1. Manuals
  2. Brands
  3. Kohler Manuals
  4. Engine
  5. COMMAND CH20
  6. Service manual

Kohler Command CH20 Service Manual

Hide thumbs Also See for Command CH20:
Table of Contents

Advertisement

Quick Links

Download this manual
CH18, CH20, CH23, CH25, CH640, CH730, CH740
Liquefi ed Petroleum Gas (LPG) or LPG/Natural Gas (NG) Fueled
Service Manual
IMPORTANT:
Read all safety precautions and instructions carefully before operating equipment. Refer to operating
instruction of equipment that this engine powers.
Ensure engine is stopped and level before performing any maintenance or service.
2
Safety
3
Maintenance
5
Specifi cations
13
Tools and Aids
16
Troubleshooting
20
Air Cleaner/Intake
21
Fuel System
30
Governor System
32
Lubrication System
34
Electrical System
50
Starter System
57
Disassembly/Inspection and Service
73
Reassembly
24 690 30 Rev. G
KohlerEngines.com
1

Advertisement

Table of Contents
loading

Related Manuals for Kohler Command CH20

Summary of Contents for Kohler Command CH20

  • Page 1 CH18, CH20, CH23, CH25, CH640, CH730, CH740 Liquefi ed Petroleum Gas (LPG) or LPG/Natural Gas (NG) Fueled Service Manual IMPORTANT: Read all safety precautions and instructions carefully before operating equipment. Refer to operating instruction of equipment that this engine powers. Ensure engine is stopped and level before performing any maintenance or service.

  • Page 2: Safety Precautions

    Safety SAFETY PRECAUTIONS WARNING: A hazard that could result in death, serious injury, or substantial property damage. CAUTION: A hazard that could result in minor personal injury or property damage. NOTE: is used to notify people of important installation, operation, or maintenance information. WARNING WARNING WARNING...

  • Page 3: Maintenance Instructions

    PRO oil and PRO fi lter. ® REPAIRS/SERVICE PARTS Kohler genuine service parts can be purchased from Kohler authorized dealers. To fi nd a local Kohler authorized dealer visit KohlerEngines.com or call 1-800-544-2444 (U.S. and Canada). 24 690 30 Rev. G...

  • Page 4: Oil Recommendations

    KOHLER PRO Extended Life Oil Filter. Alternative (NOT required if using KOHLER PRO 10W-50 engine oils and oil fi lters may be used with KOHLER full-synthetic oil). Remove spark plug(s) and pour engines but require 100-Hour oil and 200-Hour oil fi lter about 1 oz.

  • Page 5: Specifications

    Specifi cations Engine Dimensions Dimensions in millimeters. Inch equivalents shown in [ ]. 24 690 30 Rev. G KohlerEngines.com...

  • Page 6: Engine Identification Numbers

    Lubricate threads with engine oil prior to assembly. Any and all horsepower (hp) references by Kohler are Certifi ed Power Ratings and per SAE J1940 & J1995 hp standards. Details on Certifi ed Power Ratings can be found at KohlerEngines.com.

  • Page 7: Torque Specifications

    Specifi cations CH18/CH20/ CH25/ TORQUE SPECIFICATIONS CH640 CH23 CH730/CH740 Crankcase Breather Cover Fastener 11.3 N·m (100 in. lb.) into new holes 7.3 N·m (65 in. lb.) into used holes Oil Drain Plug 13.6 N·m (10 ft. lb.) Cylinder Head Fastener (torque in 2 increments) fi...

