Jeff N.

OK - all done. A few lessons learned from the job.

- Tom's instructions are great.

- When I re-installed the OPRV in the aligned housing, it just slipped right in and started. No pressure required. When it was unaligned, it took some pressure to the threads to start. I assumed this was normal as the unit has a spring in it but it's apparently not.

- A 32mm bicycle headset wrench works wonders to help get the oil lines off. I wasn't able to remove the rear one at the housing in the car so I undid it at the cooler side. You can pull the housing with the aft oil line attached and remove on the bench. I then reinstalled it started but loose and lined the angle up and tightened it in the car.

- I rechecked the alignment of the housing after reefing on the oil lines when installing. There's not much torque holding the housing in place, it seems it could slip some while tightening up the oil lines (mine didn't).

- That 3 piece heatshield is quite the trick to assemble alone. Bring a friend.

- This has to be one of the nastiest, messiest, tightest jobs I have ever done. Nothing like working on your head in a mix of oozing oil and antifreeze. I think just about every bolt or nut needed me to use a universal. And I had a flex head snapon quarter inch ratchet as well.

Glad it's done. I hope I won't be doing this any time again soon.

zerMATT951

Reviving this thread... Got a question. I'll be reinstalling my OPRV & housing this weekend and based on what I've read, I should ditch the 3-piece and upgrade to 1-piece. My concern is whether or not a late-style 1-piece will work in my engine. Are there internal differences that would prevent me from swapping an 88/89 1-piece in?

Also, I did rebuilt the oil/water heat exchanger (aka oil cooler) on my 924S several years ago. It had the 1-piece and I did the job successfully without the alignment tool. Did I just get lucky taking my time while tightening everything up with the OPRV in place? Do I really need the alignment tool to put turbo housing back together?

PorscheDoc

Correct, the late style will not work in your block. You will need the updated 86 1 piece OPRV. There are two 1 piece units, an early unit and a late unit. And you can use the 1 piece OPRV as the alignment tool.

zerMATT951

Perfect, thanks for the clarification!

Now I need to locate an early-model 1-piece OPRV for this weekend .

Jeff N.

Put a WTB post on the board - you can usually find someone with one for sale. That's what I did.

zerMATT951

Does anyone have a picture of the 1-piece valve for an 86? Lart is going to check his inventory but we don't know what the older style looks like. Too bad I can't use an 88 valve, he's got one on eBay right now...

Jeff N.

See post 14 on this thread for a picture of an 86. The later model is a little different - the tip and threads are a bit different. If you search the archives, you'll find some comparison pictures.

zerMATT951

Ok, so here's early (left) beside late (right)... it looks like the big difference is those ground off threads on the early version, but there are a few tapers on the late version that aren't there on the early, and the grooves look slightly different. If the threads were the only difference, I've got a really nice grinder that could make quick work of that .

zerMATT951

Looks like the old 3-piece will be going back in this weekend. Reading Clarks Garage, he says that the 3-piece isn't as finicky as the 1-piece with alignment, and mine was working when it came out, so what the heck.

I'll still keep my eye out for a used early 1-piece to have as a spare if my oil pressure starts to act funky.

One more question; should I go ahead and replace the oil thermostat while I'm in there?

Jeff N.

I think the tips are not the same as well.

Re the thermostat - why change unless something's wrong? If you tracking it, you can check to see what the temp is of the thermostat installed in the car. There are two versions - it's stamped on the body in celsius unit. Archives will tell you the exact temps - I think 95 and 105 but not positive.

ajdre11

Barry-still have one of the OPRV’s available for sale? 944 107 035 11
thanks-Andre

Bikendrum

HI Everyone, I'm pretty new with the 944 these cars are so much more difficult than the Miatas I've been racing. but they look beautiful! My questions is the OPRV old style 3 pc.

My car was fine just a tiny leak underneath. yesterday I pulled it out of the garage, heard a pressure liquid sound and saw my oil all over the drive. My Mahle oil filter seal blew out.
I pulled the oprv, (old 3 pc). do you think that is the cause or if I clean it up should it work well? I've read most of the posts on here and its all over the board. I need to get the car running
but I will order anew oprv Monday.
thanks !!

if anyone has a 86 new 1 pc they want to sell let me kno!

wildcat077

Don't mess with a faulty OPRV ... i've had two oil fires with my race car where the seal blew out on the oil filter and onto the header !
I ended up purchasing a brand new unit from the dealer , it's cheaper than burning down your car.