Low oil pressure

1. Perform an oil pressure test. Refer to Oil Pressure Diagnosis and Testing .
2. Repair or replace, as required.

Loose and/or worn valve rocker arm attachments

1. Inspect the valve rocker arms and retaining bolts.
2. Repair or replace, as required.

Worn or damaged valve rocker arm

1. Inspect the rocker arm for wear or missing needle bearings
2. Replace the valve rocker arms, as required.

Bent or damaged valve push rod

Inspect the following components and replace, as required:

Inspect the top of the pistons for valve contact. If the top of the piston shows valve contact, replace the piston and pin assembly.

Improper lubrication to the valve rocker arms

Inspect the following components and repair or replace, as required:

Broken valve spring

Replace the valve spring and spring shim.

Worn or dirty valve lifters

Replace the valve lifters.

Stretched or broken timing chain and/or damaged sprocket teeth

Replace the timing chain and sprockets.

Worn engine camshaft lobes

1. Inspect the engine camshaft lobes.
2. Replace the camshaft and valve lifters, as required.

Worn valve guides or valve stems

Inspect the following components and repair, as required:

Stuck valves

Carbon on the valve stem or valve seat may cause the valve to stay open.

Inspect the following components and repair, as required: