Kohler CH-11-16, Service Manual

Page 1: ...SERVICE MANUAL HORIZONTAL CRANKSHAFT COMMAND CH11 16 ...

Page 2: ...ting Section 4 Air Cleaner and Air Intake System Section 5 Fuel System and Governor Section 6 Lubrication System Section 7 Retractable Starter Section 8 Electrical System and Components Section 9 Disassembly Section 10 Inspection and Reconditioning Section 11 Reassembly 1 2 3 4 5 6 7 8 9 10 11 ...

Page 3: ... follow these precautions could result in injury to yourself and others Rotating Parts Keep hands feet hair and clothing away from all moving parts to prevent injury Never operate the engine with covers shrouds or guards removed Hot Parts Engine components can get extremely hot from operation To prevent severe burns do not touch these areas while the engine is running or immediately after it is tu...

Page 4: ...ated 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 in contact with hot parts or sparks from ignition Do not start the engine near spilled fuel Never use gasoline as a cleaning agent Flammable Solvents Carburetor cleaners and solvents are extremely flammable Keep sparks flames and other source...

Page 5: ...del No Command Engine Horizontal Crankshaft Horsepower 11 11 HP 12 5 12 5 HP 13 13 HP 14 14 HP 15 15 HP 16 16 HP Version Code S Electric Start T Retractable Start ST Electric Retractable Start GT Generator Application Retractable Start GS Generator Application Electric Start PT Pump Retractable Start RT Gear Reduction Retractable Start C H 12 5 ST Factory Code C Serial No Year Manufactured Code Co...

Page 6: ...near spilled fuel Never use gasoline as a cleaning agent General Recommendations Purchase gasoline in small quantities and store in clean approved containers A container with a capacity of 2 gallons or less with a pouring spout is recommended Such a container is easier to handle and helps eliminate spilling during refueling Do not use gasoline left over from the previous season to minimize gum dep...

Page 7: ... hole with your thumb and turn the engine over until the piston is at the top of its stroke Pressure against thumb is greatest Reinstall the plug but do not connect the plug lead 6 Store the engine in a clean dry place Maintenance Schedule The following required maintenance procedures should be performed at the frequency stated in the table and should also be included as part of any seasonal tune ...

Page 8: ...1 6 Section 1 Safety and General Information Figure 1 4 Typical Engine Dimensions Dimensions in millimeters Inch equivalents shown in ...

Page 9: ...11 CH12 5 CH13 CH14 398 cc 24 3 cu in CH15 CH16 426 cc 26 0 cu in Compression Ratio 8 5 1 Weight 40 kg 88 3 lb Max Oil Capacity w filter 1 9 L 2 0 qt Lubrication full pressure w full flow filter Air Cleaner Base Nut Torque 9 9 N m 88 in lb Angle of Operation Maximum at full oil level Intermittent All Directions 35 Continuous All Directions 25 Balance Shaft End Play Free 0 0575 0 3625 mm 0 0023 0 0...

Page 10: ...y Pressure Switch Torque 6 8 N m 60 in lb Oil Pump Cover Fastener Torque 4 0 6 2 N m 35 55 in lb Connecting Rod Cap Fastener Torque 6 mm straight shank bolt 11 3 N m 100 in lb 8 mm straight shank bolt 22 6 N m 200 in lb 8 mm step down type bolt 14 7 N m 130 in lb Connecting Rod to Crankpin Running Clearance at 21 C 70 F New 0 030 0 055 mm 0 0012 0 0022 in Max Wear Limit 0 07 mm 0 0025 in Connectin...

Page 11: ...No Sleeve Bearing Max Wear Limit 42 015 mm 1 6541 in Crankshaft Bore In Closure Plate to Crankshaft Running Clearance New Sleeve Bearing 0 025 0 1200 mm 0 00098 0 00472 in Parent Material No Sleeve Bearing 0 030 0 0880 mm 0 0011 0 0034 in Flywheel End Main Bearing Journal O D New 44 913 44 935 mm 1 7682 1 7691 in O D Max Wear Limit 44 84 mm 1 765 in Max Taper 0 022 mm 0 0009 in Max Out of Round 0 ...

Page 12: ... 2 5 3 3 N m 22 29 in lb Solenoid Starter Mounting Hardware Torque Nippondenso Starter 6 0 9 0 N m 53 79 in lb Delco Remy Starter 4 0 6 0 N m 35 53 in lb Nut Positive Brush Lead Torque Nippondenso Starter 8 0 12 0 N m 71 106 in lb Delco Remy Starter 6 0 9 0 N m 53 79 in lb Fan Flywheel Fan Fastener Torque 9 9 N m 88 in lb Flywheel Retaining Screw Torque 66 4 N m 49 ft lb Fuel Pump Fuel Pump Cover ...

Page 13: ...n Top Compression Ring to Groove Side Clearance CH11 14 0 040 0 105 mm 0 0016 0 0041 in CH15 CH16 0 060 0 105 mm 0 0023 0 0041 in Middle Compression Ring to Groove Side Clearance CH11 14 0 040 0 072 mm 0 0016 0 0028 in CH15 CH16 0 040 0 085 mm 0 0015 0 0002 in Oil Control Ring to Groove Side Clearance CH11 14 0 551 0 675 mm 0 0217 0 0266 in CH15 CH16 0 176 0 026 0 0069 0 0010 in Top and Center Com...

Page 14: ...and Valve Lifters Hydraulic Valve Lifter to Crankcase Running Clearance 0 0124 0 0501 mm 0 0005 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 New 7 038 7 058 mm 0 2771 0 2779 in Max Wear Limit 7 134 mm 0 2809 in Exhaust Valve Guide I D New 7 038 ...

