GM Astro/Safari 1985-1996 Repair Guide

Knocking Valves


When the valves are constantly noisy, replace or repair the following items or systems, as necessary:

Unadjusted valve lash.
Valve springs may be broken.
Pushrods may be bent.
Camshaft lobes may be excessively worn.
Dirty or worn valve lifters.
Valve guides may be worn.
Valve seat or face runout may be excessive.
Loose rocker arm studs.