Kohler CV730 manual

S ER VICE M ANUAL V ERTICAL C RANKSHAFT COMMAND CV17-750[...]

Content s Section 1. Safety and General Information ............................................................................ Section 2. Tools & Aids .......................................................................................................... Section 3. T roubleshooting ..........................................................[...]

1.1 Section 1 Safety and General Information 1 Section 1 Safety and General Information Safety Precautions T o ensure safe operation please read the following statements and understand their meaning. Also refer to your equipment manufacturer's manual for other important safety information. This manual contains safety precautions which are expl[...]

1.2 Section 1 Safety and General Information Carbon Monoxide can cause severe nausea, fainting or death. A void inhaling exhaust fumes, and never run the engine in a closed building or confined area. W ARNING W ARNING Electrical Shock can cause injury . Do not touch wires while engine is running. CAUTION Uncoiling Spring can cause severe injury . W[...]

1.3 Section 1 Safety and General Information 1 Engine Identification Numbers When ordering parts, or in any communication involving an engine, always give the Model, Specification and Serial Numbers, including letter suffixes if there are any . The engine identification numbers appear on a decal, or decals, affixed to the engine shrouding. See Figu[...]

1.4 Section 1 Safety and General Information Oil Recommendations Using the proper type and weight of oil in the crankcase is extremely important. So is checking oil daily and changing oil regularly . Failure to use the correct oil, or using dirty oil, causes premature engine wear and failure. Oil T ype Use high-quality detergent oil of API (America[...]

1.5 Section 1 Safety and General Information 1 ¹Perform these maintenance procedures more frequently under extremely dusty, dirty conditions. ²Only required for Denso starters. Not necessary on Delco starters. Have a Kohler Engine Service Dealer perform this service. ³Cleanout Kits 25 755 20-S (black) or 25 755 21-S (gold) allow cooling areas to[...]

1.6 Section 1 Safety and General Information Figure 1-4. T ypical Engine Dimensions CV Series with St andard Flat Air Cleaner . Dimensions in millimeters. Inch equivalents shown in [ ].[...]

1.7 Section 1 Safety and General Information 1 Figure 1-5. T ypical Engine Dimensions CV Series with Commercial Mower Air Cleaner . Dimensions in millimeters. Inch equivalents shown in [ ].[...]

1.8 Section 1 Safety and General Information Figure 1-6. T ypical Engine Dimensions CV EFI Series with Heavy-Duty Air Cleaner . Dimensions in millimeters. Inch equivalents shown in [ ].[...]

1.9 Section 1 Safety and General Information 1 General Specifications 1 P ower (@3600 RPM, exceeds Society of Automotive Engineers-Small Engine T est Code J1940.) CV17 ............................................................................................................................... ............ 12.7 kW (17 HP) CV18 ....................[...]

1.10 Section 1 Safety and General Information General Specifications 1 cont. Oil Capacity (w/filter) - approximate, determined by oil filter and oil cooler used: ........................................................ 1.6-1.8 L (1.7-1.9 U.S. qt .) Angle of Operation - Maximum (At Full Oil Level) All Directions .................. 25 ° Blower Housi[...]

1.11 Section 1 Safety and General Information 1 Crankcase Governor Cross Shaft Bore I.D. 6 mm Shaft Ne w .............................................................................................................. 6.025/6.050 mm (0.2372/0.2382 in.) Max. W ear Limit ..................................................................................[...]

1.12 Section 1 Safety and General Information Cylinder Bore Cylinder Bore I.D. New - CV17 ............................................................................................. 73.006/73.031 mm (2.8742 /2.8752 in.) New - CV18,CV20,CV22 (624 cc) ......................................................... 77.000/77.025 mm (3.0315/3.0325 in.) New[...]

1.13 Section 1 Safety and General Information 1 Ignition Spark Plug T ype (Champion ® or Equivalent) ............................................. RC12YC, XC12YC, or Platinum 3071 Spark Plug Gap ............................................................................................... 0.76 mm (0.030 in.) Spark Plug T orque ...................[...]

1.14 Section 1 Safety and General Information Piston, Piston Rings, and Piston Pin cont. T op and Middle Compression Ring End Gap New Bore - CV17 T op Ring ............................................................................................... 0.180/0.380 mm (0.0071/0.0150 in.) Middle Ring ...................................................[...]

1.15 Section 1 Safety and General Information 1 Stator Mounting Screw T orque ................................................................................ 6.2 N·m (55 in. lb.) V alve Cover V alve Cover Fastener T orque Gasket Style Cover .................................................................................. 3.4 N·m (30 in. lb.) Bl[...]

1.16 Section 1 Safety and General Information General T orque V alues Metric Fastener T orque Recommendations for St andard Applications Tightening T orque: N·m (in. lb.) + or - 10% Property Class Noncritical Fasteners Into Aluminum Size M4 1.2 (11) 1.7 (15) 2.9 (26) 4.1 (36) 5.0 (44) 2.0 (18) M5 2.5 (22) 3.2 (28) 5.8 (51) 8.1 (72) 9.7 (86) 4.0 (3[...]

1.17 Section 1 Safety and General Information 1 English Fastener T orque Recommendations for S tandard Applications Grade 2 or 5 Fasteners Into Aluminum Size 8-32 2.3 (20) 2.8 (25) --------- 2.3 (20) 10-24 3.6 (32) 4.5 (40) --------- 3.6 (32) 10-32 3.6 (32) 4.5 (40) --------- --------- 1/4-20 7.9 (70) 13.0 (115) 18.7 (165) 7.9 (70) 1/4-28 9.6 (85) [...]

2.1 Section 2 T ools & Aids 2 Section 2 T ools & Aids Certain quality tools are designed to help you perform specific disassembly , repair , and reassembly procedures. By using tools designed for the job, you can properly service engines easier , faster , and safer! In addition, you’ll increase your service capabilities and customer satis[...]

2.2 Section 2 T ools & Aids ) . t n o c ( s l o o T n o i t p i r c s e D . o N t r a P / e c r u o S h c n e r W p a r t S l e e h w y l F . l a v o m e r g n i r u d l e e h w y l f d l o h o T 9 0 4 2 8 - R L K s l o o T E S l o o T r e t f i L e v l a V c i l u a r d y H . s r e t f i l c i l u a r d y h l l a t s n i d n a e v o m e r o T [...]

2.3 Section 2 T ools & Aids 2 s d i A n o i t p i r c s e D . o N t r a P / e c r u o S t n a c i r b u L t f a h s m a C ) 3 1 6 Z Z r a p s l a V ( S - 4 1 7 5 3 5 2 r e l h o K e s a e r G c i r t c e l e i D ) 1 6 6 G d r a u g a v o N / E G ( S - 1 1 7 5 3 5 2 r e l h o K e s a e r G c i r t c e l e i D ) o r P - l e F ( l e S - i r b u L [...]

2.4 Section 2 T ools & Aids Special T ools Y ou Can Make Flywheel Holding T ool A flywheel holding tool can be made out of an old junk flywheel ring gear as shown in Figure 2-1, and used in place of a strap wrench. 1. Using an abrasive cut-off wheel, cut out a six tooth segment of the ring gear as shown. 2. Grind off any burrs or sharp edges. 3[...]

3.1 Section 3 T roubleshooting 3 Section 3 T roubleshooting T roubleshooting Guide When troubles occur , be sure to check the simple causes which, at first, may seem too obvious to be considered. For example, a starting problem could be caused by an empty fuel tank. Some general common causes of engine troubles are listed below . Use these to locat[...]

3.2 Section 3 T roubleshooting Engine Will Not Idle 1. Dirt or water in the fuel system. 2. Stale fuel and/or gum in carburetor . 3. Faulty spark plugs. 4. Fuel supply inadequate. 5. Idle fuel adjusting needle improperly set (some models). 6. Idle speed adjusting screw improperly set. 7. Low compression. 8. Restricted fuel tank cap vent. 9. Engine [...]

3.3 Section 3 T roubleshooting 3 • Check the condition of the oil. Drain the oil into a container - the oil should flow freely . Check for metal chips and other foreign particles. Sludge is a natural by-product of combustion; a small accumulation is normal. Excessive sludge formation could indicate overrich carburetion, weak ignition, ov erextend[...]

3.4 Section 3 T roubleshooting Possible Cause Solution 1. Disassemble breather , clean parts thoroughly , reassemble, and recheck pressure. 2. Replace all worn or damaged seals and gaskets. Make sure all fasteners are tightened securely . Use appropriate torque values and sequences when necessary . 3. Recondition piston, rings, cylinder bore, valv [...]

3.5 Section 3 T roubleshooting 3 Air escaping from crankcase breather ...................................................... Rings or cylinder worn. Air escaping from exhaust system ............................................................ Defective exhaust valve/improper se ating. Air escaping from carburetor ...................................[...]

4.1 Section 4 Air Cleaner and Air Int ake System 4 Section 4 Air Cleaner and Air Int ake System Air Cleaners General These engines are equipped with a replaceable, high- density paper air cleaner element. Most are also equipped with an oiled-foam precleaner which surrounds the paper element. Three different types are used. The “standard” type a[...]

4.2 Section 4 Air Cleaner and Air Int ake System Figure 4-4. Precleaner on Commercial Mower T ype Air Cleaner . Figure 4-3. Precleaner on St andard Air Cleaner . Paper Element Service (St andard and Commercial Mower T ypes) Every 100 hours of operation (more often under extremely dusty or dirty conditions), replace the paper element. See Figures 4-[...]

