Kohler Command CV730- Manuals

1.3 Section 1 Safety and General Information 1 Engine Identification Numbers When ordering parts, or in any communicationinvolving 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 de...

1.4 Section 1Safety and General Information Oil Recommendations Using the proper type and weight of oil in thecrankcase is extremely important. So is checking oildaily and changing oil regularly. Failure to use thecorrect oil, or using dirty oil, causes premature enginewear and failure. Oil Type Use...

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)...

1.9 Section 1 Safety and General Information 1 General Specifications 1 Power (@3600 RPM, exceeds Society of Automotive Engineers-Small Engine Test Code J1940.) CV17 .........................................................................................................................................

1.10 Section 1Safety 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 D...

1.11 Section 1 Safety and General Information 1 Crankcase Governor Cross Shaft Bore I.D. 6 mm Shaft New .............................................................................................................. 6.025/6.050 mm (0.2372/0.2382 in.)Max. Wear Limit ......................................

1.12 Section 1Safety 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) ......................................................

1.13 Section 1 Safety and General Information 1 Ignition Spark Plug Type (Champion ® or Equivalent) ............................................. RC12YC, XC12YC, or Platinum 3071 Spark Plug Gap ............................................................................................... 0.76 mm (0...

1.14 Section 1Safety and General Information Piston, Piston Rings, and Piston Pin cont. Top and Middle Compression Ring End Gap New Bore - CV17 Top 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 Torque ................................................................................ 6.2 N·m (55 in. lb.) Valve Cover Valve Cover Fastener Torque Gasket Style Cover .................................................................

1.16 Section 1Safety and General Information General Torque Values Metric Fastener Torque Recommendations for Standard Applications Tightening Torque: N·m (in. lb.) + or - 10% Property Class Noncritical Fasteners Into Aluminum SizeM4 1.2 (11) 1.7 (15) 2.9 (26) 4.1 (36) 5.0 (44) 2.0 (18) M5 2.5 (22) ...

1.17 Section 1 Safety and General Information 1 English Fastener Torque Recommendations for Standard Applications Grade 2 or 5Fasteners IntoAluminum Size8-32 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...

2.1 Section 2 Tools & Aids 2 Section 2 Tools & 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’llincrease your...

2.4 Section 2Tools & Aids Special Tools You Can Make Flywheel Holding Tool A flywheel holding tool can be made out of an oldjunk flywheel ring gear as shown in Figure 2-1, andused in place of a strap wrench. 1. Using an abrasive cut-off wheel, cut out a six tooth segment of the ring gear as show...

3.1 Section 3 Troubleshooting 3 Section 3 Troubleshooting Troubleshooting Guide When troubles occur, be sure to check the simplecauses which, at first, may seem too obvious to beconsidered. For example, a starting problem could becaused by an empty fuel tank. Some general common causes of engine tro...

3.2 Section 3Troubleshooting 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. ...

3.3 Section 3 Troubleshooting 3 • Check the condition of the oil. Drain the oil into a container - the oil should flow freely. Check formetal chips and other foreign particles. Sludge is a natural by-product of combustion; asmall accumulation is normal. Excessive sludgeformation could indicate overr...

3.4 Section 3Troubleshooting 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 sequenceswhen necessary. 3. Recon...

3.5 Section 3 Troubleshooting 3 Air escaping from crankcase breather ...................................................... Rings or cylinder worn.Air escaping from exhaust system ............................................................ Defective exhaust valve/improper seating.Air escaping from ...

4.1 Section 4 Air Cleaner and Air Intake System 4 Section 4 Air Cleaner and Air Intake System Air Cleaners General These engines are equipped with a replaceable, high-density paper air cleaner element. Most are alsoequipped with an oiled-foam precleaner whichsurrounds the paper element. Three differ...

4.5 Section 4 Air Cleaner and Air Intake System 4 Heavy-Duty Air Cleaner General The heavy-duty air cleaner consists of a cylindricalhousing, typically mounted to a bracket, andconnected with a formed rubber hose to an adapter onthe carburetor or throttle body/intake manifold (EFIunits). The air cle...

4.6 Section 4Air Cleaner and Air Intake System Air Intake/Cooling System To ensure proper cooling, make sure the grass screen,cooling fan fins, and other external surfaces of theengine are kept clean at all times . Every 100 hours of operation (more often under extremely dusty or dirty conditions), ...

5.1 Section 5 Fuel System and Governor 5 Section 5 Fuel System and Governor Description The Command vertical twins use two different typesof fuel systems; carbureted, or electronic fuel injection(EFI). This section covers the standard carbureted fuelsystems. The EFI fuel systems are covered insubsec...

