OVERSIZE TAPPET BORES IDENTIFICATION

VEHICLES AFFECTED: 1983-84 'J' Series and 'S/T' Trucks with 2.0L Engines (Codes P, Y)

Some Tonawanda built 2. 0L L4 LQ2 and LQ5 engines may have been produced with 0.26mm oversize tappet bores. The oversize tappet bore is identified with a vertical stripe of white paint on both sides of the tappet bore inside the tappet cavity. In addition, the cylinder block has a steel stamp with '.26 OS' on the top right front machining pad. If one of the oversize hydraulic valve lifters requires replacement, use P/N 5233545.

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