4.3 Section 4 Air Cleaner and Air Int ake System 4 Wing Nut Air Cleaner Cover (Plenum*) Cover Ret aining Knob Air Cleaner Cover (St d.) Element Cover Nut Element Cover Element Precleaner Air Cleaner Base Rubber Seal Stud *Plenum air cleaner system does not use a precleaner . Knob Knob Seal Air Cleaner Cover Element Cover Nut Rubber Seal Precleaner [...]

4.4 Section 4 Air Cleaner and Air Int ake System Air Cleaner Components Whenever the air cleaner cover is remov ed, or the paper element or precleaner are serviced, check the following: Air Cleaner Element Cover and Seal - Make sure element cover is not bent or damaged. Make sure the rubber sleeve seal is in place on the stud to prev ent dust or di[...]

4.5 Section 4 Air Cleaner and Air Int ake System 4 Heavy-Duty Air Cleaner General The heavy-duty air cleaner consists of a cylindrical housing, typically mounted to a bracket, and connected with a formed rubber hose to an adapter on the carburetor or throttle body/intake manifold (EFI units). The air cleaner housing contains a paper element and inn[...]

4.6 Section 4 Air Cleaner and Air Int ake System Air Intake/Cooling System T o ensure proper cooling, make sure the grass screen, cooling fan fins, and other external surfaces of the engine are kept clean at all times . Every 100 hours of operation (more often under extremely dusty or dirty conditions), remove the blower housing and other cooling s[...]

5.1 Section 5 Fuel System and Governor 5 Section 5 Fuel System and Governor Description The Command vertical twins use tw o different types of fuel systems; carbureted, or electronic fuel injection (EFI). This section covers the standard carbureted fuel systems. The EFI fuel systems are covered in subsection 5B. The governor systems used are covere[...]

5.2 Section 5 Fuel System and Governor Fuel Filter Most engines are equipped with an in-line filter . P eriodically inspect the filter and replace with a genuine Kohler filter every 200 operating hours. Fuel Line In compliance with CARB Tier III Emission Regulations, carbureted engines with a “ Family ” identification number beginning with “6[...]

5.3 Section 5 Fuel System and Governor 5 T roubleshooting – Fuel System Related Causes T est Conclusion 1. Check the following: a. Make sure the fuel tank contains clean, fresh, proper fuel. b. Make sure the vent in fuel tank cap is open. c. Make sure the fuel valv e is open. d. Make sure vacuum and fuel lines to fuel pump are secured and in good[...]

5.4 Section 5 Fuel System and Governor 3. Remove the pulse line that connects the pump to the crankcase. 4. Install a new pump using the hex flange screws. NOTE: Make sure the orientation of the new pump is consistent with the removed pump. Internal damage may occur if installed incorrectly . 5. Connect the pulse line between the pump and crankcase[...]

5.5 Section 5 Fuel System and Governor 5 Figure 5-3. Slow Circuit. Fuel Inlet Float V alve Seat Float V alve Main Jet Float Main Emulsion Hole Idle Speed (RPM) Adjustment Screw Air Fuel Mixture Check V alve Spring Outlet Check V alve Leak Jet Adjustment Screw Diaphragm Spring Pump Diaphragm Inlet Check V alve ACCELERA TOR PUMP ASSEMBL Y (Some Carbu[...]

5.6 Section 5 Fuel System and Governor Figure 5-4. Main Circuit. Check V alve Spring Outlet Check V alve Leak Jet Adjustment Screw Diaphragm Spring Pump Diaphragm Inlet Check V alve ACCELERA TOR PUMP ASSEMBL Y (Some Carburetors) Fuel Shut-Off Solenoid with Main Jet Main Jet Main Nozzle Throttle V alve Choke V alve Main Air Bleed Jet Accelerator Pum[...]

5.7 Section 5 Fuel System and Governor 5 T roubleshooting Checklist When the engine starts hard, runs roughly or stalls at low idle speed, check the following areas before adjusting or disassembling the carburetor . • Make sure the fuel tank is filled with clean, fresh gasoline. • Make sure the fuel tank cap vent is not blocked and that it is o[...]

5.8 Section 5 Fuel System and Governor High Altitude Operation When operating the engine at altitudes of 1500 m (5000 ft.) and above, the fuel mixture tends to get over - rich. This can cause conditions such as black, sooty exhaust smoke, misfiring, loss of speed and power , poor fuel economy , and poor or slow governor response. T o compensate for[...]

5.9 Section 5 Fuel System and Governor 5 Figure 5-6. Carburetor Adjustments. 2. Preliminary Settings: T urn the adjusting needle out (counterclockwise) from lightly bottomed 2-1/4 turns. 3. Start the engine and run at half throttle for 5 to 10 minutes to warm up. The engine must be w arm before making final settings. Check that the throttle and cho[...]

5.10 Section 5 Fuel System and Governor 16.5 mm (0.65 in.) T urn Carburetor Up side Down Figure 5-7. Governed Idle Spring Location. Figure 5-8. Holding Throttle Lever Against Idle Stop Screw (One-Barrel Carburetor). Carburetor Servicing (CV17-740) Nikki Carburetors Float Replacement If symptoms described in the carburetor troubleshooting guide indi[...]

5.11 Section 5 Fuel System and Governor 5 Disassembly Use the carburetor repair kit (and the float repair kit if float components are to be replaced). Refer to Figure 5-10 for parts identification. The Kohler part number and the Nikki lot number are stamped on the choke side flange on top of the carburetor body . Refer to the parts manual for the c[...]

5.12 Section 5 Fuel System and Governor Figure 5-10. T ypical Carburetor - Exploded View . Inspection/Rep air T o clean vent ports, seats etc., use a good commercially available carburetor solv ent, such as Gumout™, and clean, dry compressed air to blow out internal channels and ports. Use a suitable shop rag to prevent debris from hitting someon[...]

5.13 Section 5 Fuel System and Governor 5 Always use new gaskets when servicing or reinstalling carburetors. Repair kits are available which include new gaskets and other components. Service/repair kits available for Nikki carburetors and affiliated components are: Carburetor Repair Kit Float Kit High Altitude Kit (1525-3048 m/5,000-10,000 ft.) Hig[...]

5.14 Section 5 Fuel System and Governor Figure 5-14. Installing Float Assembly . 6. Hold the carburetor body so the float assembly hangs vertically and rests lightly against the fuel inlet needle. The inlet needle should be fully seated but the center pin of the needle (on retainer clip end) should not be depressed. Check the float height adjustmen[...]

5.15 Section 5 Fuel System and Governor 5 Figure 5-19. Main Jet and Slow Jet Removed. 4. Remove the two screws securing the top cov er, gasket, and ground lead (fuel solenoid-equipped models). Discard the gasket and screws only . 5. Remove the idle speed and idle fuel adjusting screws and springs from the carburetor . Discard the parts. 2. Remove t[...]

5.16 Section 5 Fuel System and Governor Figure 5-22. Inst alling Plug into Slow Jet T ube. 10. Attach the inlet needle to the metal tang of the float with the wire clip. The formed 90° lip of the metal tang should point up , with the needle v alve hanging down . See Figure 5-23. Figure 5-21. Installing Slow Jet. Figure 5-25. Checking Float Height.[...]

5.17 Section 5 Fuel System and Governor 5 Figure 5-26. Installing Fuel Bowl O-Rings. 15. Install the fuel bowl onto the carburetor . Secure with the four original screws. T orque the screws to 2.5 ± 0.3 N·m (23 ± 2.6 in. lb.) . Reattach the accelerator pump hose (if so equipped), and secure with the clip. See Figure 5-27. 14. When the proper flo[...]

5.18 Section 5 Fuel System and Governor 2. Remove the three screws securing the cov er to the accelerator pump housing. Remove the cover , spring, and diaphragm. See Figure 5-30. Figure 5-30. Accelerator Pump Cover and Diaphragm Removed. 3. Remove the retaining ring over the rubber check valv e, using a snap ring pliers. Remove the check v alve fro[...]

5.19 Section 5 Fuel System and Governor 5 Figure 5-34. Inst alling Accelerator Pump Housing Screws and Hose. 8. Install the new clips onto each end of the new vacuum hose, and connect the hose onto the fittings. See Figure 5-34. Discard all the old parts. Choke Rep air 1. Remove the carburetor from the engine. Discard the old mounting gaskets for t[...]

5.20 Section 5 Fuel System and Governor Figure 5-38. Choke Shaft and S pring Det ails. 10. Slide the choke shaft and spring, into the carburetor . Pivot (preload) the shaft and set the inner leg of the spring, against the formed stop within the choke lever as originally assembled. See Figure 5-35. The opposing leg of the spring must still be betwee[...]

5.21 Section 5 Fuel System and Governor 5 Adjustment NOTE: Carburetor adjustments should be made only after the engine has warmed up. The carburetor is designed to deliver the correct fuel- to-air mixture to the engine under all operating conditions. The main fuel jet is calibrated at the factory and is not adjustable*. The idle fuel adjusting need[...]

