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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Head Bolt Reuse/Replace

Outer Diameter of Cylinder Head Bolts





^ Cylinder head bolts are tightened by plastic zone tightening method. Whenever the size difference between d1 and d2 exceeds the limit, replace them with new one.
Limit (d1 - d2) More than 0.18 mm (0.0071 inch)
^ If reduction of outer diameter appears in a position other than d2, use it as d2 point.