5.3 Section 5 Fuel System and Governor 5 Troubleshooting – Fuel System Related Causes Test 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 valve is open. d. Make sure vacuum and fu...

5.4 Section 5Fuel 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 removedpump. Internal damage may occur ifinstalled incorrectly. 5. Connect...

5.7 Section 5 Fuel System and Governor 5 Troubleshooting Checklist When the engine starts hard, runs roughly or stalls atlow idle speed, check the following areas beforeadjusting or disassembling the carburetor. • Make sure the fuel tank is filled with clean, freshgasoline. • Make sure the fuel tank...

5.9 Section 5 Fuel System and Governor 5 Figure 5-6. Carburetor Adjustments. 2. Preliminary Settings: Turn 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 warmbefore making ...

5.10 Section 5Fuel System and Governor 16.5 mm(0.65 in.) Turn CarburetorUpside Down Figure 5-7. Governed Idle Spring Location. Figure 5-8. Holding Throttle Lever Against IdleStop Screw (One-Barrel Carburetor). Carburetor Servicing (CV17-740) Nikki Carburetors Float Replacement If symptoms described ...

5.11 Section 5 Fuel System and Governor 5 Disassembly Use the carburetor repair kit (and the float repair kit iffloat components are to be replaced). Refer to Figure5-10 for parts identification. The Kohler part numberand the Nikki lot number are stamped on the chokeside flange on top of the carbure...

5.13 Section 5 Fuel System and Governor 5 Always use new gaskets when servicing or reinstallingcarburetors. Repair kits are available which includenew gaskets and other components. Service/repair kitsavailable for Nikki carburetors and affiliatedcomponents are: Carburetor Repair KitFloat KitHigh Alt...

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. Torque the screwsto 2.5 ± 0.3 N·m (23 ± 2.6 in. lb.) . Reattach the accelerator pump hose (if so equipped), andsecure with the cli...

5.19 Section 5 Fuel System and Governor 5 Figure 5-34. Installing Accelerator Pump HousingScrews and Hose. 8. Install the new clips onto each end of the new vacuum hose, and connect the hose onto thefittings. See Figure 5-34. Discard all the old parts. Choke Repair 1. Remove the carburetor from the ...

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 operatingconditions. The main fuel jet is calibrated at thefactory and i...

5.22 Section 5Fuel 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 suppliedon some engines. The purpose of this system is tomaintain a desired idle speed regardle...

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 pivotpin through the float hinge and secure with thenew retaining screw. See Figure 5-46. Figure 5-44. Removing Float a...

5.25 Section 5 Fuel System and Governor 5 Figure 5-53. Slow Jets and O-Ring Detail. 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 theparts in the overhaul kit. F...

5.30 Section 5Fuel 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 insubsection 5B. Refer to “Initial GovernorAdjustment” in that section for setting thegovernor on EFI-equ...

5.31 Section 5 Fuel System and Governor 5 Sensitivity Adjustment Governor sensitivity is adjusted by repositioning thegovernor spring in the holes of the governor lever. Ifspeed surging occurs with a change in engine load, thegovernor is set too sensitive. If a big drop in speedoccurs when normal lo...

5.32 Section 5Fuel System and Governor Choke Lever Detail Figure 5-68. Governor Used with Commercial Mower Air Cleaner (CV17-745). Commercial Mower GovernorArrangement The Commercial Mower governor arrangement shownin Figure 5-68 is used primarily on wide area walkbehind mower applications. The init...

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

5B.2 Section 5BEFI Fuel System WARNING: Explosive Fuel! Gasoline is extremely flammable and its vapors can explodeif ignited. Store gasoline only in approved containers, inwell ventilated, unoccupied buildings, away from sparks orflames. Do not fill the fuel tank while the engine is hot orrunning, s...

5B.3 Section 5B EFI Fuel System 5B Gasoline/Alcohol blends Gasohol (up to 10% ethyl alcohol, 90% unleadedgasoline by volume) is approved as a fuel for KohlerEFI engines. Other gasoline/alcohol blends are notapproved. Gasoline/Ether blends Methyl Tertiary Butyl Ether (MTBE) and unleadedgasoline blend...

5B.4 Section 5BEFI Fuel System During certain operating periods such as cold starts,warm up, acceleration, etc., an air/fuel ratio richerthan 14.7:1 is required and the system operates in an“open loop” mode. In “open loop” operation theoxygen sensor output is not used, and the controllingadjustments...

