Wisconsin VH4D Operating instructions

FOREWORD
Goodoperationanda plannedmaintenanceprogramasoutlined in this manualare vital in
obtainingmaximumengineperformanceandlongenginelife. Theinstructions onthe following
pageshavebeenwritten with this in mind,to give the operatora better understandingof the
variousproblemswhichmayarise, andthe mannerin whichtheseproblemscanbestbesolved
or avoided.
Theoperator is cautionedagainst the useof anypans, other than genuineWisconsin
parts, for replacementor repair. Thesepanshavebeenengineeredandtested for their
particular job, andthe useof anyotherpansmayresult in unsatisfactoryperformanceand
short enginelife. Wisconsindistributors anddealers, becauseof their close factory
relations, canrenderthe bestandmostefficient service.
THELIFE OF YOURENGINEDEPENDSONTHECAREIT RECEIVES.
The MODEL,SPECIFICATIONand SERIALNUMBERof your engine must be given when
ordering pans. TheMODELandSPECIFICATIONnumberare on the nameplate. TheSERIAL
NUMBERis stampedeither onthe crankcaseor the engine’sidentification tag.
Copythe MODEL,SPECIFICATIONand SERIALNUMBERin the spaces provided below so
that it will beavailablewhenorderingpans.
MODEL SPECIFICATION
SERIAL NUMBER
Toinsurepromptandaccurateservice, the followinginformationmustalso begiven:
1. State EXACTLYthe quantity of eachpanandpannumber.
2. Statedefinitely whetherpansareto beshippedbyexpress,freight or parcelpost.
3. Statethe exactmailingaddress.

IMPORTANT
READTHESEINSTRUCTIONSCAREFULLY
All pointsof operationandmaintenancehavebeencoveredascarefullyaspossible,but if further
informationis required,sendinquiriesto thefactoryfor promptattention.
Whenwriting to the factory, ALWAYSGIVETHEMODEL,SPECIFICATIONANDSERIAL
NUMBERof the enginereferred to.
Startin_oandODeratin_oNewEngines
Carefulbreaking-inof a newenginewill greatlyincreaseits life andresultin troublefreeoperation.
Afactorytest is notsufficient to establishthepolishedbearingsurfaces,whicharesonecessary
to the properperformanceandlonglife of anengine.Thesecanonlybeobtainedbyrunninga
newenginecarefully andunderreducedloadsfor a short time.
¯ Besuretheengineis filled to theproperlevelwitha goodqualityengineoil.
¯ Forproperproceduresto follow whenbreaking-ina newengine,see’TestingRebuiltEngine’.
Thevariousbearingsurfacesin a newenginehavenot beenglazed,astheywill bewith continued
operation,andit is in this periodof "runningin" that specialcaremustbeexercised,otherwise
the highly desiredglaze will neverbeobtained.Anewbearingsurfacethat hasoncebeen
damagedbycarelessnesswill beruinedforever.

IMPORTANT SAFETY NOTICE
Properrepair is importantto the safeandreliable operationof anengine.ThisRepairManual
outlines basicrecommendedprocedures,someof whichrequirespecialtools, devicesor work
methods.
Improperrepair procedurescanbedangerousandcouldresult in injury or death.
READANDUNDERSTANDALL SAFETYPRECAUTIONSAND
WARNINGSBEFOREPERFORMINGREPAIRSON THIS ENGINE
Warninglabels havealsobeenput onthe enginesto provideinstructionsandidentify specific
hazardswhich,if not heeded,couldcausebodilyinjury or deathto youor otherpersons.These
labels identify hazardswhichmaynot beapparentto a trained mechanic.Thereare many
potential hazardsfor anuntrainedmechanicandthereis nowayto label the engineagainstall
suchhazards.Thesewarningsin the RepairManualandonthe engineare indentified bythis
symbol:
z WARNING
Operationsthat mayresult onlyin enginedamageare identified in the RepairManualbythis
symbol: CAUTION
WisconsinMotors,LLCcannotanticipate everypossiblecircumstancethat mightinvolve
apotentialhazard;therefore,thewarningsin this manualarenotall inclusive.If a procedure,
tool, deviceor workmethodnot specifically recommendedby Wisconsinis used,youmust
satisfy yourselfthat it is safefor youandothers.Youshouldalso ensurethat the engine
will not be damagedor madeunsafeby the proceduresyouchoose.
IMPORTANT:Theinformation, specifications andillustrations in this manualare based
oninformation that wasavailable at the time it waspublished. Thespecifications,
torques, pressuresof operation, measurements,adjustments,illustrations andother
items can changeat any time. Thesechangescan affect the service given to the
product. Getthe completeandmostcurrent information before starting any job. For
parts, service, or information, contract WisconsinMotors,LLC,Memphis,Tennessee.