Page 15: ...7 47 5 35 82 7 61 116 6 86 139 7 103 61 0 45 M14 58 3 43 76 4 55 131 5 97 184 4 136 219 7 162 94 9 70 Noncritical Fasteners Into Aluminum Noncritical Fasteners Into Aluminum Tightening Torque N m in lb or 10 Property Class N m in lb x 0 113 N m ft lb x 1 356 in lb N m x 8 85 ft lb N m x 0 737 Torque Conversions 4 8 5 8 8 8 10 9 12 9 4 8 5 8 8 8 10 9 12 9 Oil Drain Plugs Tightening Torque N m Engli...

Page 16: ... e h c r o F 5 0 4 2 8 R L K s l o o T E S r e t s e T n w o d k a e L r e d n i l y C n r o w e r a s e v l a v r o s g n i r n o t s i p r e d n i l y c f i d n a n o i t n e t e r n o i t s u b m o c g n i k c e h c r o F S 5 0 1 6 7 5 2 r e l h o K e r a w t f o S c i t s o n g a i D I F E n o i t c e j n I l e u F c i n o r t c e l E C P p o t k s e D r o p o t p a L h t i w e s U S 3 2 1 6 7...

Page 17: ...M A S e l u d o M e c n a v d A k r a p S K R A P S T R A M S h t i w s e n i g n e n o M A S D d n a M A S A M A S e h t t s e t o T S 0 4 1 6 7 5 2 r e l h o K t f i h S d i o n e l o S l o o T g n i d l o H h s u r B r e t r a t S g n i c i v r e s g n i r u d s e h s u r b d l o h o T 6 1 4 2 8 R L K s l o o T E S e v i r D a i t r e n I l o o T g n i R g n i n i a t e R r e t r a t S s r e t ...

Page 18: ...c e l E t f i h S d i o n e l o S S 2 0 7 5 3 2 5 r e l h o K t n a l a e S e n o c i l i S V T R e t i t c o L r e s n e p s i d l o s o r e a z o 4 n i y d o B y v a e H 0 0 9 5 e s u r o f d e v o r p p a e r a d e t s i l e s o h t s a h c u s s t n a l a e s V T R t n a t s i s e r l i o d e s a b e m i x o y l n O e t i t c o L s c i t s i r e t c a r a h c g n i l a e s t s e b r o f d e d ...

Page 19: ...ing or removing with a puller Figure 2 1 Flywheel Holding Tool Rocker Arm Crankshaft Tool A spanner wrench to lift the rocker arms or turn the crankshaft may be made out of an old junk connecting rod 1 Find a used connecting rod from a 10 HP or larger engine Remove and discard the rod cap 2 Remove the studs of a Posi Lock rod or grind off the aligning steps of a Command rod so the joint surface is...

Page 20: ...n the fuel system 3 Clogged fuel line 4 Loose or faulty wires or connections 5 Faulty choke or throttle controls cables 6 Faulty spark plug 7 Low compression 8 Faulty Automatic Compression Release ACR mechanism Engine Will Not Crank 1 Hydrostatic transmission not in neutral PTO drive is engaged 2 Battery is discharged 3 Safety interlock switch is engaged 4 Loose or faulty wires or connections 5 Fa...

Page 21: ...ook for holes tears cracked or damaged sealing surfaces or other damage that could allow unfiltered air into the engine Also note if the element is dirty or clogged These could indicate that the engine has been underserviced Check the carburetor throat for dirt Dirt in the throat is further indication that the air cleaner is not functioning properly Check that the oil level is within the operating...

Page 22: ...assembled breather can cause oil to be forced out at oil seals gaskets or other available spots Crankcase vacuum is best measured with a water manometer or vacuum pressure test gauge See Section 2 Complete instructions are provided with the testers Test the crankcase vacuum with the manometer as follows 1 Insert the rubber stopper into the oil fill hole Be sure the pinch clamp is installed on the ...

Page 23: ...e you can use a breaker bar and socket on the flywheel nut screw to hold it in position You may need an assistant to hold the breaker bar during testing If the engine is mounted in a piece of equipment you may be able to hold it by clamping or wedging a driven component Just be certain that the engine cannot rotate off of TDC in either direction 4 Install the adapter into the spark plug hole but d...

Page 24: ...precleaner every 25 hours of operation more often under extremely dusty or dirty conditions To service the precleaner perform the following steps 1 Loosen the cover retaining knob and remove the cover 2 Remove the foam precleaner from the paper air cleaner element 3 Wash the precleaner in warm water with detergent Rinse the precleaner thoroughly until all traces of detergent are eliminated Squeeze...

Page 25: ...aner base and valve cover Disassembly The following procedure is for complete disassembly of all air cleaner components 1 Loosen the air cleaner cover retaining knob and remove the air cleaner cover 2 Remove the wing nut element cover and air cleaner element 3 If so equipped remove the precleaner from the paper element 4 Disconnect the breather hose from the valve cover 5 Remove the air cleaner ba...

Page 26: ...rburetor float bowl and is moved into the carburetor body There the fuel is mixed with air This fuel air mixture is then burned in the engine combustion chamber Fuel Filter Most engines are equipped with an in line fuel filter Periodically inspect the filter and replace with a genuine Kohler filter every 200 operating hours Fuel Line In compliance with CARB Tier III Emission Regulations these engi...

Page 27: ...gine several times and observe flow 2 If there is fuel at the tip of the spark plug fuel is reaching the combustion chamber If there is no fuel at the tip of the spark plug check for fuel flow from the fuel tank Test 3 3 If fuel does flow from the line check for faulty fuel pump Test 4 If fuel does not flow from the line check for clogged fuel tank vent fuel pick up screen in line filter shut off ...

