Oprv

hosmerb · 10-17-2014, 04:50 AM

I'm rebuilding an OPRV on a car that hasn't been started in a long time. I ordered the O-rings today but would like to keep moving on my assessment of the vehicle. Basically, I want to try and start it this weekend but I wont have the O-rings. Can I install the valve without the O-rings and start the car without breaking anything?

Thanks,

Hosmer

944 Ecology · 10-17-2014, 05:40 AM

Without the O rings, you will not build up any oil pressure. Do that for a long enough time (e.g. five seconds), and you will get to rebuild your engine.

CHICKS · 10-17-2014, 09:17 AM

Don't do it.

Pauld_94S2 · 10-17-2014, 06:14 PM

Can you put the OPRV back in with the original O rings, or are they trashed?

hosmerb · 10-17-2014, 08:23 PM

The old ones are nuked. I couldn't get the valve out of the block at first. The oil cooler O-rings went bad and the car was parked... for five years. I got the car for free and I have a $500 sunk cost budget before I part it out so I'm just trying to see if I can get the thing to start. I'll wait for the O-rings though, just in case I get lucky and the engines still good.

Interesting car to work on. I replaced the oil cooler O-rings last weekend and not one broken or stripped nut or bolt. I don't know why but I find the unusual...

Thanks for the advice,

Hosmer

Volhv · Volhv's Garage

Quote:

Originally Posted by hosmerb

not one broken or stripped nut or bolt. I don't know why but I find the unusual...

It's a German thing. I've had a bunch of Japanese cars, and the quality of the metal they use is pretty poor. Everything breaks!
But don't speak too soon, the tiny M6 waterpump studs will come out in pieces.... unless you leave them be.

djnolan · djnolan's Garage

Are you talking about the one piece OPRV? I have never seen one so I can't comment.

But I can tell you the three piece OPRV does not use O-rings. O-rings are only used on the oil cooler pipes on the 3-piece OPRV setup.

At least this is the way mine went back together on an 85.5 model year.

If you try to use O-rings on the three piece OPRV no telling what might happen. The plunger might get stuck in the bore.

Do make sure to use an OPRV alignment tool, too.

hosmerb · 10-30-2014, 05:37 PM

Nertz... now I'm completely stumped, and stuck. I put a green and a black o-ring on and now the thing is stuck again. I hope I don't have to remove the casing to get it out. I used the alignment tool and it moved freely. I think I have an o-ring problem and will have to do more research. Looks like I have a bevy of write-ups on the subject so that's good.

I will say the dam thing is confusing. There's supposed to be two valves, I know mine does not look like the one above but its in no way one piece. Its not three pieces either, its four. The nut, a spring, a plunger and a tube the plunger slides in.

sausagehacker · sausagehacker's Garage

If you need a good OPRV, I have a few. One is an early 3-piece (17mm) and one is a 1988 late retrofit valve that opens and closes smoothly (24mm).

hosmerb · 10-30-2014, 06:47 PM

It looks like I have version #3 of the valves pictured in a '86 - 944 non turbo, std shift. Is that OK? From what I've read, that valve is for an '87 on.

Thanks for the help on this...

p.s. I obviously picked the photos from this write-up (944 Foot To The Floor: How to remove and replace OPRV (Oil Pressure Relief Valve) on a Porsche 944) hope that's okay...

kdjones2000 · kdjones2000's Garage

#1 is the original OPVR (3 piece) for all cars up to (I think) 87.

#2 is the retrofit OPVR (1 piece) for those same cars as in #1

#3 is the OEM OPVR (1 piece) for 87+ cars.

If you have an '86 block (Look at the 44.xx number stamped on it), then you need a #2. The #1 is a matched set for the plunger and the piece in the block.

hosmerb · 10-31-2014, 05:20 AM

I found this near the oil fill, close to the firewall. I think its on the engine and not the bell housing. To me, it looks like M44 707 and 43H0834... So that's an '86 right? If so, I have the wrong valve...

944 Ecology · 10-31-2014, 05:23 AM

Quote:

Originally Posted by hosmerb

I found this near the oil fill, close to the firewall. I think its on the engine and not the bell housing. To me, it looks like M44 707 and 43H0834... So that's an '86 right? If so, I have the wrong valve...

Nope, H is for model year 87.

hosmerb · 10-31-2014, 06:06 AM

So engine swap at some point then because date of manufacturer is 10/85 and vin says 1986... I have the right valve but purchased the wrong O-rings which explains why the thing is stuck. Live and learn I guess.