Oil Pump: Description and Operation

The oil pump has the following characteristics:
^ It is a positive-displacement internal gear pump using top seal rotors (known as a G-rotor oil pump).
^ It is mounted on the front face of the cylinder block.
^ The inner rotor is piloted on the crankshaft post and is driven through flats on the crankshaft.
^ System pressure is limited by an integral, internally vented relief valve that directs the bypass oil back to the inlet side of the oil pump.

Oil pump displacement has been selected to provide adequate volume to ensure proper oil pressure at both hot idle and maximum speed.

Relief valve calibration protects the system from excessive pressure during high-viscosity conditions, yet is designed to provide adequate lubrication under high-temperature and high-speed conditions.