Page 28: ...nap ring included with the new fuel pump kit that will serve as a tool for this purpose a Note the direction arrows molded into the pump housing and position the snap ring so the ends depress the two square release tabs at the inlet end See Figure 5 3 Figure 5 3 b Lubricate the O Ring on each fitting with oil c Insert the 90 fitting until the toothed flange is just outside of the pump body Rotate ...

Page 29: ...on the idle fuel adjusting needle Troubleshooting If engine troubles are experienced that appear to be fuel system related 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 operating properly Make sure fuel is reaching the carburetor This includes chec...

Page 30: ...body d Dirt under the fuel inlet needle Remove needle clean needle and seat and blow with compressed air e Air filter dirty or restricted f Bowl vent or air bleeds plugged Remove fuel bowl low idle fuel adjusting needle not on all models and welch plugs Clean vent ports passages and air bleeds Blow out all passages with clean compressed air g Leaky cracked or damaged float Submerge float to check ...

Page 31: ...sition Set the low idle speed to 1500 RPM 75RPM by turning the low idle speed adjusting screw in or out Check the speed using a tachometer NOTE The actual low idle speed depends on the application refer to equipment manufacture s recommendations The recommended low idle speed for basic engines is 1500 RPM Low Idle Fuel Needle with Limiter Cap Adjustment Some emission compliant carburetors have a l...

Page 32: ...sition If possible place the engine under load Turn the high idle fuel adjusting needle in slowly until engine speed decreases and then back out approximately 1 4 turn for best high speed performance 5 Low Idle Speed Setting Place the throttle control into the idle or slow position Set the low idle speed to 1500 RPM 75 RPM by turning the low idle speed adjusting screw in or out Check the speed usi...

Page 33: ...placed Figure 5 8 Adjustable Main Jet Carburetor Exploded View Disassembly 1 Remove the power screw needle and spring main jet power screw gasket and fuel bowl 2 Remove the bowl gasket float shaft float and fuel inlet needle Throttle Lever and Shaft Choke Lever and Shaft Choke Plate Float Float Shaft Bowl Gasket Fuel Bowl Bowl Retaining Screw Bowl Retaining Screw Fuel Inlet Needle Fuel Inlet Seat ...

Page 34: ...mbly See Figure 5 10 Also take note of the choke plate position in bore and the position of the choke lever and choke return spring Figure 5 10 Marking Choke Plate and Carburetor Body 2 Grasp the choke plate with a pliers Pull it out of the slot in the choke shaft See Figure 5 11 Figure 5 11 Removing Choke Plate 3 Remove the choke shaft and choke return spring Throttle Shaft Removal 1 Because the ...

Page 35: ...spection Carefully inspect all components and replace those that are worn or damaged Inspect the carburetor body for cracks holes and other wear or damage Inspect the float for cracks holes and missing or damaged float tabs Check the float hinge and shaft for wear or damage Inspect the fuel inlet needle and seat for wear or damage Inspect the tip of the low idle fuel adjusting needle and power scr...

Page 36: ...install new plugs as follows 1 Position the carburetor body with the welch plug cavity to the top 2 Place a new welch plug into the cavity with the raised surface up 3 Use the end of the tool that is about the same size as the plug and flatten the plug Do not force the plug below the surface of the cavity See Figure 5 13 4 After the plug is installed seal it with glyptal or an equivalent sealant A...

Page 37: ...ple test made with the engine off that can determine if the solenoid is functioning properly Use a separate switched 12 volt power supply to test 1 Shut off the fuel and remove the solenoid from the carburetor When the solenoid is loosened and removed gas will leak out of the carburetor Have a container ready to catch the fuel 2 Blow clean off solenoid using clean compressed air CAUTION Do this te...

Page 38: ...e To align choke plate insert a 0 010 in shim between the top right edge of the choke plate and bore See Figure 5 17 Then while pushing down on the top of the choke shaft tighten screws securely Figure 5 17 Measuring Clearance Air Cleaner Removed For Clarity 5 Check choke shaft and choke plate for freedom of movement by performing the following a Using the choke lever close the choke plate The cho...

Page 39: ...nt Make this initial adjustment whenever the governor arm is loosened or removed from the cross shaft To ensure proper setting make sure the throttle linkage is connected to the governor arm and the throttle lever on the carburetor The carburetor and air cleaner should be positively secured on the mounting studs eliminating any possible movement when adjustment is being made See Figure 5 18 1 Pull...

Page 40: ...rly seat a new or rebuilt engine should be operated for at least 50 hours using standard petroleum based oil before switching to synthetic oil A logo or symbol on oil containers identifies the API service class and SAE viscosity grade Figure 6 1 Oil Container Logo Check Oil Level 1 Make sure the engine is stopped level and is cool so the oil has had time to drain into the sump 2 To keep dirt grass...

Page 41: ...ation Refill with service class SG SH SJ or higher oil as specified in the Viscosity Grades table Change the oil as follows 1 Run engine until warm 2 Remove the oil drain plug and oil fill cap dipstick Be sure to allow ample time for complete drainage 3 Make sure the engine is level when filling checking and changing the oil 4 Reinstall the drain plug Make sure it is tightened to7 3 9 0 N m 65 80 ...

Page 42: ...sure Lubrication System Operation This engine uses a full pressure lubrication system that delivers oil under pressure to the crankshaft camshaft balance shaft and connecting rod bearing surfaces In addition to lubricating the bearing surfaces the lubrication system operates the hydraulic valve lifters A high efficiency Gerotor oil pump is located in the closure plate and is driven directly by the...

Page 43: ...oil plug hole To add oil remove the vented plug at the top of the unit Use AGMA No 7 EP oil in the reduction gear unit Following are a few products that meet this spec Mobilgear 634 Pennzoil Super Maxol S Pennzoil Maxol EP Gear Oil Pennzoil Super Maxol EP Gear Oil Pennzoil Super Pennztac EP Gear Oil Figure 6 9 New Relief Valve Oil Sentry Oil Pressure Monitor Some engines are equipped with an optio...

