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
Specified Compression Value 10.0-12.0 bar (145-174 psi)
Minimum Compression Value approx. 8.5 bar (123 psi)
Permissible difference between cylinders 1.5 bar (22 psi) max.