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

Air Injection Check Valve: Testing and Inspection

1. Remove check valve(s) from vehicle.
2. Blow through check valve in direction of air manifold or cylinder head, then attempt to suck back in reverse direction. Air flow should only be towards air manifold or cylinder head. If not, replace check valve.