure 23. Removing Gasket and Accelerator Pump 2. Remove insert block, power piston and spring. (Figure 24) NOTICE Refer to "Important Service Information", a - Insert Block b - Power Piston c-Spring when repairing a 4MC carburetor (Rochester NO. 17083522), BEFORE proceeding. Figure 24. Removing Insert Block and Power Piston 90-95693 485 4D-24- FUEL SYSTEM Remove fioai assemblv. needle, and retaining pin. (Figure 25) a - Solid Needle (1397-8548) b - Spring Loaded Needle (1397-8960) c - Spring Loaded Ball Figure 27. Types of Needles used in 488R Carburetor a - Float Assembly b - Needle c - Retaining Pin Figure 25. Removing Float and Inlet Needle IMPORTANT: 4MV carburetors will have a solid needle. (Figure 27) 4MC carburetors may have a spring loaded or solid needle. (Figure 27) It is important to install the same type of needle that was removed from the 4MC carburetors. 4. Remove fuel inlet seat and gasket. (Figure 26) 5. Remove primary metering jets, pump discharge check ball retainer and check ball. (Figure 28) a - Fuel Inlet Seat a - Primary Meterinq Jets b - Pump Discharge Retainer b - Gasket c-Check Ball (Not Visible) Figure 26. Removing Inlet Seat Figure 28. Removing Primary Jets and Retainer and Check Ball 9C-95693 485 FUEL SYSTEM -4D-25 Remove fuel inlet filter nut. gaskets, filter and spring. 6. Remove baffle. (Figure 29) 8. (Figure 31) a - Baffle Figure 29. Removing Baffle 7. Remove vacuum control assembly arid hose. (Figure 30) 9. Separate throttle body from float bow! and remove gasket. (Figure 32) a - Vacuum Control Assembly b - Hose Figure 30. Removing Vacuum Control a - Attaching Screws c - Gasket b - Throttle Body d - Float Bowl Figure 32. Removing Throttle Body 18177 4B-26 - FUEL SYSTEM 90-95693 485 Float Weight 1. Assemble float scale to instructions with scale. 2. Check float wight ic specifications. (Figure 33) IMPORTANT: Throttle body should not be disas sembled any further than shown. Throttle body is serviced as an assembly only. CLEANING and INSPECTION 1. Clean carburetor in immersion type cleaner. 2. Blow out passages with compressed air. Do not run drill thru passages. 3. Inspect for wear: • Idle mixture needles • Float needle and seat • Casting surfaces • All levers • Fast idle cam • Power piston • Accelerator pump seal 4. Check all valves for binding. 5. Check vacuum break unit for leaks. a. Depress plunger and seal hose connection. (Figures 1 and 2). — 18219 a - Float Scale b - Float Figure 33. Checking Float Weight 3. Replace float if il exceeds specifications. Throttle Body 1. Remove idle mixture screws and springs. (Figure 34) a - Screw b - Spring Figure 34. Removing Idle Mixture Screws 18185 a - Plunger b - Hose Connection Figure 1. Seating Plunger 90-95693 485 EXHAUST SYSTEM - 5A-27 Figure 2. Plunger Seated and Hose Connection Sealed b. Maintain seal on hose connection, plunger must remain seated. If plunger extends, replace unit. (Figure 2) IMPORTANT: The idle fuel pickup tubes have a smaller I.D. at the bottom than the top. Do not drill. 6. Clean idle fuel pickup tubes with a fine w ire (approx. .020" O.D.) and blow out all channels with compressed air. (Figure 3) 17307 a - Idle Fuel Pickup Tubes b - Channel Restrictions Figure 3. Cleaning Idle Passages IMPORTANT: If engine is experiencing a rough idle situation and cannot be smoothed out with idle adjustment screws, drill out the channel restrictions to .055", using a No. 54 drill. (Figure 3) Blow out channel with compressed air to clean out. Some later model carburetors already have this operation completed. REASSEMBLY Throttle Body NOTICE Refer to "Adjustments" for all adjustment procedures. IMPORTANT: Seat idle mixture screws lightly or damage to needles and seats will result. 1. Install idle mixture needles and springs unt.l lightly seated, then back out 2 or 3 turns. (Figure 1) a - Idle Mixture Needles and Springs Figure 1. Installing Idle Mixture Needles 2. Install new gasket and assemble throttle body to float bowl. Tighten securely. (Figure 2) a - Attaching Screws b - Throttle Body c - Gasket d - Float Bowl Figure 2. Installing Throttle Body 90-95693 485 4D-28- FUEL SYSTEM Float Bowl NOTICE Refer to "important Service Information", BEFORE proceeding. IMPORTANT: Place carburetor on a holding fixture to prevent damage to throttle valve. 1. Install baffle plate. (Figure 3) 18099 a - Baffle Plate Figure 3. Installing Baffle Plate 2. Install intermediate choke lever and vacuum break control bracket assembly. (Figure 4) a. Lsing choke rod. suspend intermediate choke lever in floal bowl cavitv so that flat sided hole aligns with hole in side of float bowl. a - Choke Rod b - Choke Lever c - Flat Sided Hole Figure 4. Installing Choke Rod and Lever 90-95693 485 b. Insert choke shaft on vacuum break control assembly to engage flat sided holeofchokelever, and secure with screw . Tighten securelv. (Figure 5) a - Choke Rod b - Choke Shaft c - Vacuum Break Control Assembly Figure 5. Installing Choke Rod to Vacuum Break 3. Install pump discharge check ball, retainer and primarv main metering jets. Tighlen securelv. (Figure 6) a - Check Ball (Not Shown] b - Retainer c - Primary Main Metering Jets Figure 6. Installing Check Ball, Retainer and Primary Jets IMPORTANT: Float needle and seat should be replaced as a set only. FUEL SYSTEM - 4C-29 b. I f a new float or needle and seat are used, bend float arm sliahtlv upward at notch for easier adjustment. (Figure 9)" 4. Install float needle seat and gasket. (Figure 7) 18104 a - Float Needle Seat b - Gasket Figure 7. Installing Needle Seat and Gasket 5. Installing float needle and float assemblv. a. Install pull clip onto needle. (Figure 8) a - Float b - Float Arm Notch Figure 9. Bending Float Arm Hook needle pull clip over edge of float arm closet to pontoon. (Figure 10) a - Pull Clip b - Float Arm Figure 10. Proper Installation of Pull Clip a - Pull Clip b - Needle 18105 Figure 8. Installing Pull Clip on Needle 90-95693 485 4C-30 - FUEL SYSTEM d. Install retaining pin into float arm and install float and 7. Install primary main metering rods in power piston hanger, needle into bowl. (Figure 11) and ccnnect spring as shown. (Figure 13) a - Float b - Needle c - Hinge Pin a - Power Piston Hanger b - Tension Spring c - Metering Rods Figure 11. Installing Float and Needle Figure 13. Installing Primary Metering Rods IMPORTANT: Top of hinge pin must extend above casting by .010" (.25mm) for good pin retention. 8. Install power piston assembly, guiding metering rod tips into main metering jets. (Figure 14) e. Check float adjustment (refer to "Adjustment" in this section). 6. Install power piston spring. (Figure 12) a - Power Piston Spring Figure 12. Installing Power Piston Spring a - Power Piston Assembly b - Metering Rod Tip in Main Metering Jet Figure 14. Installing Power Piston Assembly 90-95693 485 EXHAUST SYSTEM - 5A-31 Air Horn 9. Push power piston retainer down until flush with casting. (Figure 15) 1. Install new gasket and slide tab under power piston hanger. (Figure 18) a - Power Piston Retainer Figure 15. Seating Power Piston 10. Install filler block. (Figure 16) a - Power Piston Hanger b - Gasket Tab Figure 18. Proper Installation of Gasket 2. Install acceletor pump plunger. (Figure 19) a - Filler Block Figure 16. Installing Filler Block ll. Install accelerator pump plunger spring. (Figure 17) em 18172 a - Plunger Figure 19. Installing Accelerator Pump a-Spring Figure 17. Installing Pump Return Spring 90-95693 485 4B-32 - FUEL SYSTEM 3. Instai! air horn. (Figure 20) 5. Install secondarv metering rods into hanger with upper ends toward each other as shown. (Figure 23) 4. Install 9 attaching screws. Tighten securely in sequence as numbered. (Figure 21) a - Long b - Short c - Countersunk Figure 21. Attaching Screw Installation IMPORTANT: Hanger size may vary from specification chart. Manufacturer varies hanger size to make up differences :n carburetor castings. Always install the same size hanger as was removed from the carburetor. Difference in hangers is the hole location, (Figure 22", which affects secondary fuel metering. a - Hanger b - Metering Rods Figure 23. Installing Metering Rods 6. Install metering rods and hanger and secure with screw. Tighten securely. (Figure 24) a - Screw b - Metering Rods c - Hanger Figure 24. Installing Hanger Assembly a - Hole Location Changes Fuel Metering b - Richer c - Leaner Figure 22. Hanger Size 90-95693 485 EXHAUST SYSTEM- 5A-33 9. Press roll pin into place using a screwdriver. 7. Install pump lever rod. (Figure 25) a - Pump Lever Rod Figure 25. Instating Pump Lever Rod 8. Install rod into lever inner hole and place lever into casting mount. (Figure 26) a - Roll Pin Figure 27. Installing Roll Pin 10. Install bottom end of choke shutter rod inlo intermediate choke lever in float bowl. (Figure 28) a - Rod c-Inner hole b - Lever d - Casting Mount Figure 26. Locating Pump Lever Rod 4D-34- FUEL SYSTEM a - Choke Shutter Rod Figure 28. Install Choke Shutter Rod to Intermediate Choke Lever 90-95693 485 11. Install upper end of choke shutter rod into the choke blade 13. Instal rod into vacuum break arm and install clip. (Figure lever, insiali clip onto choke shutter rod. (Figure 29) 31) 14. Instali vacuum break hose onto carburetor fitting. (Figure 32) a - Fitting b - Hose Figure 32. Installing Vacuum Hose 15. Install vacuum break hose onto vacuum dashpol fitting. (Figure 33) a - Choke Shutter Rod b - Clip c - Choke Blade Lever Figure 29. Installing Upper End of Choke Shutter Rod 12. Install rod into air valve lever. (Figure 30) a - Rod b - Air Valve Lever Figure 3G. installing Air Valve Rod a - Hose b - Dashpot Fitting Figure 33. Installing Vacuum Hose to Dashpot a - Rod b - Vacuum Break Arm c - Clip Figure 31. Installing Rod to 3reak Arm 18193 90-95693 485 EXHAUST SYSTEM - 5A-35 ELECTRIC CHOKE (4MC CARBURETORS) 2. Install choke lever and screw. Tighten securely. 3. Install choke cover, retainers, lockwashers, and screws. Adjust choke to specifications. Tighten screws securely. 1. Install choke housing assembly. Tighten securely. a - Screw - Choke Lever d - Gasket - If Equipped (Not Visible) b - Choke Lever e - Choke Housing Assembly c - Screws - Choke Housing Assembly Figure 34. Installing Choke Housing and Lever a - Screws b - Retainer c - Choke Cover Figure 35. Installing Choke Cover 90-95693 485 4D-36- FUEL SYSTEM SECTION 4 - FUEL SYSTEM PART E - HOLLEY 4 BARREL INDEX Page Identification 4E~1 4E'1 Replacement Parts Warning 4E_2 Torque Specifications 4E"2 ToolsSpecifications 4E ~3 Descriptions 4E~3 Precautions 4E~4 Maintenance 4E~4 Flame Arrestor 4E~4 4E"5 Fuel Filters 4E_5 Choke InspectionAdjustments 4E~6 4E"6 Preliminary Float Adjustment 4E"6 Final Float AdjustmentAccelerator Pump 4E~6 4E"7 Choke Adjustment Preliminary Idle Speed and Mixture 4E-7 Final Idle Speed and Mixture 4E-8 Repair 4E~9 4E_9 Modifications 4E" 1 0 Removal Installation 4E-10 Disassembly 4E-10 Choke Housing 4E-10 Fuel Bowls and Metering Bodies 4E-11 Carburetor Body 4E-14 4E" 1 4 Throttle Body Cleaning and Inspection 4E-15 Reassembly 4E-16 Throttle Body 4E-16 Carburetor Body 4E-16 Fuel Bowls and Metering Bodies 4E-17 Choke Housing 4E-19 IDENTIFICATION a - Part Number b - "MOD" (440/460 Cyclone Only) Figure 1. Holley Part Number Location REPLACEMENT PARTS WARNING Electrical, ignition and fuel system components on your MerCruiser are designed and manufactured to comply with U.S. Coast Guard Rules and Regulations to minimize risks of fire and explosion. Use of replacement electrical, ignition or fuel system components, which do not comply with these rules and regulations, could result in a fire or explosion hazard and should be avoided. 90-95693 485 FUEL SYSTEMS - 4E-1 TORQUE SPECIFICATIONS Fastene FasteneFastene r rr Locatio LocatioLocatio n nn 440/460 Cyclone 475 Turbo Lbs. Ft. (N.m) Lbs. In. (N.m) Carburetor to Manifold 20 (27) 20 (27) Fuel Line To Carburetor 18 (24) 18(24) Fuel Inlet Filter Nut Securely TOOLS MERCURY MARINE SPECIAL TOOLS 91-59339 Tachometer 91-36392 Universal Carburetor Gauge BORROUGHS TOOLS AND EQUIPMENT 2429 N. BURDICK ST. KALAMAZOO. MICHIGAN 49007 (616)345-5163 BT8128B Float Gram Scale 4E-2 -FUEL SYSTEMS 90-95693 485 SPECIFICATIONS Engine Model 440/460 Cyclone 475 Turbo Make Holley Holley Model 4150 4150 Holley Part No. 4781 9022 Mercury Part No. 1393-8862 1374-1802 Main Primary Jets .84 .072 Main Secondary Jets .084 .094 Accelerator Pump .015 (,4mm) .015 (,4mm) Accelerator Pump Check Ball .015" (4mm) .015" (4mm) Float Adjustment Bottom of Sight Plug Hole ±1/32" (,8mm) Bottom of Sight Plug Hole ±1/32" (,8mm) Float Weight 15.6 Grams Max. 15.6 Grams Max. Choke Setting Index Marks Aligned Index Marks Aligned Preliminary Idle Mixture Setting 2 Turns 2 Turns DESCRIPTION The model 4150 is a 4 bore Holley carburetor with an electri-fuel bowls and the carburetor body, metering bodies are cally operated automatic choke. The Holley model 4150 is a located. The metering bodies contain the main jets, power dual feed, double pump carburetor. This means each fuel bowl valve, and the majority of the metered passages in the carburehas a seperate fuel inlet and there 2 accelerator pumps, one for tor. Both the primarv and secondary floats have an external the primary side and one for the secondary side. Between the float adjustment. 90-95693 485 FUEL SYSTEMS-4E-3 PRECAUTIONS MAINTENANCE Refer to "Precautions" in this section, BEFORE proceeding. FLAME ARRESTOR 1. Remove in the following order: Figure 1 a. Nut. b. Washer. (Not Shown) c. Hose clamps and crankcase ventilation hoses - From flame arrestor and rocker arm covers. d. Flame arrestor - Lift from carburetor 2. Clean and inspect: Figure 1 a. Clean flamearrestor by blowing it out with compressed air. b. Clean crankcase ventilation hoses. c. Inspect crankcase ventilation hoses for cracks or deterioration, replace if necessary. 3. Install in the following order: Figure 1 a - Nut a. Flame arrestor - Place on carburetor. b - Flame Arrestor b. Crankcase ventilation hoses and clamps - To flame c - Crankcase Ventilation Hoses arrestor and rocker arm covers. d - Clamps c. W'asher (Not Shown). d. Nut - Tighten securely, do not overtighten. Figure 1. Flame Arrestor 17584 5A-4 - EXHAUST SYSTEM 90-95693 485 FUEL FILTERS Refer to "Precautions", in this section, BEFORE proceeding. Carburetor inlet filters are located in float chamber assemblies behind fuel inlet fittings (Figure 2). To replace filters proceed as follows: 1. Remove fuel line from fuel inlet filter nuts. 2. Remove fuel inlet filter nut. gasket, filter and spring from each float chamber assembly. (Discard gasket and filter.) 3. Clean nuts and springs in solvent and drv with compressed air. 4. Install spring, new filter (with open end outward), gasket and fuel inlet filter nut into each float chamber assembly (in that order). Tighten nut securely. 5. Reconnect fuel line and tighten securelv. 6. Run engine and check for gasoline leaks. CHOKE INSPECTION The choke does not require any periodic maintenance: however. if a choke malfunction is suspected, the following should be done: 1. With engine off. remove flame arrestor. Open and close choke several limes, andcheckfor binding, loose or disconnected linkages, or oiher signs of damage. 3. If choke or linkage binds, sticks, or works sluggishly, clean with carburelor choke cleaner. Carefully follow directions on can. a - Fuel Line Fittings b - Fuel Filter Nut c - Filter Nut Gasket d - Filter e - Spring Figure 2. Fuel Inlet Filter 90-95693 485 FUEL SYSTEMS-4E-5 ADJUSTMENTS Refer to "Precautions", in this section, BE FORE proceeding. PRELIMINARY FLOAT ADJUSTMENT IMPORTANT: The preliminary float adjustment will provide a sufficient setting for starting the engine. Final float adjustments MUST be made with engine running. 1. Invert float bowl as shown in Figure 1. 2. Loosen locking screw and turn float adjustment nut to adjust float. (Figure 2) 3. Proper float adjustment is achieved when parting line on float is parallel with fuel bowl. Parting line must be parallel all the wav around float. 18588 a - Float b - Float Parting Line c - Fuel Bowl (Inverted) d - Parallel All The Way Around Float Figure 1. Preliminary Float Setting a - Locking Screw b - Adjustment Nut Figure 2. Adjusting Float Level 4. Repeat this procedure for both floats. 4E-6 - FUEL SYSTEMS FINAL FLOAT ADJUSTMENT 1. With carburetor mounted on engine, start engine and leave run for several minutes. 2. While engine is running remove sight plug on primary fuel bow l. (Figure 3) 3. Loosen locking screw and turn adjustment nut slowly until fuel can be seen even with the bottom of the sight plug hole. a - Locking Screw b - Adjustment Nut c - Sight Plug Hole d - Raises Fuel Level e - Lowers Fuel Level Figure 3. Final Float Adjustment 4. Tighten locking screw securelv being careful not to let adjustment nut turn. (Figure 3) 5. Reinstall sight plug and gasket. 6. Repeat this procedure for secondary side of carburetor. ACCELERATOR PUMP 1. With engine shut off. move throttle arm to W.O.T. position. 2. While holding throttle arm in W.O.T. position push down on primarv accelerator pump lever. (Figure 4) 3. With a feeler gauge check for clearance between adjustment screw and accelerator pump lever. Adjust screw and nut to specifications. 4. Repeat procedure for secondarv accelerator pump. (Figure 5) 90-95693 485 a - Pump Lever - Push Down a - Choke Housing Mark b - Feeler Gauge o - Choke Cover Mark c - Adjustment Screw and Nut c - Richer Adjustment Figure 4. Primary Accelerator Pump Adjustment d - Leaner Adjustment 3 - Cover Retaining Screws (One Not Shown) Figure 6. Choke Adjustment 2. If choke adjustment is necessary (Figure 6): a. Loosen 3 choke cover retaining screws and adjust as shown. b. Tighten 3 choke cover retaining screws securely. PRELIMINARY IDLE SPEED and MIXTURE IMPORTANT: The following adjustments will provide a sufficient setting to start engine. Final adjustments MUST BE made with engine running. 1. Turn idlespeed screw in until it just contacts idlecam. then turn screw in one additonal turn. (Figure 7) a - Pump Lever - Push Down b - Feeler Gauge c - Adjustment Screw and Nut Figure 5. Secondary Accelerator Pump Adjustment CHOKE ADJUSTMENT 1. Normal choke setting is such that scribed mar.< on choke cover is in line with center mark on choke housing. a - Idle Speed Screw b - Idle Cam Figure 7. Idle Speed Screw 90-95693 485 F JEL SYSTEMS - 4E-7 IMPORTANT: DO NOT turn idle mixture needles tightly against seat (in the following step), as damage to seat and/or needle may result. 2. Turn idle mixture needles in until they LIGHTLY SEAT: then back out 2 turns. (Figure 8) a - 2 Idle Mixture Screws - Only One Shown b - Primary Fuel Bowl Figure 8. Idle Mixture Screws FINAL IDLE SPEED and MIXTURE IMPORTANT: Boat MUST BE in the water and engine at normal operating temperature to accurately check and adjust idle speed and mixture. Carburetor should be set so that engine idles smoothly within range given under "Specifications", following, with boat in the water, engine at normal operating temperature and drive unit in forward gear. To adjust idle speed and mixture, procced as follows: IMPORTANT: DO NOT attempt to compensate for other engine problems (incorrect ignition timing, faulty ignition components, low compression, vacuum leaks, etc.) with carburetor adjustments. This will only cover the problem, which must be corrected if engine is to achieve maximum fuel economy and performance. 1. Connect a shop tachometer to engine. IMPORTANT: DO NOT turn idle mixture needle (Figure 9) tightly into seat (in next step), as damage to needle and/or seat may result. 2. If a new or rebuilt carburetor has been installed, turn idle mixture needles (Figure 9) in (clockwise) unit] it LIGHTLY contacts seat; then, back out needle 2 turns. This will provide a sufficient setting to allow starting engine. 3. Start engine and run at 1500 RPM until engine reaches normal operating temperature. DO NOT leave the helm unoccupied while performing idle speed and mixture adjustments, following. BE CAREFUL NOT TO ACCIDENTALLY ACCELERATE ENGINE WHILE PERFORMING ADJUSTMENTS. a - 2 Idle Mixture Screws - Only One Shown b - Primary Fuel Bowl Figure 9. Idle Mixture Adjustment 5A-8 - EXHAUST SYSTEM 90-95693 485 4. With boat in open water, place remote control in forward gear, idle position. 5. Disconnect throttle cable brass barrel from anchor stud. 6. Adjust idle speed adjustment screw (Figure 10) to obtain specified RPM. 7. With engine running at specified RPM. adjust idle mixture needle (Figure 9). as follows: a. Turn idle mixture needle inward (clockwise) until the engine speed begins to drop due to lean mixture. b. Turn idle mixture screw outward (counterclockwise) until the speed begins to drop due to a rich mixture. c. Turn screw inward to a point between these two extremes to obtain maximum engine smoothness and RPM. d. Repeat procedure with other needle. e. Readjust idle speed adjusting screw, if necessary, to obtain specified RPM. IMPORTANT: Refer to "Section 2, Part H" forthrottle cable installation and adjustment. a - Idle Speed Screw b - Idle Cam Figure 10. Idle Speed Adjustment REPAIR Throttle Body (Figure 1) Refer to "Precautions", in this section, BE FORE proceeding. 1. Vacuum tube is removed and a V»" \PT pipe plug is installed. MODIFICATIONS Primary Metering Body (Figure 2) IMPORTANT: There has been several modifications made to the Holley carburetor used on the 1. The idle feed holes are drilled to .040". 440/460 Cyclone. The carburetor will have "MOD" 2. A Vs" \PT pipe plug is installed in the vacuum hole. etched into casting at location shown in "Identifica 3. .084" jets are installed in both the primary and secondary tion "photo. metering blocks. 18594 a - Idle Feed Holes b - Plug Installed in This Hole Figure 2. 440/460 Cyclone Only 18601 a - Vacuum Tube is Removed Figure 1. 440/460 Cyclone Only 90-95693 485 FUEL SYSTEMS - 4E-9 Carburetor Body (Figure 3) 1. The original bowl vents are removed, the holes are drilled to .316" and new "J" tube vents are installed. 18609 a - New "J" Tube Bowl Vents Figure 3. 440/460 Cyclone and 475 Turbo REMOVAL IMPORTANT: Carburetor malfunctions are, in many cases, caused by the presence of dirt, water or other foreign matter in carburetor. To aid in diagnosis, carefully remove carburetor from engine without draining fuel from bowl. Contents of fuel bowl may, then, be inspected for contamination as carburetor is disassembled. 1. Remove crankcase ventilation hoses from flame arrestor: then, remove flame arrestor. IMPORTANT: Place a clean cloth in bores of carburetor to prevent dirt and foreign material from falling into bores. 2. Turn fuel supply off at fuel tank. 3. Disconnect throttle cable from carburetor. 4. Remove fuel lines. Refer to Figure 1 under "Fuel Inlet Filter". 5. Remove fuel pump sight tube. 6. Disconnect electric choke. 7. Remove carburetor attaching nuts and washers and remove carburetor. 8. Remove and discard gaskets. IMPORTANT: Place a clean cloth over intake manifold opening to prevent dirt or foreign material from entering manifold. INSTALLATION 1. Thoroughly clean gasket surfaces. L se care to prevent gasket material from entering intake manifold. 2. Place new carburetor base gasket on intake manifold. Install carburetor and secure with nuts and washers. Torque to specifications. 3. Connect fuel lines to fuel inlet nuts and torque to specifications. 4. Connect fuel pump sight tube. 5. Connect electric choke wires to choke cover. 6. Move throttle lever back-and-forth and check for binding in throttle linkage. 7. Install throttle cable, as explained, in "Section 2. Part H". 8. Install flame arrestor and crankcase ventilation hoses. 9. Reconnect battery cables to battery. 10. Start engine and check for gasoline leaks. If leaks exist, STOP ENGINE IMMEDIATELY and recheck connections. 11. Adjust idle speed and idle mixture, as outlined under "Adjustments", preceding. DISASSEMBLY The following is a step-by-step procedure for completely overhauling carburetor removed from engine. In many cases, however, complete overhaul is not necessary and, in these cases, only the steps required to repair the carburetor malfunction should be performed. Read the instructions carefully to prevent doing any unnecessry steps. IMPORTANT: Before performing any service on carburetor, it is essential that carburetor be placed in a holding fixture to prevent possible damage to throttle valves. Choke Housing 1. Remove choke cover. (Figure 1) a - Choke Cover Retaining Screws b - Choke Cover c - Choke Cover Retainer d - Gasket Figure 1. Removing Choke Cover 5A-10 - EXHAUST SYSTEM 90-95693 485 2. Remove choke rod retaining clip. (Figure 2) 1. Remove fuel inlet filter nuts, gaskets, filters, and springs as outlined. 2. Remove idle mixture screws and gaskets. (Figure 4) 18603 a - Choke Housing b - Housing Retaining Screws c - Ground Wire d - Vacuum Hose e - Choke Rod Retaining Clip f - Choke Rod Figure 2. Removing Choke Rod Retaining Clip a - Gaskets b - Idle Mixture Screws c - Idle Mixture Chamber (Only 1 Shown) Figure 4. Removing Idle Mixture Screws 3. Remove primary and secondary fuel bowls. (Figure 5) 3. Remove choke housing. (Figure 3) 18583 a - Choke Housing b - Retaining Screws c - Ground Wire d - Vacuum Hose Figure 3. Removing Choke Housing Fuel Bowls and Metering Bodies IMPORTANT: As the rest of the carburetor is disassembled all of the parts from the primary side (of the carburetor) should be kept seperated from secondary side parts. This will assure all of the parts are installed properly upon reassembly. a - Fuel Bowl Retaining Screws and Gaskets (Gaskets Not Shown) Used on 475 Turbo b - Primary Fuel Bowl c - Secondary Fuel Bowl d - Screws Used on 440/460 Cyclone e - Gasket Figure 5. Removing Fuel Bowls IMPORTANT: Carburetors used on the 440/460 Cyclone engines will have long thru-bolts holding the fuel bowls onto the carburetor. Early carburetors used on the 475 Turbo engine will be as shown in Figure 5. Later models may have long thru-bolts also. 90-95693 485 FUEL SYSTEMS - 4E-11 4. Remove needle seal and float assembly from fuel bowls. 4. Remove accelerator pump assembly, sight plug and gasket. (Figures 6 and 7) (Figure 8) a - Locking Screw d - Pump Return Spring b - Adjustment Nut e - Pump Diaphragm c - Float Retaining Screws f - Pump Housing d - Float g - Pump Housing Retaining Screws h - Pump Check Valve - NOT REMOVA3LE Figure 6. Removing Needle Seat and Float Figure 8. Accelerator Pump Removed IMPORTANT: Needle seat and needle are factory assembled and must be serviced as an assembly. 5. Accelerator pump check balls are not removable. Check for clearance between ball and retainer. Check ball Ml ST be a. Loosen locking screw. b. Turn adjustment nut counterclockwise to remove needle seat assembly. c. Remove float retaining screws and remove float. 18597 a - Fuel Bowl b - Gasket c-Sight Plug 18589 a - Retainer b - Check Ball c - Refer to "Specifications" Figure 9. Accelerator Pump Check Ball 18596 free to move as specified. (Figure 9) a - Fuel Bowl b - Float c - Float Retaining Screws d Locking Screw e - Gasket f - Adjustment Nut g - Gasket h - Needle and Seat Assembly i - "O" Ring 6. Remove attaching springs, studs, gaskets, primary, and secondary metering bodies from carburetor. (Figures 10 and 11) IMPORTANT: Some model carburetors will have Figure 7. Needle and Removed Seat and Float Assembly long thru-bolts instead of the attaching springs and studs. 4E-12FUEL SYSTEMS 90-95693 485 8. Remove main fuel jets from primarv arid secondary metering bodies. (Figure 13) 18586 a - Attaching Springs (475 Turbo Only) b - Gaskets c - Primary Metering Body d - Secondary Metering Body e - Gasket f - Studs (475 Turbo Only) g - Thru-Bolt Used on 440/460 Cyclone Engines, h - Gasket Figure 10. Removing Metering Bodies a - Main Fuel Jets Figure 13. Main Fuel Jets Removed 9. Remove float bowls vent tubes. Pry down on top of vent tube with a small screwdriver and pull out. \ ent tubes are held in place with small locating pin. ^Figure 14) IMPORTANT: Locating pins should NOT be removed from metering bodies. 18595 a - Primary Metering Body b - Power Valve c - Secondary Metering Body (No Power Valve) d - Float Bowl Vent Tubes Figure 11. Metering Body Identification 7. Remove power valve from primary metering bod v. Power valve cannot be serviced separately, if defective it must be replaced. (Figure 12) a - Small Screwdriver b - Float Bowl Vent Tube Figure 14. Removing Float Bowl Vent Tubes a - Primary Metering Body b - Gasket c - Power Valve Figure 12. Power Valve Removed 18590 90-95693 485 FLEL SYSTEMS - 4E-13 Carburetor Body Throttle Body 1. Remove 2 screws which hold accelerator pump discharge 1. Remove 6 screws which hold throttle body to carburetor needles in place. (Figure 15) body. (Figure IT) a - Screws Figure 15. Accelerator Pump Discharge Needle Retaining Screws. 2. Remove pump discharge needles and components. (Figure 16) a - Remove 6 Screws Figure 17. Removing Throttle Body 2. Remove carburetor body and gasket from throttle body. (Figure 18) 18598 a - Screws b - Gaskets c - Bushings d - Gaskets e - Needles Figure 16. Pump Discharge Needle Removed. a - Carburetor Body IMPORTANT: Choke valves should NOT BE RE- b - Gasket MOVED from carburetor body, if damaged, car-c - Throttle Body buretor body should be replaced. Figure 18. Throttle Body Removed From Carburetor Body IMPORTANT: Further disassembly of the throttle body is normally not required. Throttle valves should NOT BE REMOVED. If throttle valves are damaged, throttle body should be replaced. 5A-14 - EXHAUST SYSTEM 90-95693 485 CLEANING and INSPECTION Carbon, varnish, sum. dirt, and water contaminants in the carburetor or on exterior moving parts of the carburetor often are responsible for carburet ion malfunctions. Therefore, care- full v observe the following cleaning and inspection procedure, to obtain effective carburetor repair. IMPORTANT: DO NOT use a wire or drill to clean jets, passages, or tubes in carburetor, as this may enlarge orifices and seriously affect carburetor calibration. IMPORTANT: DO NOT clean float bowl gasket surfaces with a gasket scraper or knife, as sealing bead will be damaged and componenet replacement will be necessary. IMPORTANT: All gaskets, "O" rings, and seals should be replaced during carburetor repair. 1. Thoroughly clean all metal parts in a commercial carburetor cleaner, until all deposits have been removed. Follow manufacturer's instructions of cleaner being used for proper cleaning and rinsing procedure. Dry parts with compressed air. 2. I sing compressed air. blow out all passages in carburetor to remove anv foreign material. 3. Wipe-off all pa-ts that cannot be cleaned in carburetor cleaner with a clean, drv cloth. 4. Carefully inspect all carburetor parts for wear and damage; pay particular attention to the following: a. Float Needle and Seat: if float needle or seat is worn or damaged, replace w ith a new needle and seat assembly. IMPORTANT: Float needle and seat are factory assembled. Needle and seat cannot be serviced separately. b. Float Assembly and Hinge Pin: Inspect float pontoon for deterioration and porositv. Check pontoon density (to see if it is saturated with fuel). by comparing weight of float with specifications. (Figure 1) If pontoon weight is high, float assembly MUST BE replaced. Shake float. 1 i float contains fuel inside, float is leaking atid must be replaced. Check hinge pin and holes for wear. c. Fuel and Air Passages: Passages Ml ST RE perfectly clean for proper carburetor operation. a - Scale b - Float Figure 1. Checking Float Weight d. Accelerator Pump Diaphragm and Return Spring: Inspect pump diaphragm, check ball, discharge needles, and return spring. e. Power Piston Spring: Check power piston spring for weakness or distortion. f. Idle Mixture Needles: Inspect idle mixture needles. If damaged, needles MUST BE replaced. g. Levers and Linkages: Check levers, links and rods for wear. h. Throttle Valve and Shaft: Check throttle shaft for excessive looseness in throttle bodv. Check throttle valve and shaft for binding thru entire operating range, making sure valve opens and closes completely. Throttle body assembly MUST BE replaced if throttle valve and shaft arc worn or damaged. i. Choke \ alveand Shaft and Lever Assembly: Check shaft and lever assembly for excessive looseness in air horn assembly. Check choke valve and shaft and lever assembly for binding thru entire operating range, making sure valve opens and closes completely. Carburetor body assembly MUST BE replaced if choke valve and shaft and lever assembly are worn or damaged. j. Inspect casting for visible damage. Inspect gasket surfaces. 90-95693 485 FUEL SYSTEMS - 4E-15 REASSEMBLY Carburetor Body Throttle Body 1. Install pump discharge needles into carburetor bodv in order shown in Figure 3. Tighten screws securelv. (Figure 4) 1. Assemble throttle body to carburetor body using a new gasket, being careful to line up gaskel and carburetor body with locating pins in throttle body. (Figure 1) a - Screws b - Gaskets c - Bushings d - Gaskets e - Needles Figure 3. Installing Pump Discharge Needles 18587 a - Carburetor Body b - New Gasket c - Throttle Body d - Locating Pins Figure 1. Installing Throttle Body 2. Install throttle bod\ attaching screws and tighten evenly and securely. (Figure 2) a - Pump Discharge Needle Retaining Screws Figure 4. Retaining Screws Installed a - 6 Attaching Screws Figure 2. Installing Attaching Screws 18601 4E-16- FUEL SYSTEMS 90-95693 485 Fuel Bowls and Metering Bodies 3. Instal. power valve and new gasket in primary metering body. 1. Install fuel bowl vent tubes into metering bodies, vent tube must be pushed in far enough to lock into locating pin. (Figure 5) 18593 a - Vent Tube b - Locating Pin Figure 5. Installing Vent Tubes 2. Install primary and secondary main fuel jets. (Figure 6) a - Primary Metering Body b - Gasket c - Power Valve Figure 7. Installing Power Valve 4. Assemble metering bodies to carburetor body in order shown in Figure 8. IMPORTANT: On 440/460 Cyclone carburetors this operation cannot be performed until fuel bowls are assembled because the carburetor has through bolts in place of the springs. 18591 a - Main Fuel Jets Figure 6. Installing Main Fuel Jets a - Springs (475 Turbo Only) b - Gasket c - Primary Metering Body d - Secondary Metering Body e - Gasket f - Studs (475 Turbo Only) g - Thru-Bolts (440/460 Cyclone) h - Gasket Figure 8. Installing Metering Bodies 90-95693 485 EXHAUST SYSTEM - 5A-17 8. Assemble float, spring, hinge, and hinge pin as shown in 5. Install accelerator pump assembly as shown in Figure 9. Figure 11. 6. Install sight plug and gasket. Tighten screws securely. 18592 a - Float c - Hinge b - Hinge Pin d-Spring Figure 11. Assembling Float 9. Install float, and float retaining screws. (Figure 12) Tighten screws securely. Install needle seat assembly. Adjust float to specifications. See "Adjustments" in this 18597 section. a - Fuel Bowl e - Diaphragm b - Gasket f - Pump Housing c - Sight Plug g - Screws d - Spring h - Check Ball Figure 9. Installing Accelerator Pump 7. Assemble needle sear as shown in Figure 10. 18589 a - Locking Screw b - Adjustment Nut c - Float Retaining Screws d - Float Figure 12. Installing Float and Needle Seat 10. Install fuel bowls as shown in Figure 13. Tighten screws securelv. a - Locking Screw b - Gasket 18585 c - Adjustment Nut a - Screw and Gaskets (Gaskets Not Shown) d - Gasket b - Primary Fuel Bowl e - Needle Seat Assembly c - Secondary Fuel Bowl f - "O" Ring 18596 d - Thru-Bolts (440/460 Cyclone) e - Gasket Figure 10. Needle Seat Assembly Figure 13. Installing Fuel Bowls 4E-18- FUEL SYSTEMS 90-95693 485 11. Install fuel inlet filter components, fuel inlet gasket, and nut as shown in Figure 14. Tighten nut securely. 