Engine Lubrication: Description and Operation

DESCRIPTION
The engine lubrication system is of the force-feed type.
- Oil is supplied under full pressure to the crankshaft and connecting rod bearings, hydraulic valve tappets and camshaft bearings.
- From the valve tappets, a controlled volume of oil is supplied to the rocker arms through the hollow push rods.
- All other moving parts are lubricated by gravity flow or splash.

OIL PUMP
The rotary spur-type oil pump, which develops the oil pressure, is bolted to the No. 4 crankshaft main bearing cap. The spur-driven gear is rotated by the camshaft position sensor housing shaft through an oil pump intermediate shaft. Flexible fuel vehicles are equipped with a unique oil pump with a stainless steel oil pick-up screen.

OIL FILTER
A full-flow oil bypass filter is externally mounted on the cylinder block and normally all engine oil passes through the oil bypass filter. However, if the oil filter element should become restricted, a spring-loaded bypass valve will open and allow an uninterrupted flow of oil to the engine's moving parts.

OIL PAN
The oil pan is a stamped steel part that bolts to the bottom of the cylinder block.