FOREWORD Goodoperation anda plannedmaintenance programas outlined in this manualare vital in obtainingmaximum engineperformance andlong enginelife. Theinstructions on the following pageshavebeenwritten with this in mind,to give the operatora better understanding of the various problemswhichmayarise, andthe mannerin whichthese problemscanbest be solved or avoided. The operator is cautioned against the use of any pans, other than genuineWisconsin parts, for replacementor repair.
IMPORTANT READTHESE INSTRUCTIONSCAREFULLY All pointsof operationandmaintenance havebeencoveredas carefully as possible,but if further informationis required,sendinquiries to the factory for promptattention. Whenwriting to the factory, ALWAYS GIVE THE MODEL,SPECIFICATION ANDSERIAL NUMBER of the engine referred to. Startin_o andODeratin_oNewEngines Carefulbreaking-inof a newenginewill greatlyincreaseits life andresult in troublefreeoperation.
IMPORTANT SAFETY NOTICE Properrepair is importantto the safe andreliable operationof an engine.This RepairManual outlines basic recommended procedures,someof whichrequire special tools, devicesor work methods. Improperrepair procedurescan be dangerous andcould result in injury or death.
SAFETY PRECAUTIONS ¯ Neverfill fuel tankwhileengineis runningor hot; avoidthepossibilityof spilledfuel causing a fire. Donot operateenginein a closedbuilding unless the exhaustis pipedoutside.Thisexhaustcontains carbonmonoxide,a poisonous,odorlessand invisible gas,whichif breathedcauses serious illness andpossibledeath. ¯ Always refuel slowlyto avoidspillage. ¯ When starting engine,maintaina safe distance from movingparts of equipment.
EXHAUST MUFFLER P RE-CLEANER AIR CLEANER CARBURETOR FUEL PUMP OIL FILLER AND BREATHER CAP FUEL PUMP PRIMER HANDLE AIR VENT HOLE GASOLINE STRAINER FUEL TANK CAP-----~ OIL SABER ~AGNETOSTOP SWITCH MAGNETO OIL FILTER TAKE.
NOTE: CYLINDERS, RINGS, PISTONS, PINS, TAPPETS, VALVES, CAMSHAFT, BEARINGS AND ETC. ARE LUBRICATED BY THE OIL SPRAY OR MIST THROWN OFF THE CONNECTING RODS AND CRANKSHAFT.
GENERAL INFORMATION and DESIGN HORSEPOWER R.P.M. 1400 17.2 Wisconsinengines are of the four cycle type, in which each of the four operations of intake, compression, expansion andexhaustrequires a complete stroke. This gives one power stroke per cylinder for each two revolutions of the crankshaft. 1600 1800 20.0 22.5 2000 2200 24.7 26.5 COOLING 2400 28.0 29.2 30.
GRADE OF OIL SEASONOR TEMPERATURE GRADEOF OIL Spring, Summer or Fall + 120°F to + 40°F Winter + 40°F to + 15°F + 15°F to 0°F BelowZero Use Oils classified SAE30 SAE 20-20W SAE 10w SAE 5W-20 as Service SE, SF, SGor CC Newengine 4 Qts. Crankcase Oil andfilter change 4 Qts. Capacity Less- filter or filter change 3~ Qts. off the engine and check the oil level by means of dip stick (oil gauge saber). If necessary, add enough oil to bring level up to the full mark.
IGNITION SWITCH Magnetoignition is standard on these engines, with a lever typeswitch onthesideofthemagneto, which isalways inthe onorrunning position, except whendepressed forstopping theengine. SeetopviewofFig.]. Onpower unit engines, a push button ignition switch is mountedon the outside of the housepanel at the flywheelend. See bottomview of Fig. 1. Whenstarting engine, the ignition switch button is pulled out. To stop, pushin. This will apply to both magneto and batteryignition systems.