17585 a - Spring c - Gasket b - Filter (Open End Towards Nut) d - Fuel Inlet Nut Figure 14. Installing Filter and Inlet Nut 12. Install idle mixture screws and gaskets. Lightlv seat needle, then back out 2 turns. (Figure 15) IMPORTANT: Do not tighten idle mixture needles against seats or damage to needle and/or seat may result. \ o ^ o 18582 a - Gaskets c - Idle Mixture Hole (Only One Shown) b - Needles Figure 15. Installing Idle Mixture Screws Choke Housing 1. Install choke housing as shown in Figures 16 and 17. Tighten screws securley. 2. Install choke rod retaining clip. 1860 3 a - Choke Housing d - Vacuum Hose b - Screws e - Choke Rod Retaining Clip c-Ground Wire f-Choke Rod Figure 17. Retaining Clip installed 3. Install choke cover as shown in Figure 18. Adjust choke to "Specifications". Tighten screws securely. Be sure to hook choke heat element into choke lever. a - Choke Cover Retaining Screws b - Choke Cover c - Retainer d - Gasket 18584 Figure 18. Installing Choke Cover a - Choke Housing c-Ground Wire b - Screws d - Vacuum Hose Figure 16. Installing Choke Housing 90-95693 485 EXHAUST SYSTEM - 5A-19 SECTION 5 - EXHAUST SYSTEM PART A - EXHAUST MANIFOLDS/ELBOWS INDEX Page Torque Specifications 5A-1 Sealants 5A-2 Cleaning and Inspection 5A-2 MCM 120/140/165 5A-3 MCM/MIE 470 5A-4 MCM 470R/485/488R 5A-7 MCM 898/228/260 5A-8 MCM 898R/228R/260R 5A-9 MCM 330/370/400/400 Cyclone 5A-11 MCM 330 (B-W) 5A-11 MIE 230/260/340 5A-11 MIE 228/255/330 5A-12 TORQUE SPECIFICATIONS MCM 120/140/165 Fastener Location Lbs. Ft. (N.m) Lbs. In. (N.m) Battery Cables Securely Carburetor 20 (27) Hose Clamps Securely End Cap 96 (11) Exhaust Elbow 25 (34) Exhaust Manifold (Note 1) 23 (33) Intake Manifold Cover 15 (20) NOTE 1: Retorque after engine has been brought up to operating temperature. MCM/MI E 470 Fastener Location Lbs. Ft. (N.m) Lbs. In. (N.m) Battery Cables Securely Hose Clamps Securely End Cap 96 (11) Exhaust Elbow 25 (34) Exhaust Manifold 25 (34) Reservoir 20 (27) Thermostat/Distribution Housing 20 (27) MC M 470R/485/488R Fastener Location Lbs. Ft. (N.m) Lbs. In. (N.m) Battery Cables Securely Hose Clamps Securely Exhaust Elbow/Reservoir 30 (41) Exhaust Manifold 25 (34) Thermostat Housing 20 (27) 90-95693 485 EXHAUST SYSTEM - 5A-1 MC M 898/228/260/330/370/400/400 Cyclone/47 5 Turb o MIE 228/230/255/260/330/340 Fastener Location Lbs. Ft. (N.m) Lbs. In. (N.m) Battery Cables Securely Hose Clamp s Securely Distribution Block 25 (34) End Ca p 96 (11) Exhaust Elbow 25 (34) Exhaust Manifold (Note 1) 25 (34) NOTE 1: MCM 370/400/400 Cyclone/475 Turbo 35 lbs. ft. (48 N.m) on bolts, 25 lbs. ft. (34 N.m) on nuts. SEALANTS SEALANT S 92-32609-1 Quicksilver Loctite 92-34227—1 Quicksilver Perfect Seal CLEANING and 1. Clean gasket material from all surfaces and wash parts in solvent. 2. Inspect all parts carefully. Machined surfaces must be clean and free of all marks and deep scratches, or water and exhaust leaks may result. 3. Check water passages for foreign material. Passages must be clean for efficient cooling. 4. If more thorough inspection is desired, pipe plugs mav be removed from exhaust manifold and exhaust elbow. IMPORTANT: If plugs are removed, coat threads with Perfect Seal before reinstalling. INSPECTION 5. Check for cracks. 6. To test manifold body for leaks, block off plates, plugs, or short hoses with plugged ends must be used. One block off plate must have a threaded hole for attaching compressed air hose. Use new gaskets when installing block off plate(s). Apply 40 PSI (276 kPa) of air pressure and submerge manifold in water. Air bubbles will indicate a leak. MCM 470R/485/488R: Using new gaskets, install elbow/reservoir assembly to manifold bodv. Using hoses, plugs and clamps, seal all openings that coolant would flow- thru (seawater inlet and outlet do not have to be plugged). Pressure check the assembly, using automotive radiator tester. Follow tool manufacturer s instructions. 5A-2 - EXHAUST SYSTEM 90-95693 485 MCM 120/140/165 REMOVAL 1. Disconnect battery cables from battery. 2. Drain water from cylinder block, exhaust manifold and exhaust elbow. 3. Disconnect throttle cable at carburetor. MCM 120R/140R : Remove both shift cables from shift plate assmebly. 4. Disconnect exhaust hose and cooling hoses. 5. Disconnect fuel line at carburetor. 6. Disconnect crankcase ventilation hose at rocker arm cover. 7. Remove wiring harness clamps and slave solenoid from manifold. MCM 120R/ 14-OR: Disconnect engine harness shift cutout switch wires and wires going to electric choke. 8. Remove exhaust manifold fasteners: remove manifold assemblv and discard gaskets. 9. Remove exhaust elbow. MCM 120R/140R: Remove exhaust adaptor. 10. Refer to "Cleaning and Inspection . IMPORTANT: MCM 120: If manifold to cylinder head studs have broken, install all new studs with Loctite "A" after checking head and manifold surfaces for warpage. Also use all new manifold attaching nuts. INSTALLATION If exhaust manifold body requires replacement, transfer all parts (from old manifold) to new manifold bodv. 1. Position new gasket on head and install manifold in position. making sure gasket is in place. 2. Tighten fastene-s evenlv and torque to specifications, starting in center and working out toward ends. IMPORTANT: After engine has been brought up to operating temperature, allow engine to cool. Re- torque manifold fasteners. 3. Install carburetor (if removed) and connect crankcase ventilation hose at rocker arm cover. 4. Install wiring harness clamps and slave solenoid to manifold. 5. Install exhaust elbow using new gasket. (Figure 1 or 2) Torque to specifications. MCM 120R/ 140/ 110R/ 165: Gaskets must be installed as shown in Figure 1. IMPORTANT: If engine is equipped with a 3" or 6" riser, refer to "Section 5, Part B". Figure 1. Gasket Installation MCM 165 with Reversed W ater Flow: IMPORTANT: Be certain that the wide part of gas- ket/plate is positioned toward front of engine. a. Coat both sides of gaskets with Perfect Seal. b. Install kit as shown in Figure 2. Be sure to perform the following: • Torque exhaust elbow nuts to specifications. • Tighten end cap screws securely. • Tighten all hose clamps securely. 90-95693 485 EXHAUST SYSTEM - 5A-3 a - Wide Part Figure 2. MCM 165 with Reversed Water Flow 6. Connect throttle cable to carburetor. Adjust as outlined in "Removal. Installation and Alignment " section. MCM 120R/140R: Connect both shift cables as shown in Figure 3. Also reconnect engine harness shift cutout switch wires to terminal block. IMPORTANT: Adjust shift cables as outlined in "Stern Drive Service Manual". a - Remote Control Shift Cable Attaching Points b - Drive Unit Shift Cable Attaching Po nts C - Exhaust Manifold Figure 3. MCM 120R/140R 7. Connect fuel line and choke tube or electric choke wires. 8. Reinstall exhaust and cooling hoses. 9. Reconnect batters cables to batterv. Tighten securely. 10. Start engine, check for exhaust, water and fuel leaks and adjust carburetor idle speed and mixture. MCM/MIE 470 NOTICE Refer to Figure 1 for parts breakdown. REMOVAL 1. Disconnect battery cables from battery. 2. Drain engine coolan - and seawater. 3. Disconnect wire from temperature sending unit. 4. Disconnect all water and exhaust hoses from manifold assembly. MOTE: You may have, to drain engine oil and remove dipstick tube to remove manifold. 5. Remove wiring harness clamps and starter solenoid from manifold. 6. Remove exhaust manifold fasteners. Remove manifold assembly and discard gasket. DISASSEMBLY 1. Remove coolant reservoir from thermostat/distribution housing and remove thermostat. 2. Remove thermostat/distribution housing from manifold body. 3. Remove temperature sender and bras- plug from thermostat/ distribution housing. 4. Remove exhaust elbow from manifold body. 5. Remove end cap from aft end of manifold bod\. 6. Refer to "Cleaning and Inspection". 5A-4 - EXHAUST SYSTEM 90-95693 485 REASSEMBLY 3. Apply Perfect Seal to threads and install temperature sender and brass plug. 1. Install new gasket and end cap on aft end of manifold 4. Install new gasket, thermostat/distribution housing and body (with hose connector facing toward engine sides of attaching bolts, using copper washers. Torque to specifica manifold). Torque to specifications. tions. 2. Place new gasket, plate, second gasket and exhaust elbow 5. Place thermostat (umbrella down) into its cavity in housonto manifold body, as shown in Figure 1 for MCM models ing. Install new gasket, coolant reservoir and attaching and Figure 2 for MIE models. Install lockwasher and nuts. bolts with flat washers and lockwashers. Torque to specifi- Torque to specifications. cations. IMPORTANT: If engine is equipped with a 3" or 6" riser, refer to "Section 5, Part B". a - Bolts (4) s - Reservoir to Thermostat/Distribution Housing b - Copper Washers (4) Long Bolts (2) c - Thermostat-Distribution Housing t - Pressure Cap d-Brass Plug u - Pressure Cap Gasket e - Temperature Sender v - Overflow Fitting f - Gasket w - Bleed Hose Fitting g - Manifold Body x - Lockwashers (8) h - Manifold Body to Cylinder Head Gasket y - Bolts (6) i - Drain Plug z . Nuts (2) j-Gasket aa - Exhaust Elbow k-End Cap bb - Lockwashers (4) I - Bolts (4i cc - Nuts (4) m - Thermostat dd - Hose Connector Elbow n - Gasket ee - Gasket o - Coolant Reservoir ff - Plate p - Flat Washers (4) gg . Gasket q - Reservoir to Thermostat/Distribution Housing hh - Bleed Hose Fitting Short Bolts (2) jj - Drain Plug r - Lockwashers (4) Figure 1. MCM/MIE 470 90-95693 485 EXHAUST SYSTEM - 5A-5 a - 77936A1 Aluminum Casting b- 77936A1 Cast Iron Casting Figure 2. MIE 470 Engines 5A-6 - EXHAUST SYSTEM 90-95693 485 2. Connect all water and exhaust hoses to manifold assembly. INSTALLATION Tighten hose clamps securely. 3. Connect engine harness wire to temperature sender. 1. I sing a new gasket, position manifold assembly onto 4. Install wiring harness clamps and starter solenoid. cylinder head and install lockwashers, nuts and bolts. 5. P"ill closed cooling system to proper coolant level. Torque to specifications. 6. Pressure check the cooling system, using automotive radiator tester. Follow tool manufacturer's instructions. \OTE: If removed, install dipstick tube to oil pan and to 7. Reconnect battery cables to battery. Tighten securely. support clamp located on exhaust manifold fastener boll. Fill 8. Start engine and check for leaks. engine to proper oil level. MCM 470R/485/488R REMOVAL 1. Disconnect battery cables from battery. 2. Drain engine coolant and seawater. 3. Disconncct wire from temperature sending unit. 4. Disconnect all hoses and exhaust bellows from manifold assembly. MOTE: You may have to drain engine oil and remove dipstick tube to remove manifold. 5. Remove wiring harness clamps from manifold. 6. MCM 470R/488R: Remove both shift cables from shift plate assembly. 7. MCM 470R/488R: Disconnect engine harness shift cutout switch wires. 8. Remove exhaust manifold fasteners. Remove manifold assembly and discard gasket. DISASSEMBLY NOTICE To test manifold and reservoir for leaks, refer to "Cleaning and Inspection" before disassembly. 1. Remove exhaust elbow/reservoir assembly. 2. Remove thermostat housing and thermostat. 3. Remove temperature sender and brass plug. 4. Refer to "Cleaning and Inspection". REASSEMBLY 1. If manifold body requires replacement, transfer parts from old bodv. 2. If exhaust elbow/reservoir requires replacement, transfer parts from old assembly. 3. L sing new gaskets, install exhaust elbow/reservoir assembly to manifold. Torque to specifications. IMPORTANT: Gaskets and plate must be installed as shown in Figure 1 or leak will occur. a - Gasket b - Stainless Steel Plate (Slot Forward) 4. Using Perfect Seal on threads, install temperature sender c - 27-97542 Separator Gasket (Slot Forward) and brass plug. 5. Using new gasket, install thermostat and thermostat hous- Figure 1. Plate or Gasket Installation ing. Torque to specifications. 90-95693 485 EXHAUST SYSTEM - 5A-7 INSTALLATION 1. Using a new gasket, position manifold assemblv onto cylinder head and install lockwashers, nuts and bolts. Torque to specifications. XOTE: If removed, install dipstick tube to oil pan and to support clamp located on exhaust manifold fastener bolt. Fill engine to proper oil level. 2. Connect all hoses ar.d exhaust bellows to manifold assembly. Tighten clamps securely. 3. Connect engine harness wire to temperature sender. 4. Install wiring harness clamps. 5. MCM 470R/488R: Reconnect engine harness shift cutout switch wires to terminal block. 6. MCM 470R/488R: Connect both shift cables a? shown in I igure 2. IMPORTANT: Adjust shift cables as outlined in "Stern Drive Service Manual". 7. Fill closed cooling system to proper coolant level. 8. Pressure check the cooling system, using automotive radiator tester. Follow tool manufacturer's instructions. 9. Start engine and check for leaks. a - Remote Control Shift Cable Attaching Points b - Drive Unit Shift Cable Attaching Points c - Exhaust Manifold Figure 2. MCM 470R/488R MCM 898/228/260 REMOVAL 1. Disconnect battery cables from batter). 2. Drain water from manifold and exhaust elbow. 3. Disconnect exhaust bellows and cooling hoses. 4. Starboard Manifold: a. Disconnect fuel lines from water separating fuel filter and remove fuel filter assembly. b. Remove slave solenoid and bracket. Port Manifold: a. Remove alternator and mounting bracket. 5. Remove exhaust manifold fasteners; removeassembly and discard gaskets. 6. Remove exhaust elbow. 7. Remove end caps. 8. Refer to "Cleaning and Inspection". INSTALLATION manifold 1. Install new gaskets and end caps on ends of manifold body. Torque to specifications. 2. Place new gasket, plate, second gasket and exhaust elbow onto manifold body, as shown in Figure 1. Install lock- washer and nuts. Torque to specifications. IMPORTANT: If engine is equipped with a 3" or 6" riser, refer to "Section 5, Part B". If engine is equipped with a closed cooling system, refer to Figure 2. 3. Using new gasket, install manifold. Torque to specifications. 4. Starboard Manifold: a. Install water separating fuel filter. Connect fuel lines and lighten securely. b. Install slaw solenoid and bracket. Tighten fasteners securely. Port Manifold: a. Install alternator bracket. Tighten bolts securely. b. Install alternator and adjust belt tension. Tighten all fasteners securely. 14383A a - Exhaust Manifold b - Exhaust Elbow c - Wide Part of Gaskets/Plate (Vent Hole Forward) and Manifold/Elbow d - Narrow Part of Gaskets/Plate and Man fold/Elbow Figure 1. Without Closed Cooling 5A-8 - EXHAUST SYSTEM 90-95693 485 5. Reconnect exhaust bellows and water hoses. Tighten clamps securelv. 6. Reconnect battery cables to battery. Tighten securely. 7. Start engine and check for fuel, exhaust and water leaks. a - Distribution Block (Water Passages Toward Manifold) b - Wide Part of Gasket Forward c - Hose Fitting Forward Figure 2. With Closed Cooling MCM 898R/228R/260R 10523 REMOVAL 1. Disconnect battery cables from batterv. 2. Drain water from manifold and exhaust elbow. 3. Disconnect exhaust bellows and cooling hoses. 4. Starboard Manifold: a. Disconnect both shift cables. b. Disconnect instrument harness plug from engine harness. Remove shift plate assembly from exhaust elbow . c. Disconnect fuel lines and remove filter assemblv. d. Remove circuit breaker/slave solenoid and bracket. Port Manifold: a. Remove ignition amplifier from exhaust elbow. 5. Remove exhaust manifold fasteners: remove manifold assemblv and discard gaskets. 6. Remove exhaust elbow. 7. Refer to "Cleaning and Inspection". INSTALLATION 1. Using new gasket, install exhaust manifold to cylinder head. Torque to specifications. 2. Install exhaust elbow as shown in Figure 1. Torque to specifications. a - Stainless Steel Restrictor Plate b - Gaskets c - 27-41813 Restrictor Gasket Figure 1. Without Closed Cooling IMPORTANT: If engine is equipped with a 3" or 6" riser, refer to "Section 5, Part B". If engine is equipped with a closed cooling system, refer to Figure 2. 148-hr1 90-95693 485 EXHA JST SYSTEM - 5A-9 c. Install shift plate assembly. Plugin instrument harness plug and tighten clamp securely. d. Connect both shift cables as shown in F igure 3. IMPORTANT: Adjust shift cables as outlined in "Stern Drive Service Manual". Port Manifold: a. Install ignition amplifier to exhaust elbow. Tighten bolts securely. a - Remote Control Shift Cable Anchor Points a - Stainless Steel Separator Plate b - Drive Unit Shift Cable Anchor Points b - Gaskets Figure 3. Shift Cable Connections c - 27-41811 Separator Gasket Figure 2. With Closed Cooling 4. Reconnect exhaust bellows and cooling hoses. Tighten Starboard Manifold: clamps securely. a. Install circuit breaker/slave solenoid and bracket. 5. Reconnect battery cables to battery. Tighten securely. b. Install water separating fuel filter. Reconnect fuel 6. Start engine and check for fuel, exhausl and water leaks. lines. Tighten securely. -10- EXHAUST SYSTEM 90-95693 485 MCM 330/370/400/400 Cyclone NOTICE INSTALLATION MCM 475 Turbo models can follow the pro cedure as outlined for MCM 370/400, however, 1. Install new gaskets and end caps on ends of manifold bod v. the removal of the turbo is not covered in this Torque lo specifications. manual. MCM 440 Cyclone/460 Cyclone mod-2. MCM 330: Place new gasket, vented plate, second gasket els use a different type of exhaust system and and exhaust elbow on manifold bodv. Torque to specifi its repair is not covered in this manual. cations. MCM 370/400/400 Cyclone: Place new gasket and exhaust elbow on manifold body. Torque to specifications. REMOVAL IMPORTANT: If engine is equipped with a 3" or 6" riser, refer to "Section 5, Part B". 1. Disconnect battery cables from batterv. 2. Drain water from manifold and exhaust elbow. 3. Disconnect exhaust hoses and cooling hoses. 3. I sing new gasket, install manifold. Torque to specifica4. Starboard Manifold: tions. a. Disconnect fuel lines from water separating fuel filter 4. Starboard Manifold: and remove fuel filter assembly. a. Install water separating fuel filter. Connect fuel lines 5. Remove exhaust manifold fasteners: remove manifold and tighten securelv. assembly and discard gaskets. 5. Reconnect exhaust and water hoses, lighten clamps 6. Remove exhaust elbow. securelv. 7. Remove end caps. 6. Reconnect batten cables to batterv. Tighten securelv. 8. Refer to "Cleaning and Inspection". 7. Start engine and check for fuel, exhaust and water leaks. MCM 330 (B-W)/MIE 230/260/340 REMOVAL 1. Disconnect battery cables from batterv. 2. Drain water from manifold and exhaust elbow. 3. Disconnect exhaust and cooling hoses. 4. Starboard Manifold: a. Disconnect fuel lines from water separating fuel filter and remove filter assembly. b. Disconnect instrument harness plug from engine harness. c. Remove circuit breaker/slave solenoid and bracket. Port Manifold: a. Remove ignition amplifier from exhaust elbow. b. Remove remote oil filter and bracket. 5. Remove exhaust manifold fasteners: remove manifold assembly and discard gaskets. 6. Remove exhaust elbow. 7. Refer to "Cleaning and Inspection". INSTALLATION 1. I sing new gasket, install exhaust manifold to cylinder head. Torque to specifications. 2. Install exhaust elbow as shown in Figure 1. Torque to specifications. IMPORTANT: If engine is equipped with a 3" or 6" riser, refer to "Section 5, Part B". If engine is equipped with a closed cooling system, refer to Figure 2. a - Stainless Steel Restrictor Plate b - Gaskets c - 27-41813 Restrictor Gasket Figure 1. Without Closed Cooling 90-95693 485 EXHAUST SYSTEM - 5A-11 3. Starboard Manifold: 148-hr 2 a. Install circuit breaker/slave solenoid and bracket. b. Install water separating fuel filter. Reconnect fuel lines. Tighten securely. c. Plug in instrument harness plug and tighten clamp securely. Port Manifold: a. Install ignition amplifier to exhaust elbow. Tighten bolts securely. b. Install remote oil filter and bracket. Tighten fasteners securely. 4. Reconnect exhaust and cooling hoses. Tighten clamps securely. 5. Reconnect battery cables to battery. Tighten securely. 6. Start engine and check for fuel, exhaust and water leaks. a - Stainless Steel Separator Plate b - Gaskets c - 27-41811 Separator Gasket Figure 2. With Closed Cooling MIE 228/255/330 5. Remove exhaust manifold fasteners; remove manifold REMOVAL assembly and discard gaskets. 6. Remove exhaust elbow. 1. Disconnect battery cables from battery. 7. Remove end caps. 2. Drain water from manifold and exhaust elbow. 8. Refer to "Cleaning and Inspection". 3. Disconnect exhaust and cooling hoses. 4. Starboard Manifold: MIE 228/255 V-DRIVE WITH REVERSED EX- a. Disconnect fuel lines from water separating fuel filter HAUST MANIFOLDS: These V-Drive engines had the and remove fuel filter assembly. exhaust outlet (of the manifold) at the front (circulating b. Remove slave solenoid and bracket. pump) end of the engine. If the manifold (with the alter- Port Manifold: nator mounted to it) has to be replaced, refer to Figure 1 a. Remove alternator and mounting bracket. for drilling instructions to new manifold. 90-95693 485 5A-12 - EXHAUST SYSTEM a - 5/16" Drill - .680" Deep 3/8-16 UNC-2B Tap - .560" Deep Figure 1. MIE 228/255 V-Drive with Reversed Manifolds 90-95693 485 EXHAUST SYSTEM - 5A-13 INSTALLATION IMPORTANT: If engine is equipped with a 3" or 6" 1. Install new gaskets and end caps on ends of manifo.d body. Torque to specifications. 2. Place new gasket, plate (Figure 2 or 3), second gasket and exhaust elbow onto manifold as shown in Figure 4 or 5. Torque to specifications. riser, refer to "Section 5, Part B". IMPORTANT: Closed Cooled Engines: If engine has exhaust elbow mounted right on manifold body, plate (without Vs" vent hole) and gaskets are installed as shown in Figure 4. If engine has water distribution blocks, refer to Figure 6 or 7. a - 60207 Plate with 1/8" Vent Hole - MIE V-Drive Engine and MIE Engine (with In-Line Transmission) if Engine is Mounted Level b - 55730 Plate without Vent Hole - MIE Engine (with In-Line Transmission) Mounted at an Angle Figure 2. MIE 228/255 Plates 5A-14 - EXHAUST SYSTEM 90-95693 485 a - 73782 Plate wth 1/8" Vent Hole - MIE V-Drive Engine and MIE Engine (with In-Line Transmission) if Engine is Mounted Level b - 74829 Plate w thout Vent Hole - MIE Engine (with In-Line Transmission) Mounted at an Angle Figure 3. MIE 330 Plates 14383A 07019A a - Front of Manifold Body b - Gaskets - MIE 228/255: Wide Part Toward Front of Manifold. MIE 330: Either Way. c - Plate - MIE 228/255: Wide Part Toward Front of Manifold. MIE 330 With 1/8" Vent: Toward Front of Manifold MIE 330 Without Vent: Either Way. d - Exhaust Elbow Figure 4. MIE 228/255/330 Without Closed Cooling and Without Distribution Block a - Rear of Manifold Body b - Distribut on Block c - Gasket - Wide Part Toward Front of Manifold d - Gaskets - Wide Part Toward Rear of Manifold e - Plate (With 1/8" Vent Hole) - Wide Part Toward Rear of Manifold Figure 5. MIE 228/255 V-Drive Without Closed Cooling and With Distribution Block 90-95693 485 EXHAUST SYSTEM - 5A-15 3. Using new gasket, install manifold. Torque to specifications. 4. Starboard Manifold: a. Install water separating fuel filter. Connect fuel lines and tighten securely. b. Install slave solenoid and bracket. Tighten fasteners securely. Fort Manifold: a. Install alternator bracket. Tighten bolts securely. b. Install alternator and adjust belt tension. Tighten all fasteners securely. 5. Reconnect exhaust and water hoses. Tighten clamps securely. 6. Reconnect battery cables to battery. Tighten securely. 7. Start engine and check for fuel, exhaust and water leaks. a - Rear of Manifold Body b - Distribution Block c - Gaskets - Wide Part Toward Front of Manifold d - Gaskets - Wide Part Toward Rear of Manifold e - Plate (With 1/8" Vent Hole)-Wide Part Toward Rear of Manifold Figure 6. MIE 228/255 V-Drive With Closed Cooling and With Distribution Block 07019A a - Port Distribution Block b - Starboard Distribution Block c - Cast Arrow (Must Point Down) d - Gasket (Install One Above and One Below Each Block e - Hose Fitting (Must Point Inward) Figure 7. MIE 330 V-Drive With Closed Cooling and With Distribution Block 10615 5A-16 - EXHAUST SYSTEM 90-95693 485 SECTION 5 - EXHAUST SYSTEM PART B - EXHAUST RISERS INDEX Page Kit Identification 5B-1 Torque Specifications 5B-1 Sealants 5B-1 53452A2 - 6" Riser Kit 5B-2 57952A2 - 6" Riser Kit 5B-3 57952A4 - 6" Riser Kit 5B-5 57952A5 - 6" Riser Kit 5B-5 61811A4 - 3" Riser Kit 5B-6 61851A1 - 3" Riser Kit 5B-7 61851A2 - 3" Riser Kit 5B-8 61851A3 - 3" Riser Kit 5B-10 93320A2 - 3" Riser Kit 5B-11 93322A2 - 6" Riser Kit 5B-12 NOTICE For exhaust system recommendations, refer to "Section 5, Part C". KIT IDENTIFICATION MODEL 3" RISER 6" RISER MCM 120 (Note 1) (Note 1) MCM 120R 61851 A3 57952A5 MCM 140 61851A2 57952A2 MCM 140R 61851 A3 57952A5 MCM 165 61851A2 57952A2 MCM 470 61851A2 57952A2 MCM 470R (Note 1) (Note 1) MCM 485 (Note 1) (Note 1) MCM 488R (Note 1) (Note 1) MCM 898 61851A2 57952A2 MCM 898R 93320A2 93322A2 MCM 228 61851A2 57952A2 MCM 228R 93320A2 93322A2 MCM 260 61851A2 57952A2 MCM 260R 93320A2 93322A2 MCM 330 61811A4 53452A2 MCM 330 (B-W) 93320A2 93322A2 MCM 370/400 61811A4 53452A2 MIE 470 61851A1 57952A4 MIE 228 61851A2 57952A2 MIE 230 93320A2 93322A2 MIE 255 61851A2 57952A2 MIE 260 93320A2 93322A2 MIE 330 61811A4 53452A2 MIE 340 93320A2 93322A2 NOTE 1: Riser Kits not available for this model. TORQUE SPECIFICATIONS Fastener Location Lbs. Ft. (N.m) Exhaust Elbow 20-25 (27-34) Exhaust Riser 20-25 (27-34) SEALANTS SEALANTS 92-34227-1 Quicksilver Perfect Seal 90-95693 485 EXHAUST SYSTEM - 5B-1 53452A2 - 6" RISER KIT REPLACEMENT 1. Drain exhaust elbow and exhaust manifold. 2. Remove fasteners, then elbow and riser. 3. Clean all gasket surfaces. 4. Using Perfect Seal on both sides of new gaskets, install riser and elbow as shown in f igure 1, 2 or 3. IMPORTANT: Models with Stainless Steel Separator Plate: Separator plate must be installed as shown or steam pocket will form in exhaust manifold. 5. Torque fasteners to specifications. 6. Tighten hose clamps securely. 7. Closed Cooling System: Refill closed cooling svstem. 8. Check for leaks after starting engine. 12096 a - Stainless Steel Separator Plate with Gasket on Each Side b - Lockwashers and Nuts (4) c - 6" Riser d - Dram Plug - Down and Toward Front of Boat e - Screw. Lockwasher and Nut (4) f - Gasket Figure 1. MCM 330 a - Stainless Steel Separator Plate with Gaskets on Each Side (Note 1) b - Lockwashers and Nuts (4) c - Drain Plug - Down and Toward Front of Boat d - 6" Riser e - Gasket f - Screw. Lockwasher and Nut (4) NOTE 1: On engines equipped with Closed Cooling System water distribution blocks, block will be installed between exhaust manifold ano riser (instead of separator plate) with a gasket on each side (Figure 4) Figure 3. MIE 330 a - Gasket b - Lockwashers and Nuts (4) c - Drain Plug - Down and Toward Front of Boat d - 6" Riser e - Gasket f- Screws, Lockwashers and Nuts (4) Figure 2. MCM 370/400/400 Cyclone 5B-2- EXHAUST SYSTEM a - Fitting - Toward Center of Engine b - Arrow - Pointing Down c - Gasket on Each Side Figure 4. Distribution Block 15053 57952A2 - 6" RISER KIT REPLACEMEN T 5. Torque fasteners to specifications. 6. T ighten hose clamps securely. 1. Drain exhaust elbow and exhaust manifold. 7. Closed Cooling System: Refill closed cooling system. 2. Remove fasteners, then elbow and riser. 8. Check for leaks after starting engine. 3. Clean all gasket surfaces. 4. Using Perfect Seal on both sides of new gaskets, install riser and elbow as shown in Figure 1 or 3. IMPORTANT: Models with Stainless Steel Separator Plate: Separator plate must be installed as shown or steam pocket will form in exhaust manifold. 12398 a - MCM 140/165: Gasket - Wide Part Toward FRONT of Manifold. MCM 470/898/228/260: Stainless Steel Separator Plate with Gasket on Each Side - Wide Part Toward FRONT of Manifold (Note 1) b - Lockwashers and Nuts (4) c- 6" Riser d - Drain Plug - Down and Toward Front of Manifold e - Screws and Lockwashers (4) f - Gasket NOTE 1: MCM 898/228/260 equipped with Closed Cooling System water distribution blocks, block will be installed between exhaust manifold and riser (instead of separator plate) with a gasket on each side. (Figure 2) Figure 1. MCM 140/165/470/898/228/260 90-95693 485 EXHAUST SYSTEM - 5B-3 a - Distribution Block (Water Passages Toward Manitold) b - Wide Part of Gasket Forward c - Hose Fitting Forward Figure 2. MCM 898/228/260 Engines with Closed Cooling System NOTES: 1) MIE 228/255 V-Drives equipped with water distribution blocks, block will be installed between exhaust manifold and riser I instead of separator plate) with a gasket on each side. CFigure 4 or 5) 2) On models with water distribution block- Look at water passages in block and riser. Install riser (and gaskets) so water passages line up with passages in block. 07019A a - Rear of Manifold Body b - Distribution Block c - Gasket - Wide Part Toward Front of Manifold d - Gaskets - Wide Part Toward Rear of Manifold e - Plate (with 1/8" Vent Hole) - Wide Part Towa-d Rear of Manifold Figure 4. MIE 228/255 V-Drive Without Closed Cooling and With Distribution Block a - Stainless Steel Sepa*ator Plate with Gasket on Each S de Wide Part Toward FRONT of Manifold (Note 1) b - Lockwashers and Nuts (4) c - Drain Plug - Down and Toward Front of Manifold (Note 2) d - 6" Riser e - Gasket - Make Sure Wide of Gasket is Over Wide Part of Riser f - Screws and Lockwashers (4) Figure 3. MIE 228/255 5B-4 - EXHAUST SYSTEM a - Rear of Manifold Body b - Distribution Block c - Gasket - Wide Part Toward Front of Mani;old d - Gaskets - Wide Part Toward Rear of Manifold e - Plate (without 1/8" Vent Hole) - Wide Part Toward Rear of Manifold Figure 5. MIE 228/255 V-Drive With Closed Cooling and With Distribution Block 57952A4 - 6" RISER KIT REPLACEMENT 1. Drain exhaust elbow and exhaust manifold. 2. Remove fasteners, then elbow and riser. 3. Clean all gasket surfaces. IMPORTANT: Gaskets, exhaust elbow riser and distribution block MUST BE installed correctly (as described in steps 4, 5, 6 and 7) or water will leak into exhaust manifold during operation. 4. Coat both sides of one gasket (gasket with water passages) with Perfect Seal, then position gasket on exhaust manifold being certain that passages in gasket align with passages in manifold. Reinstall distribution block on manifold, being certain that bv-pass hose connection is toward front of boat, as shown in Figure 1. 5. Coat both sides of gasket (gasket without water passages) with Perfect Seal, then position gasket on water distribution block. Position gasket so that large opening is centered over exhaust passage. 6. Place exhaust elbow riser on water distribution block with drain plug downward and toward front of boat. Torque nuts a - Gasket (with Water Passages) to specifications. b - Water Distribution Block IMPORTANT: Gasket (with water passages) MUST c - Gasket (without Water Passages) d - Studs BE installed on top of riser. DO NOT install gasket e - Nuts and Lockwashers (without water passages) on top of riser, as this will f - Drain Plug cause riser to overheat. g - Exhaust Elbow Riser 7. Coat both sides of remaining gasket (gasket with water h - Gasket (with Water Passages) passages) with Perfect Seal, then position gasket on top of i - Studs j - Hose riser, being certain that passages in gasket align with pas- k - Hose sages in riser. Install exhaust elbow and torque nuts to specifications. Figure 1. MIE 470 with In-Line Transmission 8. Tighten hose clamps securely. 9. Refill closed cooling system. 10. Cheek for leaks after starting engine. 57952A5 - 6" RISER KIT REPLACEMENT 1. Drain exhaust elbow and exhaust manifold. 2. Remove fasteners, then elbow and riser. 3. Clean all gasket surfaces. 4. Using Perfect Seal on both sides of new gaskets, install riser and elbow as shown in Figure 1. IMPORTANT: Gaskets MUST BE installed as shown in Figure 1. 5. Torque fasteners to specifications. 6. l ighten hose clamps securely. 7. Check for leaks after starting engine. Figure 1. MCM 120R/140R 90-95693 485 EXHA JST SYSTEM - 5B 61811A4 - 3" RISER KIT REPLACEMENT 1. Drain exhaust elbow and exhaust manifold. 2. Remove fasteners, then elbow' and riser. 3. Clean all gasket surfaces. 4. Using Perfect Seal on both sides of new gaskets, install riser and elbow as shown in Figure 1. 2 or 3. IMPORTANT: Models with Stainless Steel Separator Plate: Separator plate must be installed as shown or steam pocket will form in exhaust manifold. 5. Torque fasteners to specifications. 6. Tighten hose clamps securely. 7. Closed Cooling Svstem: Refill closed cooling svslem. 8. Check for leaks af:er starting engine. a - Gasket b - Drain Plug - Down and Toward Front of Boat c - 3 ' Riser d - Gasket e - Lockwasher and Nut (4) Figure 2. MCM 370/400/400 Cyclone a - Stainless Steel Separator Plate with Gaskets on Each Side b - Drain Plug - Down and Toward Front of Boat c - 3" Riser d - Gasket e - Lockwasher and Nut (4) Figure 1. MCM 330 a - Stainless Steel Separator Plate with Gaskets on Each Side (Note 1) b - Drain Plug - Down and Toward Front of Boa; c - 3" Riser d - Gasket e - Lockwasher ard Nut (4) NOTE 1: On engines equipped with Closed Cooling System water distribution blocks, block will be installed between exhaust manifold and riser (instead of separator plate) with a gasket on each side. (Figure 4) Figure 3. MIE 330 5B-6 - EXHAUST SYSTEM 90-95693 a - Fitting - Toward Center of Engine b - Arrow - Pointing Down c - Gasket on Each Side Figure 4. Distribution Block 61851A1 -3 " RISER KIT REPLACEMENT 1. Drain exhaust elbow and exhaust manifold. 2. Remove fasteners, then elbow and riser. 3. Clean all gasket surfaces. 4. Using Perfect Seal on both sides of new gaskets, install riser and elbow as shown in Figure 1 or 2. IMPORTANT: Install gaskets so that large end is toward front of boat. Install riser with drain plug end downward and plug toward front of boat. Riser and gaskets MUST BE installed as indicated. 5. Torque fasteners to specifications. 6. Tighten hose clamps securelv. 7. Refill closed cooling system. 8. Check for leaks after starting engine. a - Nut (4) b - Lockwasher (4) c - Exhaust Elbow d - Gasket with Water Passages - Toward Front of Boat e - 3" Riser f - Pipe Plug g - Gasket without Water Passages - MUST BE Installed Between Riser and Distribution Block h - Distribution Block i - Stud (4) j - Exhaust Manifold k - Voltage Regulator-to-Exhaust Elbow Hose I - Clamp (2) m - Transmission Fluid Cooler-to-Exhaust Elbow Hose n - Clamp (2) Figure 1. MIE 470 with In-Line Transmission 15207 90-95693 485 EXHAUST SYSTEM - 5B-7 a - Nut (4) b - Lockwashe- (4) c - Exhaust Elbow d - Gasket with Water Passages - Toward Front of Boat e - 3" Riser f - Pipe Plug g - Gasket without Water Passages - MUST BE Installed Between Riser and Distribution Block h - Stud (4) i - Distributor Block and Exhaust Manifold j - Voltage Regulator-to-Exhaust Elbow Hose k - Clamp (2) I - Transmission Fluid Cooler-to-Exhaust Elbow Hose m - Clamp (2) Figure 2. MIE 470 with V-Drive Transmission 61851A2 - 3" RISER KIT 5. Torque fasteners to specifications. REPLACEMENT 6. T ighten hose clamps securely. 1. Drain exhaust elbow and exhaust manifold. 7. Closed Cooling Svsiem: Refill closed cooling svstem. 2. Remove fasteners, then elbow and riser. 8. Check for lea^ after starting engine. 3. Clean all gasket surfaces. 4. I sing Perfect Seal on both sides of new gaskets, install riser and elbow as shown in Figure 1 or 3. IMPORTANT: Models with Stainless Steel Separator Plate: Separator plate must be installed as shown or steam pocket will form in exhaust manifold. 