Page 44: ... five hex flange screws to the blower housing Leave the screws slightly loose 2 Pull the starter handle out until the pawls engage in the drive cup Hold the handle in this position and tighten the screws securely See Figure 7 2 Figure 7 2 Removing Retractable Starter Rope Replacement The rope can be replaced without complete starter disassembly 1 Remove the starter from the engine blower housing 2...

Page 45: ... pulley 8 Rotate the pulley clockwise until the rope hole in pulley is aligned with rope guide bushing of starter housing NOTE Do not allow the pulley spring to unwind Use a C clamp to hold the pulley in position 9 Insert the new rope through the rope hole in starter pulley and rope guide bushing of housing See Figure 7 4 Figure 7 4 Installing Rope 10 Tie a slip knot approximately 12 from the free...

Page 46: ...ly in the pulley See Figure 7 8 Rope Hole in Pulley Outer Spring Hook Spring Keeper Figure 7 8 Position of Spring and Keeper in Pulley 10 Remove the spring and keeper assembly from the pulley as a package CAUTION Spring Under Tension Do not remove the spring from the keeper Severe personal injury could result from the sudden uncoiling of the spring Inspection and Service 1 Carefully inspect the ro...

Page 47: ...Apply a small amount of Loctite No 271 to the threads of the center screw Install the center screw with washer and retainer to the center shaft Torque the screw to 7 4 8 5 N m 65 75 in lb 8 Tension the spring and install the rope and handle as instructed in steps 6 through 12 under Rope Replacement 9 Install the starter to the engine blower housing See Figure 7 11 Figure 7 9 Installing Pulley and ...

Page 48: ... standard spark plug is a Champion RC12YC Kohler Part No 12 132 02 S A high performance spark plug Champion Platinum 3071 used on Pro Series engines Kohler Part No 25 132 12 S is also available Equivalent alternate brand plugs can also be used Gap CH11 15 1 02 mm 0 040 in CH16 0 76 mm 0 030 in Thread Size 14 mm Reach 19 1 mm 3 4 in Hex Size 15 9 mm 5 8 in Spark Plug Service Service the spark plug ...

Page 49: ...k deposits indicate incomplete combustion Incomplete combustion is usually caused by overrich carburetion weak ignition or poor compression Worn On a worn plug the center electrode will be rounded and the gap will be eroded 010 or more than the correct gap Wet Fouled A wet plug is caused by excess fuel or oil in the combustion chamber Excess fuel could be caused by operating the engine with too mu...

Page 50: ...children Remove all jewelry when servicingbatteries Before disconnecting the negative ground cable make sure all switches are OFF If ON a spark will occur at the ground cable terminal which could cause an explosion if hydrogen gas or gasoline vapors are present 1 Regularly check the level of electrolyte Add distilled water as necessary to maintain the recommended level NOTE Do not overfill the bat...

Page 51: ...onic Magneto Ignition System CH11 15 Engines Operation As the flywheel rotates and the magnet assembly moves past the ignition module a low voltage is induced in the primary windings of the module When the primary voltage is precisely at its peak the module induces a high voltage in its secondary windings This high voltage creates a spark at the tip of the spark plug This spark ignites the fuel ai...

Page 52: ...and audible sparks should be produced 4 If the resistance is low or 0 ohms the module secondary is shorted Replace the module If the resistance is high or infinity ohms the module secondary is open Replace the module If the resistance is within the specified range the module secondary is OK 3 If visible and audible sparks are produced the ignition module is OK If visible and audible sparks are not...

Page 53: ...circuit shapes this pulse putting it in a useable form for the other circuits The conditioned pulse starts the charge pump which charges a capacitor in linear fashion directly related to engine speed The pulse also resets the delay circuit The comparator is off during this period When the flywheel magnet group has passed the input coil and the original pulse drops back to zero the capacitor in the...

Page 54: ...ion is provided to help you get to the root of a reported problem Reported ignition problems are most often due to poor connections Before beginning the test procedure check all external wiring Be certain all ignition related wires are connected including the spark plug lead Be certain all terminal connections fit snugly Make sure the ignition switch is in the run position NOTE The CD ignition sys...

Page 55: ...dvance module SAM is getting proper voltage a Return to the connector where the engine and unit wiring harnesses are joined and find the double red lead in the back of the engine connector Using a DC voltmeter with a probe lead test the voltage at the terminal on the double red lead with the key switch in both the start and run positions At least 7 2 volts must be present If voltage is low proceed...

Page 56: ...g on the equipment powered by the engine Also disconnect other electrical accessories in common ground with the engine 3 Prevent the stator AC leads from touching or shorting while the engine is running This could damage the stator Electric Start Engines 15 20 amp Battery Charging System Ground to Kill Lead White Violet Blue Red S B R A M GND Keyswitch Optional Oil Sentry Switch Indicator Light Op...

Page 57: ...he battery terminals 3a With the engine stopped measure the resistance across stator leads using an ohmmeter 3b With the engine stopped measure the resistance from each stator lead to ground using an ohmmeter 1 With the engine running at 3600 RPM measure the voltage from B lead to ground using a DC voltmeter Conclusion 1 If the charge rate increases when load is applied the charging system is OK a...

Page 58: ...mage the ceramic permanent magnets inside the starter frame Starter Removal and Installation Refer to the Disassembly and Reassembly sections for starter removal and installation procedures Inertia Drive Electric Starter This subsection covers the operation troubleshooting and repair of the inertia drive permanent magnet electric starter Troubleshooting Guide Problem Starter Does Not Energize Star...

