GENERAL DESIGN
Wisconsin engines are of the fou r cycle type, in which each of the four operations of suction, compression, expansion and exhaust constitutes a complete stroke. This gives one power stroke for each two revolutions of the crankshaft

COMPRESSION RELEASE
A component part of the camshaft that operates automatically and trouble free. Permits fast and effortless starting with no dangerous "kick-back". Incorporated in these models of engines beginning with Serial No.4225490.

ROTATION
The rotation of the crankshaft is clockwise when viewing from the flywheel or starting end of the engine. This gives counter-clockwise rotation at the power take-off end of the crankshaft.

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.

HORSEPOWER

COOLING
Cooling is accomplished by a flow of air, circulated over the cylinder and head 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 shrouding removed, because this will retard the air cooling.

Keep the cylinder and head fins free from dirt and chaff. Improper circulation of cooling air will cause engine to overheat.

CARBURETOR
The proper combustible mixture of gasoline and air is furnished by a balanced carburetor, giving correct fuel to air ratios for all speeds and loads.

IGNITION
The spark for ignition of the fuel mixture is furnished by a high tension flywheel magneto. A stator plate functions as an engine bearing plate as well as a support for the coil and core. The permanent magnet is mounted to the flywheel, and a breaker box on the side of the crankcase contains the points, condenser and stop switch. A push pin, actuated by the engine camshaft, operates the breaker arm at half engine speed.

Battery ignition (12 volt) can be furnished in place of magneto, when specified. An ignition coil and breaker assembly are the means of inducing high voltage to the spark plug. Battery is not furnished by Wisconsin Motor Corporation.

LUBRICATION SYSTEM
An oil dipper attached to the connecting rod provides for a splash type lubrication system. The action of the dipper striking the oil in the crankcase provides ample lubrication for all internal parts of the engine.

GOVERNOR
A governor of the centrifugal flyball 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 or variable speed control, to regulate the governed speed of the engine.

For each inch lower the Barometric pressure drops, there will be a loss in horsepower of 3 1/2%.

For each 10 degrees temperature rise there will be a reduction in horsepower of 1%.

For each 1000 ft. altitude above sea level there will be a reduction in horsepower of 3 1/2%

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 maximum power when shipped from the factory. The power will increase as friction is reduced during the first few days of operation. The engine will develop at least 95% of maximum horsepower when friction is reduced to a minimum.

For continuous operation, allow 20% of horsepower shown as a safety factor.

INSTRUCTIONS FOR STARTING AND OPERATING

LUBRICATION
Before starting a new engine, fill crankcase base with the correct grade of engine oil, as specified in "grade of oil chart". Fill thru the filler plug opening, illustrated in Fig. 4, with 2 quarts of oil. For run-in of new engines, use same oil as recommended in Grade of Oil Chart. The oil level is indicated by a groove on the dip stick, as shown in Fig. 4. Check oil level by resting bottom of plug at the top of oil filler opening on gear cover. (Do not thread in place to check oil).

Too much emphasis cannot be given to the matter of oil selection. High grade oil of the body suited to the requirements of your engine is the most important single item in the economical operation of the unit, yet it is the cheapest item of operating cost. Select your oil solely on equality and suitability - never on price.

High-grade highly refined oils, corresponding in body to the S. A. E. (Society of Automotive Engineers) Viscosity Numbers listed in Grade of Oil Chart, will prove economical and assure long engine life.

SERVICE CLASSIFICATION OF OIL
In addition to the S.A.E. Viscosity grades, oils are also classified according to severity of engine service. Use oils classified by the American Petroleum Institute as Service MS, SD or SE. This type of oil is 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.

Check oil level every 8 hours of operation.

The old oil should be drained and fresh oil added after every 50 hours of operation.

To drain oil; remove drain plug at either side of crankcase base. Oil should be drained while engine is hot, as it will then flow more freely.

FUEL
The fuel tank should be filled with a good quality gasoline free from dirt and water. The capacity of the standard tank is 1 1/2 gallons. A larger, 2 3/4 gallon tank, can be furnished upon request. 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 gasoline of the REGULAR GRADE.

FUEL PUMP
An engine equipped with fuel pump; when starting for the first time, or when engine has been out of operation for a while, should be primed to prevent hard starting. Disconnect ignition wire at the spark plug, then turn the engine over about 6 or 7 times by means of the rope starter sheave to actuate the fuel pump and thus fill the carburetor bowl with gasoline. Be sure and connect ignition wire after priming has been accomplished.

Fuel pump is an optional accessory and is usually furnished only upon request when engine is ordered. But, beginning with Serial No. 4080373, all crankcases for these models of engines are machined to accomodate field installation of a fuel pump. Instructions for fuel pump maintenance and repair are located in the back of this manual.

STARTING

STARTING PROCEDURE (Fig. 5 and Fig. 6)
1. Check crankcase oil level and gasoline supply. Open fuel shut-off valve.
2. Disengage clutch, if furnished.
3. Set throttle about 1/2 open, if variable speed governor control is furnished. With a fixed speed governor, spring will hold throttle open for starting. e