Engine Lubrication: Description and Operation

DESCRIPTION
The engine lubrication system is of the force-feed type in which oil is supplied under full pressure to the crankshaft, connecting rod bearings and timing chain tensioners. The flow of oil through the valve tappets and valve train is controlled by a restricting orifice located in the head gaskets.

OIL PUMP
The lubrication system is designed to provide optimum oil flow to critical components of the engine through its entire operating range. The heart of the system is a positive displacement internal gear oil pump. Generically this design is known as a G-rotor pump. The inner rotor is piloted on the crankshaft post and is driven through the crankshaft.

RELIEF VALVE/SYSTEM PRESSURE
System pressure is limited by an integral, internally vented relief valve which directs the bypassed oil back to the inlet side of the oil pump.
- Oil pump displacement has been selected to provide adequate volume so there is proper oil pressure both at hot idle and maximum speed.
- Relief valve calibration protects the system from excessive pressure during high viscosity conditions, yet is designed to provide adequate connecting rod bearing lubrication under high temperature and high speed conditions.

OIL PAN
The oil pan is cast aluminum and is attached to the cylinder block and transmission. The oil pan acts as a reservoir holding lubricating oil that is pumped through the engine by the oil pump after start up.