OPRV questions
 

hey guys, Im trying to find out a little more info on the different types of OPRV (oil pressure relief valves) I belive my 1987 924S has the older one peace kind. I just picked up a 951 oil cooler housing that came with (what I believe to be) A 3 peace oprv, but Im not sure if its complete, Its just a small piston and a spring and a screw on cap at the other end. Is this correct??? DOes anyone have pics of the differnt OPRVs?? The one in my 924S works fine but if the one for the 951 is better I will use it. Just tryin to figure out if its all there. Thanx guys, anyhelp would ROCK SmileWavy

This may help, sorry but I don't have a pic of the 3-piece style when I posted this on another forum. The difference in the two types of 1-piece OPRV's are the length and placement of the end O-ring. They have to match the housing style. The 86 951 is the only 951 that used the conversion 1-piece, 87+ were all the later style.

http://951forums.com/forums/index.php?topic=120.msg3378#new

So wait are you sating I wont be able to use my 87 924S oprv if I needed?? I thought they all work, doent matter the year. Tom I will post some pics of the 2 oprv's I have, Thanx for that info

You need to use the OPRV that matches your block year. In your case, the 87+ one peice OPRV. AFAIK, The covers are the same so you can use the 951 cover with the 87+ block and OPRV.

The OPRV's ARE NOT interchangable between early and late blocks. If your 924S has the late style 1-piece OPRV with the O-ring farther from the tip then you have to use that style OPRV with an 87+ cooler housing. If you bought a 951 oil cooler housing with a 3-piece OPRV then it's from an 86 you can't use your 924S OPRV in that housing either. I'm pretty sure if you are converting an 87 NA cooler to a 951 housing you need the 87 951 oil housing and OPRV. The detent at the bottom of the blocks are different between the 86 and 87 and that's why there are different length OPRV's. I'll try to find you a confirmed answer from info I have stored on another computer. Any pics you have of the OPRV you have would definitely help even if you just PM them. All I can tell you for sure is that the early 3-piece unit WILL NOT work in your 87 block.

Edit: Good news, it looks like you can still use your later 924S OPRV even in an early 951 oil cooler housing on the later blocks. The 86 and 87 951 oil cooler (thermostat housing) are the same part number which means just the OPRV is different due to changes in the block design. I'm still looking for that other info I have, bear with me!

COOl, thanx for the info. I gotta get to the garage and remove my oprv to take pictures. SO proly saterday. Im using a 1987 block and oprv in a 1986 951 oil cooler housing just to claer things up. Again thanx for all the help/info