5.22 Section 5 Fuel System and Governor Figure 5-41. Governed Idle Spring Location. Figure 5-40. Optimum Low Idle Fuel Settings. Models with Governed Idle System An optional governed idle control system is supplied on some engines. The purpose of this system is to maintain a desired idle speed regardless of ambient conditions (temperature, parasiti[...]

5.23 Section 5 Fuel System and Governor 5 Figure 5-45. Float and Inlet Needle Details. 6. Install the float and inlet needle down into the seat and carburetor body . Install the new pivot pin through the float hinge and secure with the new retaining screw . See Figure 5-46. Figure 5-44. Removing Float and Inlet Needle. 4. Clean the carburetor bowl [...]

5.24 Section 5 Fuel System and Governor Figure 5-50. Removing Float and Inlet Needle. 3. Use an appropriate size flat screwdriver , and carefully remove the two main jets from the carburetor . Note and mark the jets by location for proper reassembly . The main jets may be size/side specific. After the main jets are removed, the main nozzles can be [...]

5.25 Section 5 Fuel System and Governor 5 Figure 5-53. Slow Jets and O-Ring Det ail. 5. Remove the idle speed (RPM) adjustment screw and spring from the carburetor . Discard the parts. NOTE: The carburetor is now disassembled for appropriate cleaning and installation of the parts in the overhaul kit. Further disassembly is not necessary . The throt[...]

5.26 Section 5 Fuel System and Governor Figure 5-57. Inst alling Float Assembly . 14. Hold the carburetor body so the float assembly hangs vertically and rests lightly against the fuel inlet needle. The inlet needle should be fully seated but the center pin of the needle (on retainer clip end) should not be depressed. Check the float height adjustm[...]

5.27 Section 5 Fuel System and Governor 5 Figure 5-58. Checking Float Height. NOTE: Be sure to measure from the casting surface, not the rubber gasket, if still attached. 16. When the proper float height is obtained, carefully reinstall the fuel bowl, using new O-Rings onto the carburetor . Secure with the four original screws. T orque the screws t[...]

5.28 Section 5 Fuel System and Governor Figure 5-63. Choke Shaft and S pring Det ails. 10. Slide the choke shaft and spring into the carburetor . Pivot (preload) the shaft and set the inner leg of the spring, against the formed stop within the choke lever as originally assembled. See Figure 5-60. The opposing leg of the spring must still be between[...]

5.29 Section 5 Fuel System and Governor 5 1. Carburetor Body Subassembly 2. Idle Speed Screw 3. Idle Speed Spring 4. Screw 5. Ground Lead 6. Retaining W asher 7. Slow Jet - RH Side 8. Slow Jet - LH Side 9. O-Ring (Slow Jet) (2) 10. Fuel Bowl 11. O-Ring (Fuel Bowl - Upper) 12. O-Ring (Fuel Bowl - Lower) 13. Drain Screw 14. Bowl Screw (4) 15. Fuel So[...]

5.30 Section 5 Fuel System and Governor Figure 5-66. Governor Controls and Linkage (External). Initial Adjustment NOTE: EFI engines require a special initial adjustment procedure, which is covered in subsection 5B. Refer to “Initial Governor Adjustment” in that section for setting the governor on EFI-equipped engines. Procedure - Carburetor Equ[...]

5.31 Section 5 Fuel System and Governor 5 Sensitivity Adjustment Governor sensitivity is adjusted by repositioning the governor spring in the holes of the gov ernor lever . If speed surging occurs with a change in engine load, the governor is set too sensitiv e. If a big drop in speed occurs when normal load is applied, the governor should be set f[...]

5.32 Section 5 Fuel System and Governor Choke Lever Det ail Figure 5-68. Governor Used with Commercial Mower Air Cleaner (CV17-745). Commercial Mower Governor Arrangement The Commercial Mower governor arrangement shown in Figure 5-68 is used primarily on wide area walk behind mower applications. The initial adjustment and sensitivity adjustment is [...]

5.33 Section 5 Fuel System and Governor 5 W asher Lock Nut Choke Linkage Bushing Sp acer Spring W asher Choke Cable Clamp and Screw Control Bracket Screw Spring W asher Hex Nut Screw Throttle Control Lever Lock Nut Throttle Cable Bushing Throttle Linkage Fuel Pump Clamp Fuel Throttle Shaft Bushing Throttle Shaft Bracket Deflector (If So Equipped) T[...]

5B.1 Section 5B EFI Fuel System 5B Section 5B Electronic Fuel Injection (EFI) Fuel System Content s Page(s) Description Initial Starting/Priming Procedure ............................................................................................. ............................ 5B.2 Fuel Recommendations ..............................................[...]

5B.2 Section 5B EFI Fuel System W ARNING: Explosive Fuel! Gasoline is extremely flammable and its vapors can explode if ignited. Store gasoline only in appr oved containers, in well ventilated, unoccupied buildings, away from sparks or flames. Do not fill the fuel tank while the engine is hot or running, since spilled fuel could ignite if it comes [...]

5B.3 Section 5B EFI Fuel System 5B Gasoline/Alcohol blends Gasohol (up to 10% ethyl alcohol, 90% unleaded gasoline by volume) is approved as a fuel for Kohler EFI engines. Other gasoline/alcohol blends are not approved. Gasoline/Ether blends Methyl T ertiary Butyl Ether (MTBE) and unleaded gasoline blends (up to a maximum of 15% MTBE by volume) are[...]

5B.4 Section 5B EFI Fuel System During certain operating periods such as cold starts, warm up, acceleration, etc., an air/fuel ratio richer than 14.7:1 is required and the system operates in an “open loop” mode. In “open loop” operation the oxygen sensor output is not used, and the controlling adjustments are based on the primary sensor sig[...]

5B.5 Section 5B EFI Fuel System 5B T wo different ECU styles have been used in CV EFI production. Each has a plastic case, but they differ in having a 24 pin or 32 pin connector block, and are identified as MSE 1.0 or MSE 1.1 respectively . See Figures 5B-1 and 5B-2. Basic function and operating control remains the same between the tw o, however du[...]

5B.6 Section 5B EFI Fuel System General The engine speed sensor is essential to engine operation; constantly monitoring the rotational speed (RPM) of the crankshaft. A ferromagnetic 60-tooth ring gear with two consecutive teeth missing is mounted on the flywheel. The inductive speed sensor is mounted 1.5 ± 0.25 mm (0.059 ± 0.010 in.) aw ay from t[...]

5B.7 Section 5B EFI Fuel System 5B General The throttle position sensor (TPS) is used to indicate throttle plate angle to the ECU. Since the throttle (by way of the gov ernor) reacts to engine load, the angle of the throttle plate is directly related to the load on the engine. Figure 5B-6. TPS Location. Mounted on the throttle body/intake manifold [...]

5B.8 Section 5B EFI Fuel System Figure 5B-7. Service Connector Plug, Plastic Cased ECU Harness. 8. Hold the throttle against the idle speed stop screw , turn the ignition switch to the “on” position (do not start the engine), and observe the Malfunction Indicator Light (MIL). a. The light should blink on/off quickly for approximately 3 seconds [...]

5B.9 Section 5B EFI Fuel System 5B 11. Reconnect the battery cable and all external loads. Remove the rubber band from the throttle lever . Readjust the idle speed to the equipment manufacturer ’ s specified setting and recheck the high-speed, no-load RPM setting. Observe the overall performance. TPS Initialization Procedure For “32 Pin” (MSE[...]

5B.10 Section 5B EFI Fuel System Oxygen Sensor General The engine (oil) temperature sensor (Figure 5B-8) is used by the system to help determine fuel requirements for starting (a cold engine needs more fuel than one at or near operating temperature). Mounted in the oil filter adapter housing, it has a temperature-sensitive resistor that extends int[...]

5B.11 Section 5B EFI Fuel System 5B The oxygen sensor can function only after being heated by exhaust temperatures to a minimum of 375°C (709°F). A cold oxygen sensor will require approximately 1-2 minutes at moderate engine load to warm sufficiently to generate a v oltage signal. Proper grounding is also critical. The oxygen sensor grounds throu[...]

5B.12 Section 5B EFI Fuel System b. If the resistance is less than 1.0 M Ω Ω Ω Ω Ω , the sensor is bad, replace it. 5. With the oxygen sensor disconnected and engine not running, disconnect the main harness connector from the ECU and set the meter to the Rx1 scale. Check the circuit continuity as follows: “24 Pin” (MSE 1.0) Plastic-Ca[...]

5B.13 Section 5B EFI Fuel System 5B Figure 5B-12. Relay Connector . 3. Set meter for DC voltage. T ouch red tester lead to the #30 terminal in relay connector . A reading of 12 volts should be indicated at all times. 4. Connect the red lead of meter to the #85 terminal in relay connector . T urn key switch to the “ on ” position. Battery voltag[...]

5B.14 Section 5B EFI Fuel System 1. Filter S trainer In Fuel Supply 2. Electrical Connection 3. Solenoid Winding Multi-Orifice Director Plate With Calibrated Opening 4. V alve Housing 5. Armature 6. V alve Body 7. V alve Needle 1 2 3 4 5 6 7 Figure 5B-15. Style 2 Fuel Injector . General The fuel injectors mount into the throttle body/intake manifol[...]

5B.15 Section 5B EFI Fuel System 5B Figure 5B-18. V olt Noid Light. 1. Disconnect the electrical connector from both injectors. Plug a 12 volt noid light (part of EFI Service Kit, see Section 2) into one connector . 2. Make sure all safety switch requirements are met. Crank the engine and check for flashing of the test light. Repeat test at other c[...]