  • Page 8: Clearance Specifications

    Specifi cations CH18/CH20/ CH25/ TORQUE SPECIFICATIONS CH640 CH23 CH730/CH740 Starter Assembly Thru Bolt Inertia Drive 4.5-5.7 N·m (40-50 in. lb.) Nippondenso Solenoid Shift 4.5-7.5 N·m (40-84 in. lb.) Delco-Remy Solenoid Shift 5.6-9.0 N·m (49-79 in. lb.) Mounting Screw 15.3 N·m (135 in. lb.) Brush Holder Mounting Screw 2.5-3.3 N·m (22-29 in.
  • Page 9 Specifi cations CH18/CH20/ CH25/ CLEARANCE SPECIFICATIONS CH640 CH23 CH730/CH740 Crankcase Governor Cross Shaft Bore I.D. 6 mm Shaft 6.025/6.050 mm (0.2372/0.2382 in.) Max. Wear Limit 6.063 mm (0.2387 in.) 8 mm Shaft 8.025/8.075 mm (0.3159/0.3179 in.) Max. Wear Limit 8.088 mm (0.3184 in.) Crankshaft End Play (free) 0.070/0.590 mm (0.0028/0.0230 in.)
  • Page 10 Specifi cations CH18/CH20/ CH25/ CLEARANCE SPECIFICATIONS CH640 CH23 CH730/CH740 Cylinder Head Max. Out-of-Flatness 0.076 mm (0.003 in.) 0.1 mm (0.004 in.) Governor Governor Cross Shaft-to-Crankcase Running Clearance 6 mm Shaft 0.013/0.075 mm (0.0005/0.0030 in.) 8 mm Shaft 0.025/0.126 mm (0.0009/0.0049 in.) Cross Shaft O.D.
  • Page 11 Specifi cations CH18/CH20/ CH25/ CLEARANCE SPECIFICATIONS CH640 CH23 CH730/CH740 Valves and Valve Lifters Hydraulic Valve Lifter to Crankcase Running Clearance 0.0241/0.0501 mm (0.0009/0.0020 in.) Intake Valve Stem-to-Valve Guide Running Clearance 0.038/0.076 mm (0.0015/0.0030 in.) Exhaust Valve Stem-to-Valve Guide Running Clearance 0.050/0.088 mm (0.0020/0.0035 in.) Intake Valve Guide I.D.

  • Page 12: General Torque Values

    Specifi cations GENERAL TORQUE VALUES English Fastener Torque Recommendations for Standard Applications Bolts, Screws, Nuts and Fasteners Assembled Into Cast Iron or Steel Grade 2 or 5 Fasteners Into Aluminum Size Grade 2 Grade 5 Grade 8 Tightening Torque: N·m (in. lb.) ± 20% 8-32 2.3 (20) 2.8 (25)
  • Page 13 Shrader Valve Adapter Hose DTI-037 Wire Probe Set (2 pieces regular wire with clip; 1 piece fused wire) DTI-031 Hose Removal Tool, Dual Size/End (also sold as individual Kohler tool) DTI-033 K-Line Adapter Jumper Lead Wiring Harness Kohler 25 176 23-S Kohler Wireless Diagnostic System Module (Bluetooth®)
  • Page 14 For reaming worn valve guides to accept replacement oversize valves. Can be used in low-speed drill press or with handle below for hand reaming. Reamer Handle Design Technology Inc. For hand reaming using Kohler 25 455 12-S reamer. DTI-K830 KohlerEngines.com 24 690 30 Rev. G...
  • Page 15 Dielectric Grease (GE/Novaguard G661) Kohler 25 357 11-S Dielectric Grease Loctite ® 51360 Kohler Electric Starter Drive Lubricant (Inertia Drive) Kohler 52 357 01-S Kohler Electric Starter Drive Lubricant (Solenoid Shift) Kohler 52 357 02-S RTV Silicone Sealant Loctite ®...

  • Page 16: Troubleshooting Guide

    Troubleshooting TROUBLESHOOTING GUIDE When troubles occur, be sure to check simple causes which, at fi rst, 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 and vary by engine specifi cation. Use these to locate causing factors.
  • Page 17 Troubleshooting EXTERNAL ENGINE INSPECTION Engine Loses Power NOTE: It is good practice to drain oil at a location away ● Dirty air cleaner element. from workbench. Be sure to allow ample time for ● Engine overheated. complete drainage. ● Excessive engine load. ●...