12719 a - MCM 14C/165: Gasket - Wide Part Toward FRONT of Manifold MCM 470/898/228/260 Stainless Steel Separator Plate with Gaskets on Each Side - Wide Part Toward FRONT of Manifold (Note 1) b - 3" Riser c - Dram Plug - Down and Toward Front of Manifold d - Gasket e - Lockwashers and Nuts (4) NOTE 1: MCM 898/228/260 equipped with Closed Cooling System water distribution blocks, block will be installed between exhaust manifold and riser (instead of separator plate) with a gasket on each side. (Figure 2) Figure 1. MCM 140/165/470/898/228/260 5B-8 - EXHAUST SYSTEM 90-95693 07019A a - Rear of Manifold Body b - Distribution Block c - Gasket - Wide Part Toward Front of Manifold d - Gaskets - Wide Part Toward Rear of Manifold a - Distribution Block (Water Passages Toward Manifold) e - Plate (with 1/8" Vent Hole) - Wide Part Toward Rear of Manifold b - Wide Part of Gasket Forward c - Hose Fitting Forward Figure 4. MIE 228/255 V-Drive Without Closed Cooling and With Distribution Block Figure 2. MCM 898/228/260 Engines with Closed Cooling System a - Stainless Steel Separator Plate with Gaskets on Each Side Wide Part Toward FRONT of Manifolc (Note 1) b - Drain Plug - Down and Toward Front of Manifold (Note 2) c - 3" Riser d - Gas«et - Make Sure Wide Part of Gasket is Over Wide Part of R ser e - Lockwasher and Nut (4) NOTES 1) MIE 228/255 V-Dnves equipped with water distribution blocks, block will be installed between exhaust manifold and riser (instead of separator plate) with a gasket on each side. (Figure 4 or 5) 2) On models with water distribution block; Look at water passages in block and riser. Install riser (and gaskets) so water passages line up with passages in block. Figure 3. MIE 228/255 12718 90-95693 485 EXHAUST SYSTEM - 5B-9 07019A 07019A a - Rear of Manifold Body b - Distribution Block c - Gasket - Wide Part Toward Front of Manifold d - Gaskets - Wide Part Toward Rear of Manifold e - Plate (without 1/8" Vent Hole) - Wide Part Toward Rear of Manifold Figure 5. MIE 228/255 V-Drive With Closed Cooling and With Distribution Block 61851 A3 - 3" RISER KIT REPLACEMENT 1. Drain exhaust elbow and exhaust manifold. 2. Remove fasteners, then elbow and riser. 3. Clean all gasket surfaces. 4. I sing Perfect Seal on both sides of new gaskets, install riser and elbow as shown in Figure 1. IMPORTANT: Gaskets MUST BE installed as shown in Figure 1. 5. Torque fasteners to specifications. 6. Tighten hose clamps securely. 7. Check for leaks after starting engine. Figure 1. MCM 120R/140R 206-H 5B-10 - EXHAUST SYSTEM 93320A2 - 3" RISER KIT REPLACEMENT Drain exhaust elbow and exhaust manifold. Remove ignition amplifier or shift plate (MCM onlv). Remove fasteners, then elbow and riser. Clean all gasket surfaces. I sing Perfect Seal on both sides of new gaskets, install riser and elbow as shown in Figure 1 or 2. IMPORTANT: Gaskets, restrictor plate (or separator plate and riser must be installed as shown in Figure 1 or 2. IMPORTANT: If engine is equipped with closed cooling, stainless steel separator plate must be installed below 3" risers. If plate is installed above 3" riser, a steam pocket will form in exhaust manifolds during operation. 6. Torque fasteners to specifications. F.lbow with ignition amplifier: Reinstall ignition amplifier and wiring harness mounting bracket onto exhaust elbow using original attaching hardware. Be sure to reconnect amplifier and wiring harness ground wires to one of the attaching screws and that amplifier spacers are installed between amplifier and exhaust elbow. Tighten screws securely. 8. Elbow with shift plate (MCM only): Reinstall shift plate. Tighten fasteners securely. Readjust shift cables as outlined in "Stern Drive Service Manual". 9. Tighten hose clamps securelv. 10. Closed Cooling System: Refill closed cooling system. 1 I. Check for leaks after starting engine. a - Gasket (27-87105) l_or c b - Stainless Steel Separator Plate ' c- Separator Gasket (27-41811) - DO NOT Use Perfect Seal on Gasket d - Gasket (27-87105) e - Drain Plug - Down and Toward Rear of Boat f - Stud [16-34713, 3/8" x 6-1/2" (165mm)] - Port Manifold with Remote Oil Filter (if Equipped) Figure 2. Engines with Closed Cooling a - Gasket (27-87105) . or C b - Stainless Steel Restrictor Plate c - Restrictor Gasket (27-41813) - DO NOT Use Perfect Seal on Gasket d - Gasket (27-87105) e - Drain Plug - Down and Toward Rear of Boat f - Stud [16-34713, 3/8" x 6-1/2" (165mm)] - Port Manifold with Remote Oil Filter (if Equipped) Figure 1. Engines without Closed Cooling 148-hr3 148-hh4 90-95693 485 EXHAUST SYSTEM - 5B-11 93322A2 - 6" RISER KIT REPLACEMENT 1. Drain exhaust elbow and exhaust manifold. 2. Remove ignition amplifier or shift plale (MCM only). 3. Remove fasteners, then elbow and riser. 4. Clean all gasket surlaces. 5. Using Perfect Seal on both sides of new gaskets, install riser and elbow as shown in Figure 1 or 2. IMPORTANT: Gaskets, restrictor plate (or separa tor plate) and riser must be installed as shown in Figure 1 or 2. IMPORTANT: If engine is equipped with closed cooling, stainless steel separator plate musl be installed below 6" risers. If plate is installed above 6" riser, a steam pocket will form in exhaust manifolds during operation. 6. Torque fasteners to specifications. 7. Elbow with ignition amplifier: Reinstall ignition amplifier and wiring harness mounting bracket onto exhaust elbow using original attaching hardware. Be sure to reconnect amplifier and wiring harness ground wires to one of theattaching screws and that amplifier spacersare installed between amplifier and exhaust elbow. Tighten screws securely. 8. Elbow with shift plate (MCM only): Reinstall shift plate. Tighten fasteners securely. Readjust shift cables as outlined in "Stern Drive Service Manual". 9. Tighten hose clamps securely. 10. Closed Cooling System: Refill closed cooling system. 11. Check for leaks after starting engine. 148-hr5 Gasket (27-87105) or C b - Stainless Steel Restrictor Plate- c - Restrictor Gasket (27-41813) - DO NOT Use Perfect Seal on Gasket d - Gasket (27-87105) e - Drain Plug - Down and Toward Rear of Boat f - Screw [10-26487. 3/8"-16 x 1-1/8" (29mm)] - Starboard Riser with Wiring Harness Bracket Figure 1. Engines without Closed Cooling 5B-12 - EXHAUST SYSTEM 90-95693 a - Gasket (27-87105) b - Stainless Steel Separator Plate —r or c - Separator Gasket (27-41811) - DO NOT Use Perfect Seal on Gasket d - Gasket (27-87105) e - Drain Plug - Down and Toward Rear of Boat f - Screw [10-26487. 3/8"-16 x 1-1/8" (29mm)] - Starboard Riser with Wiring Harness Bracket Figure 2. Engines with Closed Cooling 90-95693 485 EXHAUST SYSTEM - 5A-13 SECTION 5 - EXHAUST SYSTEM PART C - EXHAUST COLLECTORS INDEX Page Torque Specifications 5C-1 Sealants 5C-1 Exhaust System Requirements 5C-2 MCM Engines with Thru Drive Unit Exhaust 5C-2 MCM Engines with Thru Transom Exhaust .. 5C-2 MCM 120-330 (B-W) Engines 5C-3 MIE Inboard Engines 5C-4 Exhaust Component and Shutter Replacement 5C-5 MCM 120/140/165/470 5C-5 MCM 485 5C-7 MCM 120R/140R 5C-8 MCM 120R/140R Driveshaft Extension Models 5C-9 MCM 47CR/488R 5C-11 MCM 898/228/260 5C-13 MCM 898R/228R/260R 5C-14 MCM 898/898R/228/228R/260/260R Driveshaft Extension Models 5C-16 MCM 330/330 (B-W) 5C-18 MCM 3" Exhaust Hose Extension Kit 32-62364A1 5C-20 MCM 6" Exhaust Hose Extension Kit 32-59077A1 5C-20 Thru Transom Exhaust Flange 5C-20 MIE 228/230/255/260 Single Exhaust Kit 48640A2 5C-21 SECTION 5 - EXHAUST SYSTEM PART C - EXHAUST COLLECTORS INDEX Page Torque Specifications 5C-1 Sealants 5C-1 Exhaust System Requirements 5C-2 MCM Engines with Thru Drive Unit Exhaust 5C-2 MCM Engines with Thru Transom Exhaust .. 5C-2 MCM 120-330 (B-W) Engines 5C-3 MIE Inboard Engines 5C-4 Exhaust Component and Shutter Replacement 5C-5 MCM 120/140/165/470 5C-5 MCM 485 5C-7 MCM 120R/140R 5C-8 MCM 120R/140R Driveshaft Extension Models 5C-9 MCM 47CR/488R 5C-11 MCM 898/228/260 5C-13 MCM 898R/228R/260R 5C-14 MCM 898/898R/228/228R/260/260R Driveshaft Extension Models 5C-16 MCM 33C/330 (B-W) 5C-18 MCM 3" Exhaust Hose Extension Kit 32-62364A1 5C-20 MCM 6" Exhaust Hose Extension Kit 32-59077A1 5C-20 Thru Transom Exhaust Flange 5C-20 MIE 228/230/255/260 Single Exhaust Kit 48640A2 5C-21 TORQUE SPECIFICATIONS Fastener Location Lbs. Ft. (N.m) Block Off Plate 20-25 (27-34) Exhaust Pipe to 20-25 Gimbal Housing (27-34) Exhaust Pipe to 20-25 Tee Pipe (27-34) Hose Clamps Securely Tee Pipe to Gimbal 20-25 Housing (27-34) Upper Exhaust Pipe to 20-25 Lower Exhaust Pipe (27-34) Water Shutter Screw/Nut Securely SEALANTS SEALANT S 92-86166 Quicksilver Bellows Adhesive 92-34227 Quicksilver Perfect Seal 90-95693 485 EXHAUST SYSTEM - 5C-1 EXHAUST SYSTEM REQUIREMENTS MCM ENGINES WITH THRU DRIVE UNIT EXHAUST Determine if exhaust elbow risers are required bv taking measurements "A " and B" in Figure 1. with boat at rest in the water and maximum load aboard. Subtract B" from A . If A ' minus "B " is less than specified in chart, select appropriate size exhaust elbow riser kit and exhaust extension kit that will correctk position exhaust elbow. a -From Waterline to Top of Transom b -From Highest Pcint on Exhaust Elbow to Top of Transom Figure 1. Exhaust Elbow Measurement Mode ModeMode l ll "A" Minus "B" Must Be In. (mm) or More MCM 120 12-1/2 (318) (Note 1) MCM 120R 11 (279) MCM 140 12-1/2 (318) MCM 140R 11 (279) MCM 165 12-1/2 (318) MCM 470 12-1/2 (318) MCM 470R 13 (330) (Note 1) MCM 485 13 (330) (Note 1) MCM 488R 13 (330) (Note 1) MCM 898 12-7/8 (327) MCM 898R 13 (330) MCM 228 12-7/8 (327) MCM 228R 13(330) MCM 260 12-7/8 (327) MCM 260R 13 (330) MCM 330 15-3/8 (391) MCM 330 (B-W) 13 (330) NOTE 1: Exhaust Elbow Riser Kits are not available for this model. MCM ENGINES WITH THRU TRANSOM EXHAUST 5C-2 -EXHAUST SYSTEM 90-95693 Determine if exhaust elbow risers are required by taking measurements "A " and "B" in Figure 2, with boat at rest in the water and maximum load aboard. Subtract "B" from "A". If "A" minus "B" is less than specified in chart, select appropriate size exhaust elbow riser kit that will correctly position exhaust elbows. Also, a W (13mm) per foot (305mm) downward drop must exist in the exhaust hose from the engine exhaust elbow to the transom outlet. Exhaust hoses must not restrict discharge water flow at exhaust elbow. (Figure 3) Transom outlet should have internal water shutter; and outlet covers ("Flappers'") on outside. IMPORTANT: For MCM 120-330 (B-W) engines, also refer to "MCM 120-330 (B-W) Engines", following. a - Correct b - Incorrect Figure 3. Hose Connection a - From Watertine to Top of Transom b - From Highest Point on Exhaust Elbow to Top of Transom Figure 2. Exhaust Elbow Measurement Model "A" Minus "B" Must Be In. (mm) or More MCM 370/400/ 400 Cyclone 15 (381mm) a - Block Off Plate P/N 97350 Figure 4. MCM 120R-260R Only MCM 120-330 (B-W) Engines There arc no kits to convert these engine from thru drive to thru transom exhaust. Bv using block off plates, inboard exhaust elbows, exhaust hoses and transom outlet fit tings, ma n\ engines have been converted to thru transom exhaust. In addition to the preceding information, the follow ing should be adhered to: • hxhaust Elbow Measurement must be checked. (Figure l) • Block of plates (for drive exhaust svstem) must be able to prevent water from entering the boat. • Exhaust bellows (between gimbal housing and bell housing) should be removed to allow propeller to draw air. • MCM 120R-260R Engines Onlv: Refer to Figure 4. • MCM 898R/228R/260R Engine Only: Refer to Figure 5. 15089 90-95693 485 EXHAUST SYSTEM - 5B-3 1. Exhaust Elbow (without stainless steel lube): MIE INBOARD ENGINES MUST BE CHANGED. Order: (2) 98504A3 Exhaust Elbows (2) 27-41813 Exhaust Elbow Restrictor Gaskels MOTE: If engine has stainless steel restrictor plate (99208A1). discard plate when using 27-41813 Restrictor Gaskets. 2. 3" or 6" Exhaust Elbow Riser Kits: If these kils are going lo be used, restrictor gasket (a) Ml ST BE INSTALLED between the riser and exhaust elbow. 27-87105 gasket (b) is installed at location shown. Figure 5. MCM 898R/228R/260R Only It is the responsibility of the boat manufacturer or installing dealer to properly locate the engine and install the exhaust system. Improper installation may allow water to enter the exhaust manifolds and combustion chambers and severely damage the engine. Damage caused by water in the engine will not be covered by MerCruiser Warranty, unless this damage is the result of defective part(s). System iavout and construction musl prevenl cooling svslem discharge water Irom flowing back into engine and also must prevenl seawaler from entering engine via exhaust svstem. Ml cooling svslem water is discharged ihru openings which are located inside the exhaust elbows. I o pre\ cut discharge water from How ing ba: k into I he engine, the exhaust hoses and pipes must nut be higher llian exhaust elbows al an\ point. The exhausl oullel (for routing exhaust to outside of boat) must be located so that a minimum of V2" (13mm) per 1' (305mm) downward pitch (drop) exists in the exhaust hose or pipe from the engine exhaust elbow to the outlet, with a minimum drop of 4" (100mm) overall. (This is an American Boat & Yacht Council recommendation.) The drop must be constant so that a low spot does not exist at any point in the exhaust hose or pipe. Exhausl outlet must be slightly above ihe waterline with boat at rest in the waterand full load aboard. Exhausl oullel should be equipped with an inlernal water shuller lo pre\enl seawaler from running hack into exhausl svslem. II ihru-lransomexhausl oullelsare used. ti^c of an exhausl flapper oil each oullel also 1- recommended. Determine il exhausl elbow risers arc required l>\ laking measurements \ and B in Figu re (). willi boat a I res I 111 I he water and maximum load aboard. Sublracl B I rom \ If \ minus B is less llian specified in chart, selecl appropriale size exhausl elbow ri~er kit llial will correcllv position exhausl elbows. a - From Waterline to Reference Point b - From Highest Point on Exhaust Elbow to Same Reference Point Figure 6. Exhaust Elbow Measurement 5C-4 - EXHAUST SYSTEM 90-95693 MIE 330/340 MINIMUM EXHAUST HOSE SIZES Dual Exhaust 3" (76mm) Single Exhaust 5" (127mm) Model "A" Minus "B" Must Be In. (mm) or More MIE 470 14 (356) MIE 228 14 (356) (Note 1) MIE 230 13 (330) MIE 255 14 (356) (Note 1) MIE 260 13 (330) MIE 330 14 (356) MIE 340 13 (330) 4. Exhaust hoses must be connected t<- exhaust elbows that tlie\ do not restrict the flow of discharge water from the elbow. (Figure 7) If hoses are connected incorrectly, discharge water from exhaust elbow will not flow around entire inside diameter of hose. This will cause a hot spot in the hose which ma\ evenluallv burn thru. NOTE 1: V-Drive Models; 16" (4C6mm) 3. System must not cause excessive back pressure. Back pressure Ml ST\0Texceed4" (100mm) of mercurv when measured with a mercurv manometer at exhaust elbow outlets. Minimum exhaust hose sizes are given in charts. MIE 470 MINIMUM EXHAUST HOSE SIZE Single Exhaust 3" (76mm) j@ L-MSzji * MIEMINIMUM 228/230/255/260 EXHAUST HOSE SIZES Dual Exhaust 3" (76mm) Single Exhaust 4" (102mm) • Correct • Incorrect Figure 7. Hose Connection EXHAUST COMPONENT and SHUTTER REPLACEMENT MCM 120/140/165/470 Shutter Replacement IMPORTANT: Engine does not have to be removed to replace shutters, however, exhaust elbowhave to be removed to remove exhaust bellows. 1. Loosen hose clamps on exhaust bellows and remove bellows. 2. (.hisel rivets away from one (most easily accessible) support member and remove support member. (Fisiure l) a - Exhaus: Elbow b - Chisel c - Rivet Figure 1. Removing Shutter may - 90-95693 485 EXHAUST SYSTEM - 5C-5 3. Applv silicone sealer lo one end of new shutter, then place end in support member that was removed in Step 2. 4. Bend tongues of shutter away from center support bar and point them down exhaust elbow. Place other end of shutter (after applying silicone to end) in support member (still in exhaust pipe), while positioning shutter assembly so that mounting holes line up. (Figure 2) 5. Secure support member with 10-32 x W (13mm) round head screws and nuts. Be sure that head of screw is to the outside of exhaust elbow. 6. Place hose clamps over both ends of exhaust bellows, then reposition between engine and exhaust pipe and tighten hose clamps. a - Support Member Removed c - Silicone Sea er in Disassembly d - Support Menber b - Shutter - Opens Downward e - Align These Holes Figure 2. Replacing Shutter Exhaust Pipe Replacement 1. Remove stern drive unit. 2. Remove engine. 3. Remove screws and lockwashers lhal secure exhaust pipe to gimbal housing. (Figure 3) 4. Remove exhaust pipe and "()" ring. r>. Clean mating surfaces on pipe and gimbal housing. 6. Place "0 ring in groove of gimbal housing. (Figure 4) 7. Reinstall exhausl pipe with screws and lockwashers. tor<| uing them to specifications. Be certain lhal "()" ring remains seated in groove, properly sealing joint to prevent leakage. (Figures 3 and 4) 8. Reinstall engine and stern drive unit. a - Exhaust Pipe b - Screws Figure 3. Exhaust Pipe a - Mating Surface b - "O" Ring in Groove Figure 4. Exhaust Pipe Mounting Surface 5C-6 - EXHAUST SYSTEM 90-95693 MCM 485 Upper Exhaust Pipe and Shutter Replacement IMPORTANT: Engine does not have to be removed. I. Remove screws and loosen exhaust bellows clamps. (Figure I) a - Clamps b - Screws and Washers (3) c - Gasket Figure 1. Upper Exhaust Pipe and Bellows 2. Replace shutters as outlined in steps 2. 3. ! and 5 of "Shutter Replacement. MCM 120/140/165/470". I sing new gaskel. place clamps over exhaust bellows, then install upper exhaust pipe. (Figure 1) 1. I cirque screws to specification. Tighten clamps securelv. Exhaust Pipe Replacement 1. Remove stern drive unit. 2. Remove upper exhaust pipe, then engine. 3. Keinov e screws and lockwashers I hat secure lower exhaust pipe t" gimbal housing. (Figure 2) a - Screws and Lockwashers Figure 2. Lower Exhaust Pipe 4. Remove exhaust pipe and "()' ring. 5. Clean mating surfaces on pipe and gimbal housing. 6. Place "O " ring in groove of gimbal housing. I1 igure 3) 7. Reinstall lower exhaust pipe with screws and lockwasher. torquing them to specifications. He certain that "((" ring remains seated in groove, properlv sealing joint to prevent leakage. 8. Reinstall engine and stern drive unit. 9. Reinstall upper exhaust pipe. 11135A a - "O" Ring in Groove b - Mating Surface Figure 3. Exhaust Pipe Mounting Surface 90-95693 485 EXHAUST SYSTEM - 5C-7 4. Replace shutter (in lower pipe), as shown in Figure 3 or 4. MCM 120R/140R 5. Flange Connection Models (Figure 3): Upper Exhaust Pipe and Shutter Replacement a. Make sure "0 " ring is in groove. b. Place clamps over exhaust bellows, then install upper IMPORTANT: Engine does not have to be removed, exhaust pipe. Be certain that "0 " ring remains seated however, exhaust elbow may have to be removed. in groove, properly sealing joint to prevent leakage. 1. Loosen exhaust bellows clamps. c. Torque screws to specifications. Tighten clamps 2. Remove screws and lockwashers (Figure 1) or hose clamps. securely. (Figure 2) Connector Hose Models (Figure 4): 3. Remove upper exhaust pipe. a. Coat both mating surfaces of hose and lower pipe with Bellows Adhesive. Allow to dry and then slide hose on lower pipe. Tighten clamps securely. b. Place clamps over bellows and connector hose, then install upper exhaust pipe. c. Making sure all clamps are contacting exhaust elbow, upper pipe and lower pipe, tighten clamps securely. 16741 a - Shutter - Opens Downward b - Retainer - Slots Up c - "O" Ring - In Groove of Lower Pipe Figure 3. Flanged Connection a - Clamps b - Connector Hose Figure 2. Connector Hose Connection a - Clamps b - Screws and Lockwashers (3) Figure 1. Flanged Connection 17308 5C-8 - EXHAUST SYSTEM 90-95693 a - Mating Surface b - "O" Ring Figure 6. Exhaust Pipe Mounting Surface 4. Remove exhaust pipe and * 0' ring. 5. Clean mating surfaces on pipe and gimbal housing. 6. Place "0 " ring in groove of gimbal housing. (Figure 6) 7. Reinstall lower exhaust pipe with screws and lockwashers, torquing them to specifications. Be certain lhat "0 " ring remains seated in groove, properlv sealing joint to prevenl a - Connector Hose - Remove to Change Shutters leakage. b - Clamps (2) 8. Reinstall upper exhaust pipe, then engine. c - Grommet (2) 9. Reinstall stern drive unit. d - Shutter - Opens Downward Figure 4. Connector Hose Connection MCM 120R/140R DRIVESHAFT EXTENSION MODELS Lower Exhaust Pipe Replacement Shutter Replacement 1. Remove stern drive unit. 2. Remove engine, then upper exhaust pipe. 1. Loosen hose clamps on exhaust hose and remove screws 3. Remove screws and lockwashers that secure lower exhaust and lockwashers. (Figure 2) pipe to gimbal housing. (Figure 5) Remove exhaust pipe elbow. Remove water shutter, then retainer from tee pipe. Install retainer, ihen shutter as shown in Figure 2. Make sure mating surfaces are clean and "0 " ring is in groove. Reinstall exhaust pipe elbow with screws and lockwashers, torquing them to specifications. Be certain that "0 " ring remains seated in groove, properlv seal.ng joint to prevenl leakage. Tighten clamps securelv. Exhaust System Component Replacement To replace any component in system as shown in Figures 1 and 2. The following must be adhered to: • All mating joint surfaces must be c.ean. "0 rings must remain in groove to properlv seal joints 16747 to prevent leakage. Torque all screws and lockwashers to specifications. Tighten all clamps securely. a - Lower Exhaust Pipe b - Screws and Lockwashers (4) Figure 5. Lower Exhaust Pipe 90-95693 485 EXHAUST SYSTEM - 5C-9 '////// ^ '////// ^ a - Screws and Lockwashers b - Plate c - "O" Rinc d - Retainer - Slots Toward Inside of Tee Pipe e - Tee Pipe f - Retainer - Slots Facing Toward Outside of Tee Pipe g - Water Shutter - Opens Toward Inside of Tee Pipe h - Exhaust Pipe Elbow i - Clamps j - Exhaust Hose k - Exhaust Tube I - Ground Strap m - Exhaust Bellows Figure 2. Exhaust System Components 5C-10- EXHAUST SYSTEM 90-95693 MCM 470R/488R Upper Exhaust Pipe and Shutter Replacement IMPORTANT: Engine does not have to be removed, however, exhaust elbow may have to be removed. 1. Loosen exhaust bellows clamps. 2. Remove screws and lockwashers (Figure 1) or hose clamps. (Figure 2) 3. Remove upper exhaust pipe. Figure 2. Connector Hose Connection a - Clamps b - Screws and Lockwashers (3) Figure 1. Flanged Connection 16746 a - Clamps b - Connector Hose 90-95693 485 EXHAUST SYSTEM - 5A-11 4. Replace shutter (in lower pipe), as shown in Figure 3 or 4. 5. Flange Connection Models (Figure 3): a. Make sure "0 " ring is in groove. b. Place clamps over exhaust bellows, then install upper exhaust pipe. Be certain that "0 " ring remains seated in groove, properly sealing joint to prevent leakage. c. Torque screws to specification. Tighten clamps securely. Connector Hose Models (Figure 4): a. Coat both mating surfaces of hose and lower pipe with Bellows Adhesive. Allow to dry and then slide hose on lower pipe. Tighten clamps securely. b. Place clamps over bellows and connector hose, then install upper exhaust pipe. c. Making sure all clamps are contacting exhaust elbow, upper pipe and lower pipe, tighten clamps securely. a - Connector Hose - Remove to Change Shutters b - Clamps (2) c - Grommet (2) d - Shutter - Opens Downward Figure 4. Connector Hose Connection Lower Exhaust Pipe Replacement 1. Remove stern drive unit. 2. Remove engine, then upper exhaust pipe. 3. Remove screws and lockwashers that secure lower exhaust pipe to gimbal housing. (Figure 5) a - Lower Exhaust Pipe b - Screws and Lockwashers (4) Figure 5. Lower Exhaust Pipe a - Shutter - Opens Downward b - Retainer - Slots Up c - "O" Ring - In Groove of Lower Pipe Figure 3. Flanged Connection 5C-12 - EXHAUST SYSTEM 90-95693 4. Remove exhausl pipe and "0 " ring. 5. Clean mating surfaces on pipe and gimbal housing. 6. Place "0 " ring in groove of gimbal housing. (Figure 6) a - Mating Surface b - "O" Ring Figure 6. Exhaust Pipe Mounting Surface 7. Reinstall lower exhaust pipe with screws and lockwashers, torquing them to specifications. Be certain that "0 " ring remains seated in groove, properlv sealing joint to prevenl leakage. 8. Reinstall engine, then upper exhaust pipe. 9. Reinstall stern drive unit. MC M 898/228/260 Exhaust Pipe and Shutter Replacement IMPORTANT: If a long alien wrench is available, and limits of engine compartment allow access to exhaust pipe alien screws, then removal of stern drive unit and engine is not necessary. Only bellows clamps have to be loosened. 1. Remove stem drive unit. 2. Remove engine. 3. Remove exhaust pipe from tee pipe by removing 3 alien screws and lockwashers. (Figure 1) 4. Replace water shutter as shown in Figure 2. IMPORTANT: If engine has closed cooling water distribution blocks between exhaust manifold and exhaust elbow, exhaust bellows [P/N 72408,6-7/64" (155mm) long] must be used on engine. a - Screws - 3 Each Side b - Tee Pipe c - Exhaust Pipe Figure 1. Exhaust Pipe Removal a - "0" Ring b - Retainer - Installed First c - Shutter - Opens Toward Tee Pipe d - Slot (Facing Out) Figure 2. Replacing Shutter 5. Make sure 0" ring is in groove and mating surfaces are clean. 6. Install exhaust pipe. Be certain that "0 " ring remains seated in groove, properly sealing joint to prevent leakage. 7. Torque screws to specifications. 8. Reinstall engine. Tighten all clamps securely. 9. Reinstall stern drive unit. 90-95693 485 EXHAUST SYSTEM - 5C-13 Tee Pipe Replacement 1. Follow preceding instructions. 2. Remove screws and lockwashers (Figure 3). then remove tee pipe. a - Screws Securing Exhaust Assembly to Gimbal Housing Figure 3. Removing Tee Pipe 3. Mating surfaces must be clean and "0 " rings in grooves. (Figure 4) a - Mating Surface b - "O" Rings Figure 4. Mounting Surface 4. Install tee pipe lo gimbal housing. Be certain that "0 " rings remain seated in grooves, properly sealing joint to prevent leakage. 5. Torque screws to specifications. 6. Follow instruction as outlined in "Exhaust Pipe and Shutter Replacement" MC M 898R/228R/260R Shutter Replacement IMPORTANT: Engine does not have to be removed to change shutters. 1. Loosen clamps and remove exhaust pipe elbow and exhaust hose. (Figure 3) 2. Replace water shutter as shown in Figure 1. 3. Reinstall pipe elbow and hose. Tighten clamps securely. b - Shoulder Bushing c - Water Shutter - Install as Shown d - Shaft Figure 1. Shutter Replacement 5C-14 - EXHAUST SYSTEM 90-95693 Exhaust System Component Replacement 1. To replace any component in system as shown in Figures 2 and 3. The following must be adhered to: • All mating joint surfaces must be clean. • ' 0" ring must remain in groove to properly seal joint to prevent leakage. • Torque all screws and lockwashers to specifications. • Tighten all clamps securely. L-—' a - Mating Surface b - "O" Ring Figure 2. Exhaust Pipe Mounting Surtace a -Clamps b-Exhaust Bellows c -Exhaust Pipe Elbow - Early Models Use Casting 94443 On Both Sides. Later Models Jse Casting 94443 On Starboard Side and Casting 94444 On Port Side d -Exhaust Hose e -Water Shutters f -Screws and Lockwashers 9 -Exhaust Pipe - Refer to Part List for Correct One Figure 3. Exhaust System Components 90-95693 485 EXHAUST SYSTEM - 5A-15 MCM 898/898R/228/228R/260/260R DRIVESHAFT EXTENSION MODELS Shutter Replacement 1. Loosen hose clamps on exhaust hose and remove screws and lockwashers. (Figure 3) 2. Remove exhaust pipe elbow. 3. Remove water shutter, then retainer from tee piae. 4. Install retainer, then shutter as shown in Figure 3. 5. Make sure mating surfaces are clean and "O " ring is in groove. 6. Reinstall exhaust pipe elbow with screws and lockwashers, torquing them to specifications. Re certain that "O " ring remains seated in groove, properly sealing joint to prevent leakage. 7. Tighten clamps securely. Exhaust System Component Replacement 1. To replace any component in system as shown in Figures 1. 2 or 3. The following must be adhered to: • All mating joint surfaces must be clean. • "0 " rings must remain in groove to properly seal joints to prevent leakage. • Torque all screws and lockwashers to specifications. • Tighten all clamps securely. a - Mating Surface b - "O" Ring Figure 2. Exhaust Tee Pipe Mounting Surface Later Models a - Mating Surface b - "O" Rings Figure 1. Exhaust Tee Pipe Mounting Surface Early Models 5C-16 - EXHAUST SYSTEM 90-95693 a - Screws and Lockwashers b - Tee Pipe c - "O" Ring d - Retainer - Slots Facing Out e - Water Shutter - Opens Toward Inside of Tee Pipe f - Exhaust Pipe Elbow g - Clamps h - Exhaust Hose i - Exhaust Tube j - Ground Strap k - Exhaust Bellows Figure 3. Exhaust System Components 90-95693 485 EXHAUST SYSTEM - 5C-17 MC M 330/330 (B-W) Exhaust Pipe and Shutter Replacement MCM 330 IMPORTANT: Engine does not have to be removed to change shutters. 1. Loosen clamps and remove exhaust pipe elbow screws and lockwashers. (Figure 1 or 3) Remove exhaust pipe elbow. 2. Replace water shutter as shown in Figure 3. 3. Make sure mating surfaces are clean. 4. Reinstall exhaust pipe elbow w ith screws and lockwashers, torquing them to specifications. Be certain that "0 " ring remains seated in groove, properly sealing joint to prevent leakage. 5. Tighten clamps securely. a - Screws and Lockwashers (3) Figure 1. MCM 330 a - Mating Surfaces - Must Be Clean Figure 2. Transom Plate Exhaust System Component Replacement MCM 330 (B-W) 1. To replace anv component in system as shown in Figures 2 and 3. The following must be adhered to: • All mating joint surfaces must be clean. • "O " ring must remain in groove to properly seal joint to prevent leakage. • Torque all screws and lockwashers to specifications. • Tighten all clamps securely. 5C-18 - EXHAUST SYSTEM 90-95693 a - Reta ner - Slots Toward Exhaust Pipe Elbow b - Shutters - Opens Toward Transom Plate c - "O" Ring d - Exhaust Pipe Elbow e - Screws and Lockwashers (3 Per Side) f - Clamps g - Exhaust Hose h - Exhaust Pipe i - Exhaust Bellows Figure 3. MCM 330 (B-W) 90-95693 485 EXHAUST SYSTEM - 5A-19 MCM 3" EXHAUST HOSE EXTENSION KIT THRU TRANSOM EXHAUST FLANGE 32-62364A1 Shutter Replacement ]. Remove exhaust hose clamps, then hose. 2. Chisel rivets away from both support members. (Figure 1) 3. Install new shutter as shown in Figure 1. Tighten screws and nut securely. 4. Reinstall exhaust hose. Tighten clamps securely. a - Original Exhaust Elbow or Exhaust Tube b - Original Clamps c - Original Exhaust Bellows - MCM 898/228/260 (With End 05090 Exhaust Outlet in Manifold) Only: If Engine Is Equipped With a - Shutter Hinge Closed Cooling Wa:er Distribution Blocks, Exhaust Bellows b - Water Shutter - Opens Toward Outside of Boat [72408. 6-7/64" (155mm)] Must Be Used c - Support Member d - Original Exhaust Pipe d - Rivets (4) e - Clamps - From Kit f - Exhaust Hose [3-1/4" (83mm)] - From Kit Figure 1. Shutter Replacement g - Exhaust Tube [3" (76mm)] - From Kit Figure 1. 3" Extension Kit MCM 6" EXHAUST HOSE EXTENSION KIT 32-59077A1 a - Original Exhaust Elbow or Exhaust Tube b - Original Clamps c - Original Exhaust Bellows - MCM 898/228/260 (With End Exhaust Outlet in Manifold) Only: If Engine Is Equipped With Closed Cooling Water Distribution Blocks. Exhaust Bellows [72408. 6-7/64" (155mm)] Must Be Used d - Original Exhaust Pipe e - Clamps - From Kit f - Exhaust Hcse [4" (102mm)j - From Kit g - Exhaust Tube [5-13/16" (148mm)] - From Kit Figure 2. 6" Extension Kit 5C-20 - EXHAUST SYSTEM Component Replacement a - Screw and Nut (4) b - Support Member c - Water Shutter d - Gasket e - Exhaust Flange f - Screws, Washers and Nuts (3) g - Clamp h - Cover ("Flapper") Figure 2. Thru Transom Exhaust Flange AC0089 MIE 228/230/255/260 SINGLE EXHAUST KIT 48640A2 IMPORTANT: Because of high back-pressure, DO NOT use this kit with 454 CID (7.4 Itr) engines. a - Hose - Cut to Fit b - Hose - 4" (102mm) Long c - Clamps - 2 At Each Connection, Tighten Securely d - Cut 2-3/8" (60mm) From End of "Y" Pipe to Allow Use of 4" (102mm) Exhaust Hose e - Connect to Thru Transom Exhaust Hose Figure 1. Exhaust Pipes and Hose Installation 90-95693 485 EXHAUST SYSTEM - 5A-21 SECTION 6-ENGINE PART A-G.M. IN-LINE INDEX Torque SpecificationsTools/Lubricants/SealantsEngine SpecificationsGeneral Engine Identification Engine RotationBearing FailuresPiston FailuresFront/Rear Engine MountRocker Arm CoverRocker Arm/Push RodValve Adjustment Engine Not Rurning Engine Running Hydraulic Valve LiftersLocating Noisy LiftersRemovalServicingDisassemblyCleaning and InspectionReassemblyInstallation Valve Stem Oil Seal and/or Valve SpringReplacement Cylinder Head Removal Installation Cylinder Head and Valve ConditioningDisassemblyCleaningInspectionRocker Arm StudsValve Guide BoresValve SeatsValvesReassembly Oil Pan Oil Pump Crankshaft Pulley (153 CID) Torsional Damper (181-250 CID) Crankcase Front Cover Oil Seal (Front Cover) Page Page 6A-1 Flywheel and Engine Coupler 6A-22 6A-3 Oil Seal (Rear Main) 6A-23 6A-4 Main Bearings 6A-24 6A " 6 Inspection 6A-24 6A-6 Checking Clearance 6A-24 6A-6 Main Bearing Replacement 6A-25 6A-7 Connecting Rod Bearings 6A-25 6A-7 Connecting Rod and Piston Assemblies 6A-26 6A-9 Removal 6A-26 6A-10 Disassembly (Method "1") 6A-26 6A-10 Disassembly (Method "2") 6A-26 6A-10 Cleaning and Inspection 6A-27 6A-10 Connecting Rods 6A-27 6A-11 Pistons 6A-27 6A-11 Piston Pins 6A-27 6A-11 Reassembly (Method "1") 6A-27 6A-11 Reassembly (Method "2") 6A-28 6A-11 Piston Rings 6A-29 6A-12 Installation 6A-29 6A-12 Crankshaft 6A-30 6A-12 Removal 6A-30 6A-13 Cleaning and Inspection 6A-30 6A-13 Installation 6A-30 6A-13 Camshaft 6A-31 6A-14 Measuring Lobe Lift 6A-31 6A-14 Removal 6A-32 6A-14 Inspection 6A-32 6A-15 Camshaft Gear Replacement 6A-32 6A-15 Installation 6A-33 6A-15 Camshaft Bearings 6A-34 6A-15 Removal 6A-34 6A-16 Installation 6A-35 6A-16 Cylinder Block 6A-36 6A-16 Cleaning and Inspection 6A-36 6A-17 Repairs 6A-36 6A-17 Cylinder Conditioning 6A-36 6A-18 Cylinder Boring 6A-36 6A-19 Cylinder Honing 6A-36 6A-20 Piston Selection 6A-37 6A-20 Distributor Lower Bushing 6A-37 6A-21 Oil Nozzle Replacement 6A-38 6A-21 Oil Filter Bypass Valve and Replacement 6A-38 TORQUE SPECIFICATIONS Fastener Location Lbs. Ft. (N.m) Camshaft Thrust Plate 6 (8) Connecting Rod Cap (11/32-24) 33 (45) Connecting Rod Cap (3/8-24) 40 (54) Crankshaft Pulley (5/16-24) 18 (24) Crankshaft Pulley (3/8-24) 23 (31) Cylinder Head A 93 (126) Distributor Clamp 20(27) Engine Coupler/Flywheel See Figure 1 Flywheel Housing to Block 21 (28) Front Mount to Block 21 (28) Main Bearing Cap 65 (88) Manifold to Head • 23 (31) Oil Pan - Side (1/4-20) 7 (9) Oil Pan - End (5/16-18) 10 (14) Oil Pan Drain Plug 23 (31) Oil Pump Cover 6 (8) Oil Pump to Block 10 (14) Oil Pump Pickup 5 (7) Rocker Arm Cover 4 (5) Spark Plugs 15(20) Starter Motor 37(50) Thermostat Cover 20 (27) Timing Gear Cover 6(8) Water Pump to Block 15 (20) A Retorque after first 20 hours of operation. • Retorque after first start up. Figure 1. Engine Coupler/Flywheel Torque 90-95693 1-888 ENGINE-6A-1 F.ngine Coupler \\ rench.91 -35547. mav not work on the later couplers. Modify wrench as shown in Figure 2, so it will work on both earlier and later stvle couplings. a - Original 91-35547 Wrencn b - Heat and Bend as Shown c - Grind Area Shown Slightly d - Heat and Bend as Shown (This is what wrench should look like when it's done) Figure 2. Modifying Engine Coupler Wrench 6A-2 - ENGINE 90-95693 485 TOOLS/LUBRICANTS/SEALANTS MERCURY MARINE SPECIAL TOOLS 91-35547 Engine Coupler Wrench 91-24697 Piston Ring Expander 91-63209 Torch Lamb KENT-MOORE SPECIAL TOOLS Kent-Moore Special Tools can be ordered from: Kent-Moore Tools, Inc. 29784 Little Mack Roseville, Ml 48066 Phone 313-774-9500 J5892 Valve Spring Compressing J8062 Valve Spring Compressor J8056 Valve Spring Tester J8101 Valve Guide Cleaner J8814 Valve Guide Reamer (Standard) J5830-2 Valve Guide Reamer (.015" O.S.) J5802-01 Rocker Arm Stud Remover J6880 Rocker Arm Stud Installer J5715 Stud Bore Reamer (.003" O.S.) J6036 Stud Bore Reamer (.013" O.S.) J8089 Carbon Remover Brush J9510-1 Piston Support Tool J24086-100 Piston Pin Tool J3936-03 Piston Ring Groove Cleaner J8037 Piston Ring Compressor J5239 Connecting Rod Guide Tool (3/8"-24) J8087 Cylinder Bore Checker J8369 Oil Pump Suctior Pipe Installer J23042 Timing Cover Seal Aligner J8520 Cam Lobe Lift Indicator J6098-01 Camshaft Bearing Installer/ Remover Tool J9534-01 Distributor Shaft Lower Bearing Installer/Remover J6978-E Pulley Hub Puller J5590 Pulley Hub Installer J22197 Universal Vibration Dampner Installer J24420-A Universal Vibration Dampner Remover LUBRICANTS/SEALANTS 92-34227 Quicksilver Perfect Seal 92-86154A1 Quicksilver 2-4-C Multi-Lube 92-91601-1 Quicksilver RTV Sealer ENGINE SPECIFICATIONS UNIT OF MEASUREMENT in. (mm) MODEL 120 140 165 DISPLACEMENT 153 CID 181 CID 250 CID CYLINDER BORE: Diameter 3.8745-3.8775(98.412-98.489) 3.9995-4.0075 3.8745-3.8775 (101.5873-101.7905) (98.412-98.489) Ou OuOu t tt o oo f ff Roun RounRoun d dd Production .0005 (.0127) Max. Service .002 (.0508) Max. Tape TapeTapeTape r rrr Productio ProductioProductio n nn Thrust Side .0005 (.0127) Max. Relief Side .0005 (.0127) Max. Service .0005 (.0127) Max. PISTON: CLEARANCE Production .0005-.0015 (.0127-.0381) Service .0025 (.06) Max. PISTON RING: COMPRESSION Groov GroovGroovGroovGroov e eeee Productio ProductioProductio n nn Top .0012-.0027 (.0305-0686) 2nd .0012-.0032 (.0305-.0813) Clearanc ClearancClearancClearancClearanc e eeee Servic ServicServic e ee Top .001-.003 (.03-.09) 2nd .001-.004 (.03-.1) Productio ProductioProductio n nn Top .010-.020 (.254-.508) Ga GaGaGaGa p pppp 2nd .010-020 (.254-.508) Servic ServicServic e ee Top .010-.030 (.25-.75) 2nd .010-.030 (.25-.75) PISTON RING: OIL Groov GroovGroov e ee Production .000-.005 (.127) Clearanc ClearancClearanc e ee Service .000-.006 (.15) Ga GaGa p pp Production .015-.055 (.381-1.397) Service .015-065 (.4-1.65) PISTON PIN: Diameter .9270-.9273 (23.546-23.553) Clearanc ClearancClearanc e ee Production .00015-.00025 (.038-.006) Service .001 (.025) Max. Fit in Rod .0008-.0016 (.020-.041) Interference CRANKSHAFT: Mai MaiMaiMaiMaiMai n nnnnn Journa JournaJournaJournaJournaJourna l lllll Diameter All 2.2983-2.2993 (5.838-5.840) Tape TapeTape r rr Production .0002 (.005) Max. Service .001 (.025) Max. Ou OuOu t tt o oo f ff Production .0002 (.005) Max. Roun RounRoun d dd Service .001 (.025) Max. Mai MaiMai n nn Brg BrgBrg . .. Production .0003-.0029 (.008-074) Clearanc ClearancClearanc e ee Service .004 (.1) Max. (Continued on Next Page) 6A-4 -ENGINE 90-95693 485 ENGINE SPECIFICATIONS (Continued) MODEL 120 140 165 Crankshaft End Play .002-.006 (.05-. 