ENGINES Kohler

KOHLER TWO-CYCLETWO AND THREE CYLINDER MODELS

CONDENSED SERVICE DATAENGINE MODEL K295.2T K295-2AX K340-2T K34Q-2AX SK340-2AS K-340-2FA K399-2T K399-2AX

Bore-(mm) 57.5 57.5 62 62 60 62 65 65Inches 2.26 2.26 2.44 2.44 2.362 2.44 2.56 2.56

Stroke-(mm) 56 56 56 56 60 56 60 60Inches 2.2 2.2 2.2 2.2 2.362 2.2 2.36 2.36

No. of Cylinders 2 2 2 2 2 2 2 2Displacement-(cc) 292 292 338 338 339 338 398 398

Cubic Inches 17.8 17.8 20.6 20.6 20.7 20.6 24.3 24.3Horsepower@RPM . . . . .... 24@6500 24@5500 28@6500 .... .... 28@6000 32@6500Cooling Type Cent. Fan Axial Fan Cent. Fan Axial Fan Axial Fan Free Air Cent. Fan Axial FanCarburetor Model HR-WR HR-WR HR-WR HR-WR HR-WR VM or B HR-WR HR-WR

Number Used 1 1 1 1 l i i iIgnition:

Type ET ET ET ET CD CD ET ETPoint Gap-(mm) 0.4 0.4 0.4 0.4 .... .... 0.4 0.4

Inch 0.016 0.016 0.016 0.016 .... .... 0.016 0.016Timing Advance? Yes Yes Yes Yes Yes Yes Yes YesTimingBTDC(mm)... 2.3 2.3 2.3 2.3 .... 2.12 2.3 2.3Inch 0.090 0.090 0.090 0.090 .... 0.085 0.090 0.090DegreesMeasured at Adv. Adv. Adv. Adv. .... 6000 Adv. Adv

Spark Plug:Bosch W260T2 W260T2 W260T1 W260T2 .... .... M240T1 W260T2Champion N2 N2 L78 N2 N19V QN-3 K8 N2Electrode Gap-(mm) . 0.5 0.5 0.5 0.5 .... 0.635 0.5 0.5

Inch 0.020 0.020 0.020 0.020 .... 0.025 0.020 0.020Fuel/Oil Ratio 20:1 20:1 20:1 20:1 20:1 50:1 20:1 20:1

ENGINE MODEL K440-2T K440-2AX K44G-2SS K440-2AS K618.2 K645-3SS

Bore-(mm) 68 68 67.5 68 75 67.5Inches 2.68 2.68 2.66 2.677 2.95 2.66

Stroke-(mm) 60 60 60 60 70 60Inches 2.36 2.36 2.36 2.362 2.75 2.36

No. of Cylinders 2 2 2 2 2 SDisplacement-(cc) 436 436 430 436 618 644

Cubic Inches 26.7 26.7 26.0 26.7 37.7 39.2Horsepower @RPM 30@6000 37@6500 .... .... 33<^5000Cooling Type Cent. Fan Axial Fan Free Air Axial Fan Cent. Fan Free AirCarburetor Model HR-WR HR-WR HD-WD HD-WD HR HD-WD

Number Used 1 1 2 2 1 3Ignition:

Type ET ET ET CD ET ETPoint Gap-(mm) 0.4 0.4 0.4 ... 0.4 0.4

Inch 0.016 0.016 0.016 .... 0.016 0.016Timing Advance? Yes Yes Yes Yes Yes YesTiming BTDC (mm)... 2.3 2.3 2.3 .... 3.0 2.3

Inch 0.090 0.090 0.090 .... 0.118 0.090DegreesMeasured Adv. Adv. Adv. .... Adv. Adv.