5B.5 Section 5B EFI Fuel System 5B Two different ECU styles have been used in CV EFIproduction. Each has a plastic case, but they differ inhaving a 24 pin or 32 pin connector block, and areidentified as MSE 1.0 or MSE 1.1 respectively. See Figures 5B-1 and 5B-2. Basic function and operatingcontrol r...

5B.7 Section 5B EFI Fuel System 5B General The throttle position sensor (TPS) is used to indicatethrottle plate angle to the ECU. Since the throttle (byway of the governor) reacts to engine load, the angleof the throttle plate is directly related to the load onthe engine. Figure 5B-6. TPS Location. ...

5B.8 Section 5BEFI Fuel System Figure 5B-7. Service Connector Plug, PlasticCased 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 theMalfunction Indicator Light (MIL). a. The light should blink on...

5B.10 Section 5BEFI Fuel System Oxygen Sensor General The engine (oil) temperature sensor (Figure 5B-8) isused by the system to help determine fuelrequirements for starting (a cold engine needs morefuel than one at or near operating temperature).Mounted in the oil filter adapter housing, it has atem...

5B.11 Section 5B EFI Fuel System 5B The oxygen sensor can function only after beingheated by exhaust temperatures to a minimum of375°C (709°F). A cold oxygen sensor will requireapproximately 1-2 minutes at moderate engine load towarm sufficiently to generate a voltage signal. Propergrounding is also...

5B.12 Section 5BEFI 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 mainharness connector from the ECU and set themeter to the Rx1 scale. Check the circuitcontinuity as follow...

5B.13 Section 5B EFI Fuel System 5B Figure 5B-12. Relay Connector. 3. Set meter for DC voltage. Touch red tester lead to the #30 terminal in relay connector. Areading of 12 volts should be indicated at alltimes. 4. Connect the red lead of meter to the #85 terminal in relay connector. Turn key switch...

5B.14 Section 5BEFI Fuel System 1. Filter Strainer In Fuel Supply 2. Electrical Connection3. Solenoid Winding Multi-OrificeDirector Plate WithCalibrated Opening 4. Valve Housing5. Armature6. Valve Body7. Valve Needle 1 2 3 4 5 6 7 Figure 5B-15. Style 2 Fuel Injector. General The fuel injectors mount...

5B.16 Section 5BEFI Fuel System 10. Remove the manifold mounting bolts and separate the throttle body/manifold from the engineleaving the TPS, fuel rail, air baffle, injectors andline connections intact. Discard the old gaskets. 11. Position the manifold assembly over an appropriate container and tu...

5B.17 Section 5B EFI Fuel System 5B Ignition System General A high-voltage, solid-state, battery ignition system isused with the EFI system. The ECU controls theignition output and timing through transistorizedcontrol of the primary current delivered to the coils.Based on input from the speed sensor...

5B.18 Section 5BEFI Fuel System Spark 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, butmust be resistor plugs or permanent damage to theECU will occur, in addition to affecting operation.P...

5B.19 Section 5B EFI Fuel System 5B pump preventing the continued delivery of fuel. Inthis situation, the MIL will go on, but it will go backoff after 4 cranking revolutions if system function isOK. Once the engine is running, the fuel pumpremains on. Service The fuel pumps are non-serviceable and m...

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 betweenthe regulator and the mounting bracket. Setthe mounting bracket into po...

5B.22 Section 5BEFI Fuel System General Special low permeation high-pressure fuel line withan SAE 30 R9 rating is required for safe and reliableoperation, due to the higher operating pressure of theEFI system. If hose replacement is necessary, orderFuel Line Service Kit Part No. 25 111 37-S (contain...

5B.23 Section 5B EFI Fuel System 5B Figure 5B-33. Idle Speed Screw Details. Initial Governor Adjustment The initial governor adjustment is especially criticalon EFI engines because of the accuracy and sensitivityof the electronic control system. Incorrect adjustmentcan result in overspeed, loss of p...

5B.26 Section 5BEFI 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 operationof voltage sensitive components such as the ECU, fuelpump, and injectors will be intermittent ...

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. ...

5B.32 Section 5BEFI Fuel System k n il B e d o C 2 D B O e d o C - P e l b a c il 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 / ...

5B.38 Section 5BEFI Fuel System Code: 61 Source:Explanation: Denotes the end of fault codes. Ifsignaled first, no other fault codesare present. Troubleshooting Flow Chart The following flow chart provides an alternativemethod of troubleshooting the EFI system. The chartwill enable you to review the ...

