Gas in the oil?

This is a common problem with gravity flow fuel systems when you do not shut the fuel off after use. If the float/needle valve sytem in the carburetor does not seal correctly every time gasoline will flow past the valve overfilling the float bowl.

Updraft carburetors for gravity flow systems were built with a bronze filter/plug in the bottom of the air horn to allow excess gasoline to drip onto the ground. If, as is common on old equipment, this plug is gummed up or otherwise plugged, and the air filter hose is securely connected and in good condition, the excess gasoline will fill up the intake manifold and eventually run into the cylinders through open intake valves. Once in the cylinders, it will flow past the rings into the crankcase.

The remedy is to shut off the fuel after use and/or overhaul the carburetor.

Dean