  • Page 18: Crankcase Vacuum Test

    Troubleshooting CRANKCASE VACUUM TEST WARNING WARNING Carbon Monoxide can cause severe nausea, Rotating Parts can cause severe injury. fainting or death. Stay away while engine is in operation. Avoid inhaling exhaust fumes. Never run engine indoors or in enclosed spaces. Keep hands, feet, hair, and clothing away from all Engine exhaust gases contain poisonous carbon moving parts to prevent injury.

  • Page 19: Compression Test

    Troubleshooting COMPRESSION TEST For Command Twins: A compression test is best performed on a warm engine. Clean any dirt or debris away from base of spark plug(s) before removing them. Be sure choke is off , and throttle is wide open during test. Compression should be at least 160 psi and should not vary more than 15% between cylinders.

  • Page 20: Air Cleaner

    Air Cleaner/Intake AIR CLEANER BREATHER TUBE These systems are CARB/EPA certifi ed and components Ensure sure both ends of breather tube are properly should not be altered or modifi ed in any way. connected. Air Cleaner Components AIR COOLING WARNING Hot Parts can cause severe burns.

  • Page 21: Fuel Recommendations

    ● Fuel Tank (Liquid Withdrawal) (LPG only) FUEL LINE ● Electric Lock-Off /Filter Assembly Low permeation fuel line must be installed on carbureted ● Vaporizer (LPG only) Kohler Co. engines to maintain EPA and CARB ● Regulator (Combination Primary/Secondary/Vacuum regulatory compliance. Lock-Off ) ● Carburetor ●...
  • Page 22 Fuel System IMPCO Carburetor Components WARNING Explosive Fuel can cause fi res and severe burns. If a gaseous odor is detected, ventilate area and contact an authorized service technician. LPG is extremely fl ammable and is heavier than air and tends to settle in low areas where a spark or fl ame could ignite gas.

  • Page 23: Troubleshooting Checklist

    Fuel System TROUBLESHOOTING CHECKLIST 4. Make sure ignition, governor, exhaust, throttle, and choke control systems are all operating properly. If engine starts hard, runs roughly, or stalls, check following areas. 5. Check compression. 1. Make sure LPG fuel tank is fi lled and shut-off valve If engine continues to start hard, run roughly, or stall is fully opened.
  • Page 24 Fuel System Condition Conclusion Engine stalls during operation. No fuel. Faulty lock-off or blocked fi lter. Improper governor setting. Damaged diaphragms within regulator. Vacuum line leaking, loose, or pinched. Restricted fuel line. Loose/leaking fuel enrichment hose (IMPCO carburetor system). Low power. Air cleaner or exhaust system dirty/restricted.
  • Page 25 Replace with a new 3. Install a new adapter gasket and mount air cleaner Kohler high pressure hose (LP rated) if condition is adapter onto carburetor with screws. Torque screws questionable in any way. Secure new hose using to 4.0 N·m (36 in.

  • Page 26: High Altitude Operation

    Cleaning of fi lter element is not recommended. Order 1. Throttle linkage clamp bracket should be positioned a replacement fi lter element by appropriate Kohler part on idle speed clamp bracket side of throttle shaft. number.
  • Page 27 Fuel System VAPORIZER ASSEMBLY IMPCO (Beam) Regulator Vaporizer Components Details and Components Vaporizer Fitting Elbow Outer surface of vaporizer should be kept free of dirt and debris accumulation, which will cause a loss of vaporization effi ciency. Visual inspection and necessary cleaning should be performed on a regular basis, more frequently under dusty or dirty conditions.
  • Page 28 Fuel System LPG/NG vapor enters regulator, then passes into primary Primary chamber reduces high pressure fuel fl ow from area, where pressure is reduced from up to 1724 kPa tank and vaporizer down to approximately 29 kPa (4 psi). (250 psi) at tank to 31 kPa (4.5 psi). Fuel pressure Fuel fl...
  • Page 29 Fuel System Vacuum lock-off mechanism is located in secondary chamber. When engine is running, manifold vacuum above diaphragm draws it up, so secondary valve can function normally. When engine is stopped, manifold vacuum is terminated, and diaphragm relaxes and pushes down on secondary valve lever, preventing any fuel fl...
  • Page 30 Governor System GOVERNOR These engines are equipped with an electronic governor or a mechanical governor. Governor Components H Inside Engine Throttle Lever Throttle Linkage Governor Lever Choke Linkage Governor Spring Governed Idle Spring Control Bracket Regulating Pin Locking Tab Thrust Governor Gear Governor Gear Shaft Idle Solenoid...