5B.40 Section 5BEFI Fuel System Flow Chart Diagnostic Aids Diagnostic Aid #1 “SYSTEM POWER” (MIL does not illuminate when key is turned “on”) Possible causes: 1. Battery2. Main system fuse3. MIL light bulb burned out4. MIL electrical circuit problem “24 Pin” (MSE 1.0) Plastic-Cased ECU: Pin circuits...

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. Inaddition to lubricating the bearing surfaces, thelubrication system supplies oi...

6.2 Section 6Lubrication 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. Iflow, add oil of the proper type up to the fullmark. Reinstall oil fill cap/dipstick and threadtight. Checking Oil Level The importance of c...

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 theoil filter. See Figures 6-4 and 6-5. Clean the areaaround the most accessible oil drain plug and theoil fill cap/dipstick. 2. Remove ...

6.4 Section 6Lubrication System To service the blower housing mounted oil cooler,clean the outside of the fins with a brush (see Figure6-7). Remove the two screws holding the cooler unitto the blower housing. Tilt the cooler downward asshown in Figure 6-8. Clean the inside of the coolerwith a brush ...

7.1 Section 7 Retractable Starter 7 Section 7 Retractable Starter WARNING: Spring Under Tension! Retractable starters contain a powerful, recoil spring that is under tension. Always wear safety goggles when servicing retractablestarters and carefully follow instructions in this section for relieving...

7.3 Section 7 Retractable Starter 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 thepulley as a package. WARNING: Spring Under Tension! Do not remove the spring from the keep...

7.4 Section 7Retractable Starter Figure 7-8. Installing Pulley and Spring intoHousing. 3. Install the pawl springs and pawls into the starter pulley. See Figure 7-9. Pulley & Spring Housing Pawl Pawl Spring 3. Do not attempt to rewind a spring that has come out of the keeper. Order and install a...

8.1 8 Section 8 Electrical System and Components Section 8 Electrical System and Components This section covers the operation, service, and repair ofthe electrical system components. Systems andcomponents covered in this section are: • Spark Plugs• Battery and Charging System• Electronic CD Ignition...

8.3 8 Section 8 Electrical System and Components 2. Keep the cables, terminals, and external surfaces of the battery clean. A build-up of corrosive acidor grime on the external surfaces can cause thebattery to self-discharge. Self-discharge occursrapidly when moisture is present. 3. Wash the cables,...

8.4 Section 8Electrical System and Components The SMART-SPARK ™ ignition system used on some models is an advanced version of the CD ignitionsystem used on other CV engines. Its operation can bebest understood by first understanding the standardsystem and how it works. Since both systems willcontinu...

8.5 8 Section 8 Electrical System and Components Kill Switch or‘‘Off’’ Position ofKey Switch IgnitionModules Spark Plug Magnet Flywheel 0.28/0.33 mm(0.011/0.013 in.)Air Gap The timing of the spark is controlled by the location of the flywheel magnet group as referenced to engine topdead center. Figu...

8.6 Section 8Electrical System and Components B. Capacitive Discharge with Electronic Spark Advance (SMART-SPARK ™ ) SMART-SPARK ™ equipped engines utilize an electronic capacitive discharge ignition system withelectronic spark advance. A typical application (Figure8-6) consists of the following com...

8.7 8 Section 8 Electrical System and Components Operation: The ignition module for this system operates in the same fashion as the fixed timingmodule, except the trigger circuit for thesemiconductor (L2, Figure 8-5) is replaced by thespark advance module (Figure 8-7). The pulse generated by the inp...

8.8 Section 8Electrical System and Components a. If one side is not firing, check all wiring, connections, and terminations on that side. Ifwiring is okay, replace ignition module andretest for spark. b. If the tester shows spark, but the engine misses or won’t run on that cylinder, try a newspark p...

8.9 8 Section 8 Electrical System and Components 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. Test 4. Test the ignition modules and connections. 1. Remove the blower housing f...

8.12 Section 8Electrical System and Components Figure 8-12. 2. Check the SAM part number stamped on the side of the housing. Verify that you have an analogSAM (ASAM) Part No. 24 584 10 or lower, not adigital SAM (DSAM) Part No. 24 584 18 andhigher. Follow sub-step a for testing an ASAMwith this test...

8.13 8 Section 8 Electrical System and Components Figure 8-14. Connected Tester Leads. The test procedure for twin cylinder SAMs will varyslightly, 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 (...