5B.16 Section 5B EFI Fuel System 10. Remove the manifold mounting bolts and separate the throttle body/manifold from the engine leaving the TPS, fuel rail, air baffle, injectors and line connections intact. Discard the old gaskets. 11. Position the manifold assembly ov er an appropriate container and turn the key switch “on” to activate the fue[...]

5B.17 Section 5B EFI Fuel System 5B Ignition System General A high-voltage, solid-state, battery ignition system is used with the EFI system. The ECU controls the ignition output and timing through transistorized control of the primary current delivered to the coils. Based on input from the speed sensor , the ECU determines the correct firing point[...]

5B.18 Section 5B EFI Fuel System Sp ark Plugs EFI engines are equipped with Champion ® RC12YC (Kohler Part No. 12 132 02-S ) resistor spark plugs. Equivalent alternate brand plugs can also be used, but must be resistor plugs or permanent damage to the ECU will occur , in addition to affecting operation. Proper spark plug gap is 0.76 mm (0.030 in.)[...]

5B.19 Section 5B EFI Fuel System 5B pump preventing the continued deliv ery of fuel. In this situation, the MIL will go on, but it will go back off after 4 cranking revolutions if system function is OK. Once the engine is running, the fuel pump remains on. Service The fuel pumps are non-serviceable and must be replaced if determined to be faulty . [...]

5B.20 Section 5B EFI Fuel System Figure 5B-26. Fuel Pressure Regulator Det ails. Service Depending on the application, the regulator may be located in the fuel tank along with the fuel pump, or outside the tank just down line from the pump. The regulator is a sealed, non-serviceable assembly . If it is faulty , it must be separated from the base/ho[...]

5B.21 Section 5B EFI Fuel System 5B Fuel Rail 6. Install the new regulator by carefully pushing and rotating it slightly into the base or housing. a. External Regulators with Square Base Housing Only; Install a new O-Ring between the regulator and the mounting bracket. Set the mounting bracket into position. b. Secure the regulator in the base with[...]

5B.22 Section 5B EFI Fuel System General Special low permeation high-pressure fuel line with an SAE 30 R9 rating is required for safe and reliable operation, due to the higher operating pressure of the EFI system. If hose replacement is necessary , order Fuel Line Service Kit P art No. 25 111 37-S (containing 60” of high-pressure hose and 10 Oeti[...]

5B.23 Section 5B EFI Fuel System 5B Figure 5B-33. Idle Speed Screw Det ails. Initial Governor Adjustment The initial governor adjustment is especially critical on EFI engines because of the accuracy and sensitivity of the electronic control system. Incorrect adjustment can result in overspeed, loss of power , lack of response, or inadequate load co[...]

5B.24 Section 5B EFI Fuel System Figure 5B-37. Throttle Link in Center of Hole. Figure 5B-36. Inserting Feeler Gauge (Engines Without Stop Screw). b. On engines without a stop screw , pivot the throttle shaft and plate assembly into the “Full Throttle” position. Insert a 1.52 mm (0.060 in.) feeler gauge between the tang of the throttle shaft pl[...]

5B.25 Section 5B EFI Fuel System 5B 4. V erify that the governor has been set correctly . W ith the linkage still retained in the “Full Throttle” position (Step 2), unsnap the bushing clip, separate the linkage from the bushing, and remove the bushing from the lever . Follow Steps 3 and 4 in ‘‘Checking the Initial Adjustment’’. 5. Recon[...]

5B.26 Section 5B EFI Fuel System Electrical System The EFI system is a 12 VDC negative ground system, designed to operate down to a minimum of 7.0 volts. If system voltage drops below this level, the operation of voltage sensitive components such as the ECU, fuel pump, and injectors will be intermittent or disrupted, causing erratic operation or ha[...]

[...]

[...]

5B.29 Section 5B EFI Fuel System 5B “32 Pin” (MSE 1.1) Plastic-Cased ECU Systems Pin # 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 Function P ermanent Battery V oltage Switched Battery V oltage TPS Set; “ Auto-Learn” Initialization T erminal Throttle Position Sensor (TPS) and T emperature Sensor Gr[...]

5B.30 Section 5B EFI Fuel System Fuel System W ARNING: Fuel System Under Pressure! The fuel system operates under high pressur e. System pressur e must be relieved thr ough the test valve in the fuel rail prior to servicing or removal of any fuel system components. Do not smoke or work near heaters or other fire hazards. Have a fire extinguisher ha[...]

5B.31 Section 5B EFI Fuel System 5B Long Pause Short Pause Code 32 3 2 Code 61 1 6 Long Pause Light remains on at end of transmission 1. Diagnostic display initiated through ignition key sequencing. 2. Figure 5B-40. After the problem has been corrected, the fault codes may be cleared as follows. 1. Disconnect the negative (-) battery cable or the m[...]

5B.32 Section 5B EFI Fuel System k n i l B e d o C 2 D B O e d o C - P e l b a c i l p p A " n i P 2 3 " : o t ) 1 . 1 E S M ( - t s y S / U C E y l n O m e n o i t p i r c s e D e r u l i a F r o n o i t c e n n o C " n i P 4 2 " ) 0 . 1 E S M ( d e s a C - c i t s a l P m e t s y S / U C E " n i P 2 3 " ) 1 . 1 E S M[...]

5B.33 Section 5B EFI Fuel System 5B Code: 21 Source: Engine Speed Sensor Explanation: ECU receiving inconsistent tooth count signals from speed sensor . Expected Engine Response: P ossible misfire as ECU attempts to resynchronize during which time fuel and spark calculations are not made. Possible Causes: 1. Engine Speed Sensor Related a. Sensor co[...]

5B.34 Section 5B EFI Fuel System Code: 23 Source: ECU Explanation: ECU is unable to recognize or process signals from its memory . Expected Engine Response: Engine will not run. Possible Causes: 1. ECU (internal memory problem). a. Diagnosable only through the elimination of all other system/component faults. Code: 24 (Will not blink out) Source: E[...]

5B.35 Section 5B EFI Fuel System 5B Code: 33 Source: Oxygen Sensor/Fuel System Explanation: “System too Rich” T emporary fuel adaptation control is at the upper limit. Expected Engine Response: Erratic performance. Will run rich (smoke). Possible Causes: 1. Fuel Supply Related (nothing lean – only rich) a. Restricted return line causing exces[...]

5B.36 Section 5B EFI Fuel System Code: 42 Source: Engine (Oil) T emperature Sensor Explanation: Not sending proper signal to ECU. Expected Engine Response: Engine will be hard to start because ECU can’ t determine correct fuel mixture. Possible Causes: 1. T emperature Sensor Related a. Sensor wiring or connection. 2. Engine Wiring Harness Related[...]

5B.37 Section 5B EFI Fuel System 5B 3. Fuel Pump Relay Related a. Bad fuel pump relay . Primary side functional but pin 30 to pin 87 remains open. Primary side pin 85 to pin 86 is either open, or shorted during engine operation. Note: after key-off then key-on, code 56 would be set also. 4. ECU Related a. Circuit controlling injector #1 damaged. b.[...]

5B.38 Section 5B EFI Fuel System Code: 61 Source: Explanation: Denotes the end of fault codes. If signaled first, no other fault codes are present. T roubleshooting Flow Chart The following flow chart provides an alternative method of troubleshooting the EFI system. The chart will enable you to review the entire system in about 10-15 minutes. Using[...]

5B.39 Section 5B EFI Fuel System 5B Figure 5B-41. *Operate for an appropriate period of time based upon original fault codes.[...]

5B.40 Section 5B EFI Fuel System Flow Chart Diagnostic Aids Diagnostic Aid #1 “SYSTEM POWER” (MIL does not illuminate when key is turned “on”) Possible causes: 1. Battery 2. Main system fuse 3. MIL light bulb burned out 4. MIL electrical circuit problem “24 Pin” (MSE 1.0) Plastic-Cased ECU: Pin circuits 19 and 84. “32 Pin” (MSE 1.1)[...]

5B.41 Section 5B EFI Fuel System 5B Diagnostic Aid #5 “FUEL PUMP” (fuel pump not turning on) Possible causes: 1. Fuel pump fuse 2. Fuel pump circuit problem “24 Pin” (MSE 1.0) Plastic-Cased ECU: Circuits 30, 87, and relay . “32 Pin” (MSE 1.1) Plastic-Cased ECU: Circuits 30, 87, and relay . 3. Fuel pump Diagnostic Aid #6 “RELA Y” (re[...]

6.1 Section 6 Lubrication System 6 Section 6 Lubrication System General This engine uses a full pressure lubrication system, delivering oil under pressure to the crankshaft, camshaft, and connecting rod bearing surfaces. In addition to lubricating the bearing surfaces, the lubrication system supplies oil to the hydraulic valve lifters. A high-effic[...]

6.2 Section 6 Lubrication System Figure 6-2. Oil Fill Cap/Dipstick. 4. Remove dipstick and check oil level. The level should be between the FULL and ADD marks. If low , add oil of the proper type up to the full mark. Reinstall oil fill cap/dipstick and thread tight. Checking Oil Level The importance of checking and maintaining the proper oil level [...]

