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

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

Or, hide this message: temporarily or permanently

Compression Check: Specifications

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

Compression pressure should be checked with the engine at normal operating temperature, spark plugs removed and throttle plate in wide open position. Crank the engine at least five compression strokes and record highest reading for each cylinder. The indicated compression pressures are considered within specification if the lowest reading cylinder is within 25°of the highest.