SAFETY PRECAUTIONS
¯Neverfill fuel tankwhileengineis runningorhot;
avoidthepossibilityof spilledfuelcausingafire.
¯ Alwaysrefuelslowlyto avoidspillage.
¯Whenstarting engine,maintaina safedistance
frommovingparts of equipment.
¯ Donot start enginewith clutch engaged.
Donot spinhandcrankwhenstarting. Keep
crankingcomponentscleanandfreefromconditions
whichmightcausethe crankjawto bindandnot
releaseproperly.Oilperiodicallyto preventrust.
¯Neverrunenginewith governordisconnected,or
operateat speedsin excessof 2800R.P.M.load.
Donotoperateenginein aclosedbuildingunless
theexhaustis pipedoutside.Thisexhaustcontains
carbonmonoxide,a poisonous,odorlessand
invisible gas,whichif breathedcausesserious
illness andpossibledeath.
Nevermakeadjustmentsonmachinerywhile it is
connectedto theengine,withoutfirst removingthe
ignition cablefromthesparkplug.Turningthe
machineryoverbyhandduringadjustingor
cleaningmightstart theengineandmachinerywith
it, causingseriousinjuryto theoperator.
¯Precautionis thebestinsuranceagainst
accidents.
Keepthis bookhandyatall times,
fanzilia~izeyourselfwiththeoperatingi~.¢~ctio~s.
Model VH4D
3-1/4" Bore m3-1/4" Stroke
107.7 cu. in. Displacement
2

EXHAUST MUFFLER
P RE-CLEANER
AIR CLEANER CARBURETOR
FUEL PUMP
FUEL PUMP PRIMER HANDLE
AIR VENT HOLE
FUEL TANK CAP-----~
OIL FILLER AND
BREATHER CAP
GASOLINE STRAINER
OIL SABER
~AGNETOSTOP SWITCH
MAGNETO
OIL FILTER
TAKE.OFF (Side Mount Tank) VIEW OF ENGINE
AIR VENT HOLE
FUEL TANK CAP ~ MUFFLER
FUEL TANK
OIL FILLER AND BREATHER
CYLINDER NUMBERS
AIR CLEANER
CHOKE BUTTON
VARIABLE SPEED
GOVERNORCONTROL
IGNITION SWITCH
FLYWHEEL SHROUD
OIL FILTER E TO
OIL DRAIN PLUG
POWER UNIT FAN END VIEW OF ENGINE
F~g.1
MODEl VH4D OPEN ENGINE AND POWER UNIT

NOTE:
CYLINDERS, RINGS, PISTONS, PINS, TAPPETS, VALVES,
CAMSHAFT, BEARINGS AND ETC. ARE LUBRICATED BY
THE OIL SPRAY OR MIST THROWNOFF THE CONNECT-
ING RODS AND CRANKSHAFT.
OIL SPRAY NOZZLES
OIL STRAINER
STANDARD LOCATION
OF OIL GAUGE SABER
OIL FILLER AND
BREATHER CAP
CRANKSHAFT OIL SLINGER
OIL PRESSURE RELIEF VALVE
SET FOR 15 POUNDS PRESSURE
OIL HEADER TUBE
OPTIONAL LOCATION
OF OIL GAUGE SABER
FULL AND LOW MARKS
ON OIL GAUGE SABER
OIL PUMP
STRAINER SCREEN
OIL FILTER
OIL LINE TO
GOVERNOR
OIL DRAIN PLUG
OIL RETURN FROM
FILTER INTO CRANKCASE
WITH ENGINE AT OPERATING TEMPERATURE, OIL PRESSURE
IN HEADER WILL BE APPROXIMATELY 5 POUNDS. AN OIL
PRESSURE GAUGE IS NOT REQUIRED.

GENERAL INFORMATION and DESIGN
Wisconsinengines are of the four cycletype, 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.
COOLING
Cooling is accomplished by a flow of air, circulated
over the cylinders and heads of the engine, by a
combination fan-flywheel encased in a sheet metal
shroud. The air is divided and directed by ducts and
baffle plates to insure uniform cooling of all parts.
Never operate an engine with any part of the
shroudingremoved.- this will retard air cooling.
Keepthe cylinder and head fins free from dirt and
chaff. Improper circulation of cooling air will
causeengine to overheat.
CARBURETOR
The proper combusUble mixture of gasoline and air
is furnished by a balanced carburetor, giving correct
fuel to air ratios for all speeds and loads.
IGNITION SYSTEM
The spark for ignition of the fuel mixture is furnished
by a high tension magneto driven off the timing gears
at crankshaft speed..The magneto distributor rotor
turns at half-engine speed. The magneto is fitted with
an impulse coupling, which makes possible a power-
ful spark for easy starting. Also, the impulse coupling
automatically retards the spark for starting, thus elim-
inating possible kick back from engine while cranking.
