Common causes of Low oil pressure and High oil pressure

HomeBlogCommon causes of Low oil pressure and High oil pressure
Posted on 2 December 2015

Always refer to the manufacture specifications for oil relief pressures

Causes of Low Oil Pressure

Low oil level
Oil not flowing into the pump at start-up
Pump runs too slow to deliver sufficient oil
Oil too hot, viscosity too low.
Incorrect oil Viscosity
Worn oil pump
Worn crankshaft bearings
Fuel in oil reduces viscosity oil fuel dilution
Oil change is required
Oil relief valve stuck open, worn or broken spring
Oil gallery plug missing , removed or damaged
Oil gallery oring or seal damaged leaking internally
Oil gauge faulty
Damaged /cracked oil pick up pipe
Oil pickup screen blocked or partially blocked
Oil sludge in the bottom of the sump
Leakage between oil pump and cylinder block or housing
Incorrect crankshaft bearings fitted after rebuild
Low engine idle speed

Causes of High Pressure

Pressure remains high after cold start. Oil flows adequately into the pump, but does not flow through the oil galleries
Oil is thickened by soot load
Oil is thickened by oxidation
Oil viscosity is too high. Oil flow is poor.
Filter blocked or partially blocked.
Deposits in oil gallery system cause increased back pressure.
Oil too cold high viscosity
Oil relief valve stuck closed
Oil gauge faulty
Blocked oil passage
Bearings fitted incorrectly after rebuild
Incorrect bearing fitted after rebuild