Spark Plug:Bosch M240T1 W260T2 .... .... M225T1Champion K8 N2 .... N19V K7

Electrode Gap-(mm).. . 0.5 0.5 0.5 .... 0.5 0.5Inch 0.020 0.020 0.020 .... 0.020 0.020

Fuel/Oil Ratio 20:1 20:1 20:1 .... 20:1 20*1

337

Kohler ENGINES

Fig. I^To cure vapor lock on models IC3M-2 andK440'2, cut hole In end plate to dimensions

shown above as outlined In text

MAINTENANCE

CARBURETOR. Tillotson, Walbroor Mikuni carburetors are used. Refer toappropriate Carburetor Section forspecific overhaul information. An ex-ternal impulse line is used to operate thefuel pump. Be sure all passages are openand that vacuum and pressure leaks areeliminated.

NOTE: On modals K399-2 and K440-2 en-countering vapor lock, a 1V4 in. hole cut Inend plate adjacent to carburetors willallow air to be blown across carburetors.Cut hole using dimensions in Fig. 1. Ac-cess to end plate is possible by removingstarter and biower housing, or by remov-ing intake manifold assembly. Stuff ragsin intake ports if hoie is cut from carbure-tor side.

IGNITION AND TIMING. Onmodels equipped with breaker points,point gap should be 0.016 in. Both setsof points must be adjusted to open exact-ly 180"* apart. Engines are equippedwith a centrifugal timing advance whichprovides retarded timing for startingonly. Advance timing position is markedby a chipped fan blade and an aligjimentmark on fan housing. Hold flyweight inadvanced position as shown in Fig. 2,when checking ignition timing.

The Capacitor Discharge Ignition(CDI) system uses a permanent magnetflywheel to induce voltage into excitercoil. The exciter coil then sends currentto CDI unit where a diode allows onlyDC current to flow into a capacitor.When gate control switch in CDI unitreceives the small current signal fromthe pulser coil, it closes and allows thecapacitor to discharge its stored voltage

into the ignition coil. The coil then "stepsup" voltage enough to fire both sparkplugs simultaneously.

If an engine problem is experiencedcheck fuel system, electrical connec-tions, wiring and spark plugs. To testCDI ignition system a special tester orohmmeter must be used. DO NOT use a12 volt test light as it may damage theCDI system.

Timing is electronic and should notchange once properly adjusted. Checktiming with an electronic timing light. Iftiming has changed, check for a looseflywheel nut, sheared flywheel key, orloose mounting screws on stator baseplate. To check ignition timing, firstremove drive belt. Connect a timinglight to No. 1 spark plug wire and atachometer to No. 2 plug wire. Startengine and run at 6000 rpm. Aim timinglight at hole in flywheel housing andcheck to see if mark on flywheel lines upwith mark on flywheel housing. If tim-ing is incorrect, adjust timing statorplate and recheck timing marks for cor-rect alignment. Reinstall drive belt.

LUBRICATION. Engine is lubri-cated by mixing oil with the fuel. Therecommended ratio is 20:1 for all modelsexcept K-340-2FA. Use Regular orPremium gasoline and SAE 40 (Diluted)two-cycle (air-cooled) engine oil.

For Model K-340-2FA manufacturerrecommends a gasoline with an octanerating of 88 or higher, mixed with a two-cycle BIA certified oil or suitableequivalent at a ratio of 50:1.

Mix fuel and oil thoroughly using aseparate container before pouring mix-ture into fuel tank. For cold weatherblending, pre-mix the oil with a smallamount of gasoline and shake thor-oughly until mixture is liquid, then blendwith remainder of fuel. Do not use kero-sene or fuel oil for premixing.

COOLING FAN AND BELT. Thecooling fan drive belt should have ap-proximately %-inch deflection measuredmidway between pulleys as shown by ar-rows, Fig. 3. To adjust the belt, use a

Fig, 2—Breaker cam must ba hald in advancedposition when checking timing.