Page 59: ...ive components Style A Drive Service 1 Remove the starter from the engine and remove the dust cover 2 Hold the drive pinion in a vice with soft jaws when removing and installing the stop nut The armature will rotate with the nut until the drive pinion stops against internal spacers NOTE Do not overtighten the vise as this can distort the drive pinion 3 Remove the stop nut stop gear spacer anti dri...

Page 60: ... Drive Components Bonded Inertia Drive Starter 2 Disassemble the snap ring removal tool see Section 2 3 Again referring to Figure 8 11 grasp the spring retainer and push it toward the starter compressing the anti drift spring and exposing the retaining ring 4 Holding the spring retainer in the retracted position assemble the inner halves of the removal tool around the armature shaft with the retai...

Page 61: ...h Style A commutator end caps it will be aligned with a premarked line on the starter frame The frame is not premarked on starters with Style B end caps Place a piece of masking tape on the frame and mark a line on the tape in line with the raised line on the end cap See Figure 8 17 3 Remove the thru bolts 4 Remove the commutator end cap with brushes and brush springs Style A Style B end caps remo...

Page 62: ...Tapping Screw Brush Springs Under Brushes 1 3 4 Sheet Metal Brush Holder Tool Brush Holder Tool Installed Over Brushes and End Cap 1 2 1 2 1 2 Figure 8 16 Brush Holder Tool Style A End Cap Style B End Cap Brush Replacement Starters with Style B end caps have the brushes in a plastic carrier housing separate from the end cap Replacement brushes come preassembled in the carrier housing retained with...

Page 63: ...he engine When the engine starts and the start switch is released the starter solenoid is deactivated the drive lever moves back and the drive pinion moves out of mesh with the ring gear into the retracted position Starter Disassembly 1 Disconnect the wire from the solenoid 2 Remove the hex nuts securing the solenoid and remove the solenoid from the starter assembly 3 Remove the two thru bolts 4 R...

Page 64: ...rush holder to keep the springs from popping out Starter Service Clean drive lever and armature shaft Apply Kohler electric starter drive lubricant See Section 2 to lever and shaft Starter Reassembly 1 Install the drive pinion onto the armature shaft 2 Slide the stop collar onto the armature shaft below the retaining ring groove Make sure the recessed side of the stop collar is up 3 Position a new...

Page 65: ...drive end cap aligning the cutout with lever section on top The rubber insulating grommet should also be up See Figure 8 25 NOTE Maintain pressure on the insulator while installing so the springs do not come out Figure 8 25 Installing Frame with Brush Plate Assembly 11 Remove the tool and install the commutator end cap aligning the cutout with the insulating grommet See Figure 8 26 Figure 8 26 Ins...

Page 66: ...ing the solenoid to the starter See Figure 8 30 Figure 8 30 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 was mounted with external Torx head screws the plunger is part of the solenoid unhook the plunger pin from the drive lever Remove the gasket from the recess in the housing See Fig...

Page 67: ...side the commutator end See Figure 8 34 Figure 8 34 Removing Commutator End Plate Assembly 6 Remove the frame from the armature and drive end cap See Figure 8 35 Figure 8 35 Starter Frame Removed 7 Remove the drive lever pivot bushing and backing plate from the end cap See Figure 8 36 Figure 8 36 Removing Pivot Bushing and Backing Plate 8 Take out the drive lever and pull the armature out from the...

Page 68: ...nd Springs Inspect both the springs and brushes for wear fatigue or damage Measure the length of each brush The minimum length for each brush is 7 6 mm 0 300 in See Figure 8 40 Replace the brushes if they are worn undersize or their condition is questionable Figure 8 40 Brush Checking Armature 1 Clean and inspect the commutator outer surface The mica insulation of the commutator must be lower than...

Page 69: ... set 4 Use Brush and Spring Kit Kohler Part No 52 221 01 S if replacement is necessary 1 Perform steps 1 5 in Starter Disassembly Commutator O D Mica Insulation 2 Remove the two screws securing the brush holder assembly to the end cap plate Note the orientation for reassembly later See Figure 8 43 Discard the old brush holder assembly Figure 8 43 Removing Brush Holder 3 Clean the component parts a...

Page 70: ... Install the stop collar down onto the armature shaft with the counter bore recess up b Install a new retainer in the larger rear groove of the armature shaft Squeeze with a pliers to compress it in the groove c Slide the stop collar up and lock it into place so the recess surrounds the retainer in the groove If necessary rotate the pinion outward on the armature splines against the retainer to he...

Page 71: ...mounting screw holes in the metal clips must be up out Slide the brush holder assembly down into place around the commutator and install the positive brush lead grommet in the cutout of the frame See Figure 8 51 Save the protective tube it may be used for future servicing Figure 8 51 Installing Brush Holder Assembly with Supplied Tube Starter reassembly when not replacing the Brushes Brush Holder ...

Page 72: ...met of the positive brush lead 12 Install the two thru bolts and the two brush holder mounting screws Torque the thru bolts to 5 6 9 0 N m 49 79 in lb Torque the brush holder mounting screws to 2 5 3 3 N m 22 29 in lb See Figures 8 55 and 8 56 Figure 8 55 Torquing Thru Bolts Figure 8 56 Torquing Brush Holder Screws 13 Hook the plunger behind the upper end of the drive lever and install the spring ...

Page 73: ...Plunger Actuation Test 2 Solenoid Pull In Coil Contact Continuity Test 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 1 and check for continuity See Figure 8 59 The ohmmeter should indicate continuity if no continuity is indicated the solenoid should be replaced Repeat test several times to confirm cond...