6.3 Section 6 Lubrication System 6 Change the oil as follows: 1. A drain plug is located on either side of the oil sump; one is near the starter , the other is near the oil filter . See Figures 6-4 and 6-5. Clean the area around the most accessible oil drain plug and the oil fill cap/dipstick. 2. Remove the selected drain plug and the oil fill cap/[...]

6.4 Section 6 Lubrication System T o service the blower housing mounted oil cooler , clean the outside of the fins with a brush (see Figure 6-7). Remove the two screws holding the cooler unit to the blower housing. Tilt the cooler downward as shown in Figure 6-8. Clean the inside of the cooler with a brush or with compressed air . After cleaning, r[...]

7.1 Section 7 Retract able St arter 7 Section 7 Retract able St arter W ARNING: Spring Under T ension! Retractable starters contain a powerful, recoil spring that is under tension. Always wear safety goggles when servicing retractable starters and carefully follow instructions in this section for relieving spring tension. Handle with Rope Retainer [...]

7.2 Section 7 Retract able St arter 6. Tie a single knot in one end of the new rope. 7. Rotate the pulley counterclockwise (when viewed from pawl side of pulley) until the spring is tight (approximately 6 full turns of pulley). 8. Rotate the pulley clockwise until the rope hole in the pulley is aligned with the rope guide bushing of the starter hou[...]

7.3 Section 7 Retract able St arter 7 Figure 7-6. Removing Pulley from Housing. 8. Note the position of the spring and keeper assembly in the pulley . See Figure 7-7. Remove the spring and keeper assembly from the pulley as a package. W ARNING: Spring Under T ension! Do not remove the spring fr om the keeper . Severe personal injury could result fr[...]

7.4 Section 7 Retract able St arter Figure 7-8. Installing Pulley and Spring into Housing. 3. Install the pawl springs and pawls into the starter pulley . See Figure 7-9. Pulley & Spring Housing Pawl Pawl S pring 3. Do not attempt to rewind a spring that has come out of the keeper . Order and install a new spring and keeper assembly . 4. Clean [...]

8.1 8 Section 8 Electrical System and Component s Section 8 Electrical System and Component s This section covers the operation, service, and repair of the electrical system components. Systems and components covered in this section are: • Spark Plugs • Battery and Charging System • Electronic CD Ignition System (including SMART - SP ARK ™ [...]

8.2 Section 8 Electrical System and Component s Normal: A plug taken from an engine operating under normal conditions will have light tan or gray colored deposits. If the center electrode is not worn, a plug in this condition could be set to the proper gap and reused. W et Fouled: A wet plug is caused by excess fuel or oil in the combustion chamber[...]

8.3 8 Section 8 Electrical System and Component s 2. Keep the cables, terminals, and external surfaces of the battery clean. A build-up of corrosive acid or grime on the external surfaces can cause the battery to self-discharge. Self-discharge occurs rapidly when moisture is present. 3. W ash the cables, terminals, and external surfaces with a mild[...]

8.4 Section 8 Electrical System and Component s The SMART -SP ARK ™ ignition system used on some models is an advanced v ersion of the CD ignition system used on other CV engines. Its operation can be best understood by first understanding the standard system and how it works. Since both systems will continue in use, it is advantageous to underst[...]

8.5 8 Section 8 Electrical System and Component s Kill Switch or ‘ ‘Off’ ’ Position of Key Switch Ignition Modules Sp ark Plug Magnet Flywheel 0.28/0.33 mm (0.01 1/0.013 in.) Air Gap The timing of the spark is controlled by the location of the flywheel magnet group as referenced to engine top dead center . Figure 8-4. Capacitive Discharge ([...]

8.6 Section 8 Electrical System and Component s B. Capacitive Discharge with Electronic Sp ark Advance (SMART -SP ARK ™ ) SMART -SP ARK ™ equipped engines utilize an electronic capacitive discharge ignition system with electronic spark adv ance. A typical application (Figure 8-6) consists of the following components: • A magnet assembly which[...]

8.7 8 Section 8 Electrical System and Component s Operation: The ignition module for this system operates in the same fashion as the fixed timing module, except the trigger circuit for the semiconductor (L2, Figure 8-5) is replaced by the spark advance module (Figure 8-7). The pulse generated by the input coil of the ignition module (L1, Figure 8-5[...]

8.8 Section 8 Electrical System and Component s a. If one side is not firing, check all wiring, connections, and terminations on that side. If wiring is okay , replace ignition module and retest for spark. b. If the tester shows spark, but the engine misses or won’ t run on that cylinder , try a new spark plug. c. If neither side is firing, reche[...]

8.9 8 Section 8 Electrical System and Component s Figure 8-8. 1. Make a line near the edge of the flywheel screen with a marking pen or narrow tape. 2. Connect an automotive timing light to cylinder that had good spark. T est 4. T est the ignition modules and connections. 1. Remove the blower housing from the engine. Inspect the wiring for any dama[...]

8.10 Section 8 Electrical System and Component s Ignition Module Resistance T able 4 ) P osition a 0.30 mm (0.012 in.) feeler gauge between the magnet and all three legs of the module. The ignition module air gap is critical to proper system performance. Do not attempt to set it with a business card or folded microfiche card, use the feeler gauge s[...]

8.11 8 Section 8 Electrical System and Component s a. If correct voltage is not measured, connect black voltmeter lead directly to the negative (-) post of the battery and test voltage again in both key positions. If correct voltage is now indicated, check the ground circuit connections. If the ground screw/bolt or any other fasteners in the ground[...]

8.12 Section 8 Electrical System and Component s Figure 8-12. 2. Check the SAM part number stamped on the side of the housing. V erify that you have an analog SAM (ASAM) P art No. 24 584 10 or lower , not a digital SAM (DSAM) Part No. 24 584 18 and higher . Follow sub-step a for testing an ASAM with this tester . Digital SAM (DSAM) modules require [...]

8.13 8 Section 8 Electrical System and Component s Figure 8-14. Connected T ester Leads. The test procedure for twin cylinder SAMs will vary slightly , depending on whether the module is analog (ASAM) or digital (DSAM). 1. Check the SAM part number stamped on the end of the housing. a. If it is an ASAM (24 584 09 or 24 584 10), separate the short y[...]

8.14 Section 8 Electrical System and Component s Figure 8-16. “Pass” Indicator . ** The tester is powered by a 9-volt battery . Most SAMs are designed to operate down to a minimum of 7.25 volts. If the tester battery drops below that level, incorrect test readings will result. The tester battery should be checked periodically by connecting a DC[...]

8.15 8 Section 8 Electrical System and Component s 15/20/25 Amp Regulated Charging System Figure 8-17. Wiring Diagram - 15/20/25 Amp Regulated Battery Charging System with Fixed Timing.[...]

8.16 Section 8 Electrical System and Component s Figure 8-19. 15 Amp St ator and Rectifier-Regulator . Figure 8-20. 20 Amp St ator and Rectifier-Regulator . Figure 8-18. Wiring Diagram - 15/20/25 Amp Regulated Battery Charging System with V ariable Ignition Timing SMART -SP ARK ™ .[...]

8.17 8 Section 8 Electrical System and Component s Ground-T o-Kill Lead (White) Diode Keyswitch Optional Oil Sentry TM Switch (Indicator Light) Optional Oil Sentry TM Switch (Shut down) 12 V . Battery Solenoid St arter Light s (Y ellow) (Black) 3 Amp/70 Watt Flywheel St ator Ignition Modules Sp ark Plug (Red) (Blue) R A S B GND Light Optional Fuse [...]

8.18 Section 8 Electrical System and Component s Figure 8-23. 3 Amp/70 W att St ator . St ator The stator is mounted on the crankcase behind the flywheel. Follow the procedures in Section 9 - “Disassembly” and Section 11 - “Reassembly” if stator replacement is necessary . Rectifier-Regulator The rectifier-regulator is mounted on the blower [...]

8.19 8 Section 8 Electrical System and Component s 3. Plug the tester into the proper AC outlet/pow er supply for tester being used. T urn on the power switch. See Figure 8-26. The ‘‘POWER’’ light should be illuminated and one of the four status lights may be on as well. This does not represent the condition of the part. Figure 8-27. a. If [...]

8.20 Section 8 Electrical System and Component s 6. Press the ‘‘TEST’’ button until a ‘‘click’’ is heard and then release. See Figure 8-27. Momentarily one of the four status lights will illuminate indicating the partial condition of the part. a. If the ‘‘OK’’ (green) light comes on, disconnect the tester black lead attached[...]

8.21 8 Section 8 Electrical System and Component s Figure 8-33. Connections for T esting Charging System. Figure 8-32. 3. Plug the tester into the proper AC outlet/pow er supply for tester being used. T urn on the power switch. The ‘‘POWER’’ light should be illuminated and one of the four status lights may be on as well. See Figure 8-26. Th[...]

8.22 Section 8 Electrical System and Component s Problem T est Conclusion 1. T race B+ lead from rectifier- regulator to key switch, or other accessible connection. Disconnect it from switch or connection. Connect an ammeter from loose end of B+ lead to positive terminal of battery . Connect DC voltmeter from loose end of B+ lead to negative termin[...]

8.23 8 Section 8 Electrical System and Component s T roubleshooting Guide 3 Amp Battery Charging System with 70 W att Lighting St ator NOTE: Zero ohmmeters on each scale to ensure accurate readings. V oltage tests should be made with engine running at 3000 RPM - no load. Battery must be good and fully charged. Problem No Charge to Battery No Light [...]