15) Max. Crankpi CrankpiCrankpiCrankpiCrankpiCrankpi n nnnnn Diameter 1.999-2.000 (50.775-50.800) 2.099-2.100 (53.315-53.340) 1.999-2.000 (50.775-50.800) Tape TapeTape r rr Production .0003 (.0076) Max. Service .001 (.025) Max. Ou OuOu t tt o oo f ff Roun RounRoun d dd Production 0002 (.051) Max. Service .001 (.025) Max. Ro RoRo d dd Brg BrgBrg . .. Clearanc ClearancClearanc e ee Production 0007-.0027 (.018-.069) .0007-.0028 (.018-.071) .0007-.0027 (.018-069) Service .004 (.1) Max. Rod Side Clearance .009-.013 (.25-.3) CAMSHAFT: Lob LobLob e ee Lif LifLif t tt (Max. (Max.(Max. ) )) Intake .2325 (5.906) .2525 (6.414) .2297 (5.834) Exhaust .2325 (5.906) .2525 (6.414) .2297 (5.834) Jcurnal Diameter 1.8682-1.8692 (47.452-47.478) Camshaft Runout .0015 (.038) Max. CYLINDER HEAD: Gasket Surface Flatness .003" (.07) in Any 6" (152) or .007" (.15) Overall Max. VALVE SYSTEM: Lifter Hydraulic Rocker Arm Ratio 1.75 to 1 Collapsed Tappet Gap 1 Turn Down from "O" Lash Fac FacFac e ee Angl AnglAngl e ee Intake 45° Exhaust 45° Seat Angle (Int. & Exh.) 46° Seat Runout (Int. & Exh.) .002 1.051) Max. Sea SeaSea t tt Widt WidtWidt h hh Intake 1/32-1/16 (.8-1.6) | 1/32-3/32 (.8-2.4) Exhaust 1/16-3/32 (1.6-2.4) Ste SteSteSteSte m mmmm Clearanc ClearancClearancClearancClearanc e eeee Productio ProductioProductio n nn Int. .0010-.0027 (.025-.069) Exh. .0015-.0032 (.038-.081) Servic ServicServic e ee Int. .0037 (.094) Max. Exh. .0052 (.132) Max. Spring SpringSpringSpringSpringSpring s sssss Free Length 2-5/16 [2.08 (53)] 1-29/32 [1.90 (48)] Pressur PressurPressur e ee Lbs LbsLbs . .. Ft FtFt . .. Closed 78-86 (106-116 N.m) at 1-21/32 [1.66 (42.2)] 83 (113 N.m) at 1-21/32 [1.66 (42.2)] 54-64 (73-86 N.m) at 1-21/32 [1.66 (42.2)] Open 170-180 (230-244 N.m) at 1-17/64 [1.26 (32)] 175 (237 N.m) at 1-17/54 [1.26 (32)] 180-192 (244-260 N.m) at 1-17/64 [1.27 (32.3)] Installe InstalleInstalle d dd Heigh HeighHeigh t tt ±1/32 ±1/32±1/32 " "" (.8 (.8(.8 ) )) Intake 1-21/32 [1.6562 (42.07)] Exhaust 1-21/32 [1.6562 (42.07)] Dampe DampeDampe r rr Free Length 1-15/16 [1.94 (49.2)] Approx. No. of Coils 4 90-956931-888 ENGINE-6A-5 GENERAL Some Repairs, Listed in This Section, Must Be Completed with Engine Removed from Itoat. Engine Removal Depends I pon Type of Repair and Boat Design. Place Engine on Engine Stand for Major Repairs. In-line engines with 153. 181. and 250 cu. in. displacements are covered in this section. Full pressure lubrication thru a full flow oil filter is furnished by a gear-type oil pump. Distributor, driven by a helical gear on camshaft, drives oil pump. Main oil gallery feeds oil thru drilled passages to camshaft and crankshaft to lubricate bearings. Main oil gallerv also feeds valve lifters which, thru push rods, feed individuallv-mounted rocker arms. Cubic inch displacement (CID) of each MerCruiser model is listed below . ENGINE IDENTIFICATION The MerCruiser Model can be determined by looking at the LAST TWO LETTERS of the engine code stamped into the cylinder block. (Figure 1) This code number is stamped on all MerCruiser Power Packages and replacement partial engines but not replacement cylinder block assemblies. If the engine serial number, and/or model decals are missing, the engine code letters may help in determining the engine model. Following is a list of C.M. engines and their respective code letters. a - 4 and 6 Cylinder-ln-Line (Near Distributor) Figure 2. G.M. Engine Code Location MCM Stern Drive Engines (All Are LH Rotation) 120-NB 165-SD 140-RA ENGINE ROTATION a - Engine Code (V06172WT) b - Last Two Letters (WT) Figure 1. G.M. Engine Code (V-8 Shown) 6A-6 - ENGINE All Engines Are Left Hand Rotation When Viewed from Flywheel End 90-95693 485 Bearing Failures Piston Failures PRE-IGNITION Pre-ignition is abnormal fuel ignition, caused bv combustion chamber hot spots. Control of the start of ignition is lost, as Figure 1. Pre-lgnition Damage combustion pressure rises too early, causing power loss and rough running. The upward motion of the piston is opposed by the pressure rise. This can result in extensive damage to the internal parts from the high increase in combustion chamber temperature. (Figure 1) Pre-lgnition Causes 1. Hot spots in the combustion chamber from glowing deposits (due in turn to the use of improper oils and/or fuels). 2. Overheated spark plug electrodes (improper heat range or defective plug). 3. Any other protuberance in the combustion chamber, such as an overhanging piece of gasket, an improperlv seated valve or any other inadequately cooled section of material which can serve as a source. 90-95693 1-888 ENGINE-6A-7 DETONATION Detonation, commonly called "fuel knock", "spark knock" or "carbon knock", is abnormal combustion of the fuel which causes the fuel to explode violently. The explosion, in turn, causes overheating or damage to the spark plugs, pistons, valves and, in severe cases, results in pre-ignition. (figure 2) Use of low octane gasoline is one of the most common causes of detonation. Even with high octane gasoline, detonation could occur if engine maintenance is neglected. Other Causes of Detonation IMPORTANT: Use of improper fuels will cause engine damage and poor performance. 1. Over-advanced ignition timing. 2. Lean fuel mixture at or near full throttle (could be caused by carburetor or leaking intake manifold). 3. Cross-firing spark plugs. 4. Excess accumulation of deposits on piston and/or combustion chamber (results in higher compression ratio). 5. Inadequate cooling of engine by deterioration of cooling system. Engine failures, which result from the foregoing conditions, are beyond the control of Mercury Marine, therefore, no warranty will apply to failures which occur under these conditions. Figure 2. Detonation Damage 6A-8 - ENGINE 90-95693 485 Out with Press Out with Press FRONT/REAR ENGINE MOUNT M COO 34 Front Engine Mount Press Mount a. Gasket used on 120R/140R Engines Only MC0028 Rear Engine Mount/Flywheel Housing 90-95693 485 ENGINE-6A-9 ROCKER ARM COVER REMOVAL 1. Disconnect crankcase ventilation hose at rocker arm cover. 2. Disconnect and remove fuel line. 3. Remove attaching bolts. 4. Remove rocker arm cover and gasket. INSTALLATION 1. Clean gasket surfaces on cylinder head and rocker arm cover. 2. I. sing a new gasket, install rocker arm cover and torque to specifications. AOTE: U'iring harness and inlet hose clips must be installed under their proper screws. 3. Connect crankcase ventilation hoses. 4. Replace fuel line. Tighten connections securely and check for leaks. Figure 1. Valve Mechanism REMOVAL I. Remove rocker arm cover as outlined. ROCKER ARM/PUSH ROD 2. Remove rocker arm nuts, rocker arm balls, rocker arms and push rods. MOTE: Place rocker arms, rocker arm balls and push rods in a rack so that thev may be reinstalled in same location. INSTALLATION A OTE: Whenever new rocker arms and/or rocker arm balls are being installed, coat bearing surfaces of rocker arms and rocker arm balls with engine oil. 1. Install push rods. Be sure that push rods seat in lifter socket. 2. Install rocker arms, ball units and rocker arm nuts. 3. Adjust valves. 4. Install rocker arm cover. 5. Adjust carburetor idle speed and mixture. VALVE ADJUSTMENT ENGINE NOT RUNNING Remove valve cover. Adjust valves when lifter is on low lobe of camshaft, as follows: a. Mark distributor housing w ith chalk at No. I and No. 4 cylinder spark plug wire location for 4-cvlinder engine (No. I and No. 6 for 6-cylinder engine). Disconnect plug wires at spark plugs and coil and remove distributor cap and plug wire assembly. MOTE: I aires arc numbered as follows (starting from front of engine): Mo. I Exhaust Vo. 4 • Intake Mo. I Intake Mo. 4 Exhausl Mo. 2 Intake Xo. 5 Exhaust Mo. 2 Exhaust A o. 5 Intake 6-Cyl. Mo. 3 Exhaust \o. 6 • Intake Mo. 3 Intake \o. 6 -Exhaust b. Crank engine until distributor rotor points lo No. 1 cvlinder position and breaker points are open. Following valves can be adjusted with engine in No. 1 firing position. No. 1 Cvlinder - Exhaust and Intake No. 2 Cylinder - Intake No. 3 Cylinder - Exhausl No. 4 Cylinder - Intake No. 5 Cylinder - Exhaust (6-Cyl.) c. Back out adjusting nut until lash is felt at push rod. then :urn in adjusting nut until all lash is removed. This can be determined by checking push rod end play (up and down) while turning adjusting nut. (Figure 2) U hen plav is removed, turn adjusting nut in 1 additional turn. d. Crank engine until distributor rotor points to No. 4 position for 4-cvlinder engine (No. 6 for 6-cylinder engine) and breaker points are open. Following valves can be adjusted with engine in this position: No. 2 Cylinder - Exhaust No. 3 Cvlinder - Intake No. 4 Cvlinder - Exhaust No. 5 Cylinder - Intake (6-Cvl.) No. 6 Cylinder - Intake and Exhaust (6 Cyl.) Install distributor cap. spark plug wires and coil lead. Install rocker arm cover. 6A-10 - ENGINE 90-95693 485 01590 Figure 2. Valve Adjustment HYDRAULIC Refer to Figure 3 for parts identification. Hydraulic valve lifters seldom require attention. Lifters are simple in design, readjustments are not necessary and lifter servicing requires only that care and cleanliness be exercised in handling of parts. LOCATING NOISY LIFTERS L se a piece of garden hose approximately 4 ft. (1.2 m) in length to locate a noisy valve lifter. Place one end of hose near end of each intake and exhaust valve, with other end of hose to the ear. Sound, thus, is localized, making it easy to determine which lifter is at fault. Another method is to place a finger on face of valve spring retainer. If lifter is not functioning properly. a distinct shock will be felt when valve returns to its seat. General tvpes of valve lifter noise are: 1. Hard Rapping Noise - Usuall v caused bv plunger becoming tight in bore of lifter body to such an extent that return spring can no longer push plunger back up to working position. Probable causes are a. Excessive varnish or carbon deposit which causes abnormal stickiness. b. Galling or "pickup" between plunger and bore of lifter body, usually caused by an abrasive piece of dirt or metal wedging between plunger and lifter body. 2. Moderate Rapping Noise - Probable causes are a. Excessively high leakdown rate. b. Leaky check valve seat. c. Improper adjustment. 3. General Noise Throughout Valve Train - This, in most cases, will bea definite indication of insufficient oil supply or improper adjustment. 4. Intermittent Clicking - Probable causes are a. A microscopic piece of dirt momentarily caught between ball seat and check valve ball. 90-95693 1-888 ENGINE RUNNING Following procedure should be completed only if readjustment is required. 1. Run engine until it reaches normal operating temperature, then remove valve cover. 2. With engine running at idle, back off valve rocker arm nut until valve rocker arm starts to clatter. (Figure 2) 3. Turn rocker arm nut down slowly until clatter just stops. This is zero lash position. 4. Turn nut down V\ additional turn and pause 10 seconds until engine runs smoothly. Repeat additional V* turns, pausing 10 seconds each time, until nut has been turned down 1 turn from zero lash position. NOTE: This 1 turn pre-load adjustment must be done slowly to allow lifter to adjust itself, thus preventing possible interference between inlet valve head and top of piston which might result in internal damage and/or bend push rods. 5. Repeat Steps 2-3-4 to adjust other valves. 6. Install valve cover, using new gasket. 7. Adjust carburetor. VE LIFTERS b. In rare cases, ball itself may be out-of-round or have a flat spot. c. Improper adjustment. In most cases, where noise exists in one or more lifters, all lifter units should be removed, disassembled, cleaned in a solvent, reassembled and reinstalled in engine. If dirt, varnish, carbon, etc, are shown to exist in one unit, it likely exists in all units. Thus, it would be only a matter of time before all lifters cause trouble. REMOVAL 1. Remove rocker arm and push rod. 2. Mark distributor housing with chalk at each cylinder position (plug wire), then disconnect plug wires at spark plugs and coil and remove distributor cap and plug wire assembly. 3. Crank engine until distributor rotor points to No. 1 position, then disconnect distributor primary lead at coil and remove distributor. 4. Remove push rod covers (discard gaskets). 5. Remove valve lifters. NOTE: Place valve lifters in a rack so they may be reinstalled in same location. SERVICING Two types of hydraulic lifters are used. Both types operate on same principle and are serviced basically in same manner. Complete lifter assemblies are interchangeable, but parts from one lifterare not interchangeable with another. Both liftersare easily identified by outside configuration of lifter body. Identify them as lifter "A " and lifter "B". (Figure 3) ENGINE-6A-11 DISASSEMBLY 1. Hold plunger down with push rod arid remove push rod seat retainer with blade of small screwdriver. 2. Remove push rod seat and metering valve lifter A (or push rod seat and inertia valve assembly lifter "B i. (Figure 3) 3. Remove plunger, ball check valve assembly and plunger spring. 4. Remove ball check valve and spring by prying ball retainer loose from plunger with blade of small screwdriver. (Figure 4) CLEANING and INSPECTION Thoroughlv clean all parts in cleaning solvent and inspect parts carcfullv. If any parts are damaged or worn, entire lif ter assembly should be replaced. If outside of lifter body is scuffed or worn, inspect cvlinder block lifter bore. If bottom of lifter is scuffed or worn, inspect camshaft lobe. If push rod seat is scuffed or worn, inspect push rod. NOTE: Do not remove inertia valve and retainer (lifter "Ft") (Figure 3 J from push rod seat. To check valve, shake push rod seat and inertia valve assembly. I alt e should move. REASSEMBLY 1. Place check ball on small hole in bottom of plunger. 2. Insert check ball spring on seat in ball retainer and place retainer over ball so that spring rests on ball. (Carefully press retainer into position in plunger with blade of a small screwdriver. (Figure 5) 3. Place plunger spring over ball retainer and slide lifter bodv over spring and plunger, being careful that oil feed holes in lifter body and plunger line up. 4. Fill assembly with oil. then insert end of a W (3mm) drift pin into plunger and press down stronglv. At this point, oil holes in lifter bod\ and plunger assemblx will be aligned. (Figure 6) 5. Insert a 1/16" (1.5rtim) drift pin thru both oil holes to hold plunger down against lifter spring tension. (Figure 6) NOTE: On lifter "B" (Figure 3), drift pin must noi extend inside plunger. 6. Remove W drift pin and refill assemblv with oil. 7. Install metering valve and push rod seat lifter "A " (or push rod seat and inertia valve assembly lifter "B"). (Figure 3) 1 - Lifter Body 5 - Check Ball Retainer 2 - Push Rod Seat 6 - Push Rod Seat Retainer 3- Metering Valve (Lifter "A") 7 - Plunger Inertia Valve (Lifter "B") 8 - Check Ball Spring 4 - Check Ball 9 - Plunger Spring Figure 3. Hydraulic Valve Lifters 8. Install push rod seal retainer, press down on push rod seat and remove 1/16" drift pin from oil holes. Lifter now is completely assembled, filled with oil and ready for installation. NOTE: Before installing a new lifter, coat bottom oj lifter with engine oil. 6A-12 - ENGINE 90-95693 485 Figure 5. Installing Ball Check Valve 05060 Figure 4. Removing Ball Check Valve Figure 6. Assembling Hydraulic Lifters INSTALLATION 1. Install valve lifters. NOTE: Whenever valve lifters are being installed, coat bottom of valve lifters with engine oil. 2. Install push rod covers, using new gaskets, and torque to specifications. 3. Install distributor, positioning rotor to No. 1 cylinder position, then connect primarv lead at coil. 4. Install distributor cap and high tension wires. 05022 5. Install and adjust valves. 6. Adjust ignition timing, carburetor idle speed and mixture. VALVE STEM OIL SEAL and/or VALVE SPRING REPLACEMENT 1. Remove rocker arm cover. 2. Remove spark plug, rocker arm and push rod on cvlirider to be serviced. 3. Place piston for that cvlirider at TIM! to prevent valves from dropping into combustion chamber. NOTE: J. tool to apply air to cylinder is available thru local jobbers. Engines use tapered spark plugs. 4. Compress valve spring with Tool .1-5892 and remove valve keys, valve spring cap, spring shield and valve spring. (Figure 8) 5. Remove valve stem oil seal. Figure 7. Valve Spring and Related Parts 05027 90-95693 1-888 ENGINE-6A-13 6. To install, set valve spring (close, coiled end of spring is installed against cylinder head), valve shield and valve cap in place. Compress spring with Tool J-5892 and install oil seal in lower groove of stem, making sure that seal is flat and not twisted. MOTE: A light coat of oil on seal will help prevent twisting when compressor tool is released.. Install valve keys and release compressor tool. Be sure that keys seat properly in upper groove of valve stem. MOTE: Grease may be used to hold keys in place while releasing compressor tool. 8. Install spark plug and torque to specifications. 9. Repeat Steps 2 thru 8 for other cylinders. 10. Install and adjust valve mechanism. Figure 8. Compressing Valve Spring CYLINDER HEAD Figure 1. Cylinder Head Torque Sequence REMOVAL 1. Drain water from cylinder block and manifold. 2. Disconnect fuel line support clamps and remove fuel line. 3. Remove exhaust manifold. 4. Disconnect cooling hoses. 5. Disconnect wire from temperature sending unit (located in water distribution housing) and remove water distribution housing from cylinder head. 6. Disconnect wires from coil and remove coil. 7. Remove circuit breaker bracket and lifting eye. 8. Disconnect spark plug leads from spark plugs and remove all spark plugs from cylinder head. 9. Remove rocker arm cover and valve mechanism. 10. Remove cylinder head bolts, cylinder head and gasket. Handle cylinder head carefully to prevent damage. INSTALLATION Gasket surfaces on both head and block must be clean of any foreign matter and free of nicks and/or deep scratches. Cylinder bolt threads in block, and threads on cylinder head bolt must be cleaned. Dirt will affect bolt torque. DO NOT use gasket sealer on composition steel asbestos gaskets. 1. 1'lace new gasket in position over dowel pins. CAUTION DO NOT use steel automotive type cylinder head gaskets. Use only Quicksilver replacement parts. 2. Carefullv guide cvlinder head into place over dowel pins and gasket. 3. Coat threads of cylinder head bolts with Perfect Seal and install finger-tight. 4. Tighten cylinder head bolts a little at a time in sequence shown on torque sequence chart (Figure 1) until specified torque is reached. IMPORTANT: Be sure to retorque cylinder head while performing 20-hour checkup. Failure to re- torque could result in poor engine performance, blown cylinder head gaskets, burned valves, warped cylinder head or all four. 5. Install valve mechanism and rocker arm cover. 0. Install spark plugs and spark plug leads lo proper plugs. 7. Install lifting eye and circuit breaker bracket. 8. Install coil and coil leads. 9. Install water distribution housing to cylinder head and connect temperature sending unit lead. 10. Connect cooling hoses to water distribution housing. 11. Install exhaust manifold. 12. Install fuel line and fuel line support clamps. 6A-14 - ENGINE 90-95693 485 CYLINDER HEAD and VALVE CONDITIONING DISASSEMBLY 1. Remove cylinder head. 2. Compress the valve springs with Tool J-8062 (Figure 2) and remove valve keys. Release compressor tool and remove spring caps, spring shields and valve springs. Remove oil seals from valves. 3. Remove valves from cylinder head and place them in a rack in their proper sequence for later assembly in their original positions. CLEANING 1. Clean all carbon from combustion chambers and valve ports with Tool J-8089. (Figure 3) 2. Thoroughly clean valve guides with Tool J-8101. (Figure 4) 3. Clean all sludge from push rods, rocker arms and push rod guides. 4. Clean valve stems and valve heads on a buffing wheel. 5. Clean cylinder head gasket mating surface. Figure 2. Compressing Valve Spring Figure 4. Cleaning Valve Guides INSPECTION 1. Inspect cylinder head gasket surface for flatness. If not within specifications, resurface or replace cylinder head. 2. I nspect cylinder head for cracks in exhaust ports, combustion chambers or external cracks to water chamber. 3. Inspect valves for burned heads, cracked faces or damaged stems. IMPORTANT: Excessive valve stem to bore clearance will cause excessive oil consumption and may cause valve breakage. Insufficient clearance will result in noisy and sticky valves and disturb smooth engine operation. Torque Wrench Figure 3. Cleaning Combustion Chambers Figure 5. Checking Valve Spring Tension 90-95693 485 ENGINE - 6A-15 4. Measure valve stem clearance as follows: Clamp a dial indicator on one side of cylinder head rocker arm cover gasket rail, locating indicator so that movement of valve stem from side-to-side (crosswise to head) will cause a direct movement of indicator stem. Indicator stem must contact side of valve stem just above valve guide. W ith valve head dropped about 1/16" (1.5mm) off valve seat, move stem of valve from side-to-side, using light pressure to obtain a clearance reading. If clearance exceeds specifications, it will be necessary to ream valve guides for oversize valves as outlined. 5. Check valve spring tension with Tool J-8056 spring tester. (Figure 5) Replace if not within 10 lbs. of specified load (without dampers). 6. Inspect rocker arm studs for wear or damage. ROCKER ARM STUDS Rocker arm studs with damaged threads or with loose fit in cylinder heads should be replaced with new. oversize studs. Studs mav be installed after reaming holes as follows: 1. Drain water from cylinder block. Remove old stud by placing Tool J-5802-01 over stud, installing nut and flat washer and removing stud by turning nut. (Figure 6) 3. Ream hole for oversize stud with Tool J-5715 for .003" oversize or Tool J-6036 for .013" oversize. (Figure 7) IMPORTANT: Do not attempt to install an oversize stud without reaming stud hole. 4. Coat press-fit area of stud with Perfect Seal. Install new stud, using Tool J-6880 as a guide. Gauge should bottom on head. (Figure 8) 01597 Figure 6. Removing Figure 7. Reaming Rocker Arm Stud Rocker Arm Stud Bore Figure 10. Measuring Valve Seat Concentricity VALVE GUIDE BORES \alves with oversize stems are available (see specifications). To ream valve guide bores lor .015" oversize valves, use Tool J-5830-2 and for standard, use Tool J-8814. (Figure 9) 01598 01595 Figure 8. Installing Figure 9. Reaming Rocker Arm Stud Valve Guide VALVE SEATS 1. \ alves must seat perfect for the engine to deliver the power and performance built into it. 2. Good contact between each valve and its seal in head is a must to ensure that heat in valve head will be properh carried away (cooled). 3. Recommendations of equipment manufacturer for reseating valve seats should be careful 1 v followed to attain proper results. Regardless o( what Ivpe of equipment is used, however, it is essential that valve guide bores be free from carbon or dirt. 4. After grinding valve seat, check seal (or out-of-round. (Figure 10) (Max. is .002" (.05mm) out-ol-round with total indicator reading.) 05024 6A-16 - ENGINE 90-95693 485 VALVES 2. ( sing compressor tool, assemble valve spring and related parts as outlined in "Valve Stern Oil Seal and/or Valve Pitted valves can be refaced to proper angle (f igure 11) thus Spring". (Steps 6 and 7) ensuring correct relation between head and stem on valve 3. Install remaining valves. refacing mechanism. Valve stems, which show excessive wear 4. Check each vale stem oil seal by placing a vacuum cup or or valves that are warped excessively, should be replaced. similar device over end of valve stem and against cap. When a valve head (warped excessively) is refaced. a knife Operate vacuum cup and make sure thai no air leaks past edge will be ground on part or all of valve head due to amount seal. of metal that must be removed to completely reface. Knife D. Check installed height of valve springs with scale. (Figure edges lead to breakage, burning or pre-ignition from heat 13) Measure from top of spring seat to top of valve spring localizing on this kn:fe edge. If edge of valve head is less than shield. If this exceeds specified height, install a valve 1/32" (.8mm) thickness after grinding, replace valve. spring seat shim approximately 1/16" (1.5mm) thick. At no time should spring be shimmed to give an installed Recommendations of equipment manufacturer for refacing height under minimum specified. valves should be carefullv followed to obtain best results. IMPORTANT: Only extreme end of valve stem is hardened to resist wear. Do not grind end of stem excessively. 1. After cleaning valve face and cylinder head valve seat of grinding particles, make pencil marks about Vt" (6mm) apart across valve face, place valve in cvlinder head and give valve Vi-turn in each direction while exerting firm pressure on head of valve. 2. Remove valve and check face carefully. If all pencil marks have not been removed at point of contact with valve seat, it will be necessarv to repeat refacing operation and again recheck for proper seating. 3. Grind and check remaining valves in same manner. Figure 12. Valve Spring Installation INTERFERENCE Intake Valves - All Engines Exhaust Valves - All Engines Figure 11. Relation of Valve and Seat Angles REASSEMBLY 1. Insert valve in proper port. * " 01603 Figure 13. Checking Valve Spring Installed Height 90-95693 1-888 ENGINE-6A-17 OIL PAN REMOVAL 1. Disconnect battery. NOTE: Removal of engine from boat may be required. 2. Drain engine oil. 3. Remove starter motor. 4. Remove oil pan screws, oil pan. side and end gaskets. INSTALLATION 1. Thoroughly clean all gasket sealing surfaces. 2. Refer to Figure 14 for installation. 3. Install oil pan. 4. Install starter motor. 5. Fill crankcase with oil. 6. Connect batterv. (A) 153, 181 and early 250 CID Engines (C) 250 CID Engine 16 Holes - RTV MUST BE USED on Front and Side Rails Shallow or No Groove - RTV Rear Main MUST BE USED (B) or (C) Bearing Cap Deep Machined Groove Rear Pan Seal MUST BE USED (A) (B) 250 CID Engine 24 Holes - Gasket or RTV Sealer CAN BE USED on Front and Side Rails Figure 14. Oil Pan 90-95693 485 6A-18 - ENGINE OIL PUMP Oil pump consisls of 2 gears and a pressure regulator valve enclosed in a 2-piece housing. Oil pump is driven by distributor shaft which is driven by a helical gear on camshaft. A baffle is incorporated on pickup screen to eliminate pressure loss. Lse Figure 15 for reference. REMOVAL 1. Remove oil pan. 2. Remove flange mounting bolts and pickup pipe bolt, then remove pump and screen as an assemblv. DISASSEMBLY IMPORTANT: DO NOT remove pickup screen and pipe assembly unless replacement is necessary. Loss of press fit condition could result in air leak and loss of oil pressure. 1. Remove pump cover attaching screws, pump cover and pump cover gasket. IMPORTANT: Mark gear teeth so they may be reassembled with same teeth indexing. 2. Remove idler gear and drive gear and shaft from pump bodv. 3. Remove pressure regulator valve retaining pin. pressure regulator, spring and valve. 4. If pickup screen and pipe assembly need replacing, mount pump in a soft-jawed vise and extract pipe from pump. IMPORTANT: Do not disturb pickup screen on pipe which is serviced as an assembly. CLEANING and INSPECTION 1. Wash all parts in cleaning solvent and drv with compressed air. 2. Inspect pump body and cover for cracks or excessive wear. 3. Inspect pump gears for damage or excessive wear. 4. Check drive gear shaft for looseness in pump body. 5. Inspect inside of pump cover for wear that would permit oil to leak past ends of gears. 6. Inspect pickup screen and pipe assembly for damage to screen, pipe or relief grommet. 7. Check pressure regulator valve for fit. NOTE: Pump gears and body are not serviced separately. If pump gears or body are damaged or worn, replace entire oil pump assembly. REASSEMBLY I. If pickup screen and pipe assembly was removed, replace with a new part. Loss of press fit condition could result in air leak and loss of oil pressure. Mount pump in soft -jawed vise and apply Perfect Seal to end of pipe with Tool J-8369. Tap pipe in place with plastic hammer. 2. Install pressure regulator valve spring and retaining pin. 3. Install drive gear and shaft in pump bodv. 4. Install idler gear in pump body with smooth side of gear toward pump cover opening, aligning teeth marked in disassembly. 5. Install pump cover with new gasket and torque attaching screws lo specifications. 6. Turn drive shaft In hand lo check for smooth operation. 1 - Pressure Regulator Valve 6 - Cover Gasket 2 - Pressure Regulator Spring 7 - Idler Gear 3 - Retaining Pin 8 - Drive Gear and Shaft 4 - Screws 9 - Pump Body 5 - Pump Cover 10 - Pickup Screen and Pipe Figure 15. Oil Pump INSTALLATION 1. Align oil pump drive shafts lo match with distributor tang, then install oil pump to block, positicning flange over distributor lower bushing. L'se no gaskel. IMPORTANT: Oil pump should slide easily into place. If not, remove and reposition slot to align with distributor tang. 2. Install oil pump bolts and tighten securelv. 3. Install oil pan. 90-95693 1-888 ENGINE-6A-19 CRANKSHAFT PULLEY (153 CID) REMOVAL Using Too! J-5590, strike hub until it bottoms against crankshaft gear. 1. Support front of engine (if in boat) with overhead hoist. 2. Remove front mounting bracket and drive bell Remove IMPORTANT: Crankshaft extends slightly thru hub, crankshaft pulley from pulley hub. and a tool is necessary to drive hub completely into 3. Install puller Tool J-6978-E to pulley hub and remove hub. bottomed position. (Figure 1) Remove puller tool. 2. Install pulley onto hub. \ OTE: There are two W holes and one .:>/' 16" hole that must he matched on huh in order to properly position timing mark. (Figure 2) 3. Install drive belt and adjust tension. 4. Install front mounting bracket. 5/16" Bolt 01608 Figure 1. Removing Crankshaft Pulley Hub INSTALLATION 3/8" Bolts l. Coat oil seal lip with engine oil. position hub over crankshaft and key arid start hub into position with a mallet. Figure 2. Install Pulley to Hub TORSIONAL DAMPER (181/250 CID) REMOVAL 1. Support front of engine (if in boat) with overhead hoist. 2. Remove front mounting bracket and drive belt. (Remove retaining bolt, if so equipped.) 3. Install Tool J-6978-E to balancer and turn puller screw to remove damper. (Figure 3) Remove tool from damper. Inertia weight section of torsional damper is assembled to hub with rubber type material. Installation procedures (with proper tool) must be followed or movement of inertia weight section on hub will upset tuning of torsional damper. INSTALLATION 1. Coat front cover oil seal lip with engine oil. Figure 3. Removing Harmonic Balancer 6A-20 - ENGINE 90-95693 485 2. Attach damper installer Tool J-22197 to damper as shown in Figure 4. 3. Position damper on crankshaft and drive into position until it bottoms against crankshaft gear. 4. Remove installation tool. 5. Install drive belt and adjust tension. 6. Install front mounting bracket. CRANKCASE FRONT COVER REMOVAL 1. Remove oil pan. 2. Remove crankshaft pulle\ and hub or damper. 3. Remove crankshaft front cover attaching screws, cover and gasket. INSTALLATION 1. Clean gasket surfaces on block and crankcase front cover. 2. Install centering Tool J-23042 in crankcase front cover seal. (Figure 5) 3. Coat gasket with gasket scaler and place in position on cover, then install crankcase front cover to block and torque to specifications. 4. Remove centering tool. IMPORTANT: Use only centering tool to align crankcase front cover so that crankshaft hub or OIL SEAL (FRONT COVER) Figure 5. Centering Tool (J-23042) In Cover damper installation will not damage seal and to position seal to seal evenly around damper or hub surface. 5. Install crankshaft hub and/or damper. 6. Install oi pan. Figure 4. Installing Harmonic Balancer REPLACEMENT With Cover Removed 1. ith cover removed, prv old >eal out of cover from front with large screwdriver. 2. Install new seal .-o that lip of seal is toward inside of engine and drive seal into position with Tool J-23042. (Figure 6) IMPORTANT: Support cover at sealing area. Without Cover Removed 1. With crankshaft pulley and hub or damper removed, pry old seal out of cover from front with large screwdriver, being careful not to damage seal surface on crankshaft. 2. Install new seal so that lip of seal is toward inside of engine and drive seal into position with Tool J-23042. (Figure 7) 90-95693 485 ENGINE - 6A-21 01685 05031 01685 05031 Figure 6. Installing Oil Seal (Cover Removed) Figure 7. Installing Oil Seal (Cover Installed) FLYWHEEL and ENGINE COUPLER REMOVAL 1. Remove engine from boat. 2. Remove bell housing. 3. Remove coupler by removing retaining nuts and washers. 4. Remove flywheel. INSPECTION 1. Check engine coupling assembly. 