The tank, piping, and carburetor should be drained more frequently in cold weather than in hot, to prevent any accumulation of water from freezing, and stopping the fuel supply. A gasoline strainer should always be supplied on the fuel line, and should be regularly drained.
The motor may often be made to start in cold weather by cutting out the spark, and cranking the engine two or three revolutions with the throttle wide open. The throttle should now be closed within ⅛ of its fully closed position, the ignition current turned on, and the engine cranked for starting. This system will very seldom fail of success at the first attempt.
Carburetor flooding is shown by the dripping of gasoline from the carburetor, and which results in too much gasoline in the mixture. Flooding may be caused by dirt accumulating under float valve, by a leaking float (Copper Float), by Water Logged Float (Shellac worn off Cork Float), by float adjustment causing too high a level of gasoline, by leaking float valve, by cutting out ignition when engine is running full speed, by rust or corrosion sticking float valve lever, by float binding in chamber, by float being out of the horizontal, by float valve binding in guide, by excessive pressure on gasoline, or by tickler lever held against float continuously.
Dirt accumulated under float valve may sometimes be flushed out by depressing tickler lever several times; if this does not suffice, the cap over the valve must be removed, and the orifice cleaned by wiping with a cloth.
LEAKING FLOAT VALVES should be reground with ground glass or very fine sand; never use emery as the particles will become imbedded in the metal, which will be the cause of worse leaks.
Should the shellac be worn off of a cork float allowing the gasoline to penetrate the pores of the cork, a new float should be installed, as it is a doubtful policy for owner to give the float an additional coat of shellac.
MISFIRING AT LOW SPEED. If the carburetor cannot be adjusted to run evenly on low speed after making all possible adjustments with the needle valve, the trouble is probably due to air leaks between the carburetor and engine, caused by broken gaskets, cracked brazing in the intake manifold, or by leaks around the valve stem diluting the mixture.
INCORRECT VALVE TIMING will cause missing, especially on multiple cylinder engines, as the carburetor cannot furnish mixture to several cylinders that have different individual timing. Look for air leaks around the spark edge openings, and be sure that all valves seat gas tight. Always be sure that the auxiliary air valve remains closed at low speeds, as a valve that opens at too low a speed will surely cause misfiring as it dilutes the mixture.
MISSING in one cylinder may be caused by an air leak in that cylinder.
WATER in gasoline will cause misfiring, especially in freezing weather, as it obstructs the flow of fuel to the carburetor. The carburetor and tank should be drained at regular intervals, and if possible, a strainer should be introduced in the gasoline line.