  • Page 31: Electronic Governor

    Governor System 4. Insert a long thin rod or tool into hole on cross shaft GCU Safety Features and rotate shaft counterclockwise (viewed from end) In event of an engine overspeed condition, GCU will shut as far as it will turn, then torque nut to 6.8 N·m down engine by grounding ignition modules.

  • Page 32: Check Oil Level

    Lubrication System This engine uses a full pressure lubrication system which 4. Reinstall dipstick and tighten securely. delivers oil under pressure to crankshaft, camshaft, CHANGE OIL AND FILTER connecting rod bearing surfaces, and hydraulic valve Change oil while engine is warm. lifters.

  • Page 33: Installation

    Lubrication System OIL SENTRY (if equipped) ™ This switch is designed to prevent engine from starting in a low oil or no oil condition. Oil Sentry may not shut ™ down a running engine before damage occurs. In some applications this switch may activate a warning signal. Read your equipment manuals for more information.

  • Page 34: Spark Plugs

    Electrical System SPARK PLUGS Inspection Inspect each spark plug as it is removed from cylinder CAUTION head. Deposits on tip are an indication of general Electrical Shock can cause injury. condition of piston rings, valves, and carburetor. Do not touch wires while engine is running. Normal and fouled plugs are shown in following photos: Normal Spark Plug Component and Details...
  • Page 35 Electrical System Carbon Fouled ELECTRONIC IGNITION SYSTEMS Ignition System Components Soft, sooty, black deposits indicate incomplete combustion caused by a restricted air cleaner, over rich Kill Switch/ carburetion, weak ignition, or poor compression. Off Position of Air Gap Key Switch Overheated Flywheel Magnet...
  • Page 36 Electrical System Wiring Diagram-15/20/25 Amp Regulated Battery Charging System with Fixed Timing KohlerEngines.com 24 690 30 Rev. G...
  • Page 37 Electrical System Fixed Ignition System This system uses a capacitive discharge (CD) coil. Ignition timing and spark remains constant regardless of engine speed. Timing of spark is controlled by location of fl ywheel magnet group as referenced to engine TDC. A typical fi xed ignition system consists of: ●...
  • Page 38 Electrical System Wiring Diagram-15/20/25 Amp Regulated Battery Charging System with Variable Ignition Timing SMART- SPARK ™ KohlerEngines.com 24 690 30 Rev. G...
  • Page 39 Electrical System Smart-Spark Advance Ignition System ™ SMART-SPARK equipped engines utilize an electronic capacitive discharge ignition system with electronic spark ™ advance. A typical application consists of following components: ● 1 magnet assembly which is permanently affi xed to fl ywheel. ●...
  • Page 40 Electrical System Wiring Diagram-15/20/25 Amp Regulated Battery Charging System with DSAI Ignition and Key Switch KohlerEngines.com 24 690 30 Rev. G...
  • Page 41 Electrical System Digital Spark Advance Ignition (DSAI) System This system uses a digital microprocessor which is located in ignition modules. Ignition timing varies depending upon engine speed with this system. There are 2 inductive-style ignition modules that control ignition timing based on engine RPM.
  • Page 42 Electrical System Wiring Diagram-3 Amp Unregulated Battery Charging System/70 Watt Lighting Optional Oil Optional Oil Ground-To-Kill Sentry Switch Sentry Switch 12 V. Battery Light Lead (White) ™ ™ (Shutdown) (Indicator Light) Optional Ground Optional Fuse Key Switch Ammeter Blue Solenoid Lights Starter Yellow...
  • Page 43 Electrical System Test for Spark NOTE: If 2 testers are available, testing can be performed simultaneously for both cylinders. However, if only 1 tester is available, 2 individual tests must be performed. Side not being tested must have spark plug lead connected or grounded.
  • Page 44 Electrical System Test Ignition Modules and Connections (Smart- Ignition Module Resistance Table Spark only) ™ 24 584 03 24 584 15-S NOTE: Resistance values apply only to modules that have been on a running engine. New service 24 584 11 24 584 36-S modules may have higher resistance until they (1 11/16 in.
  • Page 45 Electrical System Condition Possible Cause Conclusion Strong, steady spark is now present Problem should be corrected. Go to on both sides. Test SAM step 4. Still a spark problem. Test SAM. Test SAM 1. Trace red power source lead from SAM to harness connection. Separate connector and connect red lead of a DC voltmeter to harness terminal.

