I have an ea71 that has about 55 pounds of oil pressure when engine is first started. As the engine warms up the oil pressure slowly drops and after I have drive it for say 10 minutes or so at idle the oil pressure drops to zero pressure. When I increase engine rpm the pressure builds again. Can someone please point me in the right direction as far as what to check first? Thanks for the help......Pete

The gauge.Stock are notorously low reading at low pressure.

Try a mechanical one for a test.

Probably a combination of worn bearings and oil pump. I take it the oil is in good shape, not gassy smelling. The oil pumps can be had relatively cheap and are easy to change if other things look good.

 

Mark

The gauge.Stock are notorously low reading at low pressure.

Try a mechanical one for a test.

 

Sorry forgot to mention I did install an analog pressure gauge. I feel good that it is accurate

Probably a combination of worn bearings and oil pump. I take it the oil is in good shape, not gassy smelling. The oil pumps can be had relatively cheap and are easy to change if other things look good.

 

Mark

 

If the oil pump was bad/weak would it still give me good oil pressure?

Its common to have these engines run low oil pressure at idle after warmup. Try a thicker oil if you live in a hot place. You might even get away with running some Delo 15W40 if you live down south.