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Upper Engine Noise, Regardless of Engine Speed

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Upper Engine Noise, Regardless of Engine Speed

Cause Correction
Low oil pressure
Worn or damaged valve rocker arm
  • Inspect the rocker arm for wear or missing needle bearings
  • Replace the valve rocker arms as required.
Improper lubrication to the valve rocker arms Inspect the following components, and repair or replace as required:
  • The valve rocker arm
  • The valve lash adjusters
  • The oil filter bypass valve
  • The oil transfer tube
  • The oil pump and pump screen
  • The engine block oil galleries
Broken valve spring Replace the valve spring.
Worn or dirty valve lash adjusters Replace the valve lash adjusters.
Stretched or broken timing chain and/or damaged sprocket teeth Replace the timing chain and sprockets.
Worn engine camshaft lobes
  • Inspect the engine camshaft lobes.
  • Replace the camshaft, valve lash adjusters, and rocker arms as required.
Worn valve guides or valve stems Inspect the following components, and repair as required:
  • The valves
  • The valve guides
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:
  • The valves
  • The valve guides
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