  • Page 46: Battery Charging System

    Electrical System To test ASAM only using 25 761 21-S tester: ● Yellow tester lead to long yellow module lead. ● Brown tester lead to long brown module lead. NOTE: SAM must be at room temperature when tested. ● Red tester lead to red module lead. Disconnect all SAM leads, isolating it from main ●...
  • Page 47 Electrical System 15/20/25 Amp Regulated Charging System Stator Stator is mounted on crankcase behind fl ywheel. Follow procedures in Disassembly and Reassembly if stator replacement is necessary. Rectifi er-Regulator NOTE: When installing rectifi er-regulator, take note of terminal markings and install plug(s) accordingly. NOTE: Disconnect all electrical connections attached to rectifi...
  • Page 48 Electrical System 15/20/25 Amp Battery Charging Systems NOTE: Always zero ohmmeter on each scale before testing to ensure accurate readings. Voltage tests should be made with engine running at 3600 RPM with no load. Battery must be good and fully charged. When problems occur in keeping battery charged or battery charges at high rate, charging system or battery might be causing problems.
  • Page 49 Electrical System 3 Amp/70 Watt Lighting Stator NOTE: Always zero ohmmeter on each scale before testing to ensure accurate readings. Voltage tests should be made with engine running at 3600 RPM with no load. Battery must be good and fully charged. To test charging system for no charge to battery: To test charging system for no lights: 1.
  • Page 50 Starter System NOTE: Do not crank engine continuously for more than 10 seconds. Allow a 60 second cool down period between starting attempts. Failure to follow these guidelines can burn out starter motor. NOTE: If engine develops suffi cient speed to disengage starter but does not keep running (a false start), engine rotation must be allowed to come to a complete stop before attempting to restart engine.
  • Page 51 4. Clean splines on drive shaft thoroughly with solvent. Dry splines thoroughly. 5. Apply a small amount of Kohler electric starter drive lubricant, to splines. Use of other lubricants may cause drive pinion to stick or bind.
  • Page 52 A brush holder tool can easily be made 5. Install thru bolts and tighten securely. from thin sheet metal. 6. Lubricate drive shaft with Kohler starter drive 1. Remove brush springs from pockets in brush holder. lubricant. Install drive components following 2.
  • Page 53 Starter System SOLENOID SHIFT ELECTRIC STARTERS Nippondenso Starters Solenoid Shift Starter Components Starter Disassembly NOTE: When removing lever and armature be careful not to lose thrust washer. 1. Disconnect lead wire from solenoid. 2. Remove nuts securing solenoid, and remove solenoid from starter assembly.
