low oil pressure problems

[s-burrus]

low oil pressure at and idle when reved up pressure riases to 30psi and drops down to 10psi while its still reved . doesnt seem to be anything wrong with oil pump. lifters rattle replaced 3 bad ones and still ahveing problems timing chain rattles already replaced guides tensioner chain and pullies any ideas as to what could cause these problems ? 1989 240sx 2.4

[maryjane]

how many miles? weight of oil your using? sounds like your motor is worn out

[tyrodtom]

The chain tensoner uses oil pressure to keep the chain tight, if it leaks some of your pessure off your chain will be slack plus no or little oil will get to the head.

[josho]

Usually low oil pressure means worn rod/main bearings. Time for a swap.

[tyrodtom]

You would've had to take off the front cover to replace those parts. If either one of the 2 o-rings to and from the oil pump in the front cover is bad, you lose most of your oil pressure, also the same thing happens is the gasket on the oil tensioner fails.I'd check those out first.

[s-burrus]

we pulled the timing chain cover off and turns out the owner of the car used silicone for every gasket on the car when he rebiult it to save money via not buying the gasket sets . is there suposed to be a gasket on the oil chain tensioner? cause it wasnt even siliconed in and i have a feeling that might be part of the problem as well as the tension just being completly wore out and was actually falling apart even though the owner told us it was brand new ... im just glad this is his pile of crap and not mine he would be better off swapping everything back over into the standard he has sitting in his yard and starting over with that since the whole car is indeed wore out and in need of a ground up rebuild.

[tyrodtom]

Those 2 0-rings i'm talking about on the front cover were metal, brass I think, and yes there was a paper gasket on the tensioner.Sounds like several reasons for low pressure.

[s-burrus]

yea i got the 2 orings for the timing cover as well as a new orings for the pickuptube hopefully the paper gasket will do the trick ill have to call the nissan dealer to track it down thx for all ur help ill be sure to put up another post if it works for other people who may have the same problem in the future