Battery ignition (12 volt); distributor is furnished
place of magneto on engines equipped with flywheel
alternator or belt driven generator. See Pages 12-15.
LUBRICATION SYSTEM(Fig. 3)
A gear type pump supplies oil to four nozzles which
direct oil streams against fins on the connecting rod
caps. Part of the oil enters the rod bearing through
holes in the rods, and the balance of the oil forms a
spray or mist which lubricates the cylinder walls and
other internal parts of the engine. An external oil line
from the oil header tube in the crankcase lubricates
the governor and gear train.
GOVERNOR
Agovernor of the centrifugal flyweight type maintains
the engine speed by varying the throttle opening to
suit the load imposed upon the engine. These engines
are equipped with either a fixed speed governor, a
variable speedcontrol to regulate the governed speed
of the engine, or an idle control.
ROTATION
The rotation of the crankshaft is clockwise when
viewing the flywheel or cranking end of the engine.
This gives counter-clockwise rotation when viewing
R.P.M.
1400
1600
1800
HORSEPOWER
17.2
20.0
22.5
2000 24.7
2200 26.5
2400 28.0
2600
2800 29.2
30.0
the power take-off end of the crankshaft. The flywheel
end of the engine is designated the front end, and the
power take-off end, the rear end of the engine.
HORSEPOWER
Horsepower specified in the accompanying chart is for
an atmospheric temperature of 60° Fahrenheit at sea
level and at a Barometric pressure of 29.92 inches of
mercury.
For each inch lower the Barometric pressure drops,
there will be a loss in horsepower of 31/~%.
For each 10° temperature rise there will be a reduc-
tion in horsepower of 1%.
For each 1000 ft. altitude above sea level there will
be a reduction in horsepower of 3~/2%.
The friction in new engines cannot be reduced to the
ultimate minimum during the regular block test, but
engines are guaranteed to develop at least 85 per cent
of maximumpower when shipped from the factory. The
power will increase as friction is reduced during the
first few days of operation. The engine will deyelop
at least 95% of maximumhorsepower when friction is
reduced to a minimum.
For continuous operation, allow 20% of horsepower
shown as a safety factor.
STARTING and OPERATING INSTRUCTIONS
Engines that are enclosed in a sheet metal house, as
shown in bottom view of Fig. 1, are called power
units. Others are furnished without a house, as shown
in top view of Fig. 1, and are called open engines.
On engines with a house, the side doors must
always be removedwhenoperating.
This is necessary for circulating sufficient air for
cooling the engine.
LUBRICATION
Before starting a new engine, fill the oil base with
good "gasoline engine" oil, as specified in the =Grade
of Oil" chart. Fill through the breather tube shown in
Fig. 3, with 4 quarts of oil.
For run-in of newengines, use same oil as recom-
mendedin Grade of Oil Chart.
After the engine has been run for a short time, the oil
lines and oil filter will have been filled with oil. Shut

GRADEOF OIL
SEASONORTEMPERATURE
Spring,Summeror Fall
+ 120°F to + 40°F
Winter
+ 40°F to + 15°F
+ 15°F to 0°F
BelowZero
GRADEOFOIL
SAE30
SAE 20-20W
SAE 10w
SAE 5W-20
UseOils classified as Service SE, SF, SGor CC
Crankcase
Capacity
Newengine 4 Qts.
Oil andfilter change 4 Qts.
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. The standard dip
stick location is below the oil filler-breather tube, but
can be located on starting motor side upon request.
Use only high-grade highly refined oils, corresponding
in body to the S. A. E. (Society of Automotive En-
gineers) Viscosity Numbers listed in Grade of Oil
Chart.
SERVICE CLASSIFICATION OF OIL
In addition to the S.A.E. Viscosity grades, oils are also
classified according to severity of engine service. Useoils
classified by the Americal Petroleum Institute as Serviae
SE, SFor SG. These types ofoil are for engines performing
under unfavorable or severe operating conditions such as:
high speeds, constant starting and stopping, operating in
extreme high or low temperatures and excessive idling.
Follow summer recommendations in winter if engine is
housed in warm building.
Checkoil level every 8 hoursof operation.
The old oil should be drained and fresh oil added
after every 50 hoursof operation.
To drain oil, remove drain plug illustrated in Fig. 3.
Oil should be drained while engine is hot, as it will
then flow more freely.
OIL PRESSURE
At engine operating temperature, the oil pressure will
be about 4 to 5 pounds per square inch, and due to
this low pressure system, an oil pressure gauge is
not required. When the engine is cold the pressure
will be higher, and a relief valye is fitted to the oil
pump so that under these conditions the maximum
pressure will be limited to 15 pounds.
FUEL
These engines can be furnished with either a gravity
feed tank mounted above the carburetor fuel level, a
side mount tank, or tank mounted below the engine.
