lee101315

Consistently these past three mornings, on each start up the oil light will come on (and read 0 oil pressure) for about 30 secs, and then everything will go back to normal.

I know there is nothing wrong with the gauge because I hear the lifters making noise until the gauge indicates that I have oil pressure. When it comes up to normal, the gauge indicates between 4 and 5 bar cold, and then it comes down to 2.5-3 bar warm (which is healthy).

I did reach under the car last night to make sure the 24mm bolt on the crank was tight... I was kinda hoping to find it loose.

Any ideas on what I should do? Should I check the oil pressure relief valve? I can only work on my car on Sunday, since the rest of my week is busy.
I'd appreciate any input, thanks.

dillon410021

mine does it for about 2 seconds

bigdeano

Could just need a new oil filter. When was your last oil change?

Spidey944

My 86 was doing that, ended up removing the OPRV, replacing it with one I picked up as part of another purchase, and the problem was solved.

When I would shut the car off after a short drive, it would hold pressure for about 6 hours, but if I shut it off after a long drive where the OPRV would open completely, I could go out and start it an hour later, and the pressure would already have leaked down, and would take 15 secs or so to build pressure again.

lee101315

I changed the oil last week

bigdeano

Next step would be to definitely check the OPRV.

Jeremy Himsel

Did it do that before the oil change? What filter did you use? 30 seconds is still a long time even if the anti drain back valve in the filter isn't working. I'd start by changing the filter and chek the OPRV operation. It may have some sludge on it and be sticking a bit when cold. Pull it out and clean it up real good.

TRP951

damn 30 seconds if my car didnt have oil pressure in like 2-3 seconds I would shut it down

2bridges

30 is WAY to long.

4-5 seconds to build after sitting for a long period (winter months for example)

Something is gong on. Agree with Himsel for starters, may have a filter with a defective valve, or wrong filter. Start there.

lee101315

Yea, seeing that red light on for more than a second bothers me. This morning, it took almost 30 secs to get oil pressure. I was reaching for the ignition, ready to shut it down and to tow it into work, when it finally built up pressure...

Saturday afternoon was dead here in the shop (for once!), so I grabbed my car and threw it up on the lift.

I tried swapping the oil filter for an original one, no dice.

I then removed the oil filter again, and fed motor oil through a funnel through the orifice (hoping to saturate the pump). Reinstall filter, start the engine,and I have oil pressure immediately

After checking the price of a new Oil pressure relief valve, $250.00... OUCH!
I removed the OPR, and the piston wouldnt come out easy. I cleaned the valve, spring, and the passage. I also installed a 1.5mm washer behind the spring, hoping to add some oil pressure. Everything is ok now, thanks for your help guys.

I noticed that the new OPRs are one piece, has anyone installed one of those?

lee101315

Damn, it happened again. I cleaned it once again, installed it , and it was okay for another week.

I just went out and bought the one piece OPR valve... at $250 it hurt!

Tom M'Guinn

You did the right thing. The oil thermostat housing may have come out of alignment, causing the 3-piece unit to hang up, but the retro one-piece is the way to go either way.

Ski

If does it again, you might want to consider getting the alignment tool for the OPRV also. good luck.

lee101315

An alignment tool? I dont have one of those... do you think its possible to improperly install the one piece OPR valve?

Spidey944

With the one pieve OPRV you can loosen the housing bolts, install the OPRV using it as a centering pin, then retighten the housing bolts. Works great.