2. Check flywheel ring gear for worn or missing teeth. INSTALLATION 1. Install flywheel. Line up dowel hole in flywheel with dowel hole in crankshaft flangeand set flywheel in place on studs. (Figure 8) 2. Place drive coupling on studs and install washers and lock nuts. Torque nuts to specifications with Torque Wrench and Adaptor (91-35547). Figure 8. Flywheel Position on Crankshaft Flange 3. Install bell housing. 4. Lubricate coupler splines with 2-4-C MuIti-Lube and install engine in boat. 5. Check engine alignment. _ 01655 90-95693 485 6A-22 - ENGINE OIL SEAL (REAR MAIN) REPLACEMENT Rear main bearing oil seal can be replaced (both halves) without removing crankshaft. IMPORTANT: Always replace upper and lower seal as a unit. Install with lip facing toward inside of engine. Where seal has 2 lips, install lip with helix toward front of engine. 1. With oil pan removed, remove rear main bearing cap. 2. Remove oil seal from rear main bearing cap bv prving from bottom with small screwdriver. Figure 9. Removing Oil Seal (Upper Half) Typical 3. Lubricate lip of new seal with engine oil. Keep oil off parting line surface, as this is treated with glue. Insert seal in cap and roll seal into place with finger and thumb, using light pressure so seal tangs at parting line do not cut bead on back of seal. IMPORTANT: Later seals come with an installation tool. Follow instructions supplied with new seal. 4. To remove upper half of seal, use small hammer and tap brass pin punch on one end of seal until it protrudes far enough to be removed with pliers. (Figure 9) IMPORTANT: Always wipe crankshaft surface clean before installing new seal. Figure 10. Sealing Bearing Cap and Block 5. Lubricate lip of new seal with engine oil. Keep oil off partingline surface. Gradually push with a hammer handle (while turning crankshaft) until seal is rolled into place (similar to installing a main bearing). Re careful that seal tangs at parting line do not cu! bead on back of seal. I se sealer at parting line on rear main bearing cap half of seal. 6. Appiv Perfect Seal to cvlinder block in seal area. (Figure 10) 7. Install rear main bearing cap (with new seal) and torque to specifications. 8. Install oil pan. 90-95693 485 ENGINE-6A-23 MAIN BEARINGS 1. Main bearings are precision insert tvpe and do not utilize shim for adjustment. If clearances are found to be excessive. a new bearing (both upper and lower halves) will be required. Bearings are available in standard size and undersize. 2. Selective fitting of both rod and main bearing inserts is necessary in production to obtain close tolerances. For example, one half of a standard insert with one half of a .001" undersize insert mav be found, which will decrease clearance .0005" from using a full standard bearing. 3. ^ hen a production crankshaft cannot be precision fitted by this method, it then is ground .009" undersize on main journals only. A .009" undersize bearing and .010" under- size bearing may be used for precision fitting in same manner as previously described. Anv engine, fitted with a .009" undersize crankshaft, will be identified bv following markings. • '.009' will be stamped on crankshaft counterweight forward of cefttermain journal. • No. "9" will be stamped on block at left front oil pan rail. INSPECTION In general (except No. 1 bearing), lower half of bearing shows greater wear and most distress from fatigue. If. upon inspection. lower half is acceptable, it can be assumed that upper half also is satisfactory. II lower half shows evidence of wear or damage, replace both upper and lower halves. Never replace one half without replacing other half. Typical bearing failures are shown under General . CHECKING CLEARANCE To obtain most accurate results, use Plastigage (or its equivalent), a wax-like plastic material which will compress evenlv bet ween bearing and journal surfaces without damaging either surface. itb engine upside down, crankshaft will rest on upper bearings, and total clearance can be measured between lower bearing and journal. IMPORTANT: To assure proper seating of crankshaft, torque all bearing cap bolts as specified. In addition, before checking fit of bearings, wipe surface of crankshaft journal and face and back of bearing clean of oil. 1. Starting with rear main bearing, remove bearing cap and wipe oil from journal and bearing cap. 2. Place piece of gauging plastic the full width of bearing (parallel to crankshaft) on journal. (Figure 1) IMPORTANT: Do not rotate crankshaft while the gauging plastic is between bearing and journal. Figure 1. Gauging Plastic on Journal 3. Install bearing cap and evenlv torque retaining bolt- to specifical ions. 4. Remove bearing cap. 5. A graduated scale (correlated in thousandths of an inch) exists on edge of gauging plastic envelope. \\ it bout removing gauging plastic, measure its compressed width lat widest point) with graduations on gauging plastic envelope. (Figure 2) IMPORTANT: Normally, main bearing journals wear evenly and are not out-of-round. However, if a bearing is being fitted to an out-of-round journal (.001" [.025mm] max.), be sure to fit to maximum diameter Figure 2. Measuring Gauging Plastic 6A-24 - ENGINE 90-95693 485 of journal. If bearing is fitted to minimum diameter, 8. Proceed to next bearing, \fter all bearings have been and journal is out-of-round .001", interference be-checked, rotate crankshaft so that no excessive drag exists. tween bearing and journal will result in rapid bear-9. Measure crankshaft end play as outlined under "Cranking failure. If flattened gauging plastic tapers to-shaft". ward middle or ends, there is a difference in 10. Install new rear main bearing oil seal; n cvlinder block arid clearance indicating taper, low spot or other irregu-main bearing cap. larity of bearing or journal. Be sure to measure journal with a micrometer if flattened gauging plastic indicates more than .001" difference. MAIN BEARING REPLACEMENT 6. If bearing clearance is within specifications, bearing insert 1. Remove and inspect crankshaft. is satisfactory. If clearance is not within specifications, 2. Remove main bearings from cylinder block and main bear- replace insert, \lwavs replace both upper and lower insert ing caps. as a unit. 3. Coat bearing surfaces of new. correct-size, main bearings 7. A standard .001" or .002" undersize bearing mav produce with oil and install in cylinder blockand main bearing caps. proper clearance. If no!. regrind crankshaft journal for use Check clearance. with next undersize bearing. 4. Install crankshaft. CONNECTING ROD BEARINGS Connecting rod bearings are precision insert tvpe and do not utilize shims for adjustment. DO NOT KILE RODS OR ROD CAPS. If clearances are found to be excessive, a new bearing will be required. Bearings are available in standard size and undersize. INSPECTION and REPLACEMENT 1. Remove connecting rod cap and hearing. 2. Inspect bearing for evidence of wear or damage. (Defective bearings should not be installed.) Typical bearing failures are shown under General . 3. Wipe bearings and crankpin clean of oil. 4. Measure crankpin for out-of-round or taper with a micrometer. II not within specifications, replace or recondition crankshaft. If within specifications and new bearing is to 01634 be installed, measure maximum diameter of crankpin to determine new bearing size required. Figure 3. Gauging Plastic on Crankpin 5. If within specifications, measure new or used bearing clearances with P!astigage or equivalent. IMPORTANT: If bearing is being fitted to out-ofround crankpin. be sure to fit maximum diameter of crankpin. If bearing is fitted to minimum diameter, and crankpin is out-of-round .001", interference between bearing and crankpin will result in rapid bearing failure. a. Place a piece of gauging plastic the full width of crank- pin (parallel to crankshaft). (Figure 3) b. Install bearing connecting rod and cap. c. Install bearing cap and torque nuts evenlv to specifications. 01636 IMPORTANT: Do not turn crankshaft with gauging Figure 4. Measuring Connecting Rod Side Clearance plastic installed. 7. Coal bearing surface with oil. install rod cap and torque nuts to specifications. d. Remove bearing cap and, using scale on gauging plastic 8. \\ hen all connecting rod bearings have been installed, tap envelope, measure gauging plastic width al widest each rod lightlv (parallel to crankpin) to be sure thev have point. (Figure 2) clearance. 6. II clearance exceeds specifications, select a new, correct-9. Measure all connecting rod side clearances between con- size bearing and remeasure clearance. necting rod and side of crankpin. (Figure 4) 90-95693 485 ENGINE-6A-25 CONNECTING ROD and PISTON ASSEMBLIES REMOVAL 1. With oil pan. oil pump and cvlirider head removed, use a ridge reamer to remove any ridge and/or deposits from upper end of cylinder bore. IMPORTANT: Before ridge and/or deposits are removed, turn crankshaft until piston is at bottom of stroke and place a cloth on top of piston to collect cuttings. After ridge and/or deposits are removed, turn crankshaft until piston is at top of stroke and remove cloth and cuttings. 2. Inspect connecting rods and connecting rod caps for cylinder identification, if necessary, mark them. 3. Remove connecting rod cap and install Tool J-5239 (3/s"-24) on bolts. (Figure 1) Push connecting rod and piston assembly out of top of cylinder block. NOTE: It will be necessary to turn crankshaft slightly to disconnect some connecting rod and piston assemblies. DISASSEMBLY (METHOD "1") IMPORTANT: Piston Figure 3. Removing Piston Pin cannot be reused using Method "1". If bosses on pistons do not allow piston support Tool J9510- 1 to seat squarely on piston for press operations, modifications to tool are necessary. To allow adequate clearance for these bosses, turn or grind upper portion of tool to dimensions shown in Figure 2. NOTE: Installation of 181 cubic inch pistons may require additional grinding of support tool beyond dimensions shown in Figure 2. Modification of tool, as described, does not affect tool application on other pistons. a - Arched Base c - Adjustable Installer d - Piston Pin 1. Remove connecting rod b - Rod Support d - Piston Pin Guide Remover bearings from connecting 01646 Figure 4. Tool (J-24086-100) Parts Identification rods and caps. Figure 1. Guide Tool IMPORTANT: If con-J-5239 Installed necting rod bearings are being reused, place 3/8" (10mm) in a rack for reinstalla tion in original rod and cap. DISASSEMBLY (METHOD "2") 2. Use piston ring expander to expand rings and remove 1/8" 1. Use Tool Kit (J-24086-100). shown in Figure 4. from pistons. (3mm) 2. Position connecting rod onto tool rod support with rod support inserted between connecting rod end and piston. piston assembly in arbor 3. Place connecting rod and Align piston pin with hole located in top of arched base. press with piston on sup (Figure 5) 05041 port Tool J-9510-1 and press 3. Insert pin remover thru hole (located in top of arched piston pin out of connecting Figure 2. Piston Support base) and into piston pin hole. Press on pin remover to rod and piston. (Figure 3) remove piston pin. (Figure 5) Tool J-9510-1 6A-26 - ENGINE 90-95693 485 01637 a - Piston Pin Remover b - Arched Base 10072 c - Piston e - Rod d - Connecting Rod Support Figure 5. Removing Piston Pin CLEANING and INSPECTION Connecting Rods 1. V\ ash connecting rods in cleaning solvent and drv with compressed air. 2. Check for twisted or bent rods and inspect for nicks or cracks. Replace damaged connecting rods. Pistons 1. Clean varnish from piston skirts and pins with cleaning solvent. DO NOT ft IRE BRUSH ANY PART OF PISTON. Clean ring grooves with groove cleaner and make sure oil ring holes and slots are clean. 2. Inspect piston for cracked ring lands, skirls or pin bosses, way v worn ring lards, scuffed or damaged skirtsand eroded areas at top of piston. Replace pistons which are damaged or show signs of excessive wear. 3. Inspect grooves tor nicks or burrs which might cause rings to hang up. 4. Measure piston skirt (across centerline of piston pin) and check clearance as outlined under "Cvlinder Block". Piston Pins Piston and piston pin are a matched set and not serviced separately. I'm bores and piston pins must be free of varnish or scuffing. Measure piston pin with a micrometer and piston pin bore with a dial bore gauge or inside micrometer. If clearance is in excess of .00]" (,025mm) wear limit, replace piston and piston pin assembly. 90-95693 1-888 Remover and Installer Piston Pin Connecting Rod Bearing Tang Slots Support Figure 6. Piston Pin Installation Figure 7. Connecting Rod and Oven ENGINE - 6C-27 04991 153 CID 181 and 250 CID Figure 8. Connecting Rod and Piston Assembly 1. Heat piston pin end of connecting rod. MOTE: An oven or torch lamp (91-63209) is recommended to heat piston pin end of connecting rod prior to piston installa tion. (Figure 7) 2. Place support Tool J-9510-1 with spring and pilot in place on arbor press. 3. Position piston on connecting rod with notched side of piston (Figure 8) and connecting rod tangs aligned. 4. Place piston on support, indexing pilot through piston and rod. 5. Place installer (Figure6) on piston pin. start piston pin and press on installer until pilot bottoms in support. 6. Remove installer from connecting rod and pistor: assembly and check piston for freedom of movement on piston pin. 7. Allow connecting rod and piston assemblv to cool, then oil piston pin. REASSEMBLY (METHOD "2") 1. Lubricate piston pin, piston pin hole in piston and hoie in rod end with a light coat of engine oil. 2. Position rod onto rod support and piston onto rod end. Insert piston pin guide thru bottom piston pin hole and into connecting rod. Place piston pin thru lop side of piston. (Figure 9) 3. Adjust adjustable installer to setting specified on chart (which came with tool) for particular piston installation. Lock adjustable installer with jam nut. 4. Insert adjustable installer thru hole (located on top of arched base) and into piston pin hole. Carefully press on adjustable installer until installer bottoms-out on arched base to install piston pin. a - Jam Nut b - Adjustable Installer c - Arched Base d - Piston e - Connecting Rod f - Piston Pin g - Rod Support Figure 9. Installing Piston Pin 6A-28 - ENGINE 90-95693 485 PISTON RINGS All compression rings are marked on upper side of ring. When installing compression rings, make sure marked side is toward top of piston. Top ring is treated with molybdenum for maximum life. Oil control rings are 3-picce type, consisting of 2 segments (rails) and a spacer. Figure 10. Measuring Ring Gap Figure 11. Ring Gap Location 1. Select rings comparable in size to piston being used. 2. Slip compression ring in cylinder bore, then press ring down into cylinder bore about Vt" (6mm) (above ring travel). Be sure that ring is square with cvlinder wall. 3. Measure space or gap between ends of ring with a feeler gauge. (Figure 10) •L If gap between ends of ring is below specifications, remove ring and try another for fit. 5. Fit each compression ring to cylinder in which it will be used. 6. Clean and inspect pistons. 7. Slip outer surface of top and second compression ring into respective piston ring groove and roll ring entirely around groove (Figure 12) to make sure that ring is free. If binding occurs at any point, determine cause and, if caused by ring groove, remove by dressing with a fine cut file. If binding is caused bv a disto-ted ring, use a new ring. 8. Install piston rings as shown in Figure 11. a. Install oil ring spacer in groove and (except on 250) insert anti-rotation tang in oil hole. b. Hold spacer ends butted and install lower steel oil ring rail with gap properlv located. (Figure 11) c. Install upper steel oil ring rail with gap properly located. d. Flex oil ring assembly to make sure that ring is free. If binding occurs at any point, determine cause and, if caused by ring groove, remove bv dressing groove with a fine cut file. If binding is caused bv a distorted ring, use a new ring. e. Install second compression ring expander, then ring with gaps properlv located. f. Install top compression ring with gap in correct location. 9. Proper clearance of piston ring in piston ring groove is necessarv for proper ringaction and to reduce wear. Therefore, when fitting new rings, measure clearances between ring surfaces and groove. INSTALLATION IMPORTANT: Cylinder bores must be clean before piston installation. Referto Step 5. "Cylinder Block- Cylinder Honing." 1. Lubricate connecting rod bearings and install in rods and rod caps. 2. Lightlv coat pistons, rings and cvlinder walls with light engine oil. 3. With bearing caps removed, install Tool J-5239 (%") on connecting rod bolts. IMPORTANT: Early Model "181", No. 2 connecting rods have a ground recess on camshaft side to provide clearance for fuel pump lobe on camshaft. Be sure that No. 2 connecting rod is installed in same location and position. If connecting rod is replaced, then replace camshaft also, since replacement connecting rods are not ground for clearance, and replacement camshafts have a smaller fuel pump lobe. Figure 12. Checking Ring in Groove 90-95693 485 ENGINE-6A-29 4. Install each connecting rod and piston assembly iri respective bore. Pistons must have piston notch facing front of engine. I se Tool j-8037 to compress rings. (Figure 13) Guide connecting rod into place on crankshaft journal with Tool J-5239. I se light blows with hammer handle to install piston into bore. Hold ring compressor firmly against cvlinder block until all piston rings have entered cylinder bore. 5. Remove guide too^. 6. Install bearing caps and torque nuts to specification. XOTE: If bearing replacement is required, refer lo "Connecting Rod Bearings' . IMPORTANT: Be sure to install new pistons in same cylinders for which they were fitted and used pistons in same cylinders from which they were removed. Each connecting rod and bearing cap should be marked, beginning at front of engine. Figure 13. Installing Connecting Rod and Piston Assemblies CRANKSHAFT Crankshaft can be removed while engine is disassembled for CLEANING and INSPECTION overhaul or without complete disassembly. 1. Wash crankshaft in solvent and dry with compressed air. 2. Measure dimensions of main bearing journals and crank- REMOVAL pins with a micrometer for out-of-round. taper or under- size. 1. Remove flvwheel housing, coupler and flywheel. 3. Check crankshaft for run-out by supporting at front and 2. Remove starter motor. rear main bearing journals in "V " blocks and checkat front 3. Remove spark plugs. and rear intermediate journals with a dial indicator. t. Remove crankshaft pullev or torsional damper. 4. Replace or recondition crankshaft if not within specifica5. Remove oil pan and oil pump. tions. 6. Remove crankcase front cover. 7. Check connecting rod caps for cv linder number identification. If necessary, mark caps. 8. Remove connecting rod caps and push pistons to top of INSTALLATION bores. 9. Remove main bearing caps and lilt crankshaft out of cyl1. Install crankshaft gear as shown in Figure 1 B. inder block. 10. Remove rear main bearing oil seal and main bearings from cvlinder block and main bearing caps. I l. Remove crankshaft gear as shown in Figure 1A. 01652 06063 Figure 1A. Removing Crankshaft Gear Figure 1B. Installing Crankshaft Gear 6A-30 - ENGINE 90-95693 485 2. Install crankshaft as follows: a. Install rear main hearing oil seal in cylinder block and rear main bearing cap grooves. Install with lip of seal toward inside of engine. b. Lubricate lipof seal with engine oil. Keep oil off parting line surface. c. Install main bearings in cylinder block and main bearing caps, then lubricate bearing surface with engine oil. d. Install crankshaft, being careful not to damage bearing surfaces. e. Apply a thin coat of Perfect Seal to block mating surface and corresponding surface of cap only. Do not allow sealer on crankshaft or seal lip. f. Install main bearing caps with arrows pointing toward front of engine. g. Torque all except rear main bearing cap bolts to 10-12 lbs. ft. (14-16 N.m). Torque rear main bearing cap bolts to specifications, then tap end of crankshaft, first from rear then forward, with a lead hammer. This will line up rear main bearing and crankshaft thrust surfaces. Re- torque all main bearing cap bolts to specifications. h. Measure crankshaft end play with a feeler gauge. Force crankshaft forward and measure clcarance between front of rear main bearing and crankshaft thrust surface. (Figure 1C) 3. Install connecting rod and caps. 4. Install crankcase front cover. 5. Install oil pump and oil pan. CAMSHAFT MEASURING LOBE LIFT Figure 1C. Measuring Crankshaft End Play 6. Install crankshaft pulley or torsional damper. 7. Install starter motor. 8. Install flywheel, coupler and flywheel housing. 9. Install spark plugs and torque to specifications. !\OTE: Procedure is similar to checking valve timing. If im proper valve operation is indicated, measure lift of each push rod in consecutive order and record the readings. 1. Remove valve mechanism. 2. Position indicator with ball socket adaptor (Tool J-8520) on push rod. (Figure 2) 3. Rotate torsional damper slowl y in direction of rotation until lifter is on lowest position of cam lobe. 4. Set dial indicator on zero, then rotate damper slowly, or attach an auxiliarv starter switch and bump"' engine over, until push rod is in fully raised position. 5. Compare total lift recorded from dial indicator with "Specifications". 6. Continue to rota:e crankshaft until indicator reads zero. This will be a check on accuracy of original indicator reading. 7. If camshaft readings for all lobes are within specifications, remove dial indicator assemblv. 8. Install and adjust valve mechanism as outlined. Figure 2. Measuring Camshaft Lobe Lift 90-95693 485 ENGINE-6A-31 REMOVAL Camshaft Thrust Plate 1. Remove valve lifters. 2. Remove crankcase front cover. Camshaft Gear 3. Remove fuel pump. 4. Align timing gear marks, then remove 2 camshaft thrust Feeler Strip plate screws by working thru holes in camshaft gear. (Figure 3) 5. Pull camshaft and gear assemblv out thru front of block. IMPORTANT: Support camshaft carefully when removing to protect camshaft bearings. 01654 Figure 5. Measuring Camshaft End Play CAMSHAFT GEAR REPLACEMENT 1. If inspection (preceding) indicated that camshaft, gear or thrust plate should be replaced, remove gear from camshaft. 2. Place camshaft thru gear remover, place end of remover on table of a press and press shaft out of gear. (Figure 6) Figure 3. Timing Gear Marks INSPECTION 3. To assemble camshaft gear, thrust plate and gear spacer 1. Measure camshaft bearing journals with a micrometer for ring to camshafl. firmh supporl camshaf t at back of front out-of-round condition. If journals exceed .001" (.025mm) journal in arbor press. out-of-round. replace camshaft. 2. Check camshaft for alignment with "\ " blocks and dial indicator (Figure 4) for exact amount that camshaft is out-of-true. If out more than .002" (,05mm) dial indicator reading, replace camshaft. 3. Inspect camshaft gear and thrust plate for wear or damage. Measure camshafl end play J.001" to .005" (.03mm to . 1 mm)]. (Figure 5) Support 5loevo Camshaft 01689 01619 Figure 4. Checking Camshaft Alignment Figure 6. Removing Camshaft Gear 6A-32 - ENGINE 90-95693 485 4. Place gear spacer ring and thrust plate over end of shaft, and install woodruff key in shaft kevwav. Press shaft gear onto shaft until it bottoms against gear spacer ring. End clearance of thrust plate should be .001" to .005" (.03mm to .1mm). (Figure 5) INSTALLATION 1. Install camshaft and gear assemblv in engine block, being careful not to damage camshaft bearings or camshaft. 01654 Figure 7. Crankshaft Gear 2. Turn crankshaft and camshaft so that timing marks on gear teeth will lineup. (Figure 7) Push camshaft thrust plate to block screws and torque to specifications. 3. Check camshaft and crankshaft gear run-out with a dial indicator. (Figure 8) Camshaft gear run-out should not exceed .004" (.1mm) and crankshaft gear run-out should not exceed .003" (.07mm). 4. If gear run-out is excessive, remove gear and clean burrs from shaft, or gear must be replaced. 5. Check backlash between timing gear teeth with a dial indicator. (Figure 9) Backlash should not be less than .004" (.1mm). nor more than .006" (,15mm). 6. Install fuel pump. 7. Install crankcase front cover. 8. Pour G.M. Engine Oil Supplement or light engine oil over camshaft lobes and install valve lifters. 01620 Figure 8. Checking Timing Gear Run-Out 01621 Figure 9. Checking Timing Gear Backlash 90-95693 485 ENGINE-6A-33 CAMSHAFT BEARINGS REMOVAL With camshaft removed, inspect hearings for evidence of wear or damage. Replace defective bearings. Replace camshaft bearings while engine is disassembled for overhaul or without complete disassemblv of the engine. To replace bearings without complete disassemblv. remove cam shaft and crankshaft, leaving cvlinder heads attached and pistons in place. Before removing crankshaft, tape threads of connecting rod bolts to prevent damage to crankshaft. Fasten connecting rods against sides of engine so that rods will not hinder camshaft bearing replacement. 1. With camshaft and crankshaft removed, drive camshaft rear plug from cylinder block. a - Searing O.D. 1.999"-2.001" (50.77-50.83mm) Use 23-43293 Bearing Set Figure 10. Camshaft Bearing O.D. 6A-34 - ENGINE 90-95693 485 MOTE: This procedure is based on removal of bearings nearest center of engine first. Thus, a minimum number of turns are necessary to remove all bearings. 2. Using Tool Set J-6098-01, with nut and thrust washer installed to end of threads, position pilot in front camshaft bearing and install puller screw thru pilot. 3. Install remover and installer tool with shoulder toward bearing, making sure a sufficient amount of threads are engaged. 4. Using 2 wrenches, hold puller screw while turning nut. \\ hen bearing has been pulled from bore, remove tool and bearing from puller screw. (Figure 11) 5. Remove remaining bearings (except front and rear) in same manner. Position pilot in rear camshaft bearing lo remove rear intermediate bearing. 6. Assemble remover and installer tool on driver handle and remove front and rear camshaft bearings bv driving toward center of cvlinder block. (Figure 12) INSTALLATION Refer to Figure 10 for correct bearing set(s). Install front and rear camshafl bearings first. These bearings will act as guides for pilot and center remaining bearings being pulled into place. 1. Assemble remover arid installer tool on driver handle and install front and rear camshaft bearings bv driving toward center of cvlinder block. (Figure 12) IMPORTANT: Front bearing must be driven approx imately V»" (3mm) behind front of cylinder block to uncover oil hole to timing gear oil nozzle. 2. Using Tool Set J-6098-01, with nut and thrust washer installed lo end ol threads, position pilot in front camshaft bearing and install puller screw thru pilot. Figure 12. Removing and Installing Camshaft Bearings 3. Index camshaft bearing in bore, then install remover and installer tool on puller screw with shoulder toward bearings. 4. I sing 2 wrenches, hold puller screw while turning nut. After bearing has been pulled into bore, remove tool from puller screw and check alignment of oil hole in camshaft bearing. 5. Install remaining bearings in same manner. Position pilot in rear camshafl bearing to install rear intermediate bearing. 6. Install a new camshaft rear plug flush to 1/32" (.8mm) deep and parallel with rear surface of cylinder block. I se Perfect Seal on plug. 90-95693 485 ENGINE-6A-35 CYLINDER BLOCK CLEANING and INSPECTION 1. Wash cvlinder block ihoroughly in cleaning solvent and clean all gasket surfaces. 2. Remove oil gallerv plug.- and clean all oil passages. XOTE: Remot e plugs with a sharp punch or drill and prx out. "A" = At Right Angle to Center- line of Engine "B' : Parallel to Centerline of Engine Taper = Difference between "A" Measurement at Top of Cylinder Bore and "A" Measurement at Bottom of Cylinder Bore Out-of-Round - Difference between . 05042 "A" and "B" Figure 1. Cylinder Measurement 3. Clean and inspect waler passages in cylinder block. 4. Inspect cvlinder block for cracks in cylinder walls, water jacket valve lifter bores and main bearing webs. 5. Measure ihe cvlinder walls for taper, out-of-round or excessive ridge at top of ring travel (Figure l) with dial indicator. (Figure 2) Set gauge so that thrust pin must be forced in about Vt" (6mm) to enter gauge in cylinder bore. Center gauge in cv linder and turn dial lo "0" . Carefully work gauge up-and-down cvlinder to determine taper and turn gauge to different points around cvlinder wall to determine out-of-round condition. If cylinders exceed specifications, honing and/or boring are necessary. Figure 2. Measuring Cylinder Bore REPAIRS Cylinder Conditioning I iondilion of engine al lime of repair is important. I f inspection indicates lliat cvlinder block is acceptable, except for out-ofround or tapered cylinders, condition ihe block bv honing or boring. 6A-36 - ENGINE If cylinders have less than .005" (.1 mm) taper or wear, condition them w.th a hone and fit with high limit, standard size piston. A cylinder bore of less than .005" wear or taper mav not clean up entirelv w hen fitted to a high limit piston. To clean up bore entirely. in such a case, rebore for an oversize piston. If more than .005" taper or wear, bore and hone to smallest oversize thai permits complete resurfacing of all cylinders. When pistons are fitted (honing no longer necessary), clean (scrub) cvlinder bores with detergent and hot water. After cleaning, swab cylinder bores several times with lighl engine oil with clean cloth, then wipe with clean, dry cloth. Cylinder Boring Before using an\ tvpe boring bar. file off top of cylinder block to remove dirl or burrs. This will guard against a tilted boring bar and assures that rebored cv linder wall is al right angles to crankshaft. Measure piston, to be fitted, with a micrometer at center of piston skirt and at right angles to piston pin. Bore cylinder to same diameter as piston and hone cylinder to specifications and as outlined under "Cylinder Honing' and Piston Selection' . 3. Carefuliv follow instructions furnished by manufacturer of equipment being used. Cylinder Honing Follow hone manufacturer's recommendations for use of hone and cleaning and lubrication during honing. Occasionally, during honing operation, thoroughly clean cylinder bore and check piston for correct fit in cylinder. When finish honing a cylinder bore to fil a piston, move hone up-and-down to obtain very fine uniform surface finish marks in a cross-hatch pattern of approximately 30° to cvlinder bore. Finish marks should be clean bul not sharp and free from imbedded particles and torn or folded metal. Permanent I v mark piston for cylinder ic which it has been fitted and proceed to hone cylinders and fil remaining pistons. Thoroughly clean cv linder bores with hoi water and detergent. Scrub well with a stiff bristle brush and rinse thoroughly with hot water. Be absolutely certain that no abrasive material is allowed to remain in cvlinder bores, or it will rapidlv wear new rings and cylinder bores in addition to bearings lubricated by contaminated oil. Swab bores several limes with light engine oil with a clean cloth, then wipe with a clean, dry cloth. DO .NOT clean cylinder with kerosene or gasoline. Clean remainder of cylinder block lo remove excess material spread during Irjning operation. 90-95693 485 PISTON SELECTION d. Determine if piston to bore clearance is in acceptable DISTRIBUTOR LOWER BUSHING I. Check I SED piston to cvlinder bore clearance as follows: a. Measure "Cylinder Boer Diameter" with a telescope gauge |2'/2" (64mm) from top of cylinder bore]. b. Measure "Piston Diameter" (at skirt across centerline of piston pin). c. Subtract piston diameter from cylinder bore diameter to determine Piston to Bore Clearance". INSPECTION and REPLACEMENT Distributor lower bearing is a bronze bushing pressed into lower side of engine block. Its upper inside diameter pilots distributor shaft, and outside diameter (extending below block) pilots oil purr.p. Some engines have a thrust washer at upper end of bushing bore. Thrust washer, where used, may be replaced at same time bushing is replaced. Lower bushing ordinarilv will require only a clearance or wear check during engine overhaul. V\ hen distributor shaft-tobushing clearance exceeds .035" (.08mm). replace bushing, as follows, with oil pump and distributor removed: 01647 Figure 3. Removing Distributor Lower Bearing range. 2. If piston to bore clearance is not acceptable, check Parts Manual for oversize pistons. 3. If cylinder bore must be reconditioned, measure new piston diameter (across centerline of piston pin), then hone cylinder bore to correct clearance. 4. Mark piston to identify cylinder for which it was fitted. IMPORTANT: Later distributors use a bushing in distributor housing. Measuring clearance between cylinder block bushing and distributor shaft is not needed, since distributor shaft is undercut. 1. Install Tool J-9534-01 into bushing and remove bushing with a slide hammer. (Figure 3) 2. Clean bushing bore in block and check i'or burrs or damage. Figure 4. Install Distributor Lower Bearing 3. Lse tool with driver-bolt in driver handle to install driver into new bushing from large inside diameter. 4. Position bushing and driver to block and drive bushing in position (Figure 4). which is determined bv tool bottoming against block. 5. Remove tool from bushing. It is possible that bushing with minimum inside diameter will collapse enough during installation to slightly seize installer arbor. If this happens, remove installer tool with slide hammer in driver bolt hole of driver handle. \ 07 L: This will not damage bushing, and tool is designed for this purpose, should it occur. 90-95693 485 ENGINE-6A-37 OIL NOZZLE REPLACEMENT 01614 1. Remove nozzle with pliers. (Figure 5) 2. Drive now nozzle in place (oil hole in vertical position) with a suitable light plastic or rubber hammer. IMPORTANT: Later model engines DO NOT have an oil nozzle. A plug is used to seal this hole. Figure 5. Oil Nozzle Replacement OIL FILTER BYPASS VALVE and REPLACEMENT With oil filter removed, check spring and fiber valve for operation. Inspect for a cracked or broken valve. If replacement is necessary, pry valve out with screwdriver. Install and seat a new valve bv tapping in place with a 9/16 thin-wall deep socket. (Figure 6) 06059 Figure 6. Oil Filter By-Pass Valve 6A-38 - ENGINE 90-95693 485 SECTION 6 - ENGINE PART B - MERCURY MARINE 4 CYLINDER ENGINE INDEX Page Page Torque SpecificationsTools/Lubricants/SealantsEngine SpecificationsGeneral Engine Rotation Engine IdentificationOil Flow - 470Oil Flow - 485/488Bearing FailuresPiston Failures Pre-lgnition Detonation Front/Rear MountsMCM Engine Front MountFlywheel Housing/MCM Engine Rear Mount MIE 470 Engine MountsIntake ManifoldRocker Arm CoverValve ClearanceRocker Arm/Push RodHydraulic Valve LiftersValve Stem Oil Seal and/or Valve SpringCylinder Head and Valves Cylinder Head Removal Valve Removal Cylinder Head Conditioning Valve Conditioning Valve Spring Inspection Valve Installation 6B-1 6B-4 6B-5 6B-9 6B-9 6B-9 6B-10 6B-11 6B-12 6B-12 6B-12 6B-13 6B-14 6B-14 6B-15 6B-16 6B-17 6B-18 6B-19 6B-19 6B-20 6B-22 6B-23 6B-23 6B-23 6B-23 6B-25 6B-25 6B-26 Cylinder Head Installation 6B-26 Alternator Rotor 6B-27 Stator 6B-28 Front Cover and Circulating Pump 6B-29 Timing Chain and Sprockets 6B-31 Checking Timing Chain Deflection 6B-31 MCM Engine Coupler and/or Flywheel 6B-32 MIE Flywheel Assembly 6B-32 Removal 6B-32 Inspection 6B-32 Installation 6B-32 Engines without Weight Kit 6B-32 Engines with Weight Kit 6B-32 470/485 Flywheel Ring Gear (43-97433A1) Replacement 6B-33 Oil Pan 6B-34 Oil Pump 6B-35 Oil Seal (Rear Main) 6B-36 Camshaft 6B-37 Camshaft Bearings 6B-38 Crankshaft 6B-39 Main Bearings 6B-41 Connecting Rod Bearings 6B-42 Piston and Rod AssemblY 6B-45 Piston Rings 6B-47 Cylinder Block 6B-48 Repairs 6B-49 Piston Selection 6B-49 Oil Filter Adaptors 6B-51 TORQUE SPECIFICATIONS Fastener Location Lbs. Ft. (N.m) Lbs. In. (N.m) Alternator Rotor to Crank 75 (102) Camshaft Extension Shaft (Note 1) 60 (81) Camshaft Thrust Plate 115 (13) Camshaft Sprocket Screws 150 (17) Carburetor Mounting (2 BBL) 20 (27) Carburetor Mounting (4 BBL) 20 (27) Chain Tightener Bolt 20 (27) Connecting Rod Cap 40 (54) Coupler/Flywheel (MCM) See Figures 1 and 2 Cylinder Head (Note 2) 130 (176) Distributor Clamp 15 (20) Flywheel (MIE) 75 (102) Flywheel Drive Plate (MIE) 5/16-18 18 (24) Flywheel Weight Kit (MIE) 7/16-14 75 (102) Flywheel Housing to Block 30 (41) Front Mount to Block 50 (68) Impeller Cover 15 (20) Impeller Screw 5/16-18 15 (20) Impeller Nut 1/2-20 (Note 1) 40 (54) Main Bearing Cap 55 (75) Manifold to Head (Exhaust) 25(34) Manifold to Head (Intake) 25 (34) Oil Pan 130 (15) Oil Pan Drain Plug 20 (27) Oil Pump Cover 120 (14) Oil Pump to Block 25 (34) Oil Pump Pickup 20 (27) Oil Tube to Block 20 (27) Rear Mount to Transmission (MIE) 50 (68) Rocker Arm Cover 90 (10) Rocker Arm Bolt (Ncte 3) 20 (27) Side Cover 15 (20) Spark Plug (14mm) 15 (20) Starter Motor 60 (81) Stator to Front Cove45 (5) Timing Chain Cover 15 (2D) Transmission to Flywheel Housing (MIE) 50 (63) Water Pump Cover 15 (20) NOTES: 1. Left Hand (L.H.) Thread 2. Torque with Valves Closed and in 3 Steps. Retorque After First Start bp. 3. Torque with Valves Closed. IMPORTANT: DO NOT intermix stud/nut combinations. 