In the latter two cases, a fuel pump is furnished.
The fuel tank should be filled with a good quality
gasoline free from dirt and water. The capacity of the
tank is approximately 6 gallons. Some of the poorer
grades of gasoline contain gum which will deposit on
valve stems, piston rings, and in the various small
passages in the carburetor, causing serious trouble
in operating and in fact might prevent the engine from
operating at all.
Use only reputable, well known
brands of Unleaded gasoline.
The gasoline should have an octane rating of at least 87.
Lowoctane gasoline will cause the engine to detonate, or
knock, and if operation is continued under this condition,
cylinders will score, valves will burn, pistons and bearings
will be damaged, etc.
Besure that air vent in tank cap is not pluggedwith dirt, as
this wouldprevent fuel from flowing to the carburetor.
FUELPUMPand PRIMING (Fig. 4)
The diaghragm type fuel pump, furnished on engines
with side mount or underslung fuel tanks, is actuated
by an eccentric on the camshaft, as illustrated in
cross section of engine, Fig. 2.
Hand Primer for hand crank engine is an accessory
furnished only upon request, and is a necessary func-
tion when starting a new engine for the first time, or
when engine has been out of operation for a period of
time. Gravity feed and electric start engines do not
require hand priming.
Whenpriming, a distinct resistance of the fuel pump
diaghragm should be felt when moving the hand lever
up and down. If this does not occur, the engine should
be turned over one revolution so that the fuel pump
drive cam will be rotated from its upper position which
prevents movement of the pump rocker arm.
Assuming the gasoline strainer is empty, approximate-
ly 25 strokes of the primer lever are required to fill
the bowl. See Fig. 4. After strainer bowl is full, an
addiUonal 5 to 10 strokes are required to fill the
carburetor bowl. When carburetor is full the hand
primer lever will move more easily.
Fig.4

IGNITION SWITCH
Magnetoignition is standard on these engines, with a lever
typeswitchonthesideofthemagneto,whichisalwaysinthe
onorrunningposition,exceptwhendepressedforstopping
theengine.SeetopviewofFig.].
Onpowerunit engines, a push button ignition switch is
mountedon the outsideof the housepanelat the flywheelend.
See bottomviewof Fig. 1. Whenstarting engine, the ignition
switchbuttonis pulledout. Tostop, pushin. Thiswill apply
to both magnetoandbatteryignition systems.
STARTING
Maintaina safe distance frommoving
parts of equipment.Knowhowto stop
the enginequickly in case of emergency.
/~ WARNING
Donotoperateenginein a closedbuild-
ingunlessit is properlyventilated.
/~ WARNING
STARTING PROCEDURE
1. Checkcrankcaseoil level andgasoline supply. Openfuel
shut-offvalvein fuel strainer or tank.
2. Disengageclutch, if furnished.
Pull variable speedcontrol ’/"handle out abouthalf-way
andlockin place. Witha twospeedcontrol, start in full
loadposition- idle after enginestarts.
4. Close choke by pulling choke button to extreme out
position.
5. Pull out ignition switchbuttonif tag reads ToStopPush
In’, or, turnignitionswitchto ’on’position.
6. Depressstarter switchto start engine,or, turn switchto
’start’ position.
IMPORTANT
Donot crank enginefor morethan 30 secondsat a time
if enginefails to start, wait about2 minutesbetween
crankingperiodsto preventstarter fromover-heating.
After enginestarts, pushchokebutton in gradually as
required for smoothrunning. Chokemustbe completely
open(button in ) whenengine is warmedup.
If flooding shouldoccur, openchokefully by pushingchoke
buttonin andcontinuecranking.Lesschokingis necessaryin
warmweather or whenengine is warm,than whencold.
WARM-UPPERIOD
The engine should be allowed to warmup to operating
temperaturebefore load is applied. This requires only a few
minutesof runningat moderatespeed.Racinganengineor
gunningit, to hurrythe warm-upperiod,is verydestructive
to thepolishedwearingsurfacesonpistons,rings,cylinders,
bearings,etc., as the properoil film onthesevarioussurfaces
cannotbe established until the oil has warmedupandbecome
sufficiently fluid. Thisis especiallyimportantonnewengines
andin cool weather.
Racinganengineby disconnectingthe governor,or by
doinganythingto interfere with the governorcontrolled en-
gine speed, is extremelydangerous.The govemoris pro-
videdas a meansfor controlling the enginespeedto suit the
load applied, andalso as a safety measureto guardagainst
excessivespeeds, whichmeasureto guardagainst excessive
speeds,whichnot onlyoverstrain all workingparts, but which
whichnot only overstrain all workingparts, but whichmight
causewreckingof the engineandpossibleinjury to bystanders.