Page 74: ...hmmeter leads to the two large post terminals Perform the preceding test 3 and check for continuity See Figure 8 61 The meter should indicate continuity if no continuity is indicated the solenoid should be replaced Repeat test several times to confirm condition Figure 8 61 Testing Hold In Coil Solenoid Contact Continuity Plunger Pushed In VOM Meter Leads 12 volt Test Leads ...

Page 75: ...rter 11 Remove rectifier regulator 12 Remove Oil Sentry 13 Remove valve cover 14 Remove cylinder head baffle 15 Remove blower housing and baffles 16 Remove carburetor adapter and heat deflector 17 Remove ignition module 18 Remove fuel line 19 Remove cylinder head push rods and gasket 20 Remove drive cup grass screen flywheel and fan 21 Remove stator and wiring harness 22 Remove closure plate 23 Re...

Page 76: ...Remove the two hex flange nuts from the exhaust port studs and take off the exhaust inlet pipe and gasket Figure 9 2 Removing Muffler Figure 9 3 Removing Muffler Figure 9 4 Removing Air Cleaner Cover 2 Remove the wing nut washer element cover element and precleaner See Figure 9 5 Figure 9 5 Removing Air Cleaner Elements Muffler Hex Flange Screws Upper Muffler Bracket Lower Mounting Bracket Hex Fla...

Page 77: ...vernor spring hole location and unhook the spring from the lever of the throttle control bracket See Figure 9 8 and 9 9 Figure 9 6 Removing Spitback Cup and Air Cleaner Base 4 Loosen the hose clamp and disconnect the breather hose from the rocker arm cover Remove the air cleaner base from the studs and disconnect the choke linkage from the carburetor choke lever See Figure 9 7 Figure 9 8 Removing ...

Page 78: ...ver Remove Fuel Tank WARNING Explosive Fuel Gasoline may be present in the carburetor and fuel system Gasoline is extremely flammable and its vapors can explode if ignited Keep sparks open flames and other sources of ignition away from the engine 1 Turn fuel shut off valve to OFF horizontal position Disconnect fuel line from valve 2 Remove hex flange nuts from lower bracket and hex flange screws f...

Page 79: ...n of spacer washer behind bracket on lower screw See Figure 9 15 b Remove the screws securing the starter pinion cover to the blower housing See Figure 9 16 Figure 9 14 Removing Fuel Pump Remove Electric Starter Electric Starter Bendix Drive or Solenoid Shift 1 Disconnect the lead connected to the stud terminal on the starter or both leads from the solenoid on solenoid shift starters Figure 9 16 R...

Page 80: ...See Figure 9 21 Figure 9 19 Starter Mounted With Bolts Remove Rectifier Regulator 1 Remove the connector s from the rectifier regulator See Figure 9 20 2 Remove the two hex flange screws securing the rectifier regulator and the attached ground lead non metal blower housing only d If removal of the mounting studs is required use the two hex flange nuts from the mounting studs tightened flange to fl...

Page 81: ...e Blower Housing and Baffles 1 Remove the hex flange screws from the blower housing and baffles Disconnect the wire harness from the key switch if equipped Remove the blower housing intake tube and baffles See Figures 9 24 9 25 and 9 26 Figure 9 22 Removing Valve Cover Remove Cylinder Head Baffle 1 Remove the hex flange screws securing the cylinder head baffle to the cylinder head See Figure 9 23 ...

Page 82: ...om ignition module 3 Remove the two hex flange screws and ignition module Figure 9 29 Removing Fuel Line Remove Cylinder Head 1 Remove the hex flange screws spacer from the screw by the exhaust port cylinder head push rods and cylinder head gasket See Figures 9 30 and 9 31 Mark the push rods for reassembly Discard the screws Do not reuse Figure 9 28 Removing Ignition Module Remove Fuel Line 1 Remo...

Page 83: ...idge arrangement as shown in Figure 9 33 The second type uses individually mounted rocker arm assemblies with or without a guide plate rather than a bridge This type is shown in Figure 9 32 Components are unique to each style of head Follow the appropriate procedure based upon the type of head configuration involved NOTE Before disassembly mark all valve train components to assure they are reassem...

Page 84: ...c start only On these models the grass screen must be removed first to access the hex flange screw and washer 2 Unsnap and remove the grass screen from the fan 3 Remove the flywheel from the crankshaft using a puller See Figure 9 38 Figure 9 37 Removing Flywheel Retaining Screw and Drive Cup Figure 9 38 Removing Flywheel With a Puller 4 Remove the four hex flange screws and fan from flywheel See F...

Page 85: ...Pickup Oil Pressure Relief Valve Oil Pump and Oil Seal 1 Remove the oil seal from the closure plate See Figure 9 43 2 Remove the hex flange screw clip oil pickup and O Ring seal 3 Identify the type of oil pressure relief valve used If the relief valve assembly is like that shown in Figure 9 44 remove the hex socket screw retaining bracket valve body piston and spring If the relief valve is like th...

Page 86: ...ving Camshaft 2 Mark or identify the hydraulic lifters as either intake or exhaust See Figure 9 48 Remove the lifters from the crankcase NOTE The intake hydraulic lifter is farthest from the crankcase gasket surface The exhaust hydraulic lifter is nearest to the crankcase gasket surface Figure 9 46 Removing Oil Pump Oil Pump Cover Hex Flange Screws Oil Pump Rotors O Ring Figure 9 48 Identifying Hy...

Page 87: ...he piston away from the crankshaft and out of the cylinder bore Figure 9 50 Removing Connecting Rod Remove Piston From Connecting Rod 1 Remove the wrist pin retainer and wrist pin Separate the piston from the connecting rod See Figure 9 51 Figure 9 51 Removing Piston From Connecting Rod Remove Piston Rings 1 Remove the top and center compression rings using a ring expander tool See Figure 9 52 Fig...