8.14 Section 8Electrical System and Components Figure 8-16. “Pass” Indicator. ** The tester is powered by a 9-volt battery. Most SAMs are designed to operate down to a minimumof 7.25 volts. If the tester battery drops below thatlevel, incorrect test readings will result. The testerbattery should be ...

8.17 8 Section 8 Electrical System and Components Ground-To-Kill Lead (White) Diode Keyswitch OptionalOil Sentry TM Switch(Indicator Light) OptionalOil Sentry TM Switch(Shutdown) 12 V. Battery Solenoid Starter Lights (Yellow) (Black) 3 Amp/70 WattFlywheel Stator IgnitionModules SparkPlug (Red) (Blue...

8.18 Section 8Electrical System and Components Figure 8-23. 3 Amp/70 Watt Stator. Stator The stator is mounted on the crankcase behind theflywheel. Follow the procedures in Section 9 -“Disassembly” and Section 11 - “Reassembly” if statorreplacement is necessary. Rectifier-Regulator The rectifier-reg...

8.19 8 Section 8 Electrical System and Components 3. Plug the tester into the proper AC outlet/power supply for tester being used. Turn on the powerswitch. See Figure 8-26. The ‘‘POWER’’ lightshould be illuminated and one of the four statuslights may be on as well. This does not represent the condit...

8.20 Section 8Electrical System and Components 6. Press the ‘‘TEST’’ button until a ‘‘click’’ is heard and then release. See Figure 8-27. Momentarilyone of the four status lights will illuminateindicating the partial condition of the part. a. If the ‘‘OK’’ (green) light comes on, disconnect the test...

8.22 Section 8Electrical System and Components Problem Test Conclusion 1. Trace B+ lead from rectifier- regulator to key switch, or otheraccessible connection. Disconnect itfrom switch or connection. Connectan ammeter from loose end of B+lead to positive terminal of battery.Connect DC voltmeter from...

8.23 8 Section 8 Electrical System and Components Troubleshooting Guide 3 Amp Battery Charging System with 70 Watt Lighting Stator NOTE: Zero ohmmeters on each scale to ensure accurate readings. Voltage tests should be made with engine running at 3000 RPM - no load. Battery must be good and fully ch...

8.24 Section 8Electrical System and Components Electric Starting Motors Some engines in this series use inertia drive startingmotors while most use solenoid shift starters. Theinertia drive types are covered first and the solenoidshift types following. Starting Motor Precautions NOTE: Do not crank t...

8.27 8 Section 8 Electrical System and Components Retaining Ring Installation 1. Position the retaining ring in the groove in one of the inner halves. Assemble the other half over thetop and slide on the outer collar. 2. Be certain the drive components are installed in correct sequence onto the arma...

8.29 8 Section 8 Electrical System and Components Figure 8-42. Style ‘‘B’’ Commutator End Cap withBrushes. 6. Install the thru bolts and tighten securely. 7. Lubricate the drive shaft with Kohler starter drive lubricant (see Section 2). Install the drivecomponents following the instructions forservi...

8.31 8 Section 8 Electrical System and Components Figure 8-45. Removing Solenoid Screws. 3. If the solenoid was mounted with Phillips head screws, separate the solenoid and plunger springfrom the drive end cap. If the solenoid wasmounted with external Torx head screws, theplunger is part of the sole...

8.33 8 Section 8 Electrical System and Components 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-...

8.34 Section 8Electrical System and Components Figure 8-56. Checking Brushes. Armature 1. Clean and inspect the commutator (outer surface). The mica insulation must be lower thanthe commutator bars (undercut) to ensure properoperation of the commutator. See Figure 8-57. Figure 8-58. Checking Armatur...

8.35 8 Section 8 Electrical System and Components Figure 8-60. Service Brush Kit. 5. Perform Steps 10-13 in the “Starter Reassembly” sequence. Installation must be done after thearmature, drive lever, and frame are installed, ifthe starter has been disassembled. Brush Replacement The brushes and spr...

8.37 8 Section 8 Electrical System and Components Figure 8-66. Installing Thrust Washer. 10. Starter reassembly when replacing the Brushes/ Brush Holder Assembly: a. Hold the starter assembly vertically on the end housing, and carefully position theassembled brush holder assembly, with thesupplied p...

8.39 8 Section 8 Electrical System and Components 12 volt Test LeadsMomentaryConnection Only 12 volt Test LeadsMomentaryConnection Only VOM Leads Manually PushPlunger “In” 12 volt Test LeadsConnect Only LongEnough to Test Solenoid Test Procedure Solenoid Shift Style Starters Disconnect all leads fro...

