Charlie

Some of you have read my post over the last couple weeks about no oil pressure. I received a lot of advice which I appreciated very much. The scenario was this. I bought a 944 with a bad engine, upon inspection the engine had metal from a balance shaft bearing that had melted. I cleaned and rebuilt the engine and when complete could not get any oil pressure. I had an estimate of repair for the previous owner, from a Porsche repair place stating the oil pump was bad. I did not think the pump was bad but could not get the pump to suck oil.
Will I finally figured out the problem. I looked at an oil flow diagram and noticed that the OPRV could effect the suction of oil from the pick up tube to the pump. Had just thought that it would effect the outlet side of the pressure. If it is open then it opens the outlet side to the inlet side. I had looked at my OPRV a couple of times and did not notice anything wrong. The piston moved up and down smoothly. I took it out again and looked more closely. Upon close inspection the piston did not quite cover the top of the 4 holes in the tube. The retaining ring inside the tube was stopping it from going any higher. I called Chuck at Paragon and asked him if he would look at a new one and tell me where the retaining ring was located and how high the piston went. He said the retaining ring was about even with the outside O-ring and the piston went up to the retaining ring. I removed my retaining ring and put it where it was suppose to be, about 1/8 " higher. This morning I put in the OPRV turned the engine over without plugs and after about 15 seconds I saw the oil pressure hand move for the first time, I had pressure.
How the retaining ring had moved down inside the tube I don't know, something freakish I guess and probably a first, but at least the problem is solved.

Again let me thank all the people with suggestions and advice.

osbekken

I have an Oil-pressure problem myself. Dont know whats causing it yet, but this is interesting reading...

I've taken out my OPRV and taken some pics:




The hole doesnt look this bad seen with the eye...
Considdering theese pics, could it be the OPRV causing my problems? The surface of the valve doenst feel as rough as it looks, and it apears to me like it moves smothly in and out. How do i check if it does go all the way in?

I have also checked the crankshaft bolt, it was a little to loose so i tightened it, but that didnt help...

Im open to sugestions and "what to do next" tips...

xsboost90

definitly have to have the crank bolt tight, or the oilpump wont work at all.

SoCal Driver

Good detective work. I'll add this to the data base for sure.

osbekken, I would spend the money and get the one piece replacement for your three piece design. You will be much better off in the long run.

Zero10

Hey, stupid question time!
Hope I don't lead to a thread hijacking here.
What year did porsche start putting in the 1 piece valve?
and if I ordered seals for my OPRV, and I got 3 parts for it (I think 2 o-rings and a washer?), are they for the 1 piece or 3 piece valve?
I have not gotten the parts yet, but I am getting ready to pull the OPRV out, along with the cooler housing, and I would just like to know (once I get it apart) if I have the right parts.
Sorry if I hijacked this thread, and Thanks in advance for any help.

Waterguy

Zero10:

The Figure B OPRV was installed starting in early 1987 model year. The Figure A OPRV is the one-piece retrofit for 1986 and older cars. I don't know why there would be two o-rings, unless they supplied a kit that would work for either one piece unit; maybe the part numbers on the picture will help.

SoCal Driver

Started using one piece OPRV's in the mid 86 model year.

Tom M'Guinn

Hey, I called that in the original thread! Do I get a prize? Seriously, thanks for posting the resolution. So many times, we hear the problem, but never hear the cure.