Fig, 3 - O n axlai fan modets, cooling fan drivebelt shouid kave approximately Vi-/ficft daflec*tion whan finger pressure is applied at pointshown by arrows, A pin-type spanner wrench (W)Is used to hold fan pullaf to remove shaft nut

suitable pin-type spanner (W) to hold theupper pulley and remove fan shaft nut.Transfer shims from between pulleyhalves to front of pulley to tighten beltor add shims to loosen belt. Tighten fanshaft nut to a torque of 35 ft.-lbs. Whena new belt is installed, tension should bechecked after the first 2 or 3 hours ofoperation.

REPAIRS

TIGHTENING TORQUES. Recom-mended tightening torques are as fol-lows: (All values are given in ft.-lbs.).

CENTRIFUGAL FAN MODELSBearing Plates

K618-2 16All Other Models 13

Crankcase and Cylinder NutsK618-2 32All Other Models 18

Crankcase Flange Bolts (K618-2) 17Cylinder Head Bolts

K295-2T 18K618-2 32Other Models 22

Flywheel 100Intake Manifold 13Spark Plug

K295-2T-K340-2T 14Other Models 18

NOTE: To determine type of threads us-ed on engine, refer to engine specificationnumber. If number has six digits, threadsare U.S. standard, if specification numberhas seven digits, refer to suffix of twonumbers. Numbers from 01 to 05 indicatemetric threads while numbers from 06 to20 indicate U.S. standard threads.

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ENGINES Kohler

AXIAL FAN MODELSCrankcase and Cylinder Nuts 16Crankcase Flange Bolts 13Cylinder Head 18Drain Plug 8Fan ShaftNut 40Flywheel 95Manifold Halves 8Spark Plug 14

MODEL K-340-2FACrankcase Halves 9Crankcase to Cylinder 18Cylinder Head 18Intake Manifold 18Exhaust Manifold 18Flywheel 90Sparkplug 20

DISASSEMBLY AND REASSEM-BLY. Repair sections are divided intothree types; axial fan twin, centrifugalfan twin and late K-340-2FA model.K-440-2SS and K-645-3SS models arelisted in CONDENSED SERVICEDATA Tables but specific overhaul datais not given. Repair procedures differ onengine models, refer to the appropriatefollowing paragraphs for suggested pro-cedures.

CENTRIFUGAL FAN MODELS.Refer to Figs. 4 and 5 for explodedviews of engine. If the Engine Specifi-cation number has seven digits and thelast two are 05 or lower, the engine hasmetric threads. All other engines haveU.S. Standard threads. As an example,metric threads will be found on K399-2and K618-2 engines.

To disassemble the removed engine,first remove carburetor, manifolds,drive clutch, starter, air shroud and fly-wheel. Cooling fins on early models were

12

1. Piston rings2. Piston3. Piston pin4. Needle bearing5. Bearing plate6. Oil seal7. Thrust washer8. Bearings9. Crankshaft assy.

10. Thrust washer11. Oil seal12. Starter cup

Fig. S-Explodod view of cnnkshaH, pistons and associated parts used on centrifugal fan engines.

cast square with heads as shown in up-per view, Fig. 6. Late models have obli-que fins as shown in lower view. Cyl-inder heads or shrouds are not inter-changeable between the two types. Onall models, carefully note or mark posi-tioning of heads so they can be installedin correct position.

When removing drive-end bearingplate (5-Fig. 5) note number of shims(7) on shaft. Keep shims with bea '̂ingplate for reassembly. Scratch-markmagneto plate to assist in timing duringreassembly, then remove magneto plate,flywheel end plate and shims (10). Notenumber of shims (10) and keep with endplate for reassembly.

Scratch-mark cylinders and crankcasefor identification and remove cylindersand pistons, keeping No. 1 and No. 2

Fig. 4-Exploded view ofmalor housing componentsused on centrifugal fan

models.

assemblies separate and identified.Remove the retaining stud nuts and,supporting upper crankcase half, bumpcrankshaft gently with a soft hammer tobreak the sealant and separate thehalves; then lift off upper crankshafthalf and lift out crankshaft.