11-33962 11/16" Hex 11-98533 5/8" Hex ESNA Crownlock 5/8" Hex Crownlock A - 45 Lbs. Ft. (61 N.m) 269-H B - 35 Lbs. Ft. (42 N.m) C - 40 Lbs. Ft. (54 N.m) D - See Figure 3. For Coupler Wrench Modification Figure 1. MCM 470 (Serial No. 6218036 and Below), MCM 485 Engine Coupler/Flywheel a - 25-30 Lbs. Ft. (34-41 N.m) b - 75 Lbs. Ft. (120 N.m) Figure 2. MCM 470R (Serial No. 6218037 and Above), MCM 488R Engine Coupler/Flywheel 6B-2 - ENGINE 90-95693 485 Engine Coupler Wrench, 91-35547, may not work on the lat er couplers. Modify wrench as shown in Figure 3, so it will work both earlier and later style couplings. a - Original 91-35547 Wrench b - Heat and Bend as Shown c - Grind Area Shown Slightly d - Heat and Bend as Shown (This is what wrench should ,ook like when it's done) Figure 3. Modifying Engine Coupler Wrench 90-95693 485 ENGINE-6B-3 TOOLS/LUBRICANTS/SEALANTS MERCURY MARINE SPECIAL TOOLS 91-24697 Piston Ring Expander 91-35547 Engine Coupler Wrench 91-75691 Oil Pump Alignment Tool KENT-MOORE SPECIAL TOOLS Can be ordered from: Kent-Moore Tools, Inc. 29784 Little Mack Roseville, Ml 48066 Phone 313-774-9500 J5892 Valve Spring Compressing J8062 Valve Spring Compressor J8056 Valve Spring Tester J8101 Valve Guide Cleaner J8089 Carbon Remover Brush J24086-100 Piston Pin Tool J3936-03 Piston Ring Groove Cleaner J8037 Piston Ring Compressor J5239 Connecting Rod Guide Tool J8087 Cylinder Bore Checker J26817 Seal Installer J6978-E Alternator Rotor Remover J21058-20 Alternator Rotor Installer OWATONNA SPECIAL TOOLS Can be ordered from: Owatonna Tools, Inc. 2013 Fourth St., N.W. Industrial Part Warehouse Owatonna, VIN 55060 Phone 507-455-2626 T71P-6513B Valve Lifter Collapsing Tool T52L-6085AEE Valve Guide Reamer Kit T65L-6250-A Bearing Installation Kit LUBRICANTS/SEALANTS 92-34227 Quicksilver Perfect Seal 92-86154A1 Quicksilver 2-4-C Multi-Lube 92-91601-1 Quicksilver RTV Sealer 92-32609-1 Quicksilver Loctite ENGINE SPECIFICATIONS UNIT OF MEASUREMENT in. (mm) MODEL 470 485 488 CU. IN. DISPLACEMENT 224 (3.7 litres) CYLINDER BORE: Diamete DiameteDiamete r rr 4.3602-4.3609 (110.749-110.767) Ou OuOu t tt o oo f ff Roun RounRoun d dd Production .0005 (.0127) Max. Service .0015 (.0381) Max. Taper Productio ProductioProductio n nn Thrust Side .0005 (.0127) Max. Relief Side .0005 (.0127) Max. Service .003 (.076) Max. CYLINDER BLOCK: Dec DecDec k kk Heigh HeighHeigh t tt Production 10.255-10.265 (260.477-260.731) (Not (Not(Not e ee 1 11 ) )) Service 10.240 (260.096) Min. Mai MaiMai n nn Bearin BearinBearin g gg Production 2.9417-2.9425 (74.7191-74.7395) Bor BorBor e ee Diamete DiameteDiamete r rr Service 2.9435 (74.7649) Max. Hydrauli HydrauliHydrauli c cc Lifte LifteLifte r rr Production .875-.876 (22.225-22.250) Bor BorBor e ee Diamete DiameteDiamete r rr Service .878 (22.301) Max. Camshaft Bore Diameter 2.1258-2.1268 (53.995-54.021) NOTE 1: Measured from center of main bearing bore to top of cylinder block. PISTON: CLEARANCE Production See Page 6B-50 Service See Page 6B-50 PISTON RING: COMPRESSION Groov GroovGroovGroovGroov e eeee Productio ProductioProductio n nn Top .0025-.004 (.07-.1) 2nd .0025-.004 (.07-1) Clearanc ClearancClearancClearancClearanc e eeee Servic ServicServic e ee Top .0025-.004 (.07-. 1) 2nd .0025-.004 (.07-. 1) Productio ProductioProductio n nn Top .010-.020 (.25-.5) Ga GaGaGaGa p pppp 2nd .010-.020 (.25-.5) Servic ServicServic e ee Top .010-.020 (.25-.5) 2nd .010-.020 (.25-.5) PISTON RING: OIL Groov GroovGroov e ee Production .0011-.0065 (.03-.15) Clearanc ClearancClearanc e ee Service .0011-.0065 (.03-.15) Ga GaGa p pp Production .010-.025 (.25-.6) Service .010-.025 (.25-.6) PISTON PIN: Diameter 1.0399-1.0402 (26.413-26.421) Production .0004-.0006 (.0102-.0152) Service .0004-.0006 (.0102-.0152) Fit in Rod .0006-0016 (.0152-.0406) Interference (Continued on Next Page) 90-95693 485 ENGINE-6B-5 MODEL 470 485 488 CRANKSHAFT: Diameter 2.7472-2.7482 (69.779-69.804) Mai MaiMaiMaiMai n nnnn Journa JournaJournaJournaJourna l llll Tape TapeTape r rr Production .0002 (.0051) Max. Service .0005 (.0127) Max. Ou OuOu t tt o oo f ff Roun RounRoun d dd Production .0002 (.0051) Max. Service .0005 (.0127) Max. Mai MaiMai n nn Brg BrgBrg . .. Clearanc ClearancClearanc e ee Production .0009-.0031 (.0228-.0787) Service .001-.003 (.03-.07) Rea ReaRea r rr Sea SeaSea l ll Are AreAre a aa Diamete DiameteDiamete r rr Production 3.748-3.752 (95.1992-95.3008) Service 3.745 (95.123) Min. Timin TiminTimin g gg Sprocke SprockeSprocke t tt (Not (Not(Not e ee 1 11 ) )) Production 1.380-1.381 (35.052-35.077) Service 1.379 (35.026) Min. Balance of Crankshaft (Note 2) Production .50 oz. in. Crankshaft End Play .006-.010 (.15-.25) Crankpi CrankpiCrankpiCrankpiCrankpiCrankpi n nnnnn Diameter 2.4979-2.4989 (63.447-63.472) Tape TapeTape r rr Production .0002 (.051) Max. Service .0005 ;.0127) Max. Ou OuOu t tt o oo f ff Roun RounRoun d dd Production .0002 (.051) Max. Service .0005 (.0127) Max. Ro RoRo d dd Brg BrgBrg . .. Clearanc ClearancClearanc e ee Production .0009-.0031 (.0228-0787) Service .001-003 (.03-.07) Rod Side Clearance .005-.012 (.15-3) NOTE 1: Because crankshaft has taper, measurement must be taken at rear half of sprocket area on crankshaft. NOTE 2: Balanced without connecting rods. ALTERNATOR ROTOR: Fron FronFron t tt Oi OiOi l ll Production 1.873-1.877 (47.5742-47.6758) Sea SeaSea l ll Diamete DiameteDiamete r rr Service 1.871 (47.5234) Min. CRANKSHAFT TIMING SPROCKET: Inside Diameter Production 1.381-1.382 (35.0774-35.1028) CAMSHAFT: End Play .002-.005 (.06-. 1) Lob LobLob e ee Lif LifLif t tt (Max. (Max.(Max. ) )) Intake .278 (7.061) (Note 1) .286 (7.2644) Exhaust .290 (7.366) (Note 1) .298 (7.5692) Lobe Wear Limit .009 (.2286) Max. Journal Diameter 2.1242-2.1248 (53.955-53.970) Clearance .001-.0026 (.0254-0660) Camshaft Runout .001 (.0254) Max. Timing Chain Deflection 1 (25) CYLINDER HEAD: Gasket Su'face Flatness .005 (.1) Max. NOTE 7: 466-7553 Camshaft with Green Paint I.D. -Intake: .300 (7.620), Exhaust: .308 (7.823) 466-8330 Camshaft with Orange Paint I.D. -Intake: .286 (7.2644), Exhaust: .310 (7.8740) 6B-6 -ENGINE 90-95693 485 MODEL 470 485 488 VALVE SYSTEM: Lifter Hydraulic Rocker Arm Ratio 1.73:1 Collapsed Tappet Gap .110-.210 (2.794-5.334) Fac FacFac e ee Angl AnglAngl e ee Intake 44° 29° 44° Exhaust 44° Sea SeaSea t tt Angl AnglAngl e ee Intake 45° 30° 45° Exhaust 45° Seat Runout (Int. Exh.) .002 (.0508) Max. Seat SeatSeat Widt WidtWidt h hh Intake .060-080 (1.524-2.032) Exhaust .060-080 (1.524-2.032) Ste SteSteSteSte m mmmm Clearanc ClearancClearancClearancClearanc e eeee Productio ProductioProductio n nn Int. .001-.0027 (.0254-.0686) Exh. .001-.0027 (.0254-.0686) Servic ServicServic e ee Int. .0037 (.0940) Max. Exh. .0052 (.1321) Max. Spring SpringSpringSpringSpringSpringSpring s ssssss (Not (Not(Not(Not(Not(Not(Not e eeeeee 1 111111 ) )))))) Free Length 2.03 [2-1/32 (52)] 2.18 [2-3/16 (55)] Pressur PressurPressur e ee Lbs LbsLbs . .. Ft FtFt . .. Closed 76-84 at 1.81 [1-13/16] [103-113 N.m at (46)] 90-100 at 1.86 [1-55/64] [122-136 N.m at (47)] Open 240-265 at 1.33 [1-21/64] [325-359 N.m at (34)] 255-275 at 1.36 [1-23/64] [346-372 N.m at (35)] Installe InstalleInstalle d dd Heigh HeighHeigh t tt ± ±± 1/32 1/321/32 " "" (,8mm (,8mm(,8mm ) )) Intake 1.81 [1-13/16 (46)] 1.86 [1-55/64 (47)] Exhaust 1.81 [1-13/16 (46)] 1.86 [1-55/64 (47)] Damper None External Spring SpringSpringSpringSpringSpringSpring s ssssss (Blu (Blu(Blu(Blu(Blu(Blu(Blu e eeeeee Stripe StripeStripeStripeStripeStripeStripe ) )))))) (Not (Not(Not(Not(Not(Not(Not e eeeeee 1 111111 ) )))))) Free Length 2.28 [2-9/32 (60)] Pressur PressurPressur e ee Lbs LbsLbs . .. Ft FtFt . .. Closed 82-94 at 1.90 [1-29/32] [111-127 N.m at (48)] Open 214-238 at 1.30 [1-19/64] [290-322 N.m at (33)] Installe InstalleInstalle d dd Heigh HeighHeigh t tt ±1/32 ±1/32±1/32 " "" (,8mm (,8mm(,8mm ) )) Intake 1.90 [1-29/32 (48)] Exhaust 1.90 [1-29/32 (48)] Damper Internal Coil Spring SpringSpringSpringSpringSpringSpring s ssssss (Re (Re(Re(Re(Re(Re(Re d dddddd Stripe StripeStripeStripeStripeStripeStripe ) )))))) (Not (Not(Not(Not(Not(Not(Not e eeeeee 1 111111 ) )))))) Free Length 2.135 [2-9/64 (54)] Pressur PressurPressur e ee Lbs LbsLbs . .. Ft FtFt . .. Closed 120-140 at 1.795 [1-51/64] (163-189 N.m at (46)] Open 324-364 at 1.275 [1-9/32] [439-493 N.m at (32)] Installe InstalleInstalle d dd Heigh HeighHeigh t tt ± ±± 1/32 1/321/32 " "" (,8mm (,8mm(,8mm ) )) Intake 1.795 [1-51/64 (46)] Exhaust 1.795 [1-51/64 (46)] Damper Internal Coil NOTE 7; Test Springs with Damper Installed 90-95693 485 ENGINE -6B-7 a - Torque to 40-45 Lbs. Ft. (54-61 N.m) b- 155" (3.937mm) Min. Both Sides c - Remove Metal From This Boss To Maintain Weight d - 6.6035"-6.6065" (167.7289-167 8051mm) e - 700" (17.780mm) Min. f - .100" (2.540mm) Min. Both Sides g - Production: 2.6522"-2.6530" (67.3658-67.3862): (Service: 2.6522"-2.6540" (67.3658-67.5116mm)] - Minor Diameter In Plane of Web In As Machined Condition. Measure at X-Y or Z. Major Diameter May Exceed Limits By Amount Following. Diameter Measurements Not to Vary In Excess of Production: .003" (,0762mm) [Service: .005" (,127mm)] Between "X" and "Y" (Octant Angle) or Between "Y" and "Z" (Octant Angle) or .0004" (,01016mm) Between "X" and "Z" (Quadrant Angle including Above Angles) Diametral Deviation (Barrel Shape - Hojr Glass or Taper) When Measured In Plane Thru "Y" Containing The Axis Not to Exceed .0006" (.01524mm) Per Inch (25mm) Between Any Two Measuring Points and 0004" (,01016mm) Per Inch In Length of Journal h - Diameter at "W" - Production: 1,0386"-1 03S3" (26.3804426.39822mm): [Service: 1.0386"-1.0395" (26.38044-26.40330 mm)] Piston Pin Hole Size To Be Measured In Plane of Web. Out of Round When Measured In Plane of Web - Diametral Dimension "V" To Be .0001" (.00254mm) Greater To .0004" (.01016mm) Smaller Than Diametral Dimension "W" Diametral Deviation ;Barrel Shape - Hour Glass or Taper) When Measured In Plane Thru "W" Containing The Axis Must Not Exceed .0015" (,0381mm;. Per Inch (25mm) and Not To Exceed 001" (.0254 mm) Total i - 1.550" (39.37mm) FINISHED WEIGHTOF ASSEMBLED ROD COMPLETE ROD 779-791 GRAMS PISTON PIN END 204-210 GRAMS CFANKSHAFTEND 575-581 GRAMS Figure 1. Connecting Rod a - Runout of These Surfaces Must Be Within .0025" (.0635mm) Total Indicato- Runout In Relation To Crankpin 3ore b - ,9985"-1.0015" (25.3619-25.4381 mm) c - These Surfaces Must Be In A True Plane Within .010" ( 254mm) Total Indicator Runout Figure 2. Connecting Rod 6B-8 - ENGINE 90-95693 485 GENERAL Some repairs, lhal are listed in this section, must be comj iletcd ENGINE IDENTIFICATION with engine removed from boat. Lngine removal depends upon type of repair and boat design. Place engine on repairstand for If the engine serial number and/or model deeals are missing, major repairs. the following will help in determining what model il is. Look for stamped code number in cylinder head. Also look at valve Lubricate all moving parts (during reassembl v) with engine oil. spring for color code. Apply Perfect Seal on threads of and under head of cylinder head bolts and on threads of all cvlinder block external bolts, screws and studs. Cubic inch displacement of each MerCruiser model is listed below. Model No. of Cylinders Cu. In. Displacement MIE 470 4 224 (3.7 Itr.) MCM 470 4 224 (3.7 Itr.) MCM 485 4 224 (3.7 Itr.) MCM 488 4 224 (3.7 Itr.) ENGINE ROTATION Kngine rotation terminology at limes has caused confusion. To clarify, engine rotalion is determined by observing flvwhee! rotation from the rear (transmission or stern driveend) of the engine looking forward (water pump end). PROPELLER ROTATION IS NOT NECESSARILY THE SAME as engine rotation. Vi hen ordering replacement engines, short blocks or parts for engines, be certain :o check engine rotation. Do not relv on propeller rotation in determining engine rotation. a - "Stamped" Number Location of Stamped Number MCM/MIE 470 - Stamped "0" or no stamp at all in cyl( L.H.) inder head. Single coil valve springs with orange stripe. MIE 470 (R.H.) - Same as above plus 1/4" thick ring between cylinder block and distributor. MCM 485 - Stamped "5" in cylinder head. Valve springs have internal dampener and Red or Blue stripe. MCM 488 - Stamped "8" in cylinder head. Valve springs have external dampener around spring and Green stripe. a - Left Hand Rotation (CCW) - All Stern Drive (MCM) Engines. MIE Inboa-d L.H. (Standard) Rotation b - Right Hand Rotation (CW) - MIE Inboard R.H. (Opposite) Rotation 90-95693 485 ENGINE-6B-9 OIL FLOW - 470 90-95693 485 6B-10 - ENGINE OIL FLOW - 485/488 90-95693 485 ENGINE -6B-11 BEARING FAILURES PISTON FAILURES PRE-IGNITION Pre-ignition is abnormal fuel ignition, caused bv combustion chamber hot spots. Control of the start of ignition is lost, as combustion pressure rises too earlv, causing power loss and rough running. The upward motion of the piston is opposed by the pressure rise. This can result in extensive damage to the internal parts from the high increase in combustion chamber temperature. (Figure 1) Pre-lgnition Causes 1. Hot spots in the combustion chamber from glowing deposits (due in turn to the use of improper oils and/or fuels). 2. Overheated spark plug electrodes (improper heat range or defective plug). 3. Any other protuberance in the combustion chamber, such as an overhanging piece of gasket, an improperly seated valve or any other inadequately cooled section of material which can serve as a source. Figure 1. Pre-lgnition Damage 90-95693 485 6B-12 - ENGINE DETONATION Detonation, commonly called "fuel knock" . "spark knock"" or carbon knock , is abnormal combustion of tbe fuel which causes the fuel to explode violently. The explosion, in turn, causes overheating or damage to the spark plugs, pistons, valves and. in severe cases, results in pre-ignition. (Figure 2) I se of low octane gasoline is one of the most common causes of detonation. Even with high octane gasoline, detonation could occur if engine maintenance is neglected. Other Causes of Detonation IMPORTANT: Use of improper fuels will cause engine damage and poor performance. 1. Over-advanced ignition timing. 2. Lean fuel mixture at or near full throttle (could be caused by carburetor or leaking intake manifold). 3. Cross-firing spark plugs. 4. Excess accumulation of deposits on piston and/or combustion chamber (results in higher compression ratio). 5. Inadequate cooling of engine by deterioration of cooling system. Engine failures, which result from the foregoing conditions, are beyond the control of Mercury Marine, therefore, no warranty will apply to failures which occur under these conditions. Figure 2. Detonation Damage 90-95693 485 ENGINE-6B-13 FRONT/REAR ENGINE MOUNT MCM ENGINE FRONT MOUNT 6B-14 - ENGINE 90-95693 485 FLYWHEEL HOUSING/MCM ENGINE REAR MOUNTS 90-95693 485 ENGINE-6B-15 MIE 470 ENGINE MOUNTS a - Lockwasher b - Tab Washer c - Nuts d - Rubber Inset (Cannot Be Removed) e - Front Engine Mount f - Rear (Transmission) Mount g - Flywheel Housing 6B-16- ENGINE 90-95693 485 INTAKE MANIFOLD REMOVAL 5. If gap is more than specified, do either "a", "b" or "c". a. Rerrove cylinder head. I sing new head gasket, reposi1. Remove manifold assemblv and discard gasket. tion head until gap is within specifications. 2. Carburetor mav be removed from intake manifold, if b. Use RTV Sealer on low surface, then put manifold necessary. gasket on. c. Replace cylinder head and recheck gap. CLEANING/INSPECTION INSTALLATION 1. Remove all gasket material. 2. Clean manifold in a suitable solvent and drv with compressed air. 1. Apply Perfect Seal on both surfaces of intake manifold lo cylinder head gasket. Position new gasket and intake mani 3. Inspect manifold. fold on cylinder head. Install fastener bolts with flat 4. Inspect for misalignment of cvlinder head and cylinder washers. (Figure 2) Torque fasteners to specifications. block. (Figure 1) 2. Use new gasket and install carburetor, if removed. Torque fasteners to specifications. IMPORTANT: Gap must be within specification or 3. Connect the following: engine oil may be drawn into intake manifold. This in turn will cause engine to burn oil. a. Water hoses to manifold. b. Fuel line to carburetor. c. Crankcase breather hose to flame arrestor. d. Fuel pump vent tube to carburetor. e. Carburetor linkage to manifold. Lubricate swivel points. f. Throttle cable. g. Connect wires to choke cover. 4. Pressure check the cooling system, using automotive radiator cap tester, follow tool manufacturer's instructions. a - Cyl. Head Surfcae b - Cyl. Block Surface c - Max. Gap .020" (,5mm) Figure 1. Measuring Gap 90-95693 485 ENGINE-6B-17 MCM 488R Engine^^ " Oi Cooler MCM 488R Engine^^ " Oi Cooler Figure 2. Intake Manifolds ROCKER ARM COVER REMOVAL 2. Remove all gasket material. 3. Inspect all gasket surfaces. 1. Remove spark plug leads. 2. Disconnect crankcase ventilation hose at rocker arm cover. INSTALLATION 3. Remove throttle cable (some models). 4. Remove attaching bolts. 1. Use a new gasket and install rocker arm cover and torque to specifications. 5. Remove rocker arm cover and gasket. 2. Connect all parts previously removed. CLEANING and INSPECTION 1. W ash cover in solvent and drv with compressed air. 6B-18 - ENGINE 90-95693 485 VALVE CLEARANCE IMPORTANT: Valve clearance is not adjustable. If a. Install tool as shown. Firmly push on handle until lifter clearance is not correct, it will be necessary to is completely collapsed. change the push rod to one of the correct length so b. Refer to "Specifications" for correct clearance (disthat proper clearance can be achieved. Read in tance between end of valve stem and face of rocker structions COMPLETELY BEFORE checking clear- arm). ance to prevent bending push rods. c. If clearance is less than specified, install a shorter push roc than was originally in engine. If clearance is more 1. With No. 1 piston at TDC (firing), check clearance of than specified, install a longer push rod. following valves (Figure 1): d. After installing new push rod, recheck valve clearance. • No. 1 - Intake and Exhaust • No. 2-Intake • No. 3 - Exhaust ENGINE PUSH ROD LENGTHS • No. 4 - Intake Lengths Color Code Mercury Marine Part Number 8.595"-8.625" (218.313-219.075mm) None or Red 67502-3 8.625"-8.655" (219.075-219.837mm) None 67502-5 8.655"-8.685" (219.837-220.599mm) Blue 67502-4 8.685"-8.715" (220.599-221.361mm) Yellow 67502-6 a - Rocker Arm b - T711P-6513A Tool c - Measure Clearance Figure 1. Checking Valve Clearance ROCKER ARM/PUSH ROD 112883 REMOVAL l. Ret mo\e rocker arm cover. IMPORTANT: Place rocker arms, rocker arm ful crums and push rods in a rack so that they may be reinstalled in same location. 2. Remove rocker arm bolts, fulcrums, rocker arms arid push rods. CLEANING and INSPECTION 1. Clean parts in solvent and drv with compressed air. 2. Inspect each rocker arm for wear. Replace worn rocker arms. 3. Check push rod ends and fulcrum for excessive wear. Replace if necessary. 4. Check push rods for bent condition. INSTALLATION Install push rods. Be sure that push rods seat in lifter socket. (Figure 1) Lubricate fulcrums and rocker arms with engine oil or Engine Oil Supplement. Install rocker arms, fulcrums and rocker arm fastening bolts. DO NOT tighten bolts at this time. IMPORTANT: Torquing of rocker arm bolts (Step 3) and checking valve clearance (preceding) are both done with valve in closed position. Time can be saved by completing both of these steps at the same time. 2. Rotate crankshaft 360° (l complete revolution) and check clearance of following valves: • No. 2 - Exhaust • No. 3 - Intake • No. 4 - Exhaust 90-95693 485 ENGINE - 6B-19 4. Rotate engine 360° (1 complete revolution) and torque remaining rocker arm bolts to specifications. Refer to Step 2 of "Valve Clearance" for remaining rocker arms. 5. Install rocker arm cover. a - Push Rod b - Lifter (Note Socket) c - Push Rod Installed into Lifter Socket Figure 1. Installing Push Rod 3. With No. 1 piston at Tl)C (firing) .torque rocker arm bolls (to specifications) as outlined in Step 1 of "Valve Clearance". (Figure 2) HYDRAULIC VALVE LIFTERS Figure 2. Torquing Rocker Arm Bolts REMOVAL 1. Remove rocker arm cover. 2. Remove valve mechanism. 3. Remove bolts with "(.)" ring- and remove side cover. 4. Lift out lifters. (Figure i I I'lace lifters in order so that lifter will be reinstalled in same location. 09801 a - Lifter b - Pointed Tool Figure 1. Removing Hydraulic Valve Lifters a - Lockring b - Lifter Assembly c - Small Screwdriver Figure 2. Removing Lockring DISASSEMBLY IMPORTANT: Lifters can be disassembled, cleaned and reinstalled. If any parts are worn, lifter must be replaced as an assembly. 1. Lse small screwdriver or needle-nose pliers to remove lockring. (Figure 2) 2. Lightly tap top end of lifter assemblv on flat surface to remove push rod cup, plunger/check valve assembly and spring. (Figure 3) ^Se SraS 09806 68-20 - ENGINE 90-95693 485 09805 a - Lockring b - Push Rod Cup c - Plunger/Check Valve Assembly d - Plunger Spring e - Lifter Body Figure 3. Lifter Components CLEANING and INSPECTION 1. Thoroughly clean all parts in cleaning solvent and dry them with compressed air. 2. Carefully inspect all parts for wear. If any parts are damaged or worn, entire lifter assembly must be replaced. If outside of liller body is scuffed or worn, inspect cvlinder block lifter bore. If boltom of lifler is worn, inspect camshaft lobe. If push rod seat is worn, inspect push rod. REASSEMBLY IMPORTANT: Work in clean area. 1. Inject engine oil in lifter body to approximately '/2-full. 2. Set plunger spring in lifter bodv. (Figure 3) 3. Place plunger assemblv (check valve end down) in lifter body. (Figure 3) 4. Lse small punch to unseal check ball (located in bottom of plunger assembly) and push plunger (compressing spring) until top of plunger is below hole in side of lifter body. (Figure 4) Now insert small punch through side hole to hold plunger in position. 5. Remove punch from check ball and position push rod cup in lifter body. 6. Install lockring in groove and remove punch from lifter body side hole. INSTALLATION 1. Lubricate all camshaft lobes, lifter bores and entire lifter with G.M. Engine Oil Supplement or engine oil. 2. Replace lifter into lifter bore from which it was removed. 3. Install valve mechanism. 4. Install cover, using new gasket and new "0 rings on cover attaching bolts. Torque to specifications. 5. Install rocker arm cover. 09804 a - Lockring c - Lifter Body b - Push Rod Cup d - Small Punches Figure 4. Assembling Lifter 90-95693 485 ENGINE-6B-21 VALVE STEM OIL SEAL and/or VALVE SPRING 1. Remove rocker arm cover. 2. Remove spark plugs. 3. Remove rocker arm bolt, fulcrum, rocker arm and push rod on cylinder to be serviced. 4. Position piston at top dead center to prevent valve from dropping out of valve guide. NOTE: A tool to apply air to cylinder is available thru local jobbers. Engines use tapered spark plugs. 5. Install rocker arm bolt (from where boh was removed) and position compressor tool as shown in Figure 5. Compress valve spring and remove retainer locks. Remove tool, then remove retainer, valve spring and seal. (Figure 6) 6. Install new valve stem seal. Place spring in position over valve and install valve spring retainer. Compress valve springand install spring retainer locks. (Figure 5] Remove compressor tool ar.d bolt. IMPORTANT: If new spring was installed, check installed spring height. 7. Install spark plugs and wires. 8. Install valve mechanism. 9. Install rocker arm cover. a - Retainer Locks b - Spring Retainer c - Valve Spring d - Seal e - Valve Figure 6. Valve and Related Parts a - J-5892-1 Tool b - Rocker Arm Bolt Figure 5. Compressing Valve Spring 17650 6B-22 - ENGINE 90-95693 485 CYLINDER HEAD and VALVES CYLINDER HEAD REMOVAL 1. Remove intake and exhaust manifold. 2. Remove rocker arm cover and valve mechanism. 3. Disconnect spark plug wires and remove spark plugs and coil bracket. 4. Disconnect water hose. 5. Remove bolts, then remove cylinder head assembly and gasket. VALVE REMOVAL 1. Remove cylinder head. 2. Compress valve springs (Figure 1) with valve spring compressor and remove retainer locks. 3. Remove spring compressor tool, spring retainer, valve spring, valve stem seal and valve, ldentifv al valves to reinstall in same location. 4. Repeat Steps 2 and 3 to remove each valve. a - J-8062 Tool d - Spring Retainer b - Valve Spring e - Retainer Locks c - Valve Stem Figure 1. Removing and/or Installing Valves a - Valve Stem b - Dial Indicator c - Valve Guide Figure 3. Checking Valve Stem Clearance CYLINDER HEAD CONDITIONING 1. Remove deposits from combustion chambers with Tool J-8089. 2. Clean all gasket surfaces. 3. Thoroughly clean valve guide bores with valve guide cleaning tool. 4. Clean all bolts and bolt holes. 5. Check cylinder head for cracks and inspect gasket surface for burrs and nicks. 6. Check cylinder head for flat gasket surface (Figure 2). (See "Specifications".) If necessary to refinish cylinder head gasket surface, do not plane more than .010" (,25mm). a - Check Diagonally b - Check Diagonally c - Check Across Center Figure 2. Typical Cylinder Head Flatness 90-95693 485 ENGINE-6B-23 7. Measure valve stem clearance (Figure 3) as follows: a. Clamp dial indicator on one side of cylinder head rocker arm cover gasket rail, locating indicator so that movement of valve stem from side-to-side (crosswise to head) will cause direct movement of indicator stem. Indicator stem must contact side of valve stem just above valve guide. (Figure 3) b. With valve head dropped about 1/16" (2mm) off valve seat, move valve stem from side-to-side. c. If clearance exceeds specifications, it will be necessary to ream valve guides for next oversize valve (Figure4): (1) Valve guide to be reamed must be refinished before doing any checking or refacing of valve seat. (2) After guide is refinished. seat also must be refaced to match guide. (3) Always use reamers in sequence (starting with smallest oversize reamer) when going from standard valve stem to an oversize. (41 Remove sharp corner (inside diameter) from top of valve guide. (5) Clean head assembly thoroughlv. 8. Check valve seat for runout. a. Install accurate gauge on tool positioned in valve stem guide. It is essential that valve guide bores are free of carbon or dirt b. Follow instructions of gauge manufacturer. If runout exceeds wear limit, reface valve and valve seat. 9. Check valve seat width (FigureS). a. Measure valve seat width. b. Reface valve seat, if width is not within specifications. (1) Closely coordinate refacing valve seat with refacing valve face so that finished seat and valve face are concentric, and specified interference fit will be maintained. This is important so that valve and seat have compression-tight fit. (2) Grind valve seats to correct angle (see "Specifications") . Remove onlv enough stock to clean up pits and grooves or to correct valve seat runout. (3) Finished valve seat must contact appropriate center of valve face. Apply ink (with felt tip pen) to refinished valve face. Install valve and rotate with light pressure. Remove valve and check seat contact. If seat contacts center of valve face, contact is satisfactory. If seat contact is at top edge of valve face, lower the valve seat. If seat contact is a) bottom edge of valve face, raise the valve seat. (4) After seat has been refaced. recheck seat width. If width exceeds maximum limit, remove enough stock from top edge and/or bottom edge of seat to reduce width to specifications. (5) If valve and/or seat has been refaced. check clearance between rocker arm seat and valve stem. Refer to 'Valve Clearance' . a - T52L-6085-AEE Tool b - Valve Guide Figure 4. Reaming Valve Guides a - Top Edge "Approach AngJe" b - Seat Angle c - Seat Width d - Bottom Edge Figure 5. Valve Seat in Cylinder Head 6B-24-ENGINE 90-95693 485 VALVE CONDITIONING 1. Clean deposits from valve head and stem. 2. Closely coordinate valve refacing operation with valve seat refacing operations so that finished angles of valve face and valve seat will meet specifications and provide compression- tight fit. 3. See "Specifications ", for valve face angle. Remove onlv enough stock to correct runout or to clean ud pits and grooves. If edge of valve head is less than 1/32" (,8mm) thick after grinding, replace valve. 4. If valve and/or seat has been refaced, check clearance between rocker arm seal and valve stem. Refer to "Valve Clearance" . VALVE SPRING INSPECTION 1. Check springs for correct pressure at specified spring lengths with Tool J-8056. (Figure 6) Follow tool manufacturer instructions. 2. Replace any spring not within specifications. Figure 6. Checking Valve Spring Pressure a J- 8056 Tool b - Valve Spring c 01594 Torque Wrench 17648 17549 17651 Figure 7. 470 Spring, Orang e Stripe Figure 8. 485 Spring, Red or Blue Stripe Figure 9. 488 Spring, Green Stripe 90-95693 485 ENGINE - 6B-25 3. Check each spring for "square ". Stand spring (closed coil end downward) and steel square (Figure 10) on flat surface. Slide spring up to square. 4. Revolve spring slowly and observe space between top coil of spring and square. Out-of-square limits are 5/64" (2mm). a - Valve Spring Closed Coil End b - Max. 5/64" (2mm) Figure 10. Checking Valve Spring Squareness VALVE INSTALLATION Lubricate valve stem and valve stern guide with Engine Oil Supplement. Insta.l each valve in port from which il was removed or to which it was lilted. 2. Install new stem seal on valve. 3. Install valve spring over valve, then install spring retainer. 4. Compress spring (using compressor tool) and install retainer locks. Make sure that locks are positioned properly in valve stem groove. 5. Measure assembled height of valve spring from surface of cylinder head spring seat to underside of spring retainer, (figure 11) If assembled height is greater than specifications. install spacer(s) below spring to reduce height to recommended dimension. DO NOT overshim. 05040 a - See Specifications Figure 11. Measuring Spring Height CYLINDER HEAD INSTALLATION NOTICE Low Compression Cylinder Head Gasket Kit (27-94954A1) lowers compression ratio from 8.8:1 to 8.2:1. Also basic timing must be lowered from 8C BTDC to 2° BTDC. This kit was primarily designed for use in countries outside the U.S.A. and Canada, where the fuel octane rating may be low. 1. Be sure that all gasket surfaces are clean. IMPORTANT: DO NOT use any gasket cement or sealer on Head Gasket, Cylinder Head or Cylinder Block. 2. Position new cylinder head gasket on cvlinder block with the word FRONT (stamped on gasket) toward front of engine and facing DOW N toward cylinder block (Figure 12). Make sure alignment dowel pins are through correct holes in head gasket. a - Cylinder Head Gasket c - Small Water Passage Holes b - Alignment Dowel Pins d - Large Water Passage Holes Figure 12. Cylinder Head Gasket Installation IMPORTANT: Check alignment of cylinder head and cylinder block as outlined under "Intake Mani fold". 3. Coat threads and underside of bolt head with Perfect Seal and install cvlinder head bolts. 6B-26 - ENGINE 90-95693 485 4. Follow torquing sequence shown in Figure 13. torque cylinder head bolts in three steps: • 55 lbs. ft. (75 N.m) • 90 lbs. ft. (122 N.m) • 130 lbs. ft. (176 N.m) IMPORTANT: Failure to properly torque cylinder head bolts can cause cylinder head gasket failure. Also, cylinder head bolts MUST be retorqued after engine has been brought to normal operating temperature. Failure to do this can result in head gasket failure. 5. Reinstall all components previously removed. Figure 13. Cylinder Head Bolt Torquing Sequence ALTERNATOR ROTOR REMOVAL 1. Remove front engine mount assemblv (if applicable). 2. Remove bolt from center of rotor (Figure 1) and remove washer from bolt. 3. I nstall Tool J-6978-04 and remove rotor assemblv. (Figure 2) I se grease on tapered end of tool. 4. Measure oil seal area with micrometer, for undersize (see Specifications"). a - J-6978-04 Tool Figure 2. Removing Alternator Rotor a - Alternator Rotor b - Center Bolt c - Washer Figure 1. Alternator Rotor 15305 09808 90-95693 485 ENGINE - 6B-27 INSTALLATION ]. Lubricate lip of oil seal and rotor surface (where oil seal rides) with engine oil. 2. Check that rotor locating key is properly installed in crankshaft groove. 3. Lubricate crankshaft end and inside diameter of rotor assembly with Chicago Manufacturing and Distribution Co. anti-scoring, extreme pressure Lubricant No. 3 or equivalent. 4. Position rotor assemblv onto crankshaft, aligning key slot in rotor with kev located on crankshaft. 5. Install Tool J-21058-20 into crankshaft end. Hold tool center shaft from turning and turn large nut to install rotor (Figure 4) until rctor bottoms out. 6. Install rotor fastening bolt and washer and torque boll to specifications. Figure 4. Installation of Alternator Rotor 15230a Figure 3. J-21058-20 Tool STATOR REMOVAL 1. Remove alternator rotor. 2. Disconnect stator wires from regulator. 3. Remove stator fastening screws and remove stator. (Figure 5) INSTALLATION 1. Position stator onto front cover with output w ires toward recess cast in cover. (Figure 5) 2. Applv Loctite "A" on screw threads, install screws and torque to specifications. 3. Reconnect stator wires to regulator. 4. Install alternator rotor. a - Stator Screws b - Stator c - Clamp d - Cover Recess e - Stator Wires Figure 5. Stator Assembly on Engine 6B-28 - ENGINE 90-95693 485 FRONT COVER and CIRCULATING PUMP REMOVAL IMPORTANT: Oil pan gasket must be replaced whenever front cover is removed. 1. Remove front engine mount (if applicable). 2. Remove alternator rotor and stator. 3. Remove parts as shown in Figure 6. (Early 470. refer to 90-95693 485 ENGINE-6B-29 Impeller Impeller Shaft (Left-Hand Thread) Seals IMPORTANT: Support underside of cover when installing oil seals. 2. Both water pump seal lips face water side. First water pump seal is pressed in until it bottoms out: second seal is pressed in until even with cover surface. (Figure 8) a - Nut (Left-Hand Thread) d b - Cupped Washer e c - Shim Washer f • Figure 7. Early 470 Engines CLEANING and INSPECTION 1. Clean all gasket surfaces. 