one last question before 'go time'!

[perfecto951]

Ok, so the pump is being replaced. The gear was all chewed up and it was binding. Oil pressure problem solved.

However, before I start it up I want to ask if I need any seals on my OPRV. According to the exploded diagram I need 2 '999 707 145 40' part number o-rings to go on it.
OPRV Diagram

Now, I don't know if this is for the updated valve or for my old-style valve. currently there are no o-rings on the little piston, and it moves freely.

From what I'v been told the old-style valve doesn't need any seals - but I'm just double checking before I give it a go. With the car being driven only 180 miles in the last 14 months I just want to get it right.

[Granite 944]

Gear was all chewed up. Wow, I bet thats a rare thing.

As far as OPRV goes,

if you have the earliest of OPRV (commonly called the 3 pc one), and it looks like the pic below, then you don't need any O-rings.




If you have either one of the "later" style OPRV's (commonly known as 1 pc one, (and they really are more than one pc to them)), then you will need O-rings........two to be exact, and then you should know the difference between these two different, "1 pc" OPRV's. The 1pc replacement for the earlier 944 cars, and for up to and including all '86 cars is easily identifyable by the taper on the threads of it, and its shorter overall length (fig. A below). The latestest, and greatest OPRV will be fig. B (not for your car. Take note of the part number callouts for the O-rings, in the next picture, as they are different. I'm not sure where I got this chart from, but make sure of what your getting, as this would probably make some difference. Last pic is of a typical "1 pc OPRV, completely dismantled.

If you really do have the original 3 pc OPRV, clean it with solvent/scotchbrite (don't sandpaper it to death! your just increasing the clearance tolerance between the piston and sleeve if you do). Also clean the inside of bushing thats inside/mounted to the block that the piston slides into, and make sure its in there tight, and seated all the way.









I believe all the above to be true. Please someone correct me, If I'm wrong, or missing something here.

[perfecto951]

wow, thanks. thats the best and most complete reply I have EVER had on this forum. You guys rock.
Looks like some larger-than-sand-grain sized particles got in the pump. I'll take a picture of my bad oil pump and post it when i get a chance!