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

Piston Ring, Engine

Compression Rings
Side Clearance:
Top Groove 0.05-0.027 mm (0.0019-0.0027 inch)
Second Groove 0.05-0.027 mm (0.0019-0.0027 inch)
Ring Gap:
Top 0.25-0.50 mm (0.010-0.020 inch)
Second 0.25-0.50 mm (0.010-0.020 inch)

Oil Ring
Groove Clearance 0.05-0.021 mm (0.0019-0.0082 inch)
Gap 0.25-0.76 mm (0.010-0.040 inch)