LUBE OIL PRESSURE REGULATOR - MAINTENANCE INSTRUCTIONS.
a. Stabilized lubricating oil pressure is maintained within the engine at all speeds, regardless of oil temperature, by
means of a regulator installed between the oil pump outlet pipe and the cylinder block.
b. The regulator assembly consists of a body, a hollow piston-type valve, a compression spring, and a plug to retain
the spring in the body.
c. The valve is held on its seat by the spring, which is compressed by the plug screwed into the valve opening in
the regulator body. The entire assembly is bolted to the lower flange of the cylinder block and sealed against oil leaks by
a gasket between the two members. When conditions are such that the oil pressure at the valve exceeds 50 pounds per
square inch (35.2 kg/cm sq) the valve is forced from its seat and oil from the engine gallery is by-passed to the engine oil
pan. Thus, stabilized lubricating oil pressure is maintained at all times regardless of oil temperature.
d. Under normal conditions, the pressure regulator should require very little attention. If sludge has been allowed to
accumulate in the lubricating system, the valve may not work freely, thereby remaining open or failing to open at the
normal operating pressure.
e. Whenever the lubricating oil pump is removed for inspection, the regulator valve and spring should also be
removed, thoroughly cleaned in fuel oil and inspected.