Oil pressure relief valve question
05-07-2003, 02:26 PM
#17
Addict
Lifetime Rennlist
Member
Lifetime Rennlist
Member
Thread Starter
Join Date: Nov 2001
Location: Dayton, Ohio
Posts: 7,262
Likes: 0
Received 0 Likes
on
0 Posts
</font><blockquote><font size="1" face="Verdana,Tahoma,Helvetica">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Helvetica">Originally posted by Perry 951:
<strong>Yea.. probably got the newer style tool. It is about 1mm thicker.</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Helvetica">That would be the problem. 1mm is about right. I borrowed the tool from Tifo. Not his fault, that's what I get for being a cheapskate!
New tool is on the way, this should be a pretty simple fix.
Thanks Brian!!!! See ya at the Taj thing.
<strong>Yea.. probably got the newer style tool. It is about 1mm thicker.</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Helvetica">That would be the problem. 1mm is about right. I borrowed the tool from Tifo. Not his fault, that's what I get for being a cheapskate!
New tool is on the way, this should be a pretty simple fix.
Thanks Brian!!!! See ya at the Taj thing.
05-07-2003, 04:40 PM
#18
Addict
Rennlist
Site Sponsor
Rennlist
Site Sponsor
Ahem-I haven't had a problem with the "tool" being too tight, er-maybe that's just me.
Sounds like you've got it figured out Pete. I wouldn't take the whole thing apart unless you just can't get it to work with the new alignment tool. I think you'll be okay by just loosening the cooler bolts and working it around.
Good luck with it!
Sounds like you've got it figured out Pete. I wouldn't take the whole thing apart unless you just can't get it to work with the new alignment tool. I think you'll be okay by just loosening the cooler bolts and working it around.
Good luck with it!
05-07-2003, 04:51 PM
#19
Addict
Lifetime Rennlist
Member
Lifetime Rennlist
Member
Thread Starter
Join Date: Nov 2001
Location: Dayton, Ohio
Posts: 7,262
Likes: 0
Received 0 Likes
on
0 Posts
I should be able to get it straightened out without taking the housing off. If I have to take it apart, at least I won't have to worry about it anymore. Thanks again for the help guys.
05-07-2003, 05:58 PM
#20
Burning Brakes
Join Date: Jul 2002
Location: Northern Virginia
Posts: 761
Likes: 0
Received 0 Likes
on
0 Posts
the oil press. relief valve is not causing your higher than normal idle oil pressure readings. The valve is designed to open and relieve pressure when the oil is cold and thick and the engine is revved. It will only open when oil pressure reaches a predetermined point, when the engine is idling the valve is supposed to be closed. If your problem was no, or low oil pressure then the valve might be at fault, or it might be misaligned. You either have the wrong sending unit or the one you took off was sending an incorrect signal.
05-08-2003, 08:09 AM
#21
Race Director
The OPRV responses to oil-pressure only. It has no idea what RPM or temperature the oil's at.
The issue with the early valve is that the spring will be crooked if the housing isn't prefectly centered over the bore. Then as the plunger slides out and compresses the spring, it binds on the inner side and doesn't let the plunger fully retract. This drops oil-pressure down to only 4 bar instead of 3.
This misalignment is easily pinpointed if he gets the updated one-piece OPRV for early blocks (slightly smaller than 1-piece on '87+ cars). You'll find that you can insert the valve, but due to the slight misalignment, you won't be able to screw the threads in.
Pete's high and stuck oil-pressure will go away when he aligns his housing (Porsche could've and should've solved this problem with some locating dowel pins).
The issue with the early valve is that the spring will be crooked if the housing isn't prefectly centered over the bore. Then as the plunger slides out and compresses the spring, it binds on the inner side and doesn't let the plunger fully retract. This drops oil-pressure down to only 4 bar instead of 3.
This misalignment is easily pinpointed if he gets the updated one-piece OPRV for early blocks (slightly smaller than 1-piece on '87+ cars). You'll find that you can insert the valve, but due to the slight misalignment, you won't be able to screw the threads in.
Pete's high and stuck oil-pressure will go away when he aligns his housing (Porsche could've and should've solved this problem with some locating dowel pins).
05-08-2003, 01:05 PM
#22
Addict
Lifetime Rennlist
Member
Lifetime Rennlist
Member
Thread Starter
Join Date: Nov 2001
Location: Dayton, Ohio
Posts: 7,262
Likes: 0
Received 0 Likes
on
0 Posts
</font><blockquote><font size="1" face="Verdana,Tahoma,Helvetica">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Helvetica">Originally posted by Danno:
<strong>(Porsche could've and should've solved this problem with some locating dowel pins).</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Helvetica">That would have been too easy
<strong>(Porsche could've and should've solved this problem with some locating dowel pins).</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Helvetica">That would have been too easy
05-08-2003, 02:18 PM
#23
Burning Brakes
Join Date: Jul 2002
Location: Northern Virginia
Posts: 761
Likes: 0
Received 0 Likes
on
0 Posts
Danno, think about it. When the oil is cold and thick the oil pressure is higher than when it is thin. Oil pressure is also a function of oil pump speed, the pump is driven at crank speed, so as engine speed increases so does the amount of oil being pumped. The OIL PRESSURE RELIEF! VALVE is there to make sure that under these conditions you do not, for example, blow up the oil filter by over pressurizing the system. When the engine is at operating temp the oil pressure rel. valve is closed. The oil pressure is Not being reduced by the valve, what you see on the gauge is all the pressure the pump is putting out.