2. Clean parts in solvent and dry with compressed air. 3. Inspect oil seals for wear. Inspect impeller for damage. 4. Inspect surface of shaft where oil seal lips contact shaft. Any groove in shaft in this area requires oil seal and shaft replacement. Engines with impeller screw: Camshaft must he replaced. Engines with impeller nut: Impeller shaft must be replaced. INSTALLATION 1. Applv Loctite "A " to outside diameter of all oil seals. DO NOT allow loctite on lip of seals. a - Tool b - Water Pump Shaft Oil Seals Figure 8. Typical Oil Seal Installation Fill space between water pump oil seals with 2-4-C Multi-Lube. Install crankshaft seal with seal lip toward engine block. Press seal in until it bottoms-out. (Figure 8) 3. Lubricate seal lip with 2-4-C Multi-Lube. 6. Lubricate crankshaft end and water pump shaft w ith 2-4-C Multi-Lube. Using new gasket, install bolts and torque to specifications. Apply Perfect Seal to gasket and bolt tnreads. 8. Install alternator rotor and stator. 9. Reinstall front engine mount. 6B-30-ENGINE 90-95693 485 TIMING CHAIN and SPROCKETS CHECKING TIMING CHAIN DEFLECTION CLEANING and INSPECTION 1. Rotate crankshaft in clockwise direction (as viewed from front) to take up slack on left side of chain. 2. Establish a reference point on cylinder block and measure from this point to chain. 3. Rotate crankshaft in opposite direction to lake up slack on right side of chain. Force left side of chain out with lingers and measure distance between reference point and chain. Deflection is difference between the 2 measurements. If deflection exceeds 1" (25mm), replace timing chain and inspect sprockets and tensioner for abnormal wear. REMOVAL 1. Drain cooling system and crankcase. 2. Remove alternator rotor, slalor and front cover. 3. Crank engine until timing marks on sprockets are positioned as shown in Figure 9. 4. Remove chain tensioner and camshaft sprocket attaching screws. 5. Slide both sprockets and timing chain forward and remove as an assemblv. 1. Clean all parts in solvent and drv with compressed air. 2. Inspect chain. 3. Inspect sprockets for damaged teeth. 4. Inspect chain tensioner for wear. If chain deflection is within specifications and tensioner does not touch chain, replace tensioner. 5. Tensioner. that is worn beyond normal groove wear (Figure 10), must be replaced. 6. Place tensioner on flat surface. Dimension between flat surface and top (highest point) of tensioner must be 1XA" (32mm) or higher. a - Normal Groove Wear b - Excessive Wear Area Figure 10. Chain Tensioner Wear INSTALLATION 1. Position crankshaft locating key and camshaft locating key (or pin) facing as shown in Figure 9. 2. Place timing chain around sprockets and simultaneously install sprockets (with chain) on camshaft and crankshaft, l iming marks must be located as show n in Figure 9. Check timing mark location, using a straight edge. 3. Install camshaft fastening screws and torque to specifications. I. Install chain tensioner. Liberall lubricate chain, chain tensioner and sprockets with engine oil. 5. Install front cover, stator and alternator rotor. 6. Fill cooling system and crankcase to proper levels. a - Timing Marks i b - Sprocket Key c - Sprocket Pin Figure 9. Timing Chain and Sprockets ENGINE - 6B-31 MCM ENGINE COUPLER and/or FLYWHEEL MIE Inboards, refer to "MIE Flywheel Assembly". REMOVAL Flywheel 1. Remove engine from boat. Inspect ring gear for worn. chipped or cracked teeth. If teeth 2. Remove all attaching parts from flywheel housing and are damaged, replace flywheel. remove flywheel housing. 3. Remove coupler. INSTALLATION 4. Remove flywheel. 1. Install flywheel (aligning offset holes) on crankshaft 470R/488R Only: Torque flywheel bolts to specifica- INSPECTION tions. Engine Coupling 2. Install engine coupler. Torque to specifications with torque wrench and Tool (91-35547). 1. Check coupling spline for wear. Coupling wear is caused by 3. Install flywheel housing and housing attaching parts. insufficient lubrication at time of installation. 4. Lubricate coupler splines wit b 2-4-C Multi-Lube and install 2. Inspect hub bond. Bonding, that shears or pulls loose from engine in boat. hub center, indicates engine/drive misalignment. MIE FLYWHEEL ASSEMBLY REMOVAL INSPECTION 1. Make the necessary disconnections, and suspend rear of Inspect flywheel and drive plate for damage. Replace if necesengine to allow removal of transmission and flywheel hous-sary. ing. On some installations it may be necessary to remove engine from boat. INSTALLATION 2. Remove flywheel housing cover plate. 3. Suspend transmission and flywheel housing assemblv in 1. Engines without Weight Kit such a manner that assembly will remain horizontal when a. lnstal. flvwheel and torque to specifications. removed. Remove flywheel housing attaching screws and b. Install drive plate and torque to specifications. washers and slide transmission and flywheel housing as 2. Engines with Weight Kit sembly backward and off engine. a. Install and torque flvwheel as shown in Figure 2. NOTE: One of ike flywheel housing attaching screws is located in cavity over which electrical bracket is installed. 4. Remove drive plate and flywheel. IMPORTANT: Some engines may have Flywheel Weight Kit (251-8478A3) installed. (Figure 1) a - Indexing Dot On Flywheel Aligned with Indexing Line On Crankshaft b - Bolt and Lockwasher (Torque Bolts to Specifications With Loctite Applied to Threads) c - Flywheel Figure 2. Flywheel Installed 1 - Flywheel (251-8478A2) 2 - Drive Plate (97537) 3 - Weight (97513) 4 - Lockwasher (7/16" ID; 13-32993) 5-Screw. Weight and Drive Plate Attaching (7/16"-14x3": 10-97546) Figure 1. Flywheel Weight Kit (251-8478A3) 6B-32 - ENGINE 90-95693 485 b. Apply Loctite "A"' thread locking compound to threads of 6 weight and drive plate attaching screws. Align locating holes in weight with locating pins cn flywheel and install drive plate and weight. (Figures 3 and 4) 15127 a - Align Hole In Weight with Locating Pin on Flywheel (2 Locations) b - Drive Plate c - Weight Figure 3. Installing Weight and Drive Plate a - Torque All Bolts (with Lockwashers) to Specifications Figure 4. Drive Plate and Weight Torque 2. Reinstall transmission and items removed. Torque flvwheel housing and cover to specifications. IMPORTANT: Check alignment as outlined in Section 2, Part I. 470/485 FLYWHEEL RING GEAR (43-97433A1) REPLACEMENT REMOVAL/REPLACEMENT 1. Remove engine from boat. 2. Remove attaching parts from flvwheel housing and remove flywheel housing. 3. Remove and retain flywheel retaining nuts and washers. 4. Remove flywheel and inspect ring gear. 5. Place flywheel so that ring gear can be driven off. 6. Drive ring gear off with drift pin. 7. Place flvwheel so that new ring gear can be installed onto flanged area. 8. Heal ring gear evenly all around Io300° to400°F(149° to 205°Q (DO NOT heal tocherrv red as temper of ring and teeth will be destroved.) a - Flywheel b-Ring Gear Figure 1. Ring Gear Replacement INSTALLATION 1. Position flywheel onto crankshaft studs. 2. Position engine coupler (if so equipped) onto studs and install washers and locknuts. 9. Place healed ring gear onto flywheel, making certain that it 3. Torque to specifications. is seated properly. 4. Install flywheel housing and attaching parts. 10. Allow to cool and check that ring gear has seated rightly. 5. Lubricate coupler (if so equipped) with Quicksilver 2-4-(. Multi-Lube. 6. Reinstall engine. 90-95693 485 ENGINE-6B-33 OIL PAN specifications from center outward in each direction. Re- torque bolts a second time. REMOVAL 1. Drain crankcase oil. 2. Remove oil dipstick and dipstick tube. 3. Remove attaching bolts and washers and remove oil pan. CLEANING and INSPECTION 1. Remove anv dirt or metal particles from inside of pan. 2. Clean gasket surfaces. 3. Wash pan in solvent and dry thoroughly. 4. Check pan for damage. 5. Replace pan if repairs cannot be made. INSTALLATION IMPORTANT: Timing cover must be installed before installation of oil pan. 1. Coat gasket surfaces of block and oil pan with Perfect Seal. Apply sealer thicker in area on block where timing cover meets block and on rear main cap seals. (Figure 1) 2. Position new gasket on cylinder block gasket surface. 3. Position oil pan and install attaching bolts. Torque bolts to a - Rear Main Cap Seals b - Timing Cover Mating Surface Figure 1. Oil Pan Installation 6B-34 - ENGINE 90-95693 485 OIL PUMP REMOVAL 1. Remove oil pan. 2. Remove bolls from oil pump pickup tube clamps. 3. Remove oil pump attaching bolts and remove oil pump assembly. DISASSEMBLY 1. Remove bolts and pickup lube, retaining flange and "0 " ring. 2. Remove screws and lockwasher and remove cover from pump body. 3. Inner and outer rotors each have identification marks on one side. (If there aren't anv marks make 2 as shown in Figure 2.) After installation, these 2 points must appear on the same side. Remove inner and outer rotor. 4. Remove welch plug, spring and valve. CLEANING and INSPECTION 1. Vi ash all parts in solvent. Clean inside of pump housing and pressure relief valve chamber. Be sure that all dirt and metal particles are removed. Drv parts thoroughly with compressed air. 2. Check inside of pump housing, outer rotor and inner rotor for damage or excessive wear. 3. Replace cover if rotor mating surface on cover is damaged. 4. Measure outer race to housing clearance, .001" to .0125" (,02mm to .3mm). (Figure 2) 5. ith rotor assemblv installed in pump housing, place a straight edge over rotor assembly and pump body. (Figure 3) Measure clearance (rotor end plav) between straight edge and rotor. .001" to .005" (,02mm to ,1mm). 6. Check drive shaft to pump housing clearance by measuring Of) of shaft and ID of housing cavity. .0015" lo .0025" (,0381mm to ,0635mm). 7. Inspect relief valve piston for scores and free operation in bore. 8. Inspect relief valve spring for collapsed or damaged condition. a - Feeler Gauge c - Outer Race b - Housing d - Identification Marks Figure 2. Checking Outer Rotor to Housing Clearance 06025 90-95693 485 a - Straight Edge b - Fee er Gauge Figure 3. Checking Rotor End Play a - Welch Plug b - Relief Valve Spring c - Relief Valve Plunger d - Pump Housing e - Outer Rotor f - Inner Rotor g - Cover h - Lockwasher i - Screw Figure 4. Oil Pump Assembly ENGINE - 6B-35 REASSEMBLY Oil pump assembly is shown in Figure 4. 1. Oil all parts thoroughly. 2. Install oil pressure relief valve plunger, spring and new welch plug. Plug should be installed flush with pump housing. 3. Install outer and inner rotor and shaft assembly. Be sure that identification mark on outer and inner rotor is facing the same direction. 4. Install cover and torque cover screws to specifications. 5. Position "0 " ring and install pickup tube, its retaining flange (flat surface against pump housing) and fastening bolts. Torque bolts to specifications. INSTALLATION 1. Position oil pump onto cylinder block and loosely install bolts. 2. Install Oil Pump Alignment Tool (91-75691) thru cistributor hole and into oil pump drive. (Figure 5) 3. Torque oil pump bolts to specifications. 4. Fasten oil pump pickup tube to cylinder block in 2 places, using clamps and screws. Torque screws to specifications. 5. Install oil pan. OIL SEAL (REAR MAIN) REMOVAL CLEANING and INSPECTION 1. Clean oil seal cavity in cvlinder block. 1. Remove flywheel. 2. Inspect area on crankshaft (where oil seal rides) for dam2. Pry old oil seal from cylinder block assembly. Take care age. If necessary, clean up crankshaft surface with No. 320 that crankshaft seal surface is not damaged by tool. grit polishing cloth and engine oil. Replace crankshaft if damage is too great. 3. DO NOT reinstall used seals. INSTALLATION IMPORTANT: Rear main bearing cap must be properly installed before installation of oil seal. 1. Apply Perfect Seal to rear oil seal housing. Sealant must not be applied on crankshaft seal surface. 2. Lubricate oil seal lip and crank surface with engine oil. 3. Drive seal (with lip facing inward) into cvlinder block cavity until it bottoms-out. (Figure 6) I se Tool J-26817. Take care not to cock seal during installation. 90-95693 485 a - 91-75691 Tool b - Torque Pump Bolts c - Oil Pump Figure 5. Installing Oil Pump Assembly a-Mallet b - J-26817 Tool Figure 6. Installing Rear Main Oil Seal 6B-36- ENGINE CAMSHAFT REMOVAL 1. Remove valve lifters. 2. Remove front cover. 3. Remove fuel pump. 4. Mign timing gear marks, then remove timing chain and sprockets. 5. Pull camshaft out thru front of block. IMPORTANT: Support camshaft carefully when removing to protect camshaft bearing surface. INSPECTION 1. Measure camshaft bearing journals with a micrometer for out-of-round condition. If journals exceed specifications, replace camshaf t. 2. Check camshaft for alignment with "\" blocks and dial indicator (Figure 1) for exact amount that camshaft is out-of-true. If out more than .002" (.051mm). replace camshaft. 3. Inspect camshafl sprocket and thrust plate for wear or damage. I. Check all camshafl lobes with dial indicator. (Figure 1) If not within specifications, replace camshaft. 01689 a - Dial Indicator b - "V" Blocks Figure 1. Checking Camshaft a - Dial Indicator b - Indicator Registering Point c - Camshaft Sprocket Figure 2. Checking Camshaft End Play INSTALLATION CAMSHAFT IDENTIFICATION Model Paint Color Near Dist. Drive Gear MC M 470 (5195053 and below) None MC M 470 (5195054 and above) MIE 470 L.H. (Note 1) None MIE 470 R.H. Red MCM 485 ... , .. (466-7553) (N ° t 6 1 ) Green MCM 485 ... . .. (466-8330) (N ° te1 ) Orange MCM 470R/488R Blue or Pink \ OTE 1: H hen ordering ti replacement camshaft, the 470 and 485 camshaft uill be superceded bv >> i ii c cc o oo a> a>a> C CC O OO c cc co 2 Productio ProductioProductio r rr No. 1,2, 3, 4 .0013-.0025 (.0330 . 0635) No. 5 .0024 -.0040 (.0610 . 1016) Service No. 1 .001 -.0015 (.03) No. 2, 3, 4 .001 -.0025 (.03 -.06) No. 5 .00250035 (.07 -.08) Crankshaft End Play .006-.010 (.15-25) •o o cr O) Q QQ ) )) « «« I II I II Diameter 2.1985 2.1995 (55.8419 55.8673) Tape TapeTape r rr Production .0005 (.0127) Max. Service .001 (.025) Max. Out of Round Production .0005 (.0127) Max. Service .001 (.025) Max. Rod Bearing Clearance Production .0009 . 0025 (.0229 . 0635) Service .003 (.07) Max. Rod Side Clearance .013023 (.35 . 55) Crankshaft Runout .0015 (.0381) Max. 6C-16 -ENGINE 90-95693 485 Engin EnginEngin e ee 400 Cyclone 440 Cyclone 460 Cyclone 475 Turbo Camshaft and Drive: Lob LobLob e ee Lif LifLif t tt ± ±± .00 .00.00 2 22 (.051 (.051(.051 ) )) Intake .312 (7.925) .323 (8.204) .294 (7.468) Exhaust .324 (8.230) .328 (8.331) .294 (7.468) Journal Diameter 1.9482 1.9492 (49.484 -49.510) Journal Out-of-Round .001 (.025) Max. Camshaft Runout .002 (.051) Max. Timing Chain Deflection [L.H. (Standard) Rotation Engines Only] 3/8 (10) From Taut Position [3/4 (19) Total] Cylinder Head: Gasket Surface Flatness .003 (.07) in 6 (152) .007 (.15) Overall Maximum Flywheel: Runout .008 (.203) Max. 90-95693 485 ENGINE -6C-17 Engin EnginEngin e ee 400 Cyclone 440 Cyclone 460 Cyclone 475 Turbo Valve System: Lifter Type Hydraulic Rocker Arm Ratio 1.70 to 1 Valve Lash (Intake & Exhaust) Roller rocker arms see page 6C-42 Face Angle (Intake & Exhaust) 45° Seat Angle (Intake & Exhaust) 46° Seat Runout (Intake & Exhaust) .002 (.051) Max. Sea SeaSea t tt Widt WidtWidt h hh Intake 1/32 1/ 16 (.79-1.59) Exhaust 1/16-3/3 2 (1.59-2.38) Ste SteSteSteSte m mmmm Clear ClearClearClearClear - ---anc ancancancanc e eeee Productio ProductioProductio n nn Intake .001 . 0027 (.0254 . 0686) Exhaust .0012 . 0029 (.0305 . 0737) Servic ServicServic e ee Intake .0037 (.0939) Exhaust .0049 (.1244) Engine 400 Cyclone 440 Cyclone 460 Cyclone 475 Turbo Valve Spring: Valv ValvValvValvValvValvValvValvValv e eeeeeeee Sprin SprinSprinSprinSprinSprinSprinSprinSprin g gggggggg Sprin SprinSprinSprinSprinSprinSprinSprinSprin g gggggggg 24-6207 24-620724-620724-620724-620724-620724-620724-620724-6207 4 44444444 (N (N(N(N(N(N(N(N(N o oooooooo Pain PainPainPainPainPainPainPainPain t tttttttt Stripe StripeStripeStripeStripeStripeStripeStripeStripe ) )))))))) Sprin SprinSprinSprinSprinSprinSprinSprinSprin g gggggggg 24-6928 24-692824-692824-692824-692824-692824-692824-692824-6928 8 88888888 (Whit (Whit(Whit(Whit(Whit(Whit(Whit(Whit(Whit e eeeeeeee an anananananananan d dddddddd Ligh LighLighLighLighLighLighLighLigh t tttttttt Blu BluBluBluBluBluBluBluBlu e eeeeeeee Stripe StripeStripeStripeStripeStripeStripeStripeStripe ) )))))))) Free Length 2.210 [2-13/64] (56.1) Pressur PressurPressur e ee (Not (Not(Not e ee 1 11 ) )) Closed @ 1.875 [1-7/8] (4763) 115 Lbs. Ft. (156 N.m) Open @ 1.375 [1-3/8] (34.92) 340 Lbs. Ft. (461 N.m) Installed Height 1.843 [1-27/32] (46.8) Free Length 2.350 [2-11/32] (59.69) Pressur PressurPressur e ee (Not (Not(Not e ee 2 22 ) )) Closed @ 1.875 [1-7/8] (47.63) 155 Lbs. Ft. (210 N.m) Open @ 1.375 [1-3/8] (34.92) 340 Lbs. Ft. (461 N.m) Installed Height 1.906 [1-29/32] (48.4) NOTE 1: Test spring pressure with inner and outer springs assembled NOTE 2: Test spring pressure with inner and outer springs and damper assembled. 6C-18-ENGINE 90-95693 485 GENERAL Some repairs, thai arc listed in this section, must be completed Lubricate all moving parts (during reassembly) with engine oil. with engine removed from boat. Engine removal depends upon Apply Perfect Seal on threads of and under head of cylinder type of repair and boat design. Place engine on repair stand for head bolts and on threads of all cylinder block external bolts, major repairs. screws and studs. Mode ModeMode l ll No. of Cylinders Cu. In. Displacement MC M 898 V-8 305 (5 Itr) MCM/MIE 228 V- V-V- 8 88 305 (5 Itr) MIE 230 V-8 305 (5 Itr) MIE 255 V-8 350 (5.7 Itr) MCM/MIE 260 V- V-V- 8 88 350 (5.7 Itr) MCM/MIE 330 V- V-V- 8 88 454 (7.4 Itr) MIE 340 V-8 454 (7.4 Itr) MCM 370/ 400TRS V- V-V- 8 88 454 (7.4 Itr) Cubic Inch Displacement (CID) of each MerCruiser model ENGINE IDENTIFICATION The MerCruiser Model can be determined by looking at the LAST TWO LE'ITERS of the engine code stamped into the cylinder block. (Figure 1) This code number is stamped on all MerCruiser Power Packages and replacement partial engines but not replacement cvlinder block assemblies. 11 the engine serial number, and/or model decals are missing, the engine code letters may help in determining the engine model. Following is a list of C.M. engines and their respective code letters. a -Small Block V-8 -Front, Starboard Side. Near Cylinder Head Mating Surfaces b -Large Block V-8 -Front of Engine Just Above Timing Gear/ Chain Cover Figure 2. G.M. Engine Code Location ^L a -Engine Code (V06172WT) b -Last Two Letters (WT) 16425 Figure 1. G.M. Engine Code 90-95693 485 ENGINE-6C-19 MCM Stern Drive Engines (All Are L.H. Rotation) 898-MN or MX 330-XS 228-MJ or MY 330 (B-W)-XY 255-WH or WN 370-XF 260-WT MIE Inboard Engines (Either Rotation) L.H. (Standard) Rotation 228-MA 260-WN 230-MA 330-XN or XY 255-WH or WN 340-XY R.H. (Opposite) Rotation 228-MB 260-WR 230-MB 330-XR or XZ 255-WJ or WR 340-XZ CYLINDER HEAD IDENTIFICATION - 305/350 CID Engines (1978-1984) The identification mark is located on both ends of the cylinder head. Figure 4. 350 CID Engines (255, 260) 6C-20- ENGINE 90-95693 485 ENGINE ROTATION Engine rotation terminology at times has caused confusion. To clarify, engine rotation is determined bv observing flywheel rotation from the rear (transmission or stern drive end) of the engine looking forward (water pump end). PROPELLER ROTATION IS NOT NECESSARILY THE SAME as engine rotation. U hen ordering replacement engines, short blocks or parts for engines, be certain to check engine rotation. Do not relv on propeller rotation in determining engine rotation. Taper on lobes coupled with spherical foot on hydraulic valve lifters, causes the valve lifters to rotate, thus reducing wear. A helical gear on theaft end of the camshaft drives the distributor and oil pump, while an eccentric cam on the front of the camshaft actuates the fuel pump. CYLINDER HEAD The cylinder heads are made of cast iron and have individual intake and exhaust ports for each cvlinder. Stainless steel or composition head gaskets are used to retard corrosion. a - Left Hand Rotation (CCW) - All Stern Drive Engines. MIE Inboard L.H (Standard) Rotation b - Right Hand Rotation (CW) - MIE Inboard R.H. (Opposite) Rotation CRANKSHAFT The crankshaft is supported in the block b\ five insert tvpe bearings. Crankshaft end thrust is controlled by flanges on the number five bearing. A torsional damper on the forward end of the crankshaft serves to help dampen anv engine torsional vibration. PISTON and CONNECTING RODS Piston pins are offset slightly toward the thrust side of the pistons to provide a gradual change in thrust pressure against the cylinder wall as the piston travels its path. Pins have a floating fit in the piston and a press fit in the connecting rod (to hold them in place). Connecting rods are made of forged steel and are connected to the crankshaft thru insert tvpe bearings. CAMSHAFT and DRIVE Camshaft is supported bv five bearings, which are pressed into the block, and is driven at one-half crankshaft speed by a timing chain and sprockets or b\ timing gears. VALVE TRAIN The valves and valve springs are of a heavv-dutv design to withstand the high engine speeds encountered. \ a I ve tips have been hardened to extend valve life. Exhaust valve rotators are used on all engines except the (hi-performance 454 CID engines) to help extend valve life. Hydraulic valve lifters ride directly on the camshaft lobes and transmit the thrust of the lobes to the push rods which in turn actuate the valves thru the rocker arm. In addition to transmitting thrust of thecam lobes, the hvdraulic. lifters also serves to remove anv clearance (lash) from the valve train to keep all parts in constant contact. The valve lifters also are used to lubricate the valve train bearing surfaces. INTAKE MANIFOLD The manifold is of the double level design for efficient fuel distribution. The upper level of passages feeds cvlinders 2.3.5 and 8 while ' he lower level passages feed cvlinders 1,4, band All passages are of approximately equal length to assure more even fuel-air mixture to the cvlinders. LUBRICATION SYSTEM The engine lubrication system is of the force-feed type in which oil is supplied under full pressure to the crankshaft, connecting rods, camshaft bearings and valve lifters, and is supplied under controlled volume to the push rods and rocker arms. \11 other moving parts are lubricated b\ gravity flow or splash. A positive displacement gear-type oil pump is mounted on the rear main bearing cap and is driven bv an extension shaft from the distributor (which is driven bv the camshaft). Oil from the bottom of the pump in the rear of the oil pan is drawn into the oil pump through an oil pickup screen and pipe assembly. If screen should become clogged, a relief valve in the screen will open and continue to allow oil to be drawn into system. Once the oil reaches the pump, the pump forces the oil thru the lubrication system. A spring loaded relief valve in the pump limits the maximum pump output pressure. 90-95693 485 ENGINE - 6C-21 After leaving the pump, the pressurized oil flows thru a full- flow oil filter. On engines with an engine oil cooler, the oil also flows thru the cooler before returning to the block. A bypass valve (on all engines except hi-performance 454 CID) allows oil to bvpass the filter and oil cooler should thev become restricted. A bypass \alve is not used on hi-performance 454 CID engines to ensure that all of the oil is filtered. On 305 and 350 CID engines, some of the oil. after leaving the oil cooler and/or filter, is routed lo the No. 5 crankshaft main bearing. The remainder of the oil is routed to the main oil gallery, which is located directly above the camshaft and runs the entire length of the block. From the main oil gallery, the oil is routed thru individual oil passages to an annular groove in each camshafl bearing bore. Some of the oil is then used to lubricate camshaft bearings. The remainder of the oil is routed to the valve lifter oil galleries and No. 1.2, 3. and 4 crankshaft rnai ii bearings bv means of individual oil passages which intersect with the annular grooves. On 454 CID engines, some of the oil.after leaving the oil cooler and/or filter, is routed to the main oil gallery, on the left side of the cylinder block, which supplies oil thru individual passages to the No. 1,2. 3 and 4 crankshaft main bearings and the No. 1. 2, 3 and 4 camshaft bearings. The remainder of the oil is routed to the No. 5 crankshaft main bearing and to an ann ular groove in the No. 5 camshaft bearing bore. Some of the oil is then used lo lubricate the camshaft bearing, while the remainder is routed to both valve lifter oil galleries thru oil passages which intersect the annular groove. The camshaft bearings have holes which align with the oil passages or annular grooves in the block and allow oil to flow in between the bearings and the camshaft journals. The oil that is forced out the front end of the No. 1 camshaft bearing drains down onto camshaft drive and keeps it lubricated. The oil which reaches the crankshaft main bearings is forced thru a hole in the upper half of each bearing and flows in- between the bearings and the crankshaft journals. Some of ihe oil is then routed to the connecting rod bearings thru grooves in the upper half of the crankshaft main bearings and oil passages in crankshaft. Oil which is forced out the ends of the connecting rod bearings and crankshaft main bearings is splashed onto the camshaft, cvlindcr walls, pistons and piston pins, keeping them lubricated. Oil which is forced out the front end of the No. 1 crankshaft main bearing also assists in lubricating the camshaft drive. A baffle plate, mounted on the bottom of the main bearings or in the oil pan, prevents oil thrown from the crankshaft and connecting rods from areating the oil in the oil pan. Oil which reaches the valve lifters oil galleries is forced into each hydraulic valve lifter thru holes in the side of the lifter. From here, the oil is forced thru the metering valve in each ol the lifters (which controls the volume of oil flow) and then up thru the push rods to the rocker arms. A hole in each rocker arm push rod seat allows the oil to pass thru the rocker arm and lubricate the valve train bearing surfaces. After lubricating valve train, oil drains back to the oil pan thru oil returns holes in the cylinder head and block. The distributor shaft and gear also is lubricated by the oil flowing thru the right valve lifter oi! gallery. Fuel pump push rod is lubricated bv oil thrown off from thecamshaft eccentric. BEARING FAILURES 90-95693 485 6C-22- ENGINE PISTON FAILURES PRE-IGNITION Pre-lgnition Causes Pre-ignition is abnormal fuel ignition, caused by combustion chamber hot spots. Control of the start of ignition is lost, as combustion pressure rises too early, causing power loss and rough running. The upward motion of the piston is opposed by the pressure rise. This can result in extensive damage to the internal parts from the high increase in combustion chamber temperature. (Figure 1) 1. Hot spots in the combustion chamber from glowing deposits (due in turn to the use of improper oils and/or fuels!. 2. Overheated spark plug electrodes (improper heat range or defective plug). 3. Any other protuberance in the combustion chamber, such as an overhanging piece of gasket, an improperly seated valve or any other inadequately cooled section of material which can serve as a source. Engine failures, which result from the foregoing conditions, are bevond the control of Mercurv Marine, therefore, no warrants will applv to failures which occur under these conditions. Figure 1. Pre-lgnition Damage 90-95693 485 ENGINE - 6B-23 DETONATION Detonation, common I v called "fuel knock . "spark knock" or "carbon knock", is abnormal combustion of the fuel which causes the fuel to explode violently. The explosion, in turn, causes overheating or damage to the spark plugs, pistons, valves and. in severe cases, results in pre-ignition. (Figure 2) Use of low octane gasoline is one of the most common causes of detonation. Even with high octane gasoline, detonation could occur if engine maintenance is neglected. 3. Cross-firing spark plugs. 4. Excess accumulation of deposits on piston and/or combustion chamber (results in higher compression ratio). 5. Inadequate cooling of engine by deterioration of cooling system. Engine failures, which result from the foregoing conditions, are bevond the control of Mercury Marine, therefore, no warranty will apply to failures which occur under these conditions. Other Causes of Detonation IMPORTANT: Use of improper fuels will cause engine damage and poor performance. 1. Over-advanced ignition timing. 2. Lean fuel mixture at or near full throttle (could be caused by carburetor or leaking intake manifold). Figure 2. Detonation Damage 6B-24 - ENGINE 90-95693 485 FRONT MOUNT - MCM 898/228/260 a - Gasket usea on MCM 898R/228R/260R Engines Only REAR MOUNT/FLYWHEEL HOUSING - MCM 898/228/260 90-95693 485 ENGINE-6C-25 FRONT MOUNT - MCM 330/330 (B-W) 90-95693 485 REAR MOUNT/TAILSTOCK ASSEMBLY - MCM 330 (B-W) 90-95693 485 ENGINE - 6C-27 FLYWHEEL HOUSING - MCM 330 (B-W) 6C-28- ENGINE 90-95693 485 SINGLE ENGINES SIDE BY SIDE ENGINES Note: View of Mount is From Front of Engine, Looking Toward Transom. MOUNTING PLATES - MCM 370/Hi-Performance 454/482 CID Engines 90-95693 1-888 ENGINE - 6C-29 STAGGERED ENGINE (STARBOARD) STAGGERED ENGINE (PORT) Note: View of Mount is From Front of Engine, Looking Toward Transom. MOUNTING PLATES FOR STAGGERED ENGINES - MCM 370/Hi-Performance 454/482 CID Engines 6C-30-ENGINE 90-95693 1-888 FLYWHEEL HOUSING - MCM 370/Hi-Performance 454/482 CID Engines REAR MOUNT/TAILSTOCK ASSEMBLY - MCM 370/Hi-Performance 454/482 CID Engines (Some Models) 90-95693 1-888 ENGINE - 6C-31 FRONT/REAR MOUNTS - MIE 228/230/255/260 In-Line Transmission Engines 6B-32 - ENGINE 90-95693 485 FRONT/REAR MOUNTS - MIE 228/230/255/260 V-Drive Engines 90-95693 485 ENGINE-6C-33 FLYWHEEL HOUSING - MIE 228/230/255/260 Engines NOTE: Center of lower mounting hole is 1/2" (13mm) up from bottom of casting. Front Rubber Insert Cannot Be Removed FRONT/REAR MOUNTS - MIE 330/340 In-Line Transmission Engines 90-95693 485 ENGINE - 6C-35 6C-36-ENGINE 90-95693 485 FLYWHEEL HOUSING - MIE 330/340 Engines 90-95693 485 ENGINE - 6C-37 ROCKER ARM COVER REMOVAL On engines with Center Exhaust Outlet exhaust manifolds: li mav be necessar\ to remove exhaust manifold before removing rocker arm cover. Also remove any component that will interfere with the removal of the manifold or rocker arm cover. 1. Remove rocker arm cover attaching hardware. 2. Disconnect crankcase ventilation hoses. IMPORTANT: DO NOT pry rocker arm cover loose. Gaskets, which adhere to cylinder head and rocker arm cover, may be sheared by bumping end of rocker arm cover from the rear with palm of hand or a rubber mallet. 3. Remove rocker arm cover. INSTALLATION 1. Clean sealing surfaces on cylinder head and rocker arm cover with degreaser. 2. Install rocker arm covers, as follows: Roeker Arm Covers I sing Gaskets: a. Place new rocker arm cover gasket in position in rocker arm cover. b. Install rocker arm cover and secure with reinforcements and attaching screws or nuts. I'orcjue to specifications. Rocker Arm Covers I sing RTN Sealer: a. \pplva3/16" (5mm) wide bead of RTY Sealer all-thewav around sealing surface on cylinder head, making sure :o appl v sealer on inboard side of attaching screw- holes or studs. IMPORTANT: Be sure to install valve rockerarm cover while sealer is still wet. Sealer dries in approximately 15 minutes. b. Install rocker arm cover and secure with attaching screws or nuts. Torque to specifications. 3. Reinstall exhaust manifolds, if removed. 4. Reinstall anv items which were removed from exhaust elbows to allow removal of rocker arm covers. 5. Connect crankcase ventilation hoses to valve rocker arm co\ers. 0. Start engine and check for oil leaks. INTAKE MANIFOLD REMOVAL 1. Drain engine cooling svstem. 2. Disconnect hoses from thermostat housing. On 151 CID engines only: Disconnect intake manifold to circulating pump bv-pass hose from circulating pump. 3. Disconnect wire from water temperature sending unit. On some 454 CID engines, it may be necessary to remove sending unit to allow removal of manifold attaching screw. 4. Disconnect crankcase ventilation hoses from rocker arm covers. 5. Disconnect throttle cable from carburetor. Remove fuel line running between fuel pump and carburetor. On engines with 2-barrel carburetor, also disconnect wires from electric choke. IMPORTANT: DO NOT crank engine over alter distributor has been removed. (). Remove distributor cap and mark position of rotor on distributor housing. Also, mark position of distributor housing on intake manifold. Remove distributor. 7. Remove other ignition components. 8. On 305 and 350 CID engines only: Disconnect wire from oil pressure sending unit and remove sending unit. 9. Disconnect anv other items that will prevent removal of manifold. IMPORTANT: It may be necessary to pry intake manifold away from cylinder heads and block, in next step. Use extreme care to prevent damage to sealing surfaces. 10. Remove intake manifold screws, then remove intake manifold and carburetor assemblv. XOTE: If intake manifold requires replacement, transfer carburetor and other related parts to neit manifold. CLEANING and INSPECTION 1. Clean gasket material from all mating surfaces. IMPORTANT: When cleaning cylinder head mating surface, do not allow gasket material to enter engine crankcase. 2. Inspect manifold for cracks or scratches. Machined surfaces must be clean and free of all marks, or deep scratches or leaks mav result. 3. (Iheck intake passages for varnish buildup or other foreign material. Clean as necessarv. INSTALLATION IMPORTANT: When installing intake manifold gaskets, in next step, be sure to do the following: • On 305 and 350 CID engines: Be sure to install gasket with marked side up. Both gaskets are identical. 6C-38 - ENGINE 90-95693 485 • On 305 CID engines with 2 barrel carburetor: Remove metal insert from manifold gasket to be used on starboard (right) cylinder head to provide clearance for heat pipe on intake manifold. • On 454 CID engines: Be sure to install gasket marked "Right Side Only" on the starboard (right) cylinder head and unmarked gasket on the port (left) cylinder head. • All MerCruiser V-8 G.M. engines that have "automatic" carburetor chokes MUST USE an intake gasket that has an opening for the exhaust crossover port in the intake manifold. (Figure 1) Without this opening the "automatic" choke WILL NOT OPERATE properly. The choke will remain "ON" longer causing rough engine operation and wasted fuel. a - Exhaust Crossover Port Opening in Gasket b - Intake Ports Figure 1. 1. \pplv Perfect Seal lo intake manifold gaskets and in-tall gaskets on cvlinder heads. Install front and rear end seals on cvlinder block and applv Perfect Seal to area- where seals butt against gaskets. IMPORTANT: If cylinder block rails do not have holes for locating pins on end seals, RTV Sealer MUST BE used instead of seals. Place a 3/16" (5mm) wide bead of RTV Sealer. Extend the bead (13mm) up each gasket to seal and retain gaskets. (Figure 2) RTV Sealer can be used instead of end seals on all engines, if desired. a - RTV Sealer b - Intake Manifold Gaskets Figure 2. ENGINE - 6C-39 90-95693 485 2. Careful! v install manifold assembly and torque bolts to specifications in sequence outlined in Figure 3 or 4. 14396 Figure 3. 305/350 CID Manifold Torque Sequence 3. On 454 CID engines only: Connect intake manifold to circulating pump ov-pass hose. 4. Connect wire to water temperature sending unit. 5. Reconnect hoses to thermostat housing. 