ahofam123

This morning was the second time I was able to cold start my car after replacing the oil pickup tube seal and wetsanding the oprv. The first time it took the car 5 sec. to build oil pressure and this morning it took only 2 sec to build oil pressure. Although not perfect, it is a lot faster than the 30 sec it took prior to these repairs. I have driven other cars where the oil pressure registered instantly and some cars where it took 1 to 2 sec, to build oil pressure. How long does it take you guys to register oil pressure on a cold start?

Sami951

What sort of oil filter are you using? I'm pretty sure I used to have instant oil pressure, but now I'm getting 1-2 sec delay... I'm blaming the cheap filter I put in there, my guess is that the drainback flap has failed on it.

ahofam123

I am using a mahle. I was previously using a purolator that looks identical to the mahle and was getting tht same results.

Kevin Baker

ahofam, after I replaced the o-ring, the pressure builds UNDER one second. It's ALMOST instant.

Try to find a one piece oprv in a salvage yard or find someone who has a blown motor. IIRC you'll have to remove the sleve inside the oprv cylinder to upgrade to the one piece.

Kevin Baker

Sorry, I wasn't done.

When you start the car the oil pump pressurizes the cylinder (oprv) once it is "filled" the piston will move to change the route of the oil flow. If there is "extra" room in the oprv cylinder, the pressure will take some time to build before the piston moves. That is verifyed by my delay without the o-ring, and the lack of delay with the o-ring. The piston in the oprv has a hole at the tip, and it should move easily.

ahofam123

Thanks Kevin. If it takes another 2 sec. next time I start it, then I guess that I'll start my search for the updated 1 piece valve.

triscadek

When did the 1 piece valve start being used?

Kevin Baker

IIRC 1986.

pikey7

Almost! '87 cars had a new valve with different dimensions to the earlier cars. There is a late 'style' update available though for the early cars.

944ZEN

My oil pressure is up in 1-2 sec. cold as well. If i look at the needle, the build up is smoth with time, eg. no sudden jumps to about 4.5. at idle.

Hot it's up more instantly but not so high, around 2 on idle.

BTW. I'm running 5-40W full synt.

I tried to change oiil filter from MANN to original Porsche, and i didn't help anything.

My problems has been solved for 6 weeks now. The car is now the same as when i got it in feb. 2003.

PS: 1 have the old 3-piece, Piston/spring/nut OPRV.