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

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Piston: Testing and Inspection

1. Inspect outer circumferences of all pistons for seizure or scoring. Replace if necessary.
2. Measure piston to cylinder clearance. Desired clearance is 0.0015-0.0020 inches. Maximum clearance for all rings is 0.006 inches.
3. If clearance exceeds maximum specification, replace piston or rebore cylinders to fit oversize pistons.
4. Piston pin hole diameter is 0.7870-0.7874 inches. Piston pin diameter is 0.7869-0.7871 inches and piston pin clearance is 0.0001-0.0005 inches. Replace piston and piston pin as a matched set.
5. Measure piston ring to ring band clearance around entire circumference using a new piston ring.
6. Desired clearance is 0.0012-0.0025 inches for top ring, and 0.0012-0.0027 for second ring.
7. Maximum clearance on all rings is 0.006 inches. Replace piston if clearance exceeds maximum.
8. Inspect piston rings for damage, abnormal wear or breakage. Replace if necessary.