1967 - 1968 Corvette: Engineering Service Note: New Push Rod Assembly for M4 Corvette
Subject: New Push Rod Assembly for M4 Corvette
Model and Year: 1968 and Pass L88 Corvette & H.D. Service (#846) (T.N.)
Source: Chevrolet Engineering Service Letter - UPC VI - Engine
Page Number: NA
Date: May 1968
Valve train failures have been reported on Corvettes equipped with mechanical cam 430 HP engine during high engine speed type operation.
Field complaints state present ball and push rod assemblies fail due to the welded on ball coming off at high speed.
To correct this condition, engineering has released a new insert type end push rod assembly for production.
New inlet and exhaust push rod assemblies will enter production as soon as available.