no oil pressure on startup

[Rog]

Hi

I have an 04 d22 zd30. Whenever it sits for more than 1/2 and hour, the oil light takes ages (as in more than 10 seconds) to go out. I got and oil pressure gauage put on and there is no oil pressure initially.

I took the oil filter off after it had been sitting and there was no oil in it.. so the oil is draining back.

As the oil pressure comes up, a "buzzing" starts at the font of the motor. This buzzing gets less as it gets hot, but doesn't completely disappear. The oil pressure I think is a bit low once it is warm- Ok at idle (probably 15psi), but doesn't get about 30psi when hot with no load and sits on about 20psi on the free way.

Any thoughts?

Thanks

 

[jonney]

you could try an engine flush to get rid of all old engine oil deposits then re fill with correct weight engine oil plus use a new genuine oil filter. also remove the oil pressure sender unit on engine and soak the threaded end with small hole it in some diesel fuel over night , could be abit blocked. actually try that first before engine flush etc.

 

[Rog]

Thanks jonney

Its a new sender so it shouldn't be that.

The mechanic was supposed to have flushed it.. perhaps I should give it a go myself.

Do these motors have an an anti flow back valve.. there isn't one in the oil filter-it's just a straight cartridge.

Thanks

 

[jonney]

not sure about your model engine etc but i know the Pajero,s have whats called an Oil Pressure Release Valve and when these play up you do lose alot of oil pressure. just hope its not your Oil Pump .

 

[markgiles]

Hate to be that guy that reopens old threads - but this is literally the only post I can find with the same symptoms as mine.

Did you ever fix this?

Mines a zd30di from a GU Patrol.
And in mine the buzzing occurs as the oil pressure comes up on the gauge.