All parts of the engineare designedto safely withstandany
speeds whichmight normally be required, but it mustbe
rememberedthat the stresses set upin rotating parts, increase
withthe squareof the speed.That meansthat if the speedis
doubledthe stressed will be quadrupled;andif the speedsare
trebled, the stresses will beninetimesas great.
Strict adherenceto the aboveinstructionscannotbe
too stronglyurged,andgreatly increasedenginelife
will resultasa rewardfor theseeasily appliedrecom-
mendations.
STOPPINGENGINE
Magnetoignition engines, less house,havea lever type stop
switchon the side of the magneto.Onthese, to etopengine,
depresslever andholddownuntil enginestops.
Powerunits andbattery ignition engines,are furnishedwithan
ignition switch, "ToStopPushIn".
If the enginehasbeenrunninghardandis hot, donot stop it
abruptlyfromfull load, but removethe load andallowengine
to runidle at 1000to 1200R.P.M.for three to five minutes.
This will reducethe internal temperatureof the enginemuch
faster, minimizevalve warping, andof course the external
temperature,including the manifoldandcarburetor will also
reducefaster, dueto air circulation fromthe flywheel.
Twomaintroubles resulting fromabruptly shutting off a hot
engineare vaporlockanddieaeling. Vaporlock will prevent
the flowoffuel in the fuel lines andcarburetorpassages,which
will result in hardstarting. This canbe overcomeby choking
the engine whencranking or waiting until the engine has
cooledoff sufficiently to overcomethe vaporlock.
Dieseling,is causedby the carbondeposits in the cylinder
headbeingheated upto suchan extent that they continueto
fire the engineandkeepit running after the ignition has
been shut off. Byidling the engine, as previously men-
tioned, the carbondeposits cool off, break upandwill blow
out throughthe exhaust.
9

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.
CARBURETOR ADJUSTMENT
The main metering jet in the carburetor is of the fix-
ed type, that is, it requires no adjustment. The idle
needle should be adjusted for best low speed opera-
tion, while carburetor throttle is closed by hand. For
illustrations and more information, see Carburetor
Manufacturer’s Instruction Bulletin in the back of
this manual.
MAGNETO BREAKER POINT ADJUSTMENT
Magnetos are properly adjusted before leaving fac-
tory. The breeker points on the Fairbanks-Morse mag-
neto and on the Wico magneto should be .0|5" at full
separation. If the spark becomes weak after continued
operation, it may be necessary to readjust these
points. To do this first remove the end cover on the
magneto. The crankshaft should then be rotated with
the starting crank, (this also rotates the magneto),
until the breaker points are wide open. The opening
or gap should then be measured with a feeler gauge
as shown in Fig. 8 and if necessary reset. To readjust
points, first loosen the locking screws on the contact
plate enough so that the plate can be moved. Insert
the end of a small screw driver into the adiusting slot
at the bottom of the contact plate and open or close
the contacts by moving the plate until the proper
opening is obtained. See Fig. 9. After tightening the
locking screws, recheck breaker point gap to make
sure it has not changed. If it is found that the breaker
points have become rough, they should be smoothed
with a breaker point file before the preceding adjust-
ments are made. Replace magneto end cover carefully
MEASURE BREAKER
POINT GAP WHEN~
OPEN. ADJUST TO
.015 INCH
BREAKER ARM-
LOCKING SCREWS
CONTACT PLATE~
ADJUSTING SLOT
OPENENDVIEW OF FAIRBANKS-MORSEMAGNETO
Fig.9
so that it will seal properly. Do not force cover screws
too tightly otherwise cover may crack. For further in-
formation, see Fairbanks-Morse or Wico Magneto
Maintenance Manual in the back of this manual.
MAGNETO IGNITION SPARK
If difficulty is experienced in starting the engine or
if engine misses firing, the strength of the ignition
spark may be tested by disconnecting the No. 1 igni-
tion cable from the spark plug and holding the ter-
minal about 1/8 inch away from the air shroud or any
other conveniently located metal part of the engine.
If the ignition cables have a molded rubber insulated
spark plug terminal at the end, as illustrated in Fig.
lO, wedge a piece of bare wire up into the terminal
and let one end of the wire extend out. Turn the en-
gine over slowly by the starting crank two complete
revolutions and watch for a strong spark discharge,
which should occur during the cycle at the instant the
impulse coupling on the magneto snaps. Repeat this
check with each of the other ignition cables. If there
is a weak spark, or none at all, check breaker point
opening as mentioned in preceding paragraph under
11

HOLEPLUG
Fig. lO
=Magneto Breaker Point Adjustment’. If this does not
remedy the trouble, it may be necessary to install a
new condenser. See Magneto Manufacturer’s Mainte-
nance Instructions in back of this manual.
