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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Description of Compression Readings

AllData Editors Note - Ford does not provide a cranking pressure specification, only an acceptable range.

Cylinder compression pressure should range between 134 psi (being the lowest maximum pressure), and 250 psi (being the highest maximum pressure), at an minimum engine cranking speed of 180 RPM. The compression in each cylinder should fall within the specified compression pressure range with the lowest cylinder reading being at least 75% of the highest.