Fig. 8 Fig. 7 is in good condition; otherwise use a new gasket. See Fig. 7, which shows the strainer mounted to the fuel tank of a power unit. On open engines, the strainer is mounted to the inlet of the fuel pump. MEASURE BREAKER POINT GAP WHEN~ OPEN. ADJUST TO .015 INCH CARBURETOR ADJUSTMENT BREAKER ARM- The main metering jet in the carburetor is of the fixed type, that is, it requires no adjustment.
Next, remove the spark plug from No. 1 cylinder and slowly turn the flywheel clockwise, at the same time holding a finger over the spark plug hole, so that the compression stroke can be determined from the air blowing out of the hole. The flywheel is marked with the letters ’DC’ near one of the air circulating vanes. This vane is further identified by an ’X’ mark ~cast on the end.See Fig. 11. When the air blows out o,f the No.
VERTICAL CENTERLINE MARK ON SHROUD FOR TIMING MAGNETO. No. 1 TERMINAL INDICATED ON MAGNETO END CAP AS SHOWN. OTHER TERMINALS FOLLOW FIRING ORDER IN CLOCKWISE ROTATION. EDGE OF VANE IN LINE WITH MARK ON SHROUD WHEN TIMING MAGNETO. ’X’ MARKED VANE ON FLYWHEEL NO 9-- NO NO 3 ~ 4 1 CRANKPtN 0 CRANKSHAFT GEAR RUNNING SPARK ADVANCE FOR CHECKING WITH NEON LIGHT. ~N~_3 CR~,NKPIM ~MARKED GEAR TOOTH, ~THUS ~ THROUGH OPENING, FLYWHEEL IS LOCATED DICATED ABOVE.
NEON LAMP TIMING SETGAP The engine should be timed to the 23° advanced position at not less than 2000 R.P.M. The timing should be checked with a neon lamp connected in series with No.1 spark plug. Chalkor paint the end of the "X" marked vane on Ihe flywheel, white. Then with the engine operating at 2000 R.P.M. or over, allow the flash from the neon lamp to illuminate the whitened vane.
maintaining satisfactory gines. They are: operation of gasoline en- 1. A proper fuel mixture in the cylinder. 2. 6ood compression in the cylinder. 3. 6ood spark, properly timed, to ignite the mixture. If all three of these conditions do not exist, the engine cannot be started. There are other factors which will contribute to hard starting; such as, too heavy a load for the engine to turn over at a low starting speed, a long exhaust pipe with high back pressure, etc.
To test for clogged fuel line, loosen fuel line nut at carburetor slightly. If line is open, fuel should drip out at loosened nut. Weak spark. See ’Magneto Ignition Spark’, or ’Distributor-Battery Ignition’, Page 12. COMPRESSION Magneto or distributor Loose connections at ignition cable. breaker points pitted Poor compression. See ’Compression’, Page 17. ENGINE SURGES OR GALLOPS Carburetor flooding. Governor spring hooked into wrong hole in lever. See ’Governor Ad/ustment’, Page 24.
possible, totaling applied. Loose or burnt out connecting rod bearing. Engine overheated heading. due to causes under previous ACCESSORIES Worn or loose piston pin. ENGINE BACKFIRES The air cleaner, oil filter, magneto, and if an electric starter and generator are used, these should be removed first. THROUGH CARBURETOR Water or dirt in gasoline. Remove clutch or clutch reduction unit if engine is equipped with either of these accessories. Engine cold. Poor grade of gasoline. Sticky inlet valves.
CYLINDER HEAD The cylinder head must be removed if it is necessary to regrind valves, or to work on the piston, rings or connecting rods. All of the cylinder head screws are plainly in view and can be easily removed. Screws of different lengths are used but these can be properly reassembled according to the various lengths of cylinder head bosses. In reassembly; remove all carbon and lead deposits from combustion chamber.
OIL PUMP(Fig. In reassembly; inspect crankshaft oil seal and replace if necessary. Be sure that oil sling is in place on crankshaft, then mount gear cover using a new flange gasket. Tap the two dowel pins in place and mount capscrews. Tighten screws 14 to 18 ft. Ibs. torque. Remove locknut and driver gear from shaft. If gear is too tight to remove by hand, use a puller, hammering on end of shaft to loosen gear will damage pump. Take out slotted pipe plug from bottom of crankcase.
