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

Piston Ring Groove Depth
No. 1 4.640 - 4.784 mm (0.182 - 0.188 inch)
No. 2 4.575 - 4.719 mm (0.180 - 0.185 inch)
No. 3 4.097 - 4.236 mm (0.161 - 0.166 inch)
Piston Ring Gap
Top Compression Ring 0.25 - 0.51 mm (0.0098 - 0.020 inch)
2nd Compression Ring 0.23 - 0.48 mm (0.009 - 0.018 inch)
Oil Control (Steel Rails) 0.25 - 0.64 mm (0.0098 - 0.025 inch)
Piston Ring Side Clearance
Top and Second Compression Rings 0.030 - 0.080 mm (0.0011 - 0.0031 inch)
Oil Ring (Pack) 0.012 - 0.178 mm (0.0004 - 0.0070 inch)
Piston Ring Width
Compression Rings 1.47 - 1.50 mm (0.057 - 0.059 inch)
Oil Ring (Pack) 2.72 - 2.88 mm (0.107 - 0.1133 inch)