6. Install fuel line to carburetor and fuel pump. Connect throttle cable to carburetor. On engines with 2-barrel carburetor, also reconnect wires to electric choke. 7. Connect crankcase ventilation hoses to rocker arm covers. 8. Install distributor. Position rotor and housingtoalign with marks made during removal, then install distributor cap. 9. Install other ignition components and reconnect wires. 10. On 305 and 350 CID engines only: Coat threads of oil pressure sending unit with Perfect Seal and install. Connect wire to sending unit. 11. Reconnect any other items which were disconnected from manifold during the removal. 12. Start engine. Adjust ignition timingand carburetor. Check hose connections, gasket.- and seals for leaks. 13. Inspect fuel line connections for fuel leaks. Figure 4. 454 CID Manifold Torque Sequence 6B-40 - ENGINE 90-95693 485 ROCKER ARM/PUSH ROD REMOVAL 1. Remove rocker arm covers. 2. Remove rocker arm components, rocker arms and push rods. IMPORTANT: Place rocker arms, rocker arm components and push rods in a rack for reinstallation in the same locations. CLEANING and INSPECTION 1. Clean parts with solvent and drv with compressed air. 2. Inspect all contact surfaces for wear. Replace all damaged parts. INSTALLATION 305 CID, 350 CID and 454 CID (Without Roller Rocker Arms) Engines: IMPORTANT: Push rods with a hardened tip end MUST BE installed with the hardened tip toward rocker arm. Push rods without hardened tip MUST BE installed with large oil hole end toward rocker arms. Hardened tip end or large hole end is marked with a blue stripe. IMPORTANT: When installing rocker arms and rocker arm balls, coat bearing surfaces of rocker arms and rock arm balls with engine oil. I. Install push rods. Be sure push rods seat in lifter socket. 2 Install rocker arris, rocker arm balls and rocker arm nuts. I igliten rocker arm nuts until all lash is eliminated. 3. \alve lash can be adjusted either with engine slopped or running. 454 CID (With Roller Rocker Arms) Engines: IMPORTANT: No. 1 and No. 8 intake rocker arm have 3/16" (5mm) removed from left hand corner of arm to clear valve cover. If new rocker arm is used, modify as shown in Figure 1. IMPORTANT: When installing rockerarmsand push rods, lubricate with engine oil. GRIND-n OFF ; 3/16" (5mm) Figure 1. No. 1 and No. 8 Intake Rocker Arm 1. Install push rods (long-exhausl. shcrl-inlakel. Be -lire push reds -eat in lifter socket. 2. I iis tall new rocker arms making sure t • ia I flat side ol pi vol shall is facing up. (Figure 2) Lubricate ends of rocker arm studs and valve stem end- with Needle Bearins Lubricant (92-426WA1). In-tall locking mils on studs. 3. \ alve adjustment must be done with engine-topped. FLAT MUST BE UP 90-95693 485 ENGINE -6C-41 ADJUSTMENT - ENGINE STOPPED 305, 350 and 454 (without Roller Rocker Arm) CID Engines: ^ ilh valve cover removed, adjust valves when lifter is on low part of camshaft lobe, as follows: 1. (".rank engine with starter or turn over in normal direction of rotation until mark on torsional damper lines up with center "0 " mark on timing tab. and engine is in No. 1 firing position. This may be determined bv placing lingers on No. 1 valve as mars on damper comes near O mark on timing mark. If valves move as mark comes up to timing tab. engine is in No. 6 firing position and should be turned over one more time to reach No. 1 position. 2. With engine in No. 1 firing position, as determined above, the following valves may be adjusted. gines: Exhaust - 1-3-4-8 Intake - 1-2-5-7 MIE Right Hand (Opposite) Rotation Engines: Exhaust - 1-2-5-7 Intake - 1-3-4-8 4. Back out adjusting nut until lash is felt at push rod. then turn in adjusting nut until all lash is removed. This can be determined by moving push rod up-and-down while turning adjusting nut until all plav is removed. (Figure 3) 14403 5. Hvdraulic lifters now can be adjusted by tightening adjustment nut an additional 1-turn. No other adjustment is required. 6. Crank engine one revolution until pointer ' 0" mark and torsional damper mark are again in alignment. This is No. 6 firing position. ith engine in this position, the following valves mav be adjusted as previously outlined. 7. MCM and MIE Left Hand (Standard) Rotation Engines: Exhaust - 2-5-6-7 I ntake - 3-4-6-8 MIE Right Hand (Opposite) Rotation Engines: Exhaust - 3-4-6-8 Intake - 2-5-6-7 454 (with Roller Rocker Arms) CID Engines: Valves must be adjusted when hydraulic lifter is on low part of camshaft. 1. Rotate engine (in normal direction of rotation) until timing mark on crankshaft balancer lines up with "0" (1 DC) mark on timing tab and engine is in No. 1 firing position. This may be determined by placing fingers on No. 1 push rods as mark on balancer comes near the "0" (TDC) mark. If push rods move as timing mark comes up on 0 . engine is in No. 6 firing position. Rotate crankshaft one more 2. With engine crankshaft positioned as outlined, adjust valves on the following cylinders: Exhaust - 1-3-4-8 Intake - 1-2-5-7 IMPORTANT: Make sure push rods are centered in sockets of rocker arm BEFORE tightening. This must be done for each valve. Figure 3. Valve Adjustment 6C-42 - ENGINE 90-95693 485 3. To obtain corre:t valve lash, turn 9/ 16" locking nut down on rocker arm until there is zero clearance between rocker arm and valve stem. Turn locking nut an additional '/2 turn and snug alien screw onto top of rocker arm stud. DO NO! let locking nut turn. Remove alien wrench and box wrench and torque locking nut to 30 lbs. ft. (41 N.m). (Figure 4) 17736 Figure 4. Valve Adjustment 4. Rotate crankshaft one complete (360°) revolution until timing mark on balancer is aligned with "0 " mark on timing tab. Adjust valves on the following cvlinders: Exhaust - 2-5-6-7 Intake - 3-4-6-8 .">. \djlist remaining rocker arms as outlined in Step 3. 305, 350 and 454 (without Roller Rocker Arms) CID Engines: Following procedure is performed with engine running: 1. \fter engine has reached normal operating temperature, remove valve covers and install rocker stoppers. (Figures) 2. With engine running at idle, back rocker arm nuts off (one at a time) until valve rocker arm starts to clatter. (F igure (>) 3. Turn rocker arm nut down until clatter just stops. I lii- i4. Turn nut down Vt additional turn and pause 10 seconds until engine runs smo'olhlv. Repeal until nut ha> been turned down 1-turn from the zero lash position. ADJUSTMENT - ENGINE RUNNING IMPORTANT: This 1-turn preload adjustment must be done slowly to allow lifter to adjust itself, thus preventing possibility of interference between inlet valve head and top of piston which might result in internal damage and/or bent push rods. 5. Repeal Steps 2-3-4 lo adjust oilier valve-. 6. Remove rocker stopper- after all valves are adjusted. 7. \fler valves have been adju.-ted. complete the following: a. In>tall new gaskest (or R I \ ). and install cover-. Torque to specification-. b. Adjust carburetor idle speed and mixture. c. Start engine and check for leaks. Figure 5. Rocker Stoppers 91-66273 14404 90-95693 485 ENGINE - 6B-43 HYDRAULIC VALVE LIFTERS a - Lifter Body b - Plunger Spring c - Check Ball Retainer d - Check Ball Spring e - Check Ball f - Plunger g - Metering Valve h - Push Rod Seat i - Push Rod Seat Retainer Figure 1. Hydraulic Valve Lifter Assembly Hvdraulic valve lifters require little attention. Lifters are extremely simple in design. Normally, readjustments are not necessary and servicing requires onlv that care and cleanliness be exercised in the handling of parts. LOCATING NOISY LIFTERS Locate a noisy valve lifter by using a piece of garden hose approximately 4 ft. (1.2m) in length. Place one end of hose near end of each intake and exhaust valve, with other end of hose to the ear. In th;s manner, sound is localized, making it easv to determine which lifter is al fault. Another method is to place a finger on face of valve spring retainer. If lifter is not functioning properlv. a distinct shock will be felt when valve returns to its seat. General tvpes of valve lifter noise are as follows: 1. Hard rapping noise - I sually caused by plunger becoming tight in bore of lifter bodv so that return spring cannolpush plunger back up to working position. Probable causes are: a. Excessive varnish or carbon deposit, causingabnormal stickiness. b. Galling or "pick-up" between plunger and bore of lifter body, usually caused by an abrasive piece of dirt or melal wedged between plunger and lifter body. 2. Moderate rapping noise -- Probable causes are: a. Excessively high leakdown rate. b. Leaky check valve seat. c. Improper adjustment. 3. General noise throughout valve train -- This will, in most cases, be a definite indication of insufficient oil supply or improper adjustment. 4. Intermittent clicking -- Probable causes are: a. A microscopic piece of dirt momentarily caught between ball seal and check valve ball. b. In rare cases, ball itself may be out-of-round or have a flat spot. c. Improper adjustment. In most cases, where noise exists in one or more lifters, all lifter units should be removed, disassembled, cleaned in solvent, reassembled and reinstalled in engine. If dirt, corrosion, carbon, etc, is shown to exist in one unit. :t more likely exists in all the units, thus it would only be a matter of time before all lifters caused trouble. REMOVAL 1. Remove intake manifold. 2. Remove valve mechanism. 3. Remove valve lifters. IMPORTANT: Keep push rod and hydraulic valve lifter from each valve together as a matched set and mark them so they can be reinstalled in the same location later. DISASSEMBLY !\'OTE: Refer to Figure 1, for parts identification. IMPORTANT: The internal parts of each hydraulic lifter assembly are matched sets. DO NOT INTERMIX the PARTS. \ Hold plunger down with a push rod and remove push rod seat retainer with the blade of a small screwdriver. 2. Remove push rod seat and metering valve. 7B-44 - COOLING SYSTEM 90-95693 485 3. Remove the plunger, ball check valve assemblv and the plunger spring. 4. Remove the ball check valve and spring by prving the ball retainer loose from the plunger with the blade ofa small screwdriver. (Figure 2) 14406 a - Check Ball Retainer Figure 2. Removing Ball Check Valve CLEANING and INSPECTION Thoroughly clean all parts in cleaning solvent and inspect them careful!v. If anv parts are damaged or worn, entire lifter assemblv should be replaced. If outer lifter bodv wall is scuffed or worn, inspect cvlinder block lifter bore. If bottom ol lifter is scuffed or worn, inspect camshaft lobe. II push rod seat is scuffed or worn, inspect push rod. REASSEMBLY 1. Place the check ball in small hole in hot torn of tic plunger. 2. Insert check ball spring on seat in ball retainer and place retaitier over ball so that spring rests on the ball. (!arefullv press the retainer into position in plunger with I lie blade of a small screwdriver. (Figure 3) a - 1/8" Drift Pin b - Oil Feed Hole c - 1/16" Drift Pin Figure 4. Oil Feed Holes Aligned and Dritt Pin Installed 14407 a - Check Bal! Retainer Figure 3. Installing Check Ball Valve 3. Place tlie plunger spring over the hall retainer and slide the lifter body over the spring and plunger, being careful to line up the oil feed hole in the lifter bodv and plunger. 1. Fill theassemblv with oil. then insert the end ofa Vs" drift pin into the plunger and press down on check ball until hole in lifter bodv aligns with hole in plunger. 5. Insert ^ 1/ 16" drift pin through both oil holes to hold the plunger down against the lifter spring tension. (Figure 4) 14408 90-95693 485 ENGINE-6C-45 VALVE STEM OIL SEAL/VALVE SPRING Review "Cylinder Head Assemblies" BEFORE starting repair. IMPORTANT: DO NOT attempt to force or pump the plunger. 6. Remove the Va" drift pin and refill assemblv with oil. 7. Install the metering valve, push rod seal and push rod seal retainer. 8. Press down on the push rod seat with a push rod and remove 1/16" drift pin from lifter. The lifter is now completely assembled, filled with oil and ready for installation. INSTALLATION IMPORTANT: Before installing lifters, coat the bot- REMOVAL 1. Remove rocker arm cover. 2. Remove spark plug, rocker arm and push rod on cylinder^) to be serv iced. 3. Position piston (in cylinder to be serviced) at TDC. to prevent valve from dropping out of valve guide. 4. Compress valve spring with J-5892 Tool. Remove valve locks and all other components. (Figure 1) 14419 a - J-5892 Tool b - Rocker Arm Nut Figure 1. Compressing Valve Spring 5. Remove valve stem oil seal(s) from valve (except later stvle 454cu. in. hi-performance engines). V OT!:: On later style 454 CID hi-performance engines, valve stem oil seal is part of valve cap. If oil seal requires replace ment. entire valve cap and seal assembly ML ST HI' replaced. torn of the lifter with engine oil. If new litters or a new camshaft has been installed, an additive containing EP lube (such as Quicksilver 4-Cycle Super Engine Oil Supplement) should be poured over camshaft lobes before installing lifters. 1. Install hydraulic valve lifters. 2. Install intake manifold. 3. Install and adjust valve mechanism as outlined. 4. Install rocker arm cover. 5. Start engine and check for leaks. INSTALLATION 305/350 CID Engines: 1. If removed, install damper in valve spring. 2. If engine has additional valve stem seal: a. Install intake valve seal. b. DO NOT install exhaust valve seal, discard. 3. Set valve spring, damper, valve shield and cap in place. Be sure to install valve cap with rotator on exhaust valve. Compress spring with Tool J-5892 and install oil seal into lower groove ol valve stem. \ OT /•. I light film of oil trill help prevent lu-isting of the seal. 4. Install valve locks and release pressure of tool, being sure that locks are in place. Crease mav be used to help hold locks while removing pressure from tool. 454 CID Engine - Standard and Earlier Style Hi-Performance: 1. Install valve rotator or shim in position on valve spring seat. (Rotator is used on exhaust valve; shim is used on intake valve.) 2. Coal valve stem oil seal with engine oil and install over valve stem. IMPORTANT: If new pressed-on type intake valve stem oil seals are to be used, install seals in accordance with instructions which accompany them. 3. If removed, install damper in valve spring. 4. Set valve springand damper assembly and valve spring cap in position over valve stem. 5. Compress spring with J-5892 tool and install valve locks. Then release compressor tool, making sure that locks seat properly in groove of valve stem. NOTE: Grease may be used to hold locks in place while releasing compressor tool. IMPORTANT: Compress valve spring only enough to install valve locks in next step. Excess compression could cause valve spring cap to damage seal. 6C-46 - ENGINE 90-95693 485 454 CID Engines - Later Style Hi-Performance: 1. Make sure thai shim is in position on valve spring seat. 2. Set valve springsand damper assemblv and valve springcap and oil seal assemblv in position over valve stem. 3. Compress spring vvilli J-5892 tool and install valve locks. Then release compressor tool, making sure thai locks scat properlv in groove ol valve stem. \OTE: Grease ma\ be used lo hold locks in place while releasing compressor tool. IMPORTANT: Compress valve spring only enough to install valve locks in next step. Excess compres sion could cause damage to seal. 305/350/454 CID Engines: 1. Install spark plug(s) and torque to specifications. 2. Install and adjust valve mechanism. 3. Install rocker arm cover and lorque lo specifications. 4. Start engine and check for leaks. CYLINDER HEAD ASSEMBLIES REPLACEMENT PART INFORMATION 305/ 350 CID ENGINES IMPORTANT: Be sure to read this information before performing any repairs on cylinder head, exhaust valve springs and/or exhaust valve. Three different types of cvlinder heads are in use on Mer- Cruiser 305 and 350 CI I) Engines: 11) The heavv head. (2) the lightweight - 1st design head and (3) the lightweight - 2nd design head. The new lightweighc cvlinder heads were released for 1978 production 305 and 350 (.11) engines. These new heads are approximately 6 pounds lighter than the earlier stvle heavv heads. The lighI weight heads were used together with the earlier si vie heavv heads for a period ol time, because of production requirements and limited machining capacities at the manufacturer's casting and machining plants. I herefore. engines may be assembled with either heavv or lightweight heads or one of each l vpe. Heavy and Lightweight Head Identification: To determine if a head i-a heavv head or a lightweight head, refer to Figures l and 2. a - Straight Bottom Surface Design Contour b - Round Water Passage Holes Figure 1. Heavy Head Identification a - Irregular Bottom Surface Design Contour b - Fan-Shaped Water Passage Holes Figure 2. Lightweight Head Identification Lightweight Head - 1st Design: hxhaust valve spring scats are machined to "heavv" head specifications (uses 24-48347 valve spring assemblv for intake valv e and 24-72642 valve spring assemblv lor exhaust valve). Lightweight Head - 2nd Design: Incorporates machining lhal allows intake v alve spring assemblv (24-48347) lo be used at both intake and exhaust valve locations. The valve springs can be identified bv paint stripes and measurements. as follows: • 24-48347 Intake Spring: (one lavender stripe) approx. 2.03" I2-1/32" (51.5mm) | free height • 24-72612 • hxhaust Spring: (2 light green stripes) approx. 1.91" |l-29/32" (48.5mm)| free height I he cvIirider heads can be identified bv measuring from the top of the exhaust valve guide to valve spring seat. (Figures 3 and 4) Service cvlinder heads must In- identified bv this method to ensure correct valve spring usage prior lo installation. 90-95693 485 ENGINE - 6C-47 a - .75" [3/4" (19mm)] Figure 3. 1st Design Lightweight Head, Use 24-72642 Valve Spring Exhaust Valve Stem Diameter/Guide Bore: All earlv style "heavy" cylinder heads have exhaust valve guide bores machined to accept .341" (8.661mm) exhausl valve stems. (Exhaust valve 35323). l-ale slvle ' lightweight"' cvlinder heads were manufactured with both .341" (8.661mm) and .372" (9.449mm) exhaust valve stem diameters. MCM 898 models with "lightweight" cylinder heads use exhaust valves with .341" (8.661mm) stem diameter (85803). MCM/MIE 228. MIE 255 and MCM 260 models with "lightweight" cvlinder heads normally use exhaust valves with .372" (9.449mm) stem diameter (87284): HOWEVER, there have been instances where small diameter .341" (8.661 mm) exhausl valve (85803; stems and guide bores have been found in these models. It is imperative, therefore, lhal precise measurements of exhaust valve stem/guide dimensions be taken when ordering replacement exhaust valves for these models. Cylinder Heads with Valve Guide Seal: Later production, lightweight heads - 2nd design: W ith valve guide seals, refer to Figures 5 and 6. IMPORTANT: DO NOT use exhaust valve guide seals. If engine has seal, remove and discard during repair. a - .84" [27/32" (21mm)] Figure 4. 2nd Design Lightweight Head, Use 24-48347 Valve Spring a - Valve Guides Figure 5. Machined Valve Guides 6C-48 - ENGINE 90-95693 485 17752 a - Intake Valve Guide Seals b - Exhaust Valve Guide Seals - Discard Figure 6. Valve Guide Seals Replacement Cylinder Heads: \X hen ordering replacement cylinder heads, determine if early slvle "hcavv" or late stvle lightweight" cvlinder heads are required, then order From the following chart: MODEL "HEAVY" "LIGHTWEIGHT" MCM 898 MCM/MIE 228 MCM 26C/MIE 255 938-6536 938-6536 938-4625 938-7482 938-7482 938-7499 MCM 898R/228R/ 0 , , n t ,, . „„ „ Refer to Parts Manual MIE 230/260 Refer to Parts Manual All light weight" service replacement cvlinder heads are 2nd design configuration: therefore, ifa replacement cvlinder head is required for an engine, that is originallv equipped with a 1st design lightweight" cvlinder head, new exhaust valve springs (24-48347) also must be installed (4 required per cvlinder head). In addition, all "lightweight" service replacement cvlinder heads use exhaust valves with .372" (9.449mm) stem diameter. Because of this, when installing a replacement "lightweight" cylinder head on a MCM 898. new exhaust valves (87284) also must be installed. Anv model MerCruiser \ -8 engine, which was originallv equipped with an earlv style "heavv" cvlinder head, can be converted to late stvle lightweight cvlinder head onlv if the proper exhaust valves and exhaust valve springs also are installed. CYLINDER HEAD Review "Cylinder Head Assemblies" BEFORE Starting Repair REMOVAL 1. Drain engine cooling svstem. 2. Remove exhaust manifolds. 3. Remove intake manifold. I. Remove valve mechanism. \ Oil.: Remote an v component attached to front or aft end of cylinder head to be removed. 5. Remove spark plugs. 6. Remove spark plug wire retainers from cylinder head. 7. Remove cvlinder head bolts, cylinder head and gasket. 8. Place cvlinder head on 2 blocks of wood to prevent damage. CLEANING and INSPECTION I or cleaning and inspection, refer to Cvlinder Head and \ al ve Conditioning". INSTALLATION I. On engines using a STAINLESS STEEL gasket, coat both sides of new gasket with Perfect Seal. Spread sealer thin and even. Too much sealer mav hold gasket awav from head or block. 90-95693 485 ENGINE-6C-49 2. Place gasket in position over dowel pins. 3. Carefully guide cylinder head into place over dowel pins and gasket. 4. Coat threads of cylinder head bolts with Perfect Seal and install bolts finger-tight. 5. Tighten each cylinder head bolt a little at a time in sequence shown in torque sequence chart until specified torque is reached. (Figure 1 or 2) 6. Install exhaust manifolds as outlined. 7. Install intake manifold as described. 8. Install and adjust valve mechanism as outlined. 9. Install valve covers. 10. Install spark plugs. Torque spark plugs to specifications. 11. Install spark plug wire retainers. Figure 1. Cylinder Head Torque Sequence 305/ 350 CID Models MOTE: Install any component that was removed from thefronl or aft end of cylinder head. 12. Run engine, adjust timing and check for leaks. Figure 2. Cylinder Head Torque Sequence - 454 CID Models CYLINDER HEAD and VALVE CONDITIONING Review "Cylinder Head Assemblies" BEFORE Starting Repair. DISASSEMBLY CLEANING 1. With cylinder head removed, remove rocker arms and 1. Clean all carbon from combustion chambers and vale components (if not previously done). ports with J-8089 tool. (Figure 2) 2. Compress valve springs with J-8062 tool (Figure 1) and remove valve retainers. Release compressor tool and remove all valve components. 3. Remove valves from cylinder head and place valves in a rack in their proper sequence lor reassembly in their original positions. a - J-8089 Tool Figure 2. Cleaning Combustion Chambers 2. Thoroughly clean valveguides with J-8101 tool. (Figure3) 3. Clean all push rods, rocker arms and push rod guides. 4. Clean carbon from valves on a buffing wheel. 5. Clean carbon deposits and gasket material from cvlinder head mating surfaces. 14424 7A-50- COOLING SYSTEM 90-95693 485 IMPORTANT: Cylinder head to block gasket surface should be resurfaced if out-of-flat more than specified. When resurfacing gasket surface, cylinder head to intake manifold gasket surface also MUST BE milled to provide proper alignment between manifold and head. 3. Inspect valves for burned heads, cracked laces or damaged stems. IMPORTANT: Excessive valve stem to bore clearance will cause excessive oil consumption and possible valve breakage. Insufficient clearance will result in noisy and sticky functioning of valve and disturb engine smoothness. 4. Measure valve stem clearance (Figure 5) as follows: Clamp a dial indicator on one side of cvlinder head rocker arm cover gaskel rail, locating indicator so lhal movement of valve stem from side-lo-side (crosswise lo the head) will cause a direct movement ol indicator stern. Indicator stem a - J-8101 Tool must contact side of valve stem just above valve guide. Figure 3. Cleaning Valve Guides Willi valve head dropped about 1/16" (2mm) off valve seal, move valve stem from side-to-sice, using light pres- INSPECTION sure to obtain a clearance reading. If clearance exceeds specifications, il will be necessarv to ream valve guides for oversize valves, as outlined under \ alve Guide More combustion chambers (especially around spark plug holes 1. Inspect cylinder head for cracks in the exhaust ports, Repair". and valve seals) and for cracks in external surface of water jacket. Replace head if cracked. 2. Inspect cylinder head gasket surface for burrs, nicks, erosion or other damage. Also, check flatness of cvlinder head gaskel surface, using a machinists straight edge and feeler gauges as shown in Figure 4. Refer to "Specifications". Figure 5. Measuring Valve Stem Clearance 5. Check valve spring tension w il h J-80f>(: spring tester, (figure 6) 14426 14427 a - Straight Edge b - Feeler Gauge c Take Measurements Diagonally Across Head (Both Ways) and Straight Down Center Head IMPORTANT: Springs should be compressed to specified height and checked against specification. Springs should be replaced if not within 10 lbs. ft. (13.5 N.m) of specified load. Figure 4. Checking Gasket Surface of Cylinder Head 6. Inspect rocker arm sluds for wear or damage. Inspect push for Flatness rod guides lor wear or damage. 90-95693 485 ENGINE - 6C-51 2. l.se Tool J-5802-01 to remove old stud bv placing tool, flat washer and nut over stud, then turning nut. (Figures 7 and 8) 3. Ream stud hole, whenever installing ail oversize stud, using appropriate reaming tool. 4. Install new stud with Tool J-6880 or similar stud installing tool made for press-in tvpe studs. (Figure 9) Follow instructions with tool. 14429 Figure 6. Checking Valve Spring Tension ROCKER ARM STUDS and PUSH ROD GUIDE REPAIRS 305/350 CID Models: 1. Rocker arm studs, which are replaced because of wear or looseness, should be replaced with oversize studs. 14420 a - Install Small Sleeve b - Turn Nut to Remove Stuc Figure 8. Removing Stud a - Large Sleeve b - 3/8 x 24 Nut - Turn until Nut Bottoms Out on Stud Tireads, Then Remove Nut Figure 7. Using J-5802-01 Tool Figure 9. Installing Stud Tool J-6880 7A-52 - COOLING SYSTEM 90-95693 485 454 CID Models: IMPORTANT: Rocker arm studs are threaded into the cylinder head. Coat threads on cylinder head end of rocker arm studs with sealer before assembling to cylinder head. Hush rod guides are attached lo cvlinder head bv rocker arm studs. (Figure 10) Replace if worn and torque rockerarm studs to specifications. 14411 Figure 10. 454 Cylinder Head VALVE GUIDE BORE REPAIR IMPORTANT: On 305 and 350 CID engines, be sure to measure valve stem diameter of both the intake and exhaust valve, as valve stem diameter may or may not be the same for both valves. If .015" oversize valves are required ream valve guide bores for oversize valves, as follows: 1. Measure valve stem diameter of old valve being replaced and select proper size \alve Guide Reamer from chart below. Standard Valve Stem Diameter Reamer Required for Oversize Valve .341 J-5830-2 .372 J-7049-5 2. Ream valve guide bores, as shown in Figure 11. 3. Remove the sharp corner created bv reamer at topof valve guide. Figure 11. Reaming Valve Guides VALVE SEAT REPAIR \alve seat reconditioning is very important, since seating of valves must be perfect for engine to deliver maximum power and performance. Another important factor is valve head cooling. Good contact between each valve and its seat in head is important to insure that heat in valve head will be properlv dispersed. Several different t \ pes of equipment are available for reseating valve scats Equipment manufacturer s recommendations should be followed carefullv to attain proper results. Regardless of type of equipment, however, it is essential that valve guide :>ores be free from carbon or dirt to insure proper centering of pilot iti valve guide. 1. Install expanding pilot in valve guide bore and expand pilot. 2. Place roughing stone or forming stone over pilot and clean up valve seat onlv. I sea stone that iscut to specifications. 3. Remove roughing stone or forming stone from pilot, place finishing stone (cut to specifications) over pilot and cut just enough metal from seat to provide a smooth finish. Refer to Specifications'" and Figure 12. 4. Narrow down valve seats to specified width by grinding with a 30° stone to lower seat and a 60° stone to raise seat. 90-95693 485 ENGINE - 6C-53 a - Top Edge "Approach Angle" (30°) b - Seat Angle c - Seat Width d - Bottom Edge (60°) Figure 12. Valve Seat in Cylinder Head 5. Remove expanding pilot and clean cylinder head carefully to remove all chips and grindings from above operations. 6. Measure valve sea: width. See "Specifications". 7. Measure valve seat '"out-of-round". (Figure 13) See "Specifications". 05024 Figure 13. Measuring Valve Seat Concentricity Figure 14. Critical Valve Dimensions VALVE REPAIR Pitted valves can be refaced to properangle on a valve grinder, thus insuring correct relation between cvlinder head seat and valve mating surface. Replace valves with excessive wear on stems or valves which are warped excessively. When an excessively-warped valve head is refaced, a knife edge will be ground on part or all of the valve head, due to amount of metal that must be removed to completely reface. Knife edges lead to breakage, burning or pre-ignition caused by heat localizing in this knife edge. If edge of valve head is less than 1/32" (.8mm) thick after grinding, replace the valve. Various equipment is available for refacing valves. Manufacturer's recommendations should be carefully followed to attain proper results. 1. If necessary, dress the valve refacing machine grinding wheel to make sure it is smooth and true. Set chuck at angle specified for valve. Refer to "Specifications". 2. Continue grinding until valve face is true and smooth all around the valve. If this makes valve head thin [1/32" (.8mm) minimum], valve must be replaced, or valve will overheat and burn. (Figure 14) 3. Remove valve from chuck and place stem in "V " block. Feed valve squarely against grinding wheel togrind any pit from rocker arm end of stem. IMPORTANT: Only extreme end of valve stem is hardened to resist wear. Do not grind end of stem excessively. 4. After cleaning valve face and cylinder head valve seat of grinding particles, make pencil marks about V*" (6mm) across the valve face, place valve in cylinder head and give valve '/2-turn in each direction while exerting firm pressure on head of valve. 5. Remove valve and check face carefully. If all pencil marks have not been removed at point of contact with valve seat, repeat refacing operation and again recheck for proper seating. 6C-54- ENGINE 90-95693 485 REASSEMBLY • Lubricate valve guides and valve stems with engine oil. • Install each valve in the port from which it was removed or to which it was fitted. • Install valve stem oil seal, valve spring(s) and related parts on each valve as explained under "Valve Stem Oil Seal and/or Valve Spring". • Compress valve spring with Tool J-8062. • Check installed height of the valve springs with a narrow, thin scale. A cutaway scale will help. (Figure 15) Measure from top of spacer (spring seat) to top of valve spring. (Figure 16) If this exceeds specified height, install a valve spring seat shim approximately 1/16" (1.6mm) thick. At no time should spring be shimmed to give an installed height under minimum specified. SEE SPECIFICATIONS Figure 16. Measuring Valve Spring Installed Height Figure 15. Cutaway Scale OIL PAN REMOVAL 1. Drain coolant. 2. Drain crankcase oil. 3. Remove oil dipstick and tube, il required. 4. Remove oil pan and discard gaskets. 305/350 CID ENGINE OIL PAN REPLACEMENT INFORMATION Karl v c\ linder blocks had the oil dipstick tube mounting hole on the port (left) side. Liter cvlinder blocks had the mounting hole on the starboard (right) side. IMPORTANT: MIE engines normally have mounting hole plugged, however, this information applies to those engines also. b - Starboard Side Figure 1. Oil Dipstick Tube Mounting Sides 90-95693 485 Port Side Mounting Hole: Earlv MCM 898. 228. 260 and VIIK 228. 255 engines. Starboard Side Mounting Hole: Uler MC.V1 898. 228. 260 and MIK 228. 255 engines. \ll V1CVI 898R, 228R. 260R and VIIK 230. 260 engines. IMPORTANT: Engines with Center Exhaust Outlet on exhaust manifold must use starboard side mounting hole cylinder blocks. Oil Pan Baffle MCM »98 engine: Baffle is part of oil pan. All other engines: Determine which side ol engine oil dipstick tube mounting hole is on and use appropriate one. Refer to Parts Manual. Oil Pan Determine which side of engine oil dipstick tube mounting hole is on and use appropriate one. Refer to Parts Manual. Oil Pan Gasket Determine which side of engine oil dipstick tube mounting hole is on and use appropriate one. Refer :o Parts Manual. Oil Dipstick and Tubes Refer to Parts Manual for part numbers, then refer to Figures 2, 3. 4. 5 or 6. ENGINE-6C-55 a - 72950 - Lower Tube b - 32-72539 - Upper Tube c - 77454 - Dipstick (MCM 898) d - 72938 - Dipstick (MCM 228, 260) Used on: MCM 898 - S/N 5496181 and below MCM 228 - S/N 5229542 and below MCM 260 - S/N 5246183 and below Figure 2. MCM Engines, Port Mounted Dipstick 7A-56 - COOLING SYSTEM 90-95693 485 a - 86085 - Lower Tube b - 86083A1 - Upper Tube c - 86082 - Dipstick Used on: MCM 228 - S/N 5229543-5515813 MCM 260 - S/N 5246184-5500136 Figure 3. MCM Engines, Port Mounted Dipstick 90-95693 485 ENGINE-6C-57 a - 92078A1 - Tube b - 73232 - Dipstick (MCM 898) c - 86082 - Dipstick (MCM 228, 260) Used on: MCM 898 - S/N 5496182-6218461 MCM 228 - S/N 5515814-6225266 MCM 260 - S/N 5500137-6227756 Figure 4. MCM Engines, Starboard Mounted Dipstick 6C-58-ENGINE 90-95693 485 a - 92163A2 - Tube b - 96822A1 - Dipstick (MCM 898R) c - 96418A1 - Dipstick (MCM 228R. 260R) Used on: MCM 898R - S/N 6218462 and above MCM 228R - S/N 6225267 and above MCM 260R - S/N 6227757 and above Figure 5. MCM Engines, Starboard Mounted Dipstick 90-95693 485 ENGINE-6C-59 a - 86890A1 - Tube b - 87353 - Dipstick c - 49457 - Dipstick (MIE 230/260 V-Drive Engines and Engines That are Mounted Near Horizontal) Used on: MIE 228 - All MIE 230 - All MIE 255 - All MIE 260 - All Figure 6. MIE 305 and 350 CID Engines 90-95693 485 6C-60- ENGINE OIL PUMP INSTALLATION 1. Thoroughly clean gaskel and seal surfaces on oil pan. cylinder block, rear main bearing cap and crankcase front cover. IMPORTANT:454 CID MIEandsome MCMengines use a rubber plug to block off threaded holes into the cylinder block (located on each side of the rear main bearing cap). If oil pan does not have thru hole for attaching screw, install rubber plug to prevent oil leak. 2. Coat both sidesof oil pan sidegaskets with Perfect Seal and place gaskets in position on each side of cvlinder block. (Figure 7) 3. Apply a Vs" (3mm) bead of KTV Sealer to front and rear seal mating surfaces on cvlinder block rear main bearing cap. front cover and gaskets. (Figure 7) IMPORTANT: RTV Sealer sets up in about 15 minutes. Be sure to complete assembly promptly. 4. Install new front and rear seals, being sure ends of seals are butted properlv against side gaskets. 5. Apply a '/«" (3mm) bead of RTV Sealer to outer surface of seals. (Figure 7) This is extremeh important on inboard and \ -drive engines which have aluminum oil oans. 1 - Shaft Extension 2 - Shaft Coupling 3 - Pump Body 4 - Drive Gear and Shaft 5 - Idler Gear 6 - Pickup Screen and Pipe Figure 1. Oil Pump Assembly I he oil pump consists of 2 gears and a pressure regulator valve enclosed in a 2-piece housing. Oil pumpisdriven by distributor shaft which is driven bv a helical gear on camshaft. A baffle is incorporated on pickup screen toeliminate pressure loss and engine oil pump lubes are bent at special angles. 05038 7 - P