STAMPED NUMBERS LOCATING LUGS SHELL BEARING Fig. 26 Fig. 28 MARK ON CAP OIL SPRAY NOZZLES Fig. 29 Fig, 27 are 90° from the axis of the piston pin hole, with the wide section of the piston skirt toward the maximum thrust side, or opposite the crankshaft rotation, See Engine Sectional, Fig. 2. crankshaft untilpiston is at top, then push connecting rod and piston assembly upward and out thru top of cylinder. Be careful not to mar the crank pin by allowing the rod bolts to strike or scrape across it.
PISTONTO CYLINDER AT PISTONSKIRT THRUSTFACE .003 to .004" PISTONRING GAP .010 to .020" TOP RING PISTONRING SIDE CLEARANCE IN GROOVES .002 to .004" SCRAPER RING OIL RING PISTONPIN TO CONNECTING RODBUSHING .002 to .004" .001 to .003" = .0004 to .0012 .0000to .0008" tight PISTONPIN TO PISTON CONNECTING RODTO CRANKPIN- SIDE CLEARANCE PLACEOPENENDOF RING ON PISTON FIRST AS SHOWN CONNECTING RODSHELLBEARING TO CRANKPIN DIA. (VERTICAL) Fig.
the tapered roller main bearings on the crankshaft. This end play should be .002 to .004 inch when engine is cold. There is practically no wear in these bearings so that no readjustment is necessary after proper assembly. VALVELIFTER When reassembling crankshaft, the timing marks on the crankshaft gear and the camshaft gear must be matched as shown in Fig. 24, otherwise engine will not operate properly, or if timing is off considerably, engine will not run at all.
ADJUSTMEN1 LOCKSCREW OIL FILLER AND INSPECTION PLATE ADJUSTMENT LOCK OIL LEVEL PLUG ADJUSTING RII (TURN IN CLOC~ WISE DIRECTION OIL DRAIN PLUG CLUTCH ENGAGING LEVER (RELEASED POSITION: Fig. 38 CLUTCH ADJUSTIvlENT Fig. 39 If the clutch begins to slip, it should be readjusted, otherwise it will become overheated and damaged. First remove the inspection plate which will expose the notched adjusting ring. Release the clutch, by pushing the engaging lever forward.
On engines where the pipe tap opening on the intake manifold is inaccessible, the rust preventative may be injected into the air intake on the carburetor while the engine is running, so the mixture will be drawn into the engine. The air cleaner connection will of course have to be disconnected from the carburetor to do this. OIL FILLER All the oil should be drained from the crankcase while the engine is warm, as the oil will then flow more freely than when cold.
FUEL PUMPSERVICE INSTRUCTIONS WISCONSINFUEL PUMPS, No. LP-38E, LP-38H and LP-38F (Cold Weather: -65°F) For all 4 cylinder engine models The fuel pump, like all other parts of the engine, is subject to wear and you will find that any time after 500 hours of use, its efficiency will gradually decrease. This is indicated by the engines faltering at high speeds or when heavy loads are suddenly applied. The pump can easily be restored to its normal efficiency by the installation of a repair kit.
When assured that the problem is with the alternator, follow the tests outlined in ’Trouble Shooting’. WIRING CIRCUIT, Flg. 42, Flg. 43 The fool-proof type connectors used to prevent incorrect wiring from the stator to the rectifier and regulator modules. To disconnect plugs, squeeze outer ends of receptical and pull apart. The rectifier is insulated from ground, but the stator and regulator module are grounded to the engine through their mounting surface.
