The lubricating oil system serves a dual purpose by furnishing oil to the engine for cooling the pistons and lubricating the various bearings and wearing parts under pump pressure. Refer to the piping diagram on the following page and to the drain and fill diagram in Sec. The engine driven lubricating oil pump draws oil from the engine crankcase thru a coarse strainer, and pumps it thru the 6-element filter to the oil cooler. Here, the oil is circulated around water cooled tubes and then piped thru a fine strainer to the engine oil headers.
Flow continues thru the engine parts and back to the crankcase.
At idling speed all oil is designed to flow thru the 6-element filter. At higher engine speeds a relief valve will open at 20-25 lbs. Plugging of the oil cooler or strainer will open an internal by-pass in the pump and cause the engine to shut down from low oil pressure if sufficient drop occurs. The pump relief valve is set at 70 lbs. An oil line from the lower engine lubricating oil header to the engine governor provides connection to the low oil pressure shutdown feature located in the governor.