8.40 Section 8Electrical System and Components PlungerPushed “In” VOM MeterLeads 12 volt Test Leads Test 4. Solenoid Hold-In Coil/Contact ContinuityTest. Use an ohmmeter set to the audible or Rx2K scale, andconnect the two ohmmeter leads to the two large postterminals. Perform the preceding test (3)...

9.1 Section 9 Disassembly 9 Section 9 Disassembly WARNING: Accidental Starts! Disabling engine. Accidental starting can cause severeinjury or death. Before working on the engine or equipment, disable the engine as follows: 1) Disconnect thespark plug lead(s). 2) Disconnect negative (-) battery cable...

9.2 Section 9Disassembly Figure 9-2. Removing Oil Fill Cap/Dipstick. 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 fromthe engine. Two different styles ...

9.3 Section 9 Disassembly 9 Figure 9-8. Removing Commercial Mower Elementand Precleaner. Figure 9-6. Removing Standard Element andPrecleaner. 3. Remove the element cover, element and precleaner. See Figure 9-6. Figure 9-7. Removing Standard Air Cleaner Base. 4. Remove the two hex flange nuts securin...

9.5 Section 9 Disassembly 9 Figure 9-14. Removing Throttle Control Bracket. Figure 9-15. Removing Control Panel. Remove Fuel Pump WARNING: Explosive Fuel! Gasoline may be present in the carburetor and fuel system.Gasoline is extremely flammable and its vapors can explodeif ignited. Keep sparks, open...

9.6 Section 9Disassembly Figure 9-18. Removing Control Bracket. Figure 9-19. Removing Control Bracket and AirCleaner 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. ...

9.7 Section 9 Disassembly 9 3. Remove the carburetor, throttle linkage and governor lever as an assembly. Figure 9-22. Removing Carburetor and Linkage(Two-Barrel Model Pictured). Figure 9-23. Removing Carburetor Mounting Nuts(Commercial Mower Base Shown). 5. If necessary, the carburetor, throttle li...

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 platedscrew used for the rectifier-regulator groundstrap or lead. Remove the blower housing. SeeFigures 9-31 and 9-32. Figure 9-32. Removing B...

9.10 Section 9Disassembly Figure 9-37. Removing Valve Cover. Remove Ignition Modules 1. Disconnect the lead(s) from each ignition module. See Figure 9-38. Figure 9-38. Disconnect Lead(s) from IgnitionModules. 2. Rotate the flywheel so the magnet is away from the modules. See Figure 9-39. SMART-SPARK...

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 ignitionmodules. Remove Intake Manifold 1. Remove the four hex flange screws securing the intake manifold to the cylinder heads. Notewhich screws hold ...

9.12 Section 9Disassembly Figure 9-43. Removing Cylinder Head. 4. Remove the lifters from the lifter bores. Use a hydraulic lifter tool. Do not use a magnet toremove lifters. Mark the lifters by location, aseither intake or exhaust, and cylinder 1 or 2.Hydraulic lifters should always be reinstalled ...

9.13 Section 9 Disassembly 9 Figure 9-45. Removing Rocker Arm. 2. Compress the valve springs using a valve spring compressor. See Figure 9-46. Figure 9-46. Removing Valves with Valve SpringCompressor. 3. Once the valve spring is compressed, remove the following items. See Figures 9-47 and 9-48: • Va...

9.14 Section 9Disassembly Figure 9-51. Removing Flywheel Fastener UsingStrap Wrench. 2. Remove the hex flange screw and washer. 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 th...

9.15 Section 9 Disassembly 9 Figure 9-54. Removing Stator. 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 StatorWire Bracket. 2. Remove the two hex flange screws and the stator. See Figure 9...

9.17 Section 9 Disassembly 9 3. Repeat the above procedure for the other connecting rod and piston assembly. Remove Crankshaft 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. Remov...

10.1 Section 10 Inspection and Reconditioning 10 Section 10 Inspection and Reconditioning This section covers the operation, inspection, andrepair/reconditioning of major internal enginecomponents. The following components are notcovered in this section. They are covered in sections oftheir own: Air...

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

10.5 Section 10 Inspection and Reconditioning 10 Figure 10-5. Checking Cylinder Head Flatness. Carefully inspect the valve mechanism parts. Inspectthe valve springs and related hardware for excessivewear or distortion. Check the valves and valve seatarea or inserts for evidence of deep pitting, crac...

10.7 Section 10 Inspection and Reconditioning 10 Excessive Combustion Temperatures: The white deposits seen here indicate very high combustiontemperatures, usually due to a lean fuel mixture. Gum: Gum deposits usually result from using stale gasoline. Gum is a prevalent cause of valve sticking.The c...

