Low oil pressure

Insufficient or poor oil supply to valve train.

1. Perform oil pressure test.
2. Repair or replace all damaged components.

Improper lubrication to the valve rocker arms

1. Inspect valve rocker arm and shaft, valve pushrod, oil filter bypass valve, oil pump and pump screen, and engine block oil galleries.
2. Repair or replace all damaged components.

Excessive valve lash

1. Check the valve lash adjustment, and correct if above specifications.
2. Repair or replace all damaged components.

Worn pushrod upper end ball

1. Inspect pushrod end ball.
2. Repair or replace all damaged components.

Bent valve pushrod

1. Inspect valve pushrod and valve rocker arm.
2. Repair or replace all damaged components.

Loose, worn or damaged valve rocker arm

1. Inspect valve rocker arm and rocker arm shaft.
2. Repair or replace all damaged components.

Loose valve rocker arm attachments

1. Inspect valve rocker arm and rocker arm shaft.
2. Repair or replace all damaged components.

Broken valve springs

1. Inspect valve springs.
2. Repair or replace all damaged components.

Worn and/or damaged valve spring shims, seats, or keys

1. Inspect valve spring shims, seats, and keys.
2. Repair or replace all damaged components.

Sticking valve

Carbon on the valve stem or valve seat may cause the valve to stick.

1. Inspect valves and valve guides.
2. Repair or replace all damaged components.

Missing or improperly positioned lifter guides

1. Inspect lifter guides.
2. Repair or replace all damaged components.

Worn or faulty camshaft lobes

1. Inspect camshaft lobes.
2. If damaged replace camshaft and all lifters.

Worn valve guide

1. Inspect the valves and valve guides.
2. Repair or replace all damaged components.

Damaged or misaligned timing gears

1. Inspect timing gears.
2. Replace all damaged components.