Page 88: ...Governor Cross Shaft 3 Remove the governor cross shaft oil seal from the crankcase See Figure 9 55 Figure 9 55 Removing Cross Shaft Oil Seal 4 If necessary remove the governor gear and regulating pin See Figure 9 56 Cross Shaft Oil Seal Figure 9 56 Removing Governor Gear NOTE The governor gear is held onto the governor gear shaft by small molded tabs in the gear When the gear is removed from the s...

Page 89: ... also available use these to record inspection results Automatic Compression Release ACR This engine is equipped with an Automatic Compression Release ACR mechanism ACR lowers compression at cranking speeds to make starting easier Operation The ACR mechanism consists of a lever and control pin assembly attached to the gear on the camshaft At cranking speeds 700 RPM or lower the control pin protrud...

Page 90: ... While most commercially available cylinder hones can be used with either portable drills or drill presses the use of a low speed drill press is preferred as it facilitates more accurate alignment of the bore in relation to the crankshaft crossbore Honing is best accomplished at a drill speed of about 250 RPM and 60 strokes per minute After installing coarse stones in hone proceed as follows 1 Low...

Page 91: ...ton to bore clearance 1 With a micrometer measure the diameter of the piston perpendicular to the piston pin and up from the bottom of the piston skirt as indicated in Figure 10 2 based on the model involved 2 Use an inside micrometer telescoping gauge or bore gauge and measure the cylinder bore Take the measurement approximately 63 5 mm 2 5 in below the top of the bore and perpendicular to the pi...

Page 92: ...Diameter 89 37 987 38 013 mm 6 5 mm 7 033 7 058 mm 35 63 35 37 mm 45 1 5 mm 6 982 7 000 mm 89 34 013 33 987 mm 6 5 mm 7 033 7 058 mm 31 63 31 37 mm 45 1 5 mm 6 970 6 988 mm To check valve guide to valve stem clearance thoroughly clean the valve guide and using a split ball gauge measure the inside diameter Then using an outside micrometer measure the diameter of the valve stem at several points on...

Page 93: ...umption can also occur when the piston ring end gap is incorrect Oil control is also lost when ring gaps are not staggered during installation When cylinder temperatures get too high lacquer and varnish collect on pistons causing rings to stick which results in rapid wear A worn ring usually takes on a shiny or bright appearance Scratches on rings and pistons are caused by abrasive material such a...

Page 94: ...sed Some important points to remember when servicing piston rings 1 If the cylinder bore does not need reboring and if the old piston is within wear limits and free of score or scuff marks the old piston may be reused 2 Remove old rings and clean up grooves Never reuse old rings 3 Before installing the rings on the piston place the top two rings each in turn in its running area in the cylinder bor...

Page 95: ...g last Refer to Figure 10 8 Figure 10 8 Piston Ring Installation 1 Oil Control Ring Bottom Groove Install the expander and then the rails Make sure the ends of expander are not overlapped 2 Compression Ring Center Groove Install the center ring using a piston ring installation tool Make sure the pip mark is up and the PINK dykem stripe is to the left of end gap 3 Compression Ring Top Groove Instal...

Page 96: ...ve Piece Oil Pressure Relief Valve Hydraulic Lifters Inspection Check the base surface of the hydraulic lifters for wear or damage If the lifters need to be replaced apply a liberal coating of Kohler lubricant see Section 2 to the base of each new lifter before it is installed Bleeding the Lifters To prevent a possible bent push rod or broken rocker arm it is important to bleed any excess oil out ...

Page 97: ...l oil seal PTO and Flywheel End 12 Install stator and wiring harness 13 Install flywheel fan grass screen and drive cup 14 Install fuel line 15 Install ignition module 16 Assemble and install cylinder head 17 Install carburetor adapter and heat deflector 18 Install baffles and blower housing 19 Install valve cover and muffler bracket 20 Install fuel pump 21 Install electric starter 22 Install fuel...

Page 98: ...o Connecting Rod Install Piston and Connecting Rod NOTE Proper orientation of the piston connecting rod inside the engine is extremely important Improper orientation can cause extensive wear or damage 1 Stagger the piston rings in the grooves until the end gaps are 120 apart Figure 11 3 Installing Cross Shaft Install Crankshaft 1 Lubricate the flywheel end bearing surfaces of the crankshaft and cr...

Page 99: ...ypes of connecting rod bolts have been used in production and each has a different specific torque value See Figures 11 8 and 11 9 The 8 mm straight shank style rod bolts must be torqued in increments to 22 7 N m 200 in lb The 8 mm step down shank style rod bolts must be torqued in increments to 14 7 N m 130 in lb The 6 mm straight shank style rod bolts must be torqued in increments to 11 3 N m 10...

Page 100: ...kcase and balance shaft with engine oil 2 Align the timing mark on the balance shaft gear and the larger gear on the crankshaft Lower the balance shaft into the bearing surface in the crankcase 3 Make sure the balance shaft gear large crankshaft gear and the governor gear teeth mesh and the timing marks are aligned See Figure 11 10 Install Hydraulic Lifters and Camshaft 1 See Hydraulic Lifters in ...

Page 101: ...ay 6 Repeat steps 4 and 5 until the end play is within the specified range Install Oil Pressure Relief Valve Five Piece Oil Pressure Relief Valve 1 Place the relief valve body in the cavity of the closure plate 2 Insert the piston and spring into the body See Figure 11 14 Crankshaft Timing Mark Small Crankgear Camshaft Timing Mark 4 Align the timing marks the camshaft gear and the smaller gear on ...

Page 102: ...1 17 Do Not use Loctite Figure 11 17 Center Punch Stake Marks Center Punch Stake Marks O Ring Clip Oil Pickup Hex Flange Screw Figure 11 18 Installing Oil Pickup Components Install Closure Plate to Crankcase RTV silicone sealant is used as a gasket between the closure plate and crankcase Refer to page 2 3 for a listing of approved sealants that may be used NOTE Always use fresh sealant Using outda...