  • Page 54 Brush Replacement 4 brushes and springs are serviced as a set. Use a new Kohler brush and spring kit if replacement is necessary. 1. Perform steps 1-5 in Starter Disassembly. 2. Remove screws securing brush holder assembly to end cap (plate).
  • Page 55 Starter System 10. Starter reassembly when replacing brushes/brush Starter Reassembly holder assembly: NOTE: Always use a new retainer. Do not reuse old a. Hold starter assembly vertically on end housing, retainers that have been removed. and carefully position assembled brush holder NOTE: Correctly installed, center pivot section of drive assembly, with supplied protective tube, against lever will be fl...
  • Page 56 Starter System Solenoid Tests NOTE: DO NOT leave 12 volt test leads connected to solenoid for any time over what is necessary for performing each of individual tests. Internal damage to solenoid may occur. Disconnect all leads from solenoid including positive brush lead attached to lower stud terminal. Remove mounting hardware and separate solenoid from starter for testing.
  • Page 57 Disassembly/Inspection and Service Before working on engine or equipment, disable engine as WARNING follows: 1) Disconnect spark plug lead(s). 2) Disconnect negative (–) battery cable from battery. Accidental Starts can cause severe injury or death. Before disconnecting negative (–) ground cable, make sure all switches are OFF.
  • Page 58 Disassembly/Inspection and Service Clean all parts thoroughly as engine is disassembled. Remove LPG/NG Components Only clean parts can be accurately inspected and gauged for wear or damage. There are many commercially available cleaners that will quickly remove WARNING grease, oil, and grime from engine parts. When such a Explosive Fuel can cause fi...
  • Page 59 Disassembly/Inspection and Service Remove Throttle and Choke Controls (Mechanical Remove Carburetor (Mechanical Governor) Governor) WARNING Control Bracket Components (Mechanical Governor) Explosive Fuel can cause fi res and severe burns. If a gaseous odor is detected, ventilate area and contact an authorized service technician. LPG is extremely fl...
  • Page 60 Disassembly/Inspection and Service Remove Carburetor and Electronic Governor Remove Outer Baffl es and Blower Housing Assembly 1. Disconnect plug from rectifi er-regulator on blower housing. 2. Use tip of dipstick or a similar small fl at tool to bend locking tang, then remove B+ (center lead) from terminal plug.
  • Page 61 Disassembly/Inspection and Service Cylinder Head Components Valve Stud Gasket Spark Plug Valve Stem Seal Hydraulic Lifter Retainer Valve Spring Valve Spring Retainer Push Rod Valve Keeper Rocker Arm Rocker Arm Pivot Valve Cover O-ring Valve Cover 1. Remove screws or nuts and washers securing each Remove Valve Covers cylinder head.

