Pressure Reducing Valve, What can you tell me?
10-04-2011 | 10:38 PM
#16
Racer
Joined: Oct 2009
Posts: 486
Likes: 15
Hi
I know this is a very old thread but i am changing the o-rings on my pressure relief (reducing) valve and i got the o-rings as per the sizes listed (2-013, 2-014) but the o-rings I got had rounded edges and they protruded a little out of the grooves and the valve doesn't go in as far as it does without the o-rings. Has anyone else had this problem?
Here are two photos of the valve installed, one with the o-rings and one without.
I know this is a very old thread but i am changing the o-rings on my pressure relief (reducing) valve and i got the o-rings as per the sizes listed (2-013, 2-014) but the o-rings I got had rounded edges and they protruded a little out of the grooves and the valve doesn't go in as far as it does without the o-rings. Has anyone else had this problem?
Here are two photos of the valve installed, one with the o-rings and one without.
Jay W
I read your post some time ago. That was what got me thinking about this so thanks you did me a favor. I searched for the post but could not find it. My lifters have not been loud all this time but they have been noisier than they should be.
I think my problem was the PO tightend the set screw too much and deformed the body. The valve is not operating smoothly, it sticks up and down. I have cleaned it with alcohol and LPS and it has freed up a bit but I am going to replace it.
I also got new O'Rings for it. They are not listed in the PET. The correct sizes and anybody reading this later can order them with the Parker o'ring numbers: 2-013 and 2-014. Get them in Viton and you should be good.
Finally, Volume 1A-Engine of the FSM on page 17-102 calls it the "Pressure Reducing Valve". Vol 1A is for the 16v engines. PET in illustration 103-4 calls it "Pressure Relief Valve" (944 107 139 00). So there we go, it is not OPRV though!
To solve any further debate here is a picture:Sorry, Rennlist is not letting me log on!
I read your post some time ago. That was what got me thinking about this so thanks you did me a favor. I searched for the post but could not find it. My lifters have not been loud all this time but they have been noisier than they should be.
I think my problem was the PO tightend the set screw too much and deformed the body. The valve is not operating smoothly, it sticks up and down. I have cleaned it with alcohol and LPS and it has freed up a bit but I am going to replace it.
I also got new O'Rings for it. They are not listed in the PET. The correct sizes and anybody reading this later can order them with the Parker o'ring numbers: 2-013 and 2-014. Get them in Viton and you should be good.
Finally, Volume 1A-Engine of the FSM on page 17-102 calls it the "Pressure Reducing Valve". Vol 1A is for the 16v engines. PET in illustration 103-4 calls it "Pressure Relief Valve" (944 107 139 00). So there we go, it is not OPRV though!
To solve any further debate here is a picture:Sorry, Rennlist is not letting me log on!
10-05-2011 | 03:36 AM
#18
Thread Starter
Burning Brakes
Joined: Nov 2003
Posts: 1,208
Likes: 0
From: Bay Area, California
Blast from the Past!!
My recollection of replacing this valve was that I was concerned because it was so hard to press it into place. Make sure you put some oil on on the rings and watch as you push the o-ring into the head. Make sure it does not pinch and shred the o-ring. You must push it in far enough for the pointed set screw to engage the the V cut that circles the valve. You could measure this distance by putting the setscrew in place with the nipple exposed in the oil passage, measure the distance from the nipple to the top of the hole, and measure the same distance on the valve body and you have how far you have to push it in. Make sure you don't drop whatever you use to measure with into oil passage!!!
As I recall you are compressing both o-rings as you push it in the final few millimeters. It requires quite a bit of force to push it in. If you are doing it correctly everything will be fine as the head is milled to compress the o-rings as you push it in.
Looking at your pictures the valve needs to go in as far as in the top picture. As I recall that groove in the valve should be equal with the head. Good luck, I hope this helps. Push it in, just like your gf she will like it
As I recall you are compressing both o-rings as you push it in the final few millimeters. It requires quite a bit of force to push it in. If you are doing it correctly everything will be fine as the head is milled to compress the o-rings as you push it in.
Looking at your pictures the valve needs to go in as far as in the top picture. As I recall that groove in the valve should be equal with the head. Good luck, I hope this helps. Push it in, just like your gf she will like it
11-04-2013 | 01:54 AM
#20
Burning Brakes
Joined: Mar 2004
Posts: 1,151
Likes: 0
From: Calif
MEK will work better than alcohol.
lubricate the O-rings first, and make sure there are no burrs in the housing or the bore. Look to see if the valve could be hanging up on something.
what are you using to press it into place?
lubricate the O-rings first, and make sure there are no burrs in the housing or the bore. Look to see if the valve could be hanging up on something.
what are you using to press it into place?
09-30-2015 | 12:54 AM
#24
Rennlist Member
Joined: Apr 2011
Posts: 3,444
Likes: 154
From: Elizabethton,TN
I think that this is all for the 85/2 cars and beyond. the early ones had a PRV pressed into the head. It says in the WSM that these are to removed and a later one installed after drilling the head. I just cleaned mine up, checked it for movement, and let it alone. Guess I'll find out when I fire it up. thanks.
Last edited by Tiger03447; 09-30-2015 at 12:56 AM. Reason: misspelled word
09-30-2015 | 04:04 PM
#25
5th Gear
Joined: Oct 2009
Posts: 5
Likes: 0
It is very easy to remove with the head on the car. There is a small allen screw towards the back of the cylinder head just above one of the manifolds. You need to remove the coolant tube that runs near the headers. Just take off the two bolts that hold it to the head and it will give you enough room to get an allen socket on there. If it is the later model you will not need to drill out the valve, you just remove that screw, put a flat head screwdriver under the valve and it will pop out. Use the referenced parker o ring numbers to get the proper o rings, and install.
It is really hard to get back in due to the o rings, so I put an extension on it and gave it a tap and it popped right in.
The seals are old and brittle, so it is likely that you are losing pressure, I'm sure I was. You can see all the crap that built up around the little stop groove, which means it certainly was not sealing properly.
It is really hard to get back in due to the o rings, so I put an extension on it and gave it a tap and it popped right in.
The seals are old and brittle, so it is likely that you are losing pressure, I'm sure I was. You can see all the crap that built up around the little stop groove, which means it certainly was not sealing properly.
10-02-2015 | 05:10 PM
#27
AutoX
Joined: Jan 2011
Posts: 12
Likes: 0
10-02-2015 | 07:45 PM
#28
Rennlist Member
Joined: Apr 2011
Posts: 3,444
Likes: 154
From: Elizabethton,TN
Dear AlfaDoc Would you happen to have the tech bulletin on this subject for the Early cars too? If so, pls PM me with the link or post it so everyone can see. Need p/n's in case there are two different PRV's.
thanks
thanks
06-22-2017 | 04:27 PM
#30
Racer
Joined: Dec 2015
Posts: 271
Likes: 15
From: In the middle of Ohio