Page 103: ...oil pump rotors See Figure 11 21 Figure 11 20 Closure Plate Fastener Torque Sequence 1 2 3 4 5 6 7 8 9 10 11 12 Inner Rotor Balance Shaft Outer Rotor Figure 11 21 Installing Oil Pump Gears and O Ring 2 Install the O Ring in the groove in the closure plate 3 Install the oil pump cover machined side toward O Ring Secure with three hex flange screws See Figure 11 22 NOTE Apply sealant to the oil pump...

Page 104: ... the flywheel when tightening the flywheel fastener Do not use any type of bar wedge between the cooling fins or flywheel ring gear as these parts could become cracked or damaged 1 Install the fan spacers and hex flange screws to the flywheel See Figure 11 25 2 Torquethe hexflange screws to 9 9 N m 88 in lb Install Oil Seals PTO End and Flywheel End 1 Slide a seal protector sleeve over the cranksh...

Page 105: ...ses Install the ignition module to the bosses on the crankcase The directional arrow denoting proper flywheel rotation must be up Move the module as far from the flywheel magnet as possible Tighten the hex flange screws slightly 2 Insert a 25 mm 0 010 in flat feeler gauge or shim stock between the magnet and ignition module See Figure 11 28 Loosen the hex flange screws so the magnet pulls the modu...

Page 106: ...e kill lead to the tab terminal on the ignition module Reassemble Cylinder Head Components See Figure 11 29 thru 11 31 1 Rocker Bridge Heads Only Install the rocker bridge to the cylinder head Make sure the small counterbored hole is toward the exhaust port side of the cylinder head Secure the rocker bridge with two M6 hex cap screws Torque the screws to 9 9 N m 88 in lb 2 Install the intake valve...

Page 107: ...plate some models only Start the screws into the head and finger tighten only at this time See Figure 11 33 Rocker Shaft Rocker Arms Spark Plug Figure 11 34 Installing Cylinder Head 3 Install a new cylinder head gasket and the cylinder head assembly on the crankcase Slide the spacer and washer onto one of the new head bolts and install it in the 5 position between the intake and exhaust ports See ...

Page 108: ... Light leads if used See Figure 11 39 Heat Deflector Carburetor Adapter Blower Housing Indicator Light Leads 4 Rocker Bridge Heads Figure 11 36 Compress the valve spring and seat the push rods into sockets under the end of the rocker arms Figure 11 36 Installing Push Rods Under Rocker Arms Rocker Bridge Style Heads Head with Separate Pivots Rocker Arms Figure 11 37 Seat the push rods into sockets ...

Page 109: ...lants NOTE Always use fresh sealant Using outdated sealant can result in leakage Refer to Section 2 Tools Aids for information on the sealant dispenser 1 Prepare the sealing surfaces of the cylinder head and valve cover following Service Bulletin 252 If it is a stamped steel valve cover the flatness of the sealing surface must be checked prior to reinstallation See Section 10 2 Apply a 1 16 bead o...

Page 110: ... the outlet fitting of the fuel pump Secure the fuel line to the outlet fitting with the other hose clamp Install Electric Starter Electric Starter Inertia Drive or Solenoid Shift 1 Install the studs for starter into the crankcase if applicable and removed previously The longer set of threads must be out 2 Install starter with spacer and ground lead if used on the studs or install starter using th...

Page 111: ...e the screws to 7 3 N m 65 in lb See Figure 11 50 3 Torque the hex flange nuts to 24 4 N m 216 in lb See Figure 51 Figure 11 47 Installing Electric Starter 3 Install fuel tank solenoid bracket if equipped onto the mounting studs Secure with the two hex flange screws through the closure plate with the single spacer behind the bracket on the lower screw Torque the screws to 24 4 N m 216 in lb See Fi...

Page 112: ...or ground lead plastic blower housing models was also secured position it behind the throttle bracket on the lower screw See Figure 11 54 Figure 11 54 Installing Throttle Bracket Figure 11 52 Installing Rectifier Regulator Install Carburetor and External Governor Components 1 Install the rubber fuel line and two hose clamps to the metal fuel line Secure the rubber fuel line to the metal fuel line ...

Page 113: ... Base and Air Intake System Adjust Governor Lever 1 Connect choke linkage to the carburetor choke lever See Figure 11 56 2 Install a new air cleaner base gasket onto the mounting studs Figure 11 55 Installing Governor Spring RPM should be checked with a tachometer Figure 11 56 Connecting Choke Linkage Figure 11 57 Installing Air Cleaner Base 5 Adjust Governor Lever a Pull the governor lever away f...

Page 114: ...er 7 Install the air cleaner cover and knob See Figure 11 60 Figure 11 60 Installing Air Cleaner Cover Install Retractable Starter 1 Install the retractable starter and five hex flange screws to blower housing Leave the screws slightly loose 2 Pull the starter handle out until the pawls engage in the drive cup Hold the handle in this position and tighten the screws securely See Figure 11 61 Air Cl...

Page 115: ...over completely and compression is noted the lifters have bled down sufficiently and the engine can be test run If however it can not be turned over completely locks up at some point return the piston to TDC between the intake and exhaust strokes and wait ten minutes to allow the lifters time to bleed down then check for compression again If started with extended lifters bent push rods or other en...

Page 116: ...LITHO IN U S A FORMNO TP 2402 A ISSUED 6 90 REVISED 8 06 ENGINE DIVISION KOHLER CO KOHLER WISCONSIN 53044 FOR SALESAND SERVICE INFORMATION IN U S AND CANADA CALL 1 800 544 2444 ...