  • Page 62: Exhaust Valve

    Disassembly/Inspection and Service Disassemble Cylinder Heads NOTE: These engines use valve stem seals on intake valves. Use a new seal whenever valve is removed or if seal is deteriorated in any way. Never reuse an old seal. 1. Remove screws, rocker arm pivots and rocker arms from cylinder head. Note screw color for reassembly. 2.
  • Page 63 Check base surface of hydraulic lifters for wear or damage. If lifters need to be replaced, apply a liberal Valve Guides coating of Kohler lubricant to base of each new lifter If a valve guide is worn beyond specifi cations, it will not before it is installed.
  • Page 64 2. Rotate fl ywheel so magnet is away from modules. Inspect ring gear for cracks or damage. Kohler does not provide ring gear as a serviceable part. Replace fl ywheel 3. Remove mounting screws and ignition modules.
  • Page 65 Disassembly/Inspection and Service Crankcase Components Gerotor Gears Oil Seal Closure Plate (Style A) Dipstick Tube (Style A) Oil Pick-Up Tube Oil Pump Assembly Governor Gear Shaft Governor Gear (Style A) (Style A) Camshaft Piston Pin Piston Ring Set Piston Pin Retainer Connecting Rod End Piston Connecting Rod...
  • Page 66 Disassembly/Inspection and Service Inspection Governor Gear Assembly Inspect governor gear teeth. Replace gear if it is worn, chipped, or if any teeth are missing. Inspect governor Governor Shaft Component and Details weights. They should move freely in governor gear. Disassembly NOTE: Governor gear is held onto shaft by small molded tabs in gear.
  • Page 67 Disassembly/Inspection and Service Oil Pump Assembly (Style A) Oil Pump Assembly (Style B) Oil pump is mounted inside closure plate. If service is Oil pump is mounted inside closure plate. If service is required, continue with Disassembly, Inspection, and required, continue with Disassembly, Inspection, and Reassembly.
  • Page 68 Disassembly/Inspection and Service Normally, very little wear takes place in piston boss- Remove Connecting Rods with Pistons and Rings piston pin area. If original piston and connecting rod can NOTE: If a carbon ridge is present at top of either be reused after new rings are installed, original pin can cylinder bore, use a ridge reamer tool to remove also be reused but new piston pin retainers are required.
  • Page 69 Disassembly/Inspection and Service To install new piston rings, proceed as follows: Install New Piston Rings 1. Oil control ring (bottom groove): Install expander and Piston Ring Orientation then rails. Make sure ends of expander are not overlapped. 2. Middle compression ring (center groove): Install center ring using a piston ring installation tool.
  • Page 70 Disassembly/Inspection and Service Carefully pull crankshaft from crankcase. Note thrust Connecting Rods washers and shims if used. Off set, stepped-cap connecting rods are used in all Inspect gear teeth of crankshaft. If teeth are badly worn, these engines. chipped, or some are missing, replacement of crankshaft Inspection and Service will be necessary.
  • Page 71 Install new seal to depth shown using a seal installer. NOTE: Kohler pistons are custom-machined to exacting tolerances. When oversizing a cylinder, it should Remove Flywheel End Oil Seal be machined exactly 0.25 mm (0.010 in.) or 0.50 mm (0.020 in.) over new diameter (refer to...
  • Page 72 Disassembly/Inspection and Service 4. After resizing, check bore for roundness, taper, and Measuring Piston-to-Bore Clearance size. Use an inside micrometer, telescoping gauge, Piston Detail or bore gauge to take measurements. These measurements should be taken at 3 locations in cylinder–at top, middle, and bottom. There are 2 measurements that should be taken (perpendicular to each other) at all 3 locations.
  • Page 73 Reassembly Crankcase Components Gerotor Gears Oil Seal Closure Plate (Style A) Dipstick Tube (Style A) Oil Pick-Up Tube Oil Pump Assembly Governor Gear Shaft Governor Gear (Style A) (Style A) Camshaft Piston Pin Piston Ring Set Piston Pin Retainer Connecting Rod End Piston Connecting Rod Crankshaft...
  • Page 74 Reassembly NOTE: Cylinders are numbered on crankcase. Make Install Governor Cross Shaft sure to install piston, connecting rod and end 1. Lubricate governor cross shaft bearing surfaces in cap into its appropriate cylinder bore as crankcase with engine oil. previously marked at disassembly. Do not mix end caps and connecting rods.
