Advice & WTB OPRV
#1
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So I had my head rebuilt by a very reputable machine shop who does work for several racers on the NASCAR circuit, but not being real familiar with Porsche engines the machinist did not do anything with the relief valve in the head. My question is what is your advice on what I should do.
A). remove and replace the valve or at least clean it up
b). not worry about it
I am also looking for a one piece OPRV and if anyone has an extra balance shaft bearing that they would like to part with I need both.
Thanks..
A). remove and replace the valve or at least clean it up
b). not worry about it
I am also looking for a one piece OPRV and if anyone has an extra balance shaft bearing that they would like to part with I need both.
Thanks..
#2
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If the head was surfaced you should remove the relief valve and make sure there is no metal filings in there.
There are several different types of one piece OPRV…you need ot say what year.
There are also two different types of rear balance shaft bearings…need to know year and does it have separate bearing caps.
There are several different types of one piece OPRV…you need ot say what year.
There are also two different types of rear balance shaft bearings…need to know year and does it have separate bearing caps.
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Sorry about that was in a hurry. 86 951. Looking for the balance shaft bearings located in the front of the engine. I guess they call them the bearing shells. Part number is:
944.101.125.02 I believe.
Is is fairly easy to do the relief valve in the head. Sounds pretty straight forward, but Murphys law I am sure will apply.
944.101.125.02 I believe.
Is is fairly easy to do the relief valve in the head. Sounds pretty straight forward, but Murphys law I am sure will apply.
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The parts for the cylinder head valve are dirt cheap. $5 total. I just bought them last week from pelican.
There's a 3 piece one and a one piece unit that's $300 or so. No functionality difference from my reading, and neither supercedes the other.
There's a 3 piece one and a one piece unit that's $300 or so. No functionality difference from my reading, and neither supercedes the other.
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The 3 piece OPRV was replaced by the 1 piece design in 87 (these are not interchangeable). Porsche also introduced a 1 piece OPRV that replaces the earlier (pre 87) 3 piece version.
The 3 piece design has a tendency to fail if it has been taken apart. The wear patterns don’t mesh well if it is disturbed.
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BUZZZZZ. – wrong answer! Thanks for playing and please pick up your consolation prize on your way out….![Smilie](https://rennlist.com/forums/images/smilies/smile.gif)
The 3 piece OPRV was replaced by the 1 piece design in 87 (these are not interchangeable). Porsche also introduced a 1 piece OPRV that replaces the earlier (pre 87) 3 piece version.
The 3 piece design has a tendency to fail if it has been taken apart. The wear patterns don’t mesh well if it is disturbed.
![Smilie](https://rennlist.com/forums/images/smilies/smile.gif)
The 3 piece OPRV was replaced by the 1 piece design in 87 (these are not interchangeable). Porsche also introduced a 1 piece OPRV that replaces the earlier (pre 87) 3 piece version.
The 3 piece design has a tendency to fail if it has been taken apart. The wear patterns don’t mesh well if it is disturbed.