8.24 Section 8 Electrical System and Component s Electric St arting Motors Some engines in this series use inertia drive starting motors while most use solenoid shift starters. The inertia drive types are cov ered first and the solenoid shift types following. St arting Motor Precautions NOTE: Do not crank the engine continuously for more than 10 se[...]

8.25 8 Section 8 Electrical System and Component s Operation - Inertia Drive St arters When power is applied to the starter , the armature rotates. As the armature rotates, the drive pinion moves out on the drive shaft splines and into mesh with the flywheel ring gear . When the pinion reaches the end of the drive shaft, it rotates the flywheel and[...]

8.26 Section 8 Electrical System and Component s Figure 8-36. Assembling Inner Half of T ool Around Armature Shaf t and Ret aining Ring. 5. Thread the center screw into the removal tool until you feel resistance. Use a wrench (1-1/8" or adjustable) to hold the base of the removal tool. Use another wrench or socket (1/2" or 13 mm) to turn [...]

8.27 8 Section 8 Electrical System and Component s Retaining Ring Inst allation 1. Position the retaining ring in the groove in one of the inner halves. Assemble the other half over the top and slide on the outer collar . 2. Be certain the drive components are installed in correct sequence onto the armature shaft. 3. Slip the tool over the end of t[...]

8.28 Section 8 Electrical System and Component s NOTE: Use a brush holder tool to keep the brushes in the pockets. A brush holder tool can easily be made from thin sheet metal. See Figure 8-40. Figure 8-40. Brush Holder T ool (Style ‘ ‘ A ’’ End Cap). Style ‘ ‘B’ ’ End Cap Brush Replacement Starters with Style ‘‘B’’ end caps[...]

8.29 8 Section 8 Electrical System and Component s Figure 8-42. Style ‘ ‘B’’ Commut ator End Cap with Brushes. 6. Install the thru bolts and tighten securely . 7. Lubricate the drive shaft with Kohler starter drive lubricant (see Section 2). Install the drive components following the instructions for servicing the starter drive. Solenoid Sh[...]

8.30 Section 8 Electrical System and Component s St arter Disassembly 1. Disconnect the lead wire from the solenoid. 2. Remove the hex nuts securing the solenoid, and remove the solenoid from the starter assembly . 3. Remove the tw o thru bolts. 4. Remove the commutator end cap. 5. Remove the insulator and the brush springs from the brush spring ho[...]

8.31 8 Section 8 Electrical System and Component s Figure 8-45. Removing Solenoid Screws. 3. If the solenoid was mounted with Phillips head screws, separate the solenoid and plunger spring from the drive end cap. If the solenoid w as mounted with external T orx head screws, the plunger is part of the solenoid, unhook the plunger pin from the drive [...]

8.32 Section 8 Electrical System and Component s Figure 8-48. Removing Thru Bolts. 5. Remove the commutator end plate assembly , containing the brush holder , brushes, springs, and locking caps. Remove the thrust w asher from inside the commutator end. See Figure 8-49. Figure 8-49. Removing Commutator End Plate Assembly . 6. Remove the frame from t[...]

8.33 8 Section 8 Electrical System and Component s Figure 8-54. Removing Retaining Ring. 12. Remove the drive pinion assembly from the armature. 13. Clean the parts as required. NOTE: Do not soak the armature or use solvent when cleaning. Wipe clean using a soft cloth, or use compressed air . Figure 8-53. Ret aining Ring Det ail. 11. Remove the ret[...]

8.34 Section 8 Electrical System and Component s Figure 8-56. Checking Brushes. Armature 1. Clean and inspect the commutator (outer surface). The mica insulation must be lower than the commutator bars (undercut) to ensure proper operation of the commutator . See Figure 8-57. Figure 8-58. Checking Armature. 3. Check for continuity between the armatu[...]

8.35 8 Section 8 Electrical System and Component s Figure 8-60. Service Brush Kit. 5. Perform Steps 10-13 in the “Starter Reassembly” sequence. Installation must be done after the armature, drive lever , and frame are installed, if the starter has been disassembled. Brush Replacement The brushes and springs are serviced as a set (4). Use Brush [...]

8.36 Section 8 Electrical System and Component s Figure 8-62. Installing Thrust W asher . 4. Apply a small amount of oil to the bearing in the drive end cap, and install the armature with the drive pinion. 5. Lubricate the fork end and center pivot of the drive lever with driv e lubricant (see Section 2). P osition the fork end into the space betwe[...]

8.37 8 Section 8 Electrical System and Component s Figure 8-66. Installing Thrust W asher . 10. Starter reassembly when replacing the Brushes/ Brush Holder Assembly: a. Hold the starter assembly vertically on the end housing, and carefully position the assembled brush holder assembly , with the supplied protective tube, against the end of the commu[...]

8.38 Section 8 Electrical System and Component s Figure 8-70. Inst alling Brush Holder Assembly using T ool with Extension. 11. Install the end cap onto the armature and frame, aligning the thin raised rib in the end cap with the corresponding slot in the grommet of the positive (+) brush lead. 12. Install the two thru bolts, and the two brush hold[...]

8.39 8 Section 8 Electrical System and Component s 12 volt T est Leads Momenta ry Connection Only 12 volt T est Leads Momenta ry Connection Only VOM Leads Manually Push Plunger “In” 12 volt T est Leads Connect Only Long Enough to T est Solenoid T est Procedure Solenoid Shif t Style S t arters Disconnect all leads from the solenoid including the[...]

8.40 Section 8 Electrical System and Component s Plunger Pushed “In” VOM Meter Leads 12 volt T est Leads T est 4. Solenoid Hold-In Coil/Cont act Continuity T est. Use an ohmmeter set to the audible or Rx2K scale, and connect the two ohmmeter leads to the two large post terminals. Perform the preceding test (3) and check for continuity . See Fig[...]

9.1 Section 9 Disassembly 9 Section 9 Disassembly W ARNING: Accident al S t art s! Disabling engine. Accidental starting can cause severe injury or death. Before working on the engine or equipment, disable the engine as follows: 1) Disconnect the spark plug lead(s). 2) Disconnect negative (-) battery cable fr om battery. General Clean all parts tho[...]

9.2 Section 9 Disassembly Figure 9-2. Removing Oil Fill Cap/Dip stick. 3. Remove the mounting screw and detach the oil fill tube. See Figure 9-3. 4. Remove and discard the oil filter . See Figure 9-4. Remove Oil Cooler If equipped, the oil cooler can now be removed from the engine. T wo different styles are used, see Figures 6-6 and 6-7 in Section [...]

9.3 Section 9 Disassembly 9 Figure 9-8. Removing Commercial Mower Element and Precleaner . Figure 9-6. Removing St andard Element and Precleaner . 3. Remove the element cover , element and precleaner . See Figure 9-6. Figure 9-7. Removing St andard Air Cleaner Base. 4. Remove the two hex flange nuts securing the spitback cup, baffle or bracket, and[...]

9.4 Section 9 Disassembly Figure 9-1 1. Air Cleaner Bracket/V alve Cover Mounting Screws (T wo-Barrel Model Pictured). Heavy Duty Air Cleaner 1. Disconnect the breather hose from the fitting in adapter or elbow . Remove the hex flange nuts securing the adapter and any attached clips to the mounting studs. See Figure 9-10. Figure 9-13. Removing Heav[...]

9.5 Section 9 Disassembly 9 Figure 9-14. Removing Throttle Control Bracket. Figure 9-15. Removing Control Panel. Remove Fuel Pump W ARNING: Explosive Fuel! Gasoline may be present in the carbur etor and fuel system. Gasoline is extremely flammable and its vapors can explode if ignited. Keep sparks, open flames and other sources of ignition away fro[...]

9.6 Section 9 Disassembly Figure 9-18. Removing Control Bracket. Figure 9-19. Removing Control Bracket and Air Cleaner Bracket (Some Models). 2. Disconnect the spring from the governor lever; note hole locations for reassembly . 3. Remove the choke linkage from the choke actuator lever and carburetor . Remove External Governor Controls 1. Loosen th[...]

9.7 Section 9 Disassembly 9 3. Remove the carburetor , throttle linkage and governor lev er as an assembly . Figure 9-22. Removing Carburetor and Linkage (T wo-Barrel Model Pictured). Figure 9-23. Removing Carburetor Mounting Nuts (Commercial Mower Base Shown). 5. If necessary , the carburetor , throttle linkage and governor lever can be separated.[...]

9.8 Section 9 Disassembly Figure 9-29. Removing Outer Baffles. 5. If the flywheel screen overlaps the blower housing, remove the fasteners and screen. If it was a metal screen with long bolts, also remov e the remaining loose hardware and cooling fan. See Figure 9-30. Figure 9-27. Loosening Sp ark Advance Module (Applicable Models). Figure 9-28. No[...]

9.9 Section 9 Disassembly 9 Figure 9-30. Removing Flywheel Screen. 6. Remove the remaining hex flange screws securing the blower housing. Note the one silver plated screw used for the rectifier-regulator ground strap or lead. Remove the blower housing. See Figures 9-31 and 9-32. Figure 9-32. Removing Blower Housing. Figure 9-31. Rectifier-Regulator[...]

