Voith

I was looking at some OPRV threads today, and found out that my oprv is different than both early and late..

Is this third option or this some other valve I confused with OPRV?

rocooper45

Sorry for my ignorance. What is the OPR valve?

Voith

Oil Pressure Relief Valve

The idea is that oil does not exceed certain pressure, since pump is RPM dependent..

jmj951

Has the appearance of a custom-made one-off.

nofalls

How does it thread into the oil filter housing? Is there another threaded piece that goes in over it?

Scott H

That's what I was thinking. I guess someone didn't want to pay the $$$ for a new one from Porsche.

Voith

As far as I remember there is, but I don't find it at the moment.. I took the engine apart few years ago and yesterday I was arranging all back together and I foud this protected in styrofoam.. If I remember correctly I put the oprv in styrofoam, so this should be it..

It definitely came off my 951.

jmj951

It just slides inside a single cylinder (as long as the housing is properly aligned) that's a combination of three pieces together: the housing, a cylindrical connector with o-rings on each end that sits between the housing and the block, and the block. Almost impossible to explain in words now that I read this. Just look for some pics on this to understand.

There is a very short threaded bolt (more like a cap) on the housing that covers the hole/cylinder containing the OPRV - the OPRV pushes against this cap. In my car, I have the 3-piece OPRV with a spring that simply provides the force within the OPRV in the cylinder. The OPRV in the pic above is a copy of a newer version, and I don't know exactly how that works.

alex_cristocea

I think it's the OPRV from the cylinder head ( p/n 944 107 239 01).

jmj951

Why have I never heard of this before...must not be common to remove/replace this. Is this part also on the 86 head?

Voith

alex I think you nailed it. Thanks!

I must have packed the oil housing oprv somewhere else..

lart951

Yes, some simple measuring will confirm is the pressure valve on the head, I believe the picture made it appear larger than it is.

reno808

good find.
I was stumped