Mello

Porsche PET shows 2 identical o-rings(1 at the end, and 1 in the middle before the threads) and 1 metal ring, so 3 in total. However every picture of an oprv everywhere else shows 1 o-ring and 1 metal ring. I just pulled out my OPRV and there was only 1 o-ring and 1 metal ring. So which is it? Ian at 944online sent me 2 identical o-rings and 1 metal ring, which matches the Porsche PET. There is a groove in the middle of the OPRV where an o-ring could go, although slightly larger in diameter than the other groove where an o-ring definitely goes. This is a late model OPRV for an S2. I'm gonna put all three rings on, unless someone here tells me otherwise. Thanks!

KuHL 951

The 2nd o-ring goes between the smaller diameter lower section (with the piston) and the hex head cap section. You can only replace it if you disassemble the cap from the lower section. Many people have found when they break it down it to get to that inner o-ring it never works right again. Try the bottom o-ring only and see if it works first. If it doesn't work you need the inner o-ring or a new OPRV. That part is a terrible design; how many other cars have you heard of that have chronic OPRV problems?

joonas

John_AZ

Never had a problem after replacing the 2 "O" rings.

Clean carefully and do not mix up or reverse parts--Keep in exact order.
The inner pistons & spring part--# 2, 3 & 4 come out----keep in exact order---clean.

Mello

Thanks guys!
Today I pulled the OPRV apart. The inner o-ring was or got torn up from pulling it apart. I put the second o-ring on and popped it back together. I noticed that now the screw end and the housing now have some spring loaded movement of about a quarter inch in and out of each other. I didn't notice that before.
The piston inside the bore seems to move freely as well.
I did all this because I was getting the "wookie" sound which is notorious from OPRVs on S2s. I think that sound is gone now.
I also had/have kinda high oil pressure according to the dash gauge, but changing the o-rings on the OPRV didn't help that. The lowest my oil gauge goes is between 3 and 4 at idle when hot. I am running 15w-50 Mobil 1 which is kinda thick. I'm gonna try something thinner next and see if anything changes.
Just to document for others in the future.... The OPRV was easily accessible on my S2 with the batwing/belly pan removed. I used a 24mm socket and about a 12" extension from beneath with the car jacked up on one side. The OPRV broke loose easily and screwed in and out with almost no resistance or binding. Torque is 33 foot pounds.