9.10 Section 9 Disassembly Figure 9-37. Removing V alve Cover . Remove Ignition Modules 1. Disconnect the lead(s) from each ignition module. See Figure 9-38. Figure 9-38. Disconnect Lead(s) from Ignition Modules. 2. Rotate the flywheel so the magnet is away from the modules. See Figure 9-39. SMART -SP ARK ™ Module Leads Fixed Timing Ignition Modu[...]

9.11 Section 9 Disassembly 9 Figure 9-39. Position of Ignition Modules. 3. Remove the mounting screws and ignition modules. Note the position of the ignition modules. Remove Int ake Manifold 1. Remove the four hex flange screws securing the intake manifold to the cylinder heads. Note which screws hold the wiring clamps. 2. Remove the intake manifol[...]

9.12 Section 9 Disassembly Figure 9-43. Removing Cylinder Head. 4. Remove the lifters from the lifter bores. Use a hydraulic lifter tool. Do not use a magnet to remove lifters. Mark the lifters by location, as either intake or exhaust, and cylinder 1 or 2. Hydraulic lifters should always be reinstalled in the same position. See Figure 9-44. Figure [...]

9.13 Section 9 Disassembly 9 Figure 9-45. Removing Rocker Arm. 2. Compress the valve springs using a v alve spring compressor . See Figure 9-46. Figure 9-46. Removing V alves with V alve S pring Compressor . 3. Once the valv e spring is compressed, remove the following items. See Figures 9-47 and 9-48: • V alv e spring keepers • V alv e spring [...]

9.14 Section 9 Disassembly Figure 9-51. Removing Flywheel Fastener Using Strap W rench. 2. Remove the hex flange screw and w asher . 3. Use a puller to remove the flywheel from the crankshaft. See Figure 9-52. NOTE: Always use a flywheel puller to remove the flywheel from the crankshaft. Do not strike the crankshaft or flywheel, as these parts coul[...]

9.15 Section 9 Disassembly 9 Figure 9-54. Removing St ator . Remove Oil Pan Assembly 1. Remove the ten hex flange screws securing the oil pan to the crankcase. See Figure 9-55. Figure 9-53. Removing Backing Plates and St ator Wire Bracket. 2. Remove the two hex flange screws and the stator . See Figure 9-54. Note the position/routing of the stator [...]

9.16 Section 9 Disassembly Figure 9-60. Removing Connecting Rod End Cap. NOTE: If a carbon ridge is present at the top of either cylinder bore, use a ridge reamer tool to remove it before attempting to remove the piston. 2. Carefully remove the connecting rod and piston assembly from the cylinder bore. See Figure 9-61. NOTE: The cylinders are numbe[...]

9.17 Section 9 Disassembly 9 3. Repeat the above procedure for the other connecting rod and piston assembly . Remove Crankshaf t 1. Carefully pull the crankshaft from the crankcase. See Figure 9-62. Figure 9-62. Removing Crankshaft. Figure 9-63. Removing Oil Seal. Remove Flywheel End Oil Seal 1. Remove the oil seal from the crankcase. See Figure 9-[...]

10.1 Section 10 Inspection and Reconditioning 10 Section 10 Inspection and Reconditioning This section covers the operation, inspection, and repair/reconditioning of major internal engine components. The following components are not covered in this section. They are cov ered in sections of their own: Air Cleaner , Section 4 Carburetor & Externa[...]

10.2 Section 10 Inspection and Reconditioning The connecting rod journal can be ground one size under . When grinding the crankshaft, grinding stone deposits can get caught in the oil passages, which could cause severe engine damage. Removing the crankpin plug when the crankshaft is ground provides easy access for removing any grinding deposits tha[...]

10.3 Section 10 Inspection and Reconditioning 10 1. Lower hone into bore and after centering, adjust so that the stones are in contact with the cylinder wall. Use of a commercial cutting-cooling agent is recommended. 2. With the low er edge of each stone positioned even with the lowest edge of the bore, start drill and honing process. Move the hone[...]

10.4 Section 10 Inspection and Reconditioning Figure 10-4. Measuring Piston Diameter . 2. Use an inside micrometer , telescoping gauge, or bore gauge and measure the cylinder bore. T ake the measurement approximately 63.5 mm (2.5 in.) below the top of the bore and perpendicular to the piston pin. 3. Piston-to-bore clearance is the difference betwee[...]

10.5 Section 10 Inspection and Reconditioning 10 Figure 10-5. Checking Cylinder Head Flatness. Carefully inspect the valv e mechanism parts. Inspect the valv e springs and related hardware for excessiv e wear or distortion. Check the v alves and v alve seat area or inserts for evidence of deep pitting, cracks, or distortion. Check clearance of the [...]

10.6 Section 10 Inspection and Reconditioning Normal: Even after long hours of operation a v alve can be reconditioned and reused if the face and margin are in good shape. If a valv e is worn to where the margin is less than 1/32" do not reuse it. The valv e shown was in operation for almost 1000 hours under controlled test conditions. Bad Con[...]

10.7 Section 10 Inspection and Reconditioning 10 Excessive Combustion T emperatures: The white deposits seen here indicate very high combustion temperatures, usually due to a lean fuel mixture. Gum: Gum deposits usually result from using stale gasoline. Gum is a prevalent cause of v alve sticking. The cure is to ream the valv e guides and clean or [...]

10.8 Section 10 Inspection and Reconditioning V alve Guides If a valv e guide is worn bey ond specifications, it will not guide the valv e in a straight line. This may result in burnt valv e faces or seats, loss of compression, and excessive oil consumption. T o check valv e guide-to-v alve stem clearance, thoroughly clean the valv e guide and, usi[...]

10.9 Section 10 Inspection and Reconditioning 10 Ring failure is usually indicated by excessive oil consumption and blue exhaust smoke. When rings fail, oil is allowed to enter the combustion chamber where it is burned along with the fuel. High oil consumption can also occur when the piston ring end gap is incorrect because the ring cannot properly[...]

10.10 Section 10 Inspection and Reconditioning Figure 10-10. Measuring Piston Ring Side Clearance. Install New Piston Rings T o install new piston rings, proceed as follows: NOTE: Rings must be installed correctly . Ring installation instructions are usually included with new ring sets. Follow instructions carefully . Use a piston ring expander to [...]

10.11 Section 10 Inspection and Reconditioning 10 Figure 10-12. Piston Ring Installation. 1. Oil Control Ring (Bottom Groove): Install the expander and then the rails. Make sure the ends of the expander are not overlapped. 2. Middle Compression Ring (Center Groove): Install the center ring using a piston ring expander tool. Make sure the “identif[...]

10.12 Section 10 Inspection and Reconditioning Figure 10-13. Removing Governor Gear . 2. Remove the locking tab thrust w asher located under the governor gear assembly . 3. Carefully inspect the governor gear shaft and replace it only if it is damaged. After removing the damaged shaft, press or lightly tap the replacement shaft into the oil pan to [...]

10.13 Section 10 Inspection and Reconditioning 10 Figure 10-16. Oil Pump, Oil Pickup, and Relief V alve (Original S tyle). Figure 10-17. Oil Pump, Plastic Oil Pickup, and One-Piece Relief V alve (Later Style). Inspection Inspect the oil pump housing, gear , and rotors for nicks, burrs, wear , or any visible damage. If any parts are worn or damaged,[...]

10.14 Section 10 Inspection and Reconditioning 5. After torquing, rotate the gear and check for freedom of movement. Make sure there is no binding. If binding occurs, loosen the screws, reposition the pump, retorque the hex flange screws and recheck the movement. Crankcase Breather System The breather system is designed to control the amount of oil[...]

11.1 Section 1 1 Reassembly 11 Section 1 1 Reassembly General NOTE: Make sure the engine is assembled using all specified torque values, tightening sequences, and clearances. Failure to observe specifications could cause severe engine wear or damage. Alw ays use new gaskets. Apply a small amount of oil to the threads of critical fasteners before as[...]

11.2 Section 1 1 Reassembly Figure 1 1-2. Installing Oil Seal in Crankcase. Inst all Governor Cross Shaf t 1. Lubricate the governor cross shaft bearing surfaces in the crankcase with engine oil. 2. Slide the small lower w asher onto the governor cross shaft and install the cross shaft from the inside of the crankcase. 3. 6 mm Governor Shaft: Insta[...]

11.3 Section 1 1 Reassembly 11 Figure 1 1-7. Inst alling Crankshaf t. Inst all Connecting Rods with Pistons and Rings NOTE: The cylinders are numbered on the crankcase. Make sure to install the piston, connecting rod, and end cap into its appropriate cylinder bore as previously marked at disassembly . Do not mix the end caps and connecting rods. NO[...]

11.4 Section 1 1 Reassembly Figure 1 1-13. Aligning Crankshaf t and Camshaf t Timing Marks. Figure 1 1-1 1. T orquing Connecting Rod End Cap. 6. Repeat the above procedure for the other connecting rod and piston assembly . Inst all Camshaf t 1. Liberally apply camshaft lubricant (see Section 2) to each of the cam lobes. Lubricate the camshaft beari[...]

11.5 Section 1 1 Reassembly 11 Figure 1 1-14. Checking Camshaf t End Play . 3. Apply pressure on the camshaft end play checking tool (pushing camshaft toward crankshaft). Use a feeler gauge to measure the camshaft end play between the shim spacer and the checking tool. Camshaft end play should be 0.076/0.127 mm (0.003/0.005 in.) . 4. If the camshaf[...]