When reassembling the engine, makesure all parts are clean. Insert crankcasethrough-bolts in lower crankcase halfand attach to a suitable engine stand,then lower crankshaft into position incrankcase half. Install both crankcaseend plates and removed shim packs on

Fig. 6-On early models, cooling air outlet waslocated on carburetor side of engine andcylinder head cooling fins run crosswise asshown In upper view. On later engines, coolingair outlet Is located at drive end of engine and

oblique cooilng fins are used (lower view).

339

Kohler ENGINES

Fig. 7 - 4 Chain Clamp Tool Is available from theengine manufacturer which can b« used for a

number of holding operations.

lower crankcase half and snug up retain-ing cap screws. Slide crankshaft solidlytoward fiywheel end of housing asshown in Fig. 8 and measure end clear-ance between crankshaft bearing anddrive end housing using a feeler gage asshown. Clearance should be 0.006-0.012;if it is not, vary the thickness of eithershim pack (7 or 10-Fig. 5) as required.Shims are available in thicknesses of0.006 and 0.012. Remove both bearingplates leaving shim pack in position oncrankshafts. Coat fiange areas of bothcrankcase halves evenly and lightly withKOHLER Crankcase Sealer (or equiva-lent). Lubricate all bearings with clean,light oil and reassemble crankcasehalves and end plates.

Heat the piston and install piston pin,with piston ring locating pins positionedon carburetor side of crankcase. Thelighter colored piston ring should be in-stalled in lower ring groove and thedarker (moly coated) ring in top groove.Make sure both rings are properly posi-tioned over locating pins, then install

Fig, 9-Exploded view of major housing components usad on axiai fan modais. Note split cylindershroud and two-piaca intaka manifoid. Minor diffarancas exist betwaan iarga and smaii anginas;

rafar aiso to Fig, It,

cylinders using new base gaskets and asuitable ring compresser. Install andtighten intake manifold to align the cyl-inders, then tighten all crankcasethrough-bolts. Complete the assemblyby reversing the disassembly procedure.

AXIAL FAN MODELS. Refer toFigs. 9, 10 and 11 for exploded views.All engines are equipped with U. S.Standard threads.

To disassemble the removed engine,first remove drive clutch, starter, air

12 13

Fig, 10-Explodad view of crankshaft, pistons and associated parts usad on big block axial fanmodals, Smail biock anginas are similar axcapt and platas (Fig, 11) control crankshaft and play

Instead of snap rings (6 A 12),

Fig. 9-Push crankshaH of partially assambiadengine to flywheel side and measure and play

with a feeler gage as shown.

1. Piston rings2. Piston3. Piston pin4. Needle bearing

5. Oil seal6. Snap ring7. Shim pack

8. Bearing9. Crankshaft assy.

10. Bearing

11. Shim pack12. Snap ring13. Oil seal

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ENGINES Kohler

Fig. I f - O n smali block engines, end platescontrol crankshaft end play Instead of snap

rings shown in Fig. 10.

shrouds and flywheel. Intake manifoldcarburetor side may be removed alongwith carburetor; removal is necessaryfor access to the two center manifoldstud nuts. Do not attempt to removethreaded exhaust tubes unless renewalis indicated. Tubes are installed with aspecial hardening sealer, and removal isdifficult and unnecessary for normal ser-vice.

Scratch-mark cylinder heads, cylin-ders and crankcase for identification,then remove cylinder heads, cylindersand pistons. Keep No. 1 and No. 2assemblies separate and identified.Scratch-mark armature plate to assist intiming at reassembly and remove ar-mature plate and fan housing. On modelK295-2AX and K340-2AX, removedrive-end bearing plate. Remove fiangebolts or stud nuts. Support uppercrankcase half and bump crankshaftgently with a soft-faced hammer tobreak the sealant grip, then separatecrankcase halves and remove crankshaftunit.