FIRING ORDER
’The firing order of the cylinders is 1-3-4-2,and the
magneto and battery type distributor rotate at one-half
engine speed, as is the case with conventional =in
line" engines. The intervals between the firing of the
cylinders is 180 o. No. 1 cylinder is the one nearest to
the flywheel in the left bank of cylinders, when view-
ed from the flywheel end of the engine. No. 3 cylinder
is the other cylinder in this bank. No. 2 cylinder is
the one nearest to the flywheel in the right bank of
cylinders and No. 4is the other cylinder in this bank.
The cylinders are numbered from 1 to 4 on the air
shroud near the spark plugs. The flywheel end of the
engine is designated the front and the power take-off
end, the rear of the engine.
MAGNETa TIMING
The proper spark advance is 23°. To ,check timing
with a neon light, the running spark hdvance is indi-
cated by a 3/8 inch slotted hole in the rim of the air
intake screen, 68° left of the flywheel shroud verti-
cal centerline, marked VH, or if screen is removed,
time to the lower half of the 1/4 inch elongated hole
on the face of flywheel shroud 23° below the center-
line of No. 1 and No. 3 cylinders as illustrated in
Fig. 11. The end of the ’X’ marked vane should be
whitened with chalk or paint for this operation.
To Time hiagneto to Engine: Remove air intake
screen to expose timing ,marks on both flywheel and
shroud. See Magneto Timing Diagram, Fig. 11.
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.
Whenthe air blows out o,f the No. 1 spark plug hole,
continue turning the crank until the edge of the mark-
ed vane on flywheel is on line with the mark on the
~ertical centerline of the shroud as shown on Fig. 11.
Leave flywheel in this position. At this point the
~e),way for mounting the flywheel is also on top.
Reassemble spark plug.
Next, remove the inspection hole plug from the mag-
neto timing opening, located in the gear cover as
shown in Fig. 10.
Assuming that the magneto has been removed from
the engine, the following procedure should be follow-
ed before remounting.
The Number1 cylinder firing position of the magneto
must be determined. Insert the ignition cable into the
No. 1 tower terminal of the magneto end cap and hold
the spark plug terminal at the other end, about 1/8"
away from the magneto body. Turn the magneto gear
in a clockwise rotation, tripping the impulse coupling,
until the No. 1 terminal sparks, then hold the gear in
this position. Mount the magneto to the engine, mesh-
ing the gears so that when the magneto is in place,
the gear tooth marked with an ’X’ will be visible
through the lower half of the inspection hole in the
gear cover, as shown in Timing Diagram, Fig. 11.
Tighten the nut and capscrew for mounting the mag-
neto to the gear cover, making sure the magneto
flange gasket is in place.
The No. 1 terminal is identified on the magneto cap.
The terminals follow the proper firing order of 1-3-4-2
in a clockwise direction viewing the cap end. The
leads from the magneto should be connected to spark
plugs of corresponding numbers.
No. 1 cylinder is the cylinder nearest the fan-flywheel
of the engine in the left bank and No. 3 cylinder is the
other cylinder in that bank. No. 2 cylinder is across
the engine from No. 1 and No. 4 is across from No. 3.
Whenthe magneto is properly timed the impulse coup-
ling will snap when the ’DC’ and ’X’ marked vane of
the flywheel, line up with the mark on the flywheel
shroud which indicate the centerline of the No. 1 and
3 cylinders. This can be checked by turning crank-
shaft over slowly by means of a hand crank. The im-
pulse will also snap every 180° of flywheel rotation
thereafter.
DISTRIBUTOR - BATTERY IGNITION
Onengines equipped with Flywheel Alternator or belt driven
alternator, battery ignition is used in place of magnetoigni-
tion. The distributor is of the automatic advance type, and
rotor turns at one-half engine speed in a counterclockwise
direction.
12

No. 1 TERMINAL INDICATED ON
MAGNETO END CAP AS SHOWN.
OTHER TERMINALS FOLLOW FIR-
ING ORDER IN CLOCKWISE ROTA-
TION.
NO 9--
NO 4
~N O 3
VERTICAL CENTERLINE
MARK ON SHROUD FOR
TIMING MAGNETO.
’X’ MARKED VANE ON
FLYWHEEL
0
CRANKSHAFT GEAR
RUNNING SPARK ADVANCE
FOR CHECKING WITH NEON
LIGHT. -
~MARKED GEAR TOOTH, VISIBLE
~THUS THROUGH OPENING, WI EN
FLYWHEEL IS LOCATED AS
~ DICATED ABOVE.
MAGNETO GEAR
EDGE OF VANE IN LINE WITH
MARK ON SHROUD WHEN TIM-
ING MAGNETO.
1 CRANKPtN
~N~_3 CR~,NKPIM
FLYWHEEL KEYWAY
ON TOP
2 CRANKPtN
Fig. 11, MAGNETOTIMING DIAGRAM
Thedislributor is mountedto anadapterattached to the gear
cover, or TopMounted- attachedto the governorhousing.
removingscreen. To makea stationary checkof the
timing-removethe screen over the flywheel air intake
openingby taking out the screwsholding the screen in
Thespark advance for normalspeeds is 23°, the same
as for magnetoignition. Engine must be running at
2000R.P.M. or over whenadjusting spark advance.
