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

Pressure/Variation

Compression Test Data For Engine At Normal Operating Temperature
Minimum compression pressure approx. 12 bar (176 psi)
Low compression approx. 7.5 bar (110 psi)
Allowable difference between cylinders max. 1.5 bar (22 psi)