  • Page 75 Reassembly Determining Camshaft End Play Thrust Bearing, Washer and Shim 1. Install shim removed during disassembly onto Thrust Bearing, Washer, and Shim Sequence camshaft. 2. Position camshaft end play checking tool on camshaft. 3. Apply pressure on camshaft end play checking tool (pushing camshaft toward crankshaft).
  • Page 76 Reassembly Remove closure plate. If end play requires adjustment, Install Closure Plate Assembly remove original spacer and install appropriate size shim spacer in its place. Then follow procedure under Install Sealant Pattern and Torque Sequence Closure Plate Assembly. Install Closure Plate Oil Seal Oil Seal Depth RTV sealant is used as a gasket between closure plate and crankcase.
  • Page 77 Reassembly Flywheel/Ignition Components Debris Screen Flywheel Screw Washer Flywheel Magnet Stator Ignition Module Backing Plate Woodruff Key Spring Washer Spacer Metal Debris Screen Ring Support Metal Debris Screen Washer Assembly NOTE: Make sure fl ywheel key is installed properly in Install Stator and Backing Plates keyway.
  • Page 78 Reassembly Install Plastic Debris Screen Install Supports for Metal Debris Screen 1. If a metal debris screen is used, with threaded CAUTION individual supports, install a spacer washer on external threads. Apply Loctite (removable) ® ® Failure to utilize or reassemble debris screen onto threads.
  • Page 79 Reassembly b. Thread opposite end of stud with preapplied Assemble Cylinder Heads locking compound into crankcase until specifi ed Prior to installation, lubricate all components with engine height from crankcase surface is achieved. oil, paying particular attention to lip of valve stem seal, When threading in studs, use a steady tightening valve stems and valve guides.
  • Page 80 Reassembly Install Spark Plugs Install Intake Manifold 1. Check gap using wire feeler gauge. Adjust gap to Torque Sequence 0.76 mm (0.030 in.) for all except NG with CD fi xed timing or 0.51 mm (0.020 in.) for NG with CD fi xed timing.
  • Page 81 Reassembly External Engine Components Vaporizer Lock-off /Filter Regulator Carburetor Gasket Intake Manifold Plastic Intake Manifold Outer Baffl e Inner Baffl e Breather Reed Breather Gasket Breather Cover Breather Tube Oil Sentry Filter Air Cleaner ™ Oil Filter Nipple Oil Cooler Electric Starter Lifting Bracket Fixed Guard...
  • Page 82 Reassembly 3. Position outer baffl es and loosely start mounting Install Breather Cover and Inner Baffl es screws. M6 screws go into back of cylinders. Short Breather Cover Details and Torque Sequence M5 screws go into lower holes closest to blower housing.
  • Page 83 Reassembly 3. Reconnect fuel hose to carburetor fi tting and secure Install Carburetor (Mechanical Governor) hose clamp. 4. Reconnect throttle linkage in carburetor throttle lever WARNING and secure with bushing. Explosive Fuel can cause fi res and severe 5. Position electronic governor assembly on crankcase burns.
  • Page 84 Reassembly Control Bracket Components (Mechanical Governor Lever Hole Position (6 mm) Governor) Governor Lever Governed Idle Hole Hole 1 Hole 2 Hole 3 Hole 4 Hole 5 Hole 6 6 mm Governor Lever and Hole Position/RPM Chart Choke Linkage Control Bracket Governor Gov.
  • Page 85 Reassembly Governor Lever Hole Position (8 mm) Install Oil Sentry (if equipped) ™ 1. Apply pipe sealant with Tefl on (Loctite 592™ ® ® ® Thread Sealant or equivalent) to threads of Oil Sentry switch and install it into breather cover. ™...
  • Page 86 Reassembly Torque Specifi cations-Covers Install Valve Covers Gasket/RTV 3.4 N·m (30 in. lb.) Torque Sequence Black O-ring w/shoulder screws 5.6 N·m (50 in. lb.) w/screws and spacers 9.9 N·m (88 in. lb.) Yellow or Brown O-ring w/integral spacers 9.0 N·m (80 in. lb.) Install Air Cleaner Assembly NOTE: Route fuel line in contour to avoid restriction.
  • Page 87 Reassembly Install Oil Filter and Fill Crankcase with Oil NOTE: Make sure both oil drain plugs are installed and torqued to specifi cations to prevent oil leakage. 1. Install oil drain plug(s). Torque plug(s) to 13.6 N·m (10 ft. lb.). If oil drain valve is used, make sure valve body is closed and cap is on.
  • Page 88 © 2021 by Kohler Co. All rights reserved. KohlerEngines.com 24 690 30 Rev. G...

This manual is also suitable for:

Command ch18Command ch23Command ch25Command ch640Command ch730Command ch740

Table of Contents