ELECTRICAL WIRING CIRCUITS
NOTE:Beginning with engine serial No. 3987113, the
standardwiringcircuits for all 12voltelectrical equipmentis
negative ground polarity, in place of the previously
furnished positive ground. All 6 volt systems remain
positive ground.
TheFlywheelAlternator circuit illustrated in Fig. 12
alwayswasandis a negative groundsystem. It replaces
the previously furnished gear driven generator which
wasavailable both negative and positive ground.
Wiringdiagramandservice parts informationfor obso-
lete gear driven type generator can be obtained by
writing Wisconsin Motors, LLC,Memphis,TN38133.
DISTRIBUTOR TIMING
Aslotted opening has been added to the rim of the
flywheel screen to check runningsl~rk advan¢~without
RECTIFIER d~ ~ REGULATOR
MODULE
~
=~_z/ ~ULE
12 VOLT ~--~ ~ ~
AUTO.TIC I ~ ~,C~nne~i~,, h ’ --
~u~ ~_ ¯ ~~ ~ConnB~ionsor LJgIs’~
~. Ial chargesideo1 ammeter
~’ ~ (negativeterminal).
~ Conne~ E~uipment
~Jenoids Rer~
SPARKPLUGS,
DISTRIBUTOR
DRIVE
Ht-TEMP SWITCH~
(optional)
A
r .... "~.~" .......
START
,, SWITCH
,,(optionol)
SOLENOID
SWITCH
(optional)
STARTING MOTOR
Fig. 12, WIRINGDIAGRAM,
25ampFlywheelAlternatorandBatteryIgnition
13

NEON LAMP TIMING
The engine should be timed to the 23° advanced
position at not less than 2000R.P.M.
Thetiming should be checked with a neon lampconnected
in series withNo.1 sparkplug. Chalkor paint the endof the
"X" markedvane on Ihe flywheel, white. Thenwith the
engine operating at 2000R.P.M.or over, allow the flash
fromthe neonlampto illuminate the whitenedvane. At the
time of the flash, the leading edgeof the vaneshouldline
up with the lower half of the running spark advance
timingholeon the flywheelshroud, see Fig. 13. If it does
not, the advance arm clamp screw should be loosened,
and the distributor body turned slightly clockwise or
counterclockwise,as required, until the whiteflywheelvane
matchesup with the lower half of the advancetiming hole.
Be sure advance arm clamp screw is then carefully
tightened. If the engineis runningbelow2000R.P.M.when
timing, the automaticadvancein the distributor will not be
fully advancedandthe inaccurate timing maycause serious
damageto the engine whenoperating at high speeds. Mount
flywheel screen if removed- use slotted openingwithout
removingscreen for running spark advancecheck only.
POINT TYPE IGNITION DISTRIBUTOR
Thedistributor breaker point gapshould be .018 to .022
inches. Toreadjust breaker point gap, turn engineover by
meansof the starting crankuntil the distributor breakerarm
rubbingblock is on a high point of the cam. Loosenthe
stationary contact locknut andscrewfixed contact, in or
out, until correct gap is obtained. Tightenlocknut and re-
checkgap.
SOLID STATEIGNITION DISTRIBUTORS
ManyWisconsinenginesare nowbeing equippedwith a solid
state ignition distributor. Detailedtroubleshooting,repair and
parts informationcan be found in the rear section of this
manual.
CHARGING SYSTEM
Enginescanbeequippedwitha 10 amp,25 amp,or 30 amp
flywheelalternatorsystemor a 37ampbelt drivenalterna.
tor.Instructionsarelocatedin therearof this manual.
RESTORING COMPRESSION
In a newengine or onewhichhasbeenout of operationfor
sometime, oil mayhavedrained off the elyinders so that
compressionwill be weak,causingdifficulty in starting. To
remedythis condition, removethe spark plugsandpourabout
a fluid ounceof crankcaseoil throughthesparkplugholeinto
eachcylinder. Turnengineover several timeswiththe hand
crankto distribute oil overthe cylinderwails. Assemblespark
plugs andcompressionshouldbe satisfactory.
SETGAP
Fig.16
SPARKPLUGS,Fig. 16
Incorrect gap, fouled or worn spark plug electrodes,
will have an adverse affect on engine operation. Re-
movespark plugs periodically, clean, regap or replace
if necessary. Threadsize is 18 ram.
Sparkpluggap- 0.030of aninch.
Replacementplugs must be of the correct heat range,
like Champion No. D-16J, ACNo. C86 commercial.
Tighten spark plugs, 25 to 30 {oat pounds torque.