When reassembling the engine, makesure all parts are clean. Install crank-case through-bolts in lower crankcasehalf and attach crankcase half to a suit-able engine stand, then lower crankshaftin position. On large block engines, in-stall the removed shim packs (7 & 1 1 -Fig. 10) and fit snap rings (6 & 12) incrankcase bore grooves. On small blockmodels, install removed shim packs andend plates (Fig. 11). On all models, slidecrankshaft toward fiywheel end andmeasure crankshaft end clearance usinga feeler gage as shown in Fig. 8. Clear-ance should be 0.006-0.012; if it is not,vary the thickness of either shim pack (7or 11-Fig. 10). Shims are available inthicknesses of 0.006 and 0.012. On en-gines so equipped, remove end platesleaving shim packs in place; on othermodels, position oil seals (5 & 13-Fig.10) on shaft in lower crankcase half.Lubricate all bearings using light oil andcoat both crankcase mating fianges with

KOHLER Crankcase Sealer or equiva-lent. Reinstall crankcase upper half andon models so equipped, install bearingend plates.

Heat the piston and install piston pin,with piston ring locating pins positionedon carburetor side of crankcase. Asquare-section ring is used in lower ringgroove, an L-ring in upper groove. Makesure rings are properly positioned overlocating pins, then install cylinders usingnew base gaskets and a suitable ringcompresser. Install and tighten intakemanifold base half to align the cylinders,then tighten all crankcase through-bolts.Complete the assembly by reversing thedisassembly procedure.

MODEL K-340-2FA. Refer to Fig.11A and IIB for exploded views ofengine assembly.

To disassemble the removed engine,first remove drive clutch, engine base,intake and exhaust manifolds, sparkplugs and recoil starter. Remove fiy-wheel retaining nut and locking platie,then using a suitable puller withdrawfiywheel from crankshaft. Remove fiy-wheel housing with CDI unit and coil at-tached to housing, then remove statorassembly. Remove cylinder heads andcylinders. Remove piston pin retainingrings, then push piston pins out andremove pistons. Remove crankcase re-taining cap screws and split case in half.Lift crankshaft assembly out of housing.

Inspect crankcase halves for pitting,scoring or any other damage. Inspectcylinder heads and cylinders for exces-sive distortion. Cylinder head or cylin-

10 11 12 13

Fig, 11B-Exploded view of crankshaft assembly and associated parts for Modei K-340-2FA.

Fig. 11 A —Exploded view of crankcase and cy-linder assembly for model K-340'2FA.

1.2.3.4.

Piston ringPistonPiston pin and circlipNeedle bearing

5. Oil seal6. Snap ring7. Shim pack and

"Oaring

8.9.

10.

Roller bearingCrankshaft ass<Roller bearing

embly11.12.13.

Shim packS n ^ ringOil seal

341

Kohler ENGINES

Fig. 12--Various locations of piston ring posi-tioning pin hawa bean usad as shown. L-rlng (up-par right) is usad in top groota on K29S-2T and

aii axial fan modais.

der should be renewed if distortion ismore than 0.002-inch. Measure cylinderbore for out-of-roundness or excessivetaper. Accepted allowable wear toler-ance is 0.002-inch. Cylinder assemblymust be renewed if beyond specification.Cylinder bore is chrome-plated and can-not be honed or rebored. Check pistonsfor pitting, scoring, corrosion or anyother damage. Measure piston pin bore.

Fig. 13—Support crankshaft bahind countar-waights whan prassing l>aarings.

pin diameter and piston skirt diameter.Specifications are as follows: pistonskirt, 2.4364-2.4370 inches; piston pindiameter, 0.6297-0.6301 inch; piston pinbore, 0.6298-0.6302 inch. Inspect crank-shaft for excessive wear, damped rollerbearings or any other damage. Connect-ing rod̂ side clearance should be 0.006-0.016 inch. Crankshaft runout shouldnot be more than 0.002-inch. Renew allparts as needed. Crankshaft outer bear-ings may be renewed using a suitablepuller and installation tool.