Problem: Low/No Charge Test 2.0 Proceed with Test 1.0 and 1.1. It is necessary to slightly discharge battery t o make system work. 2.1 With engine running at full I~P~.~,, check bat tery voltage with DC Voltmeter. 2.2 If the charge rate increases -2.3 If system does not charge 2.4 If charge rate increased with regulator disconnected. 2.5 If the charge rate does not increase with regulator disconnected. Problem: Low/No Charge Test 3.
Test 7.0 STATOR GROUND Test Like the Regulator, the YB 81 and YB 82 Stators must be grounded. Stator ground can be checked with any type continuity device. TEST TESTER NO. RED LEAD I 2 Test TESTER BLACK LEAD RESULT To Ground DF 83- Light On DF81-Light On VOM-Continuity To Stator Black Lead To Other Black Lead 7.1 To Ground STATOR CONTINUITY I To Ground 2 To Ground 3 STATOR RUNNING VOLTAGE With the engine stopped, unplug all connectors between modules and stator.
L-57, L.77 Seri s CARBURETOR ZENITH MODEL87A8 SERVICE INSTRUCTIONS DESCRIPTION The Zenith87-Seriesis a horizontal carburetor with a con~ carburetor,because centricfuel bowl It is a ~balanced all air for fuel chamberand meteringwell ventilation and idling must come through the air cleaner. Air cleaner restrictions have a minimuminfluenceon the fuel-airratio ~. when a carburetoris thus =balanced The main jet and dischargejet are centrallylocated.
Adjust the the engine clockwise) to make it idle adjusting needle to obtain smooth idling of at idling speed. Turn the needle out (counterto make the mixture richer, and in (clockwise) leaner. CHOKEPLATE (CLOSEDPOSITION) INSPECTION OF PARTS 1. Float Assembly -- Replace if loaded with gasoline, damaged or if float axle bearing is worn excessively. Inspect float lever for wear at point of contact with fuel valve needle. Replace if wear is excessive. VENTURI 2.
L-63Serles CARBURETOR WISCONSIN L-63 SERIES ZENITH MODEL68-7 needlein this passagecontrolsthe suctionon the idle jet and therebythe idle mixture.Turningthe needlein closerto its seat results in a greater suction with a smaller amount of air and thereforea richermixture.Turningthe needleout away from its seat increasesthe amountof air and reducesthe suction,and a leanermixtureis delivered.
when startin{~ the engine. The choke valve is of a =semi=automatic s type, having a poppet valve incorporated in its design, which is controlled by a spring. The poppet valve opens automatically when the engine starts and admits air to avoid over-choking or flooding of the engine. The mixture required for starting is considerably richer than that needed to develop power at normal temperatures. As the engine fires and speed and suction are increased, the mixture ratio must be rapidly reduced.
DISASSEI~BLY ADJUSTMENTS,Fig. 1 Turn Idle speed screw (5), Fig. 3,in until throttle valve slightly opera With engine warmed up and running, turn adjusting screw in or out as required to obtain desired low idle speed (1000 to 1200 r.p.m.). Before disassembling: Clean outside of carburetorfrom all reignmaterial. When cleaninga completelyassembledcarburetor do not blow with compressed air, you may collapse the float. The Idle adjusting needle (14) should be seated lightly (clockwise), then backed out ] .
MAGNETOSERVICE INSTRUCTIONS FAIRBANKS-MORSE TYPE FM-X4B7A Y-97-$2 (With GD-93C-4 DRIVE GEAR) FORMODEL VH4D Wisconsin No. GENERAL DESCRIPTION Coil and condenser replacement while simple are not re©ommended unless adequate test equipment is available. N0 $*ttempt should be made to remove magnetic rotor from housing unless specific instructions for releasing the shaft are available.
SERVICE PARTSLIST PER-LUXYF50S1/YF50AS1 DISTRIBUTOR DISTRIBUTOR APPLICATION YF50SI and YF5OCSI YF50ASI and YF50DSI VH4D, SIDEMOUNT VH4D, TOP MOUNT ITEM NO. PART NO. DESCRIPTION -- 20121003 20121016 i -- 2 ........ 20121006 20121020 ........ QTY.
