Low Oil Pressure or Fluctuating

(Oil Light may be On or Flashing)

Improper viscosity engine oil.

Replace engine oil with correct viscosity.

Faulty gauge.

Verify oil pressure and check sending unit and gauge. (Refer to "Oil Pressure Check" in this section.)

High ambient temperature.

Check cooling system and verify correct engine oil viscosity.

Contaminated engine oil.

Verify engine oil is diluted with gasoline, coolant, etc.

Frozen water in oil pan.

Thaw water and change oil.

Cracked oil pickup tube and/or gallery plug.

Verify oil pickup tube is not cracked and all seals/plugs are not damaged and installed.

Faulty regulator valve.

Replace valve.

Faulty oil pump.

Replace oil pump.

Engine running clearances excessive.

Refer to the Basic Engine section and check bearing clearances.

Crankcase over/under filled.

Verify oil level and quantity in crankcase.

High Oil Pressure

Improper viscosity.

Replace engine oil with correct viscosity.

Faulty oil pressure gauge.

Verify oil pressure and check sending unit and gauge.

Plugged oil filter.

Replace oil filter.

Ambient temperatures to low.

Verify correct viscosity engine oil.

Faulty regulator valve.

Replace valve.

Oil Light On or Flashing

Low oil.

Add oil.

Coolant in Oil

Cylinder head plug or gasket.

Cylinder head/block casting porosity.

Inspect cylinder head plug.

Replace appropriate casting.