During reassembly all "0" rings,gaskets and seals should be renewed.Correct crankshaft end play is0.006-0.012 inch. Add or remove shimsfrom between end bearings and retain-ing rings until correct distance is ob-tained.

Reassemble engine in reverse order ofdisassembly. Listed below are someitems to follow during reassembly:

1. Install piston on connecting rodswith arrows pointing toward ex-haust side.

2. Piston ring end gap measured one-inch down from top of cylindershould be aOlO-0.015 inch. If nec-essary, file ring end until correctmeasured gap is obtained.

3. Install new cylinder-to-crankcasegaskets with tabs toward exhaustport side.

4. During installation of cylinder as-semblies, install intake manifold tocylinders before tightening cylin-der retaining nuts as to insurealignment of cylinders.

Refer to TIGHTENING TORQUEsection for torque specifications. Tight-en cylinder head retaining nuts in acriss-cross sequence.

PISTONS, RINGS AND CYLIN-DERS. Engine Models K-440-2SS andK-645-3SS are listed in CONDENSEDSERVICE DATA Tables but specificrepair data is not given. For ModelK-340-2FA refer to DISASSEMBLYAND REASSEMBLY section for repairprocedures. For all other engine modelsrefer to the following paragraphs forservice data.

On some engines, cylinder head can beinstalled in more than one position andshould be marked before removal.Renew any head with broken or missingfins, damaged spark plug threads orother damage.

Maximum cylinder taper or out-of-round is 0.006. Cylinders can be honedor rebored, and pistons and rings areavailable in oversizes of 0.010, 0.020 and0.040.

Piston ring locating pins may be in-stalled at top, bottom or center of ringgroove as shown in Fig. 12, and the cor-

Fig, 14 - Waar of connecting rod big-end t^earlngand crankpin can ba checked by determining theaxial "rock" or "Sida Shaka' of rod at smali andas shown at (A), Waar may be considered axcas-

sifa if sida shaka exceeds 0,080 in. (2,0 mm).

rect ring must be installed. On axial fanengines and K295-2T an L-ring is usedin top ring groove. Other engines used adark colored (moly coated) top ring.Recommended piston ring end is0.012-0.018 for model K618-2,0.008-0.014 for K295-2T and all axial fanmodels; and 0.()10-0.016 for all othermodels. Piston ring side clearance usingnew rings should not exceed 0.005 fortop ring or 0.004 for bottom ring onmodel K618-2, 0.003 for bottom ring onmodels K295-2T or axial fan engines; or0.004 for any other ring on any model.

CRANKSHAFT ASSEMBLY. En-gine Models K-440-2SS and K-645-3SSare listed in CONDENSED SERVICEDATA Tables but specific repair data isnot given. For Model K-340-2FA referto DISASSEMBLY AND REASSEM-BLY section for repair procedures. Forall other engine models refer to thefollowing paragraphs for service data.

The crankshaft and connecting rodsare available only as a complete unit andshould not be disassembled.

Bearings are a press fit on crankshaftand will not normally need to be re-moved unless renewal is indicated. Ifbearings must be removed, support thecrankshaft below the counterweights asshown in Fig. 13 when reinstalling bear-ings.

Check for wear of the connecting rodbig end bearing by measuring the play atconnecting rod small end as shown inFig. 14. If side shake (A) exceeds 0.080inch (2.0 mm), unit is excessively worn

342

ENGINES

and crankshaft assembly should be re-newed. Also check for damage or rough-ness of crankshaft bearing by turningthe rod around crankpin.

Check for runout before installationby mounting the shaft between lathecenters as shown in Fig. 15. Runoutshould not exceed 0.0015. If runout isexcessive and remainder of unit isreusable, the unit may be straightenedby a machine shop or engine rebuilderexperienced with this type of construc-tion. If bearings, shafts or connectingrods are unserviceable, renew the crank-shaft unit.

Kohler

Fig. 15-Crankshaft runout should be checkedbefore instailation by mounting the unit in lathecenters as shown and measuring runout with

a dial indicator.

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