Full pressure lubrication, through a full-flow oil filter
is supplied by a gear-type oil pump. Oil is drawn
up through the oil pump screen and passes
through the pump to the oil filter. The oil filter is a
full-flow paper element unit with an anti-drain back
valve. An oil filter bypass valve is used to ensure
adequate oil supply, in the event the filter becomes
plugged or develops excessive pressure drop.
Filtered oil flows into the main gallery and then to
the camshaft, the balance shaft, the rear bearing,
and the crankshaft bearings.
The valve lifter oil gallery supplies oil to the valve
lifters. Oil flows from the valve lifters through the
hollow valve pushrods to the valve rocker arms. Oil
drains back to the crankcase through the oil drain
holes in the cylinder head. The camshaft timing
chain is drip fed from the front camshaft bearing.
The pistons and piston pins are lubricated by oil
Chevy 4.3L Vortec Engine Oiling System