10.8 Section 10Inspection and Reconditioning Valve Guides If a valve guide is worn beyond specifications, it willnot guide the valve in a straight line. This may resultin burnt valve faces or seats, loss of compression, andexcessive oil consumption. To check valve guide-to-valve stem clearance,thoro...

10.9 Section 10 Inspection and Reconditioning 10 Ring failure is usually indicated by excessive oilconsumption and blue exhaust smoke. When ringsfail, oil is allowed to enter the combustion chamberwhere it is burned along with the fuel. High oilconsumption can also occur when the piston ring endgap ...

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 endsof the expander are not overlapped. 2. Middle Compression Ring (Center Groove): Install the center ring using a pi...

10.12 Section 10Inspection and Reconditioning Figure 10-13. Removing Governor Gear. 2. Remove the locking tab thrust washer located under the governor gear assembly. 3. Carefully inspect the governor gear shaft and replace it only if it is damaged. After removingthe damaged shaft, press or lightly t...

10.14 Section 10Inspection and Reconditioning 5. After torquing, rotate the gear and check for freedom of movement. Make sure there is nobinding. If binding occurs, loosen the screws,reposition the pump, retorque the hex flangescrews and recheck the movement. Crankcase Breather System The breather s...

11.1 Section 11 Reassembly 11 Section 11 Reassembly General NOTE: Make sure the engine is assembled using all specified torque values, tightening sequences,and clearances. Failure to observespecifications could cause severe engine wearor damage. Always use new gaskets. Apply asmall amount of oil to ...

11.2 Section 11Reassembly Figure 11-2. Installing Oil Seal in Crankcase. Install Governor Cross Shaft 1. Lubricate the governor cross shaft bearing surfaces in the crankcase with engine oil. 2. Slide the small lower washer onto the governor cross shaft and install the cross shaft from theinside of t...

11.3 Section 11 Reassembly 11 Figure 11-7. Installing Crankshaft. Install Connecting Rods with Pistons andRings NOTE: The cylinders are numbered on the crankcase. Make sure to install the piston, connectingrod, and end cap into its appropriate cylinderbore as previously marked at disassembly. Do not...

11.4 Section 11Reassembly Figure 11-13. Aligning Crankshaft and CamshaftTiming Marks. Figure 11-11. Torquing Connecting Rod End Cap. 6. Repeat the above procedure for the other connecting rod and piston assembly. Install Camshaft 1. Liberally apply camshaft lubricant (see Section 2) to each of the c...

11.5 Section 11 Reassembly 11 Figure 11-14. Checking Camshaft End Play. 3. Apply pressure on the camshaft end play checking tool (pushing camshaft towardcrankshaft). Use a feeler gauge to measure thecamshaft end play between the shim spacer andthe checking tool. Camshaft end play should be 0.076/0.1...

11.6 Section 11Reassembly 6. Install the ten hex flange screws securing the oil pan to the crankcase. Torque the fasteners in thesequence 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 istypically installed in the #6 hole s...

11.7 Section 11 Reassembly 11 Figure 11-23. Clean and Dry Taper of Crankshaft. Install Flywheel WARNING: Damaging Crankshaft and Flywheel Can Cause Personal Injury! Using improper procedures to install the flywheel can crackor damage the crankshaft and/or flywheel. This not onlycauses extensive engi...

11.8 Section 11Reassembly Figure 11-26. Installing Fan. 3. If the engine has a plastic grass screen, snap the screen onto the fan. See Figure 11-27. Due to thepossibility of damaging the posts during removal,install the retainers on different posts from whichthey were removed. Start the retainers by...

11.9 Section 11 Reassembly 11 Figure 11-28. Installing Supports for Metal GrassScreen. 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 theblower housing is in place. Figure 11-30. Applying Camshaft Lubr...

11.11 Section 11 Reassembly 11 Figure 11-36. Installing Valves with Valve SpringCompressor. Install Cylinder Heads NOTE: Cylinder heads must be attached with the original type of mounting hardware, usingeither hex flange screws, or mounting studswith nuts and washers. The heads aremachined different...

11.12 Section 11Reassembly Figure 11-41. Install Push Rods in Their OriginalPosition. 2. Apply grease to the contact surfaces of the rocker arms and rocker arm pivots. Install the rockerarms and rocker arm pivots on one cylinder head,and start the two hex flange screws. 3. Torque the hex flange scre...