HIGH TEMPERATURESAFETY SWITCH
As a safety precaution against overheating, engines
can be equipped with a high temperature switch
mountedto the cylinder head at the No. 4 spark plug.
Whencylinder head temperature becomes critically
high, the safety switch will automatically stop the en-
gine by shorting out the ignition system. A waiting
period of about 10 minutes will be required before the
switch has cooled off sufficiently to re-start the en-
gine. Anoverheated engine will score the cylinder
walls, burn out connecting rod and crankshaft bear-
ings, also warp pistons and valves. The cause of the
overheating condition will have to be remediedbefore
the engine is re-started. See EngineOverheatspara-
graph in Troubles, Causes and Remedies section.
Service Kit is available - see parts list section.
KEEP ENGINE CLEAN-PREVENT OVERHEATING
(AgriculturalandIndustrial Engines)
This engine is cooled by blasts of air which must be
allowed to circulate all around the cylinders and cyl-
inder heads to properly cool the engine and thereby
keep it in good running condition. If dust, dirt or
chaff is allowedto collect in the cylinder shrouding
or in the V betweenthe cylinders, it will retard the
flow of air and cause the engine to overheat. Keep
flywheelscreenandrotating screenclean, so as not
to restrict the intake of cooling air.
With reference to Fig. 17; follow the cleaning and
maintenance instructions pointed out, to obtain
trouble fre~ and satisfactory engine performance.
1. Removethese covers frequently and clean out all
dust, dirt and chaff. Be sure to replace covers.
15

Fig.17
2. Open these covers frequently and clean out all
dust and chaff. Be sure to close covers.
3. Keep this space between cylinders free of dust
and chaff.
4. Read instructions on this air cleaner regarding its
care. This is important. The entire air cleaner
should be removed from the engine at least once a
year, and washed in a cleaning fluid to clean out
dirt gathered in the back fire trap in the top part
of the air cleaner.
5. Empty pre-cleaner of accumulated dust and dirt
frequently. Do not use oil or water in pre-cleaner,
this must be kept dry.
6. Replace this oil filter cartridge every other oil
change. If operating conditions are extremely dusty
replace cartridge every oil change. Be sure that
your replacement is a Wisconsin Micro-Fine filter.
7. Do not allow shrouding to become damaged or bad-
ly dented as this will retard air flow.
Never operate engine with air shrouding re-
moved.This will retard air cooling.
Always keep all parts of the engine clean.
This will prolong engine life, and give more
satisfactory operation.
Every 4 to 8 hours, depending on dust conditions,
check air cleaner and change oil. See Page lO.
Every 8 hours check crankcase oil level, Keep filled
to full mark on oil gauge sabre, but no more. See
Fig. 3.
Every 50 hours drain crankcase and refill with fresh
oil. See Lubrication, Pages 6 and 7.
TROUBLES
CAUSESANDREI~EDIES
Three prime requisites are essential to starting and
maintaining satisfactory operation of gasoline en-
gines. They are:
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 en-
gine 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. These conditions mayaffect the starting, but do
not necessarily mean that the engine is improperly
adjusted.
As a guide to locating any difficulties which might
arise, the following causes are listed under the three
headings: Fuel Mixture, Compression, and Ignition.
In each case, the causes of trouble are given in the
order in which they are most apt to occur. In many
cases the remedy is apparent, and in such cases no
further remedies are suggested.
STARTINGDIFFICULTIES
FUEL MIXTURE
Nofuel in tank or fuel shut-off valve closed.
Fuel pump diaphragm worn out, so pump does not
supply carburetor with fuel.
Carburetor not choked sufficiently, especially if en-
gine is cold. See ’Choke’, Page 9.
Water, dirt, or gum in gasoline interfering with free
flow of fuel to carburetor.
Poor grade or stale gasoline that will not vaporize
sufficiently to form the proper fuel mixture.
Carburetor flooded, caused by too much choking
especially if engine is hot. See ’Choke’, Page 9.
Dirt or gum holding float needle valve in carburetor
open. This condition would be indicated if fuel con-
tinues to drip from carburetor with engine standing
idle. Often tapping the float chamber of the carbu-
retor very lightly with the handle of a screw driver or
similar tool will remedy this trouble. Do not strike
carburetor with any metal tools, it may cause serious
damage. Also if the mixture in the cyhnder, due to
flooding, is too rich, starting maybe accomplished by
continued cranking, with the carburetor choke open.
If, due to flooding, too much fuel should have enter-
ed the cylinder in attempting to start the engine, the
mixture will most likely be too rich to burn. In that
case, the spark plugs should be removed from the cyl-
inders and the engine then turned over .several times
with the starting crank, so the rich mixture will be
blown out through the spark plug holes. The choke on
the carburetor should of course be left open during
this procedure. The plugs should then be replaced
and starting tried again.
16