11.6 Section 1 1 Reassembly 6. Install the ten hex flange screws securing the oil pan to the crankcase. T orque the fasteners in the sequence shown in Figure 11-18 to 24.4 N·m (216 in. lb) . On some engines one of the ten mounting screws is plated. The plated screw is typically installed in the #6 hole shown in Figure 11-18. Figure 1 1-19. T orqui[...]

11.7 Section 1 1 Reassembly 11 Figure 1 1-23. Clean and Dry T aper of Crankshaf t. Inst all Flywheel W ARNING: Damaging Crankshaf t and Flywheel Can Cause Personal Injury! Using improper pr ocedures to install the flywheel can crack or damage the crankshaft and/or flywheel. This not only causes extensive engine damage, but can also cause personal i[...]

11.8 Section 1 1 Reassembly Figure 1 1-26. Installing Fan. 3. If the engine has a plastic grass screen, snap the screen onto the fan. See Figure 11-27. Due to the possibility of damaging the posts during removal, install the retainers on different posts from which they were remov ed. Start the retainers by hand, then push them down with a 13 mm (1/[...]

11.9 Section 1 1 Reassembly 11 Figure 1 1-28. Installing Support s for Metal Grass Screen. 2. Tighten the supports with a torque wrench to 9.9 N·m (99 in. lb.) . See Figure 11-29. The grass screen will be installed to the supports after the blower housing is in place. Figure 1 1-30. Applying Camshaf t Lubricant to Bottom of Lif ters. 3. Note the m[...]

11.10 Section 1 1 Reassembly Figure 1 1-34. Intake V alve Seal Location. Assemble Cylinder Heads Prior to installation, lubricate all components with engine oil, paying particular attention to the lip of the valv e stem seal, valve stems, and v alve guides. Install the following items in the order listed below using a valv e spring compressor . See[...]

11.11 Section 1 1 Reassembly 11 Figure 1 1-36. Installing V alves with V alve Spring Compressor . Inst all Cylinder Heads NOTE: Cylinder heads must be attached with the original type of mounting hardware, using either hex flange screws, or mounting studs with nuts and washers. The heads are machined differently for studs than for screws, so the fas[...]

11.12 Section 1 1 Reassembly Figure 1 1-41. Install Push Rods in Their Original Position. 2. Apply grease to the contact surfaces of the rocker arms and rocker arm pivots. Install the rocker arms and rocker arm pivots on one cylinder head, and start the two hex flange screws. 3. T orque the hex flange screws to 11.3 N·m (100 in. lb.) . See Figure [...]

11.13 Section 1 1 Reassembly 11 Figure 1 1-43. Using Spanner W rench to Lif t Rocker Arm Over Push Rod. 5. Repeat the above steps for the remaining cylinder . Do not interchange parts from the cylinder heads. 6. Rotate the crankshaft to check for free operation of the valv e train. Check the clearance between the valv e spring coils at full lift. M[...]

11.14 Section 1 1 Reassembly Figure 1 1-46. Setting Ignition Module Air Gap. 6. T orque the screws to 4.0-6.2 N·m (35-55 in. lb.) . 7. Repeat steps 4 through 6 for the other ignition module. 8. Rotate the flywheel back and forth checking for clearance between the magnet and ignition modules. Make sure the magnet does not strike the modules. Check [...]

11.15 Section 1 1 Reassembly 11 NOTE: If the wires were disconnected from the ignition modules on engines with SMART - SP ARK ™ , reattach the leads and seal the base of the terminal connectors with GE/ Novaguard G661 (see Section 2) or Fel-Pro Lubri-Sel dielectric compound. The beads should overlap betw een the terminals* to form a solid bridge [...]

11.16 Section 1 1 Reassembly Inst all Blower Housing and Outer Baffles NOTE: Do not completely tighten screws until all items are installed to allow shifting for hole alignment. 1. Pull the wire harness and spark plug leads out through the appropriate openings in the shrouding. See Figures 11-57 and 11-58. Figure 1 1-57. Wires on St arter Side of E[...]

11.17 Section 1 1 Reassembly 11 Figure 1 1-59. Installing Blower Housing. 3. Position the outer baffles and secure using the four hex flange screws (two long, two short) in the front mounting holes (into cylinder head), including any lifting strap or attached bracket(s). Install the two short screws in the upper mounting holes of the outer baffles [...]

11.18 Section 1 1 Reassembly Figure 1 1-64. Rectifier-Regulator Ground Det ails. 2. Install the B+ terminal/lead into the center position of the rectifier-regulator plug and connect the plug to the rectifier-regulator . See Figure 11-65. Figure 1 1-63. Oil Sentry™ Switch (Some Models). Inst all Control Panel (If So Equipped) 1. Install the panel [...]

11.19 Section 1 1 Reassembly 11 Inst all V alve Covers Three valv e cover designs have been used. The earliest type used a gasket and RTV sealant between the cover and sealing surface of the cylinder head. The second type had a black O-Ring installed in a groove on the underside of the cover and may hav e metal spacers in the bolt holes. The newest[...]

11.20 Section 1 1 Reassembly Figure 1 1-70. Install Governor Lever to Shaf t. 2. Make sure the throttle linkage is connected to the governor lever and the throttle lev er on the carburetor . See Figure 11-71. Figure 1 1-67. Installing Carburetor , Throttle Linkage, and Governor Lever . Figure 1 1-68. Inst alling T wo-Barrel Carburetor . Figure 1 1-[...]

11.21 Section 1 1 Reassembly 11 Figure 1 1-73. Throttle Linkage Details. 3. Move the governor lev er toward the carburetor as far as it will go (wide-open throttle) and hold in position. 4. Insert a nail into the hole on the cross shaft and rotate the shaft counterclockwise as far as it will turn, then torque the hex nut to 6.8 N·m (60 in. lb.) . [...]

11.22 Section 1 1 Reassembly Figure 1 1-76. Connecting Governor Spring to Governor Lever . Inst all Throttle and Choke Controls 1. One-Barrel Carburetor Models: Connect the choke linkage to the carburetor and choke actuator lever . 10. Connect the Oil Sentry™ Indicator light wires. Attach governor spring to gov ernor lever . See Figure 11-76 and [...]

11.23 Section 1 1 Reassembly 11 3. Connect the governor spring from the throttle control bracket to the appropriate hole in the governor lev er , as indicated in the applicable chart. Note that hole positions are counted from the pivot point of the governor lev er . Governor Lever Governor S pring High Idle RPM Hole No. Color Code 3801- 4000 6 Clea[...]

11.24 Section 1 1 Reassembly 8 mm Governor Lever and Hole Position/RPM Chart CV18 Engines Engine Mounted Throttle Control Pivot Shaf t Spring Color Hole No. S tandard Throttle Control High Idle WOT Intended Maximum RPM Spring Color Hole No. Orange Green Blue Orange Green Blue Purple Blue Green 4 4 4 3 3 3 2 2 1 3888 3780 3672 3564 3456 3348 3240 31[...]

11.25 Section 1 1 Reassembly 11 Inst all Electric St arter Motor 1. Install the starter motor using the two hex flange screws. Position the lift bracket as shown to also secure the dipstick tube. See Figure 11-79. Some inertia-drive starters have a pinion cov er and spacers on the starter bolts. 2. T orque the two hex flange screws to 15.3 N·m (13[...]

11.26 Section 1 1 Reassembly Figure 1 1-81. Reinstalled Fuel Pump. 2. Install the fuel pump using the two hex flange screws. T orque the screws to 2.3 N·m (20 in. lb.) . Figure 1 1-83. Installing Fuel Line (Commercial Mower Shown). Inst all Air Cleaner Assembly Refer to Section 4 for the air cleaner reassembly procedure. St andard Air Cleaners 1. [...]

11.27 Section 1 1 Reassembly 11 Figure 1 1-85. T orquing Base and Spitback Cup Mounting Nut s. Figure 1 1-84. Breather Hose and Separator Det ails. 2. Position a new gasket and the air cleaner base on the studs while carefully pulling the loose end of the rubber breather hose through the base until properly seated (collars sealed against each side [...]

11.28 Section 1 1 Reassembly Figure 1 1-89. Securing Air Cleaner Mounting Bracket. 6. T wo-Barrel Carburetor Models Only: Attach the choke return spring to the bottom of the main control bracket. See Figure 11-90. Figure 1 1-90. Attaching Choke Return S pring (T w o- Barrel Carburetors). Choke Return Spring Inst all Muffler 1. Install the port line[...]

11.29 Section 1 1 Reassembly 11 Figure 1 1-92. Inst all Oil Drain Plug(s). Prepare the Engine for Operation The engine is now completely reassembled. Before starting or operating the engine, be sure to do the following. 1. Make sure all hardware is tightened securely . 2. Make sure the oil drain plugs, oil sentry pressure switch, and a new oil filt[...]

LITHO IN U.S.A. FORM NO.: TP-2450-C ISSUED: 3/94 REVISED: 3/06 ENGINE DIVISION, KOHLER CO., KOHLER, WISCONSIN 53044 FOR SALES AND SERVICE INFORMA TION IN U.S. AND CANADA, CALL 1-800-544-2444[...]