11.13 Section 11 Reassembly 11 Figure 11-43. Using Spanner Wrench to Lift RockerArm Over Push Rod. 5. Repeat the above steps for the remaining cylinder. Do not interchange parts from thecylinder heads. 6. Rotate the crankshaft to check for free operation of the valve train. Check the clearance betwe...

11.14 Section 11Reassembly Figure 11-46. Setting Ignition Module Air Gap. 6. Torque 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 ignitionmodules. Make sure th...

11.15 Section 11 Reassembly 11 NOTE: If the wires were disconnected from the ignition modules on engines with SMART-SPARK ™ , reattach the leads and seal the base of the terminal connectors with GE/Novaguard G661 (see Section 2) or Fel-ProLubri-Sel dielectric compound. The beadsshould overlap betwee...

11.16 Section 11Reassembly Install Blower Housing and Outer Baffles NOTE: Do not completely tighten screws until all items are installed to allow shifting for holealignment. 1. Pull the wire harness and spark plug leads out through the appropriate openings in theshrouding. See Figures 11-57 and 11-5...

11.18 Section 11Reassembly Figure 11-64. Rectifier-Regulator Ground Details. 2. Install the B+ terminal/lead into the center position of the rectifier-regulator plug andconnect the plug to the rectifier-regulator. SeeFigure 11-65. Figure 11-63. Oil Sentry™ Switch (Some Models). Install Control Panel...

11.19 Section 11 Reassembly 11 Install Valve Covers Three valve cover designs have been used. The earliesttype used a gasket and RTV sealant between the coverand sealing surface of the cylinder head. The secondtype had a black O-Ring installed in a groove on theunderside of the cover and may have me...

11.20 Section 11Reassembly Figure 11-70. Install Governor Lever to Shaft. 2. Make sure the throttle linkage is connected to the governor lever and the throttle lever on thecarburetor. See Figure 11-71. Figure 11-67. Installing Carburetor, ThrottleLinkage, and Governor Lever. Figure 11-68. Installing...

11.21 Section 11 Reassembly 11 Figure 11-73. Throttle Linkage Details. 3. Move the governor lever toward the carburetor as far as it will go (wide-open throttle) and hold inposition. 4. Insert a nail into the hole on the cross shaft and rotate the shaft counterclockwise as far as it will turn, then ...

11.22 Section 11Reassembly Figure 11-76. Connecting Governor Spring toGovernor Lever. Install Throttle and Choke Controls 1. One-Barrel Carburetor Models: Connect the choke linkage to the carburetor and chokeactuator lever. 10. Connect the Oil Sentry™ Indicator light wires. Attach governor spring to...

11.23 Section 11 Reassembly 11 3. Connect the governor spring from the throttle control bracket to the appropriate hole in thegovernor lever, as indicated in the applicablechart. Note that hole positions are counted fromthe pivot point of the governor lever. Governor Lever Governor Spring High Idle ...

11.24 Section 11Reassembly 8 mm Governor Lever and Hole Position/RPM Chart CV18 Engines Engine Mounted Throttle Control Pivot Shaft Spring Color Hole No. Standard Throttle Control High Idle WOT Intended Maximum RPM Spring Color Hole No. Orange Green Blue Orange Green Blue Purple Blue Green 444333221...

11.25 Section 11 Reassembly 11 Install Electric Starter Motor 1. Install the starter motor using the two hex flange screws. Position the lift bracket as shown to alsosecure the dipstick tube. See Figure 11-79. Someinertia-drive starters have a pinion cover andspacers on the starter bolts. 2. Torque ...

11.26 Section 11Reassembly Figure 11-81. Reinstalled Fuel Pump. 2. Install the fuel pump using the two hex flange screws. Torque the screws to 2.3 N·m (20 in. lb.) . Figure 11-83. Installing Fuel Line (CommercialMower Shown). Install Air Cleaner Assembly Refer to Section 4 for the air cleaner reasse...

11.27 Section 11 Reassembly 11 Figure 11-85. Torquing Base and Spitback CupMounting Nuts. Figure 11-84. Breather Hose and Separator Details. 2. Position a new gasket and the air cleaner base on the studs while carefully pulling the loose end ofthe rubber breather hose through the base untilproperly ...

11.29 Section 11 Reassembly 11 Figure 11-92. Install Oil Drain Plug(s). Prepare the Engine for Operation The engine is now completely reassembled. Beforestarting or operating the engine, be sure to do thefollowing. 1. Make sure all hardware is tightened securely. 2. Make sure the oil drain plugs, oi...