Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

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Oil Filter: Description and Operation

NORMAL OPERATION
A full-flow oil bypass filter is externally mounted on the cylinder block and normally all engine oil passes through the oil bypass filter.

ABNORMAL OPERATION
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.