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O Ring Source?

michbc3

Well-Known Member
Hi Gang - I seem to have an oil leak at the oil cooler adapter. So I'm looking for SEAL, OIL CLR ADAP, "O" RING, GM part number 25536843. My Pontiac dealer says that part has been discontinued. Anybody know of a source for these? Cost?

The dealer was nice enough to bring the parts list and drawing up on the screen and print it out for me.

Thanks, Bob Crow
 
are you talking about for the black oil cooler adapter? The o-ring on it is just off an oil filter, so just take one off an old filter and put it on the other side.
 
Nope. This is the "O" ring on the other side of the oil cooler adapter - toward the engine. Thanks for trying though...
 
Oops. Sometimes it's hard to help the "lost". I read you too fast Firebird 72. My apologies. If the gasket on the back side of the oil cooler adapter on the engine side is the same as the oil filter gasket, then you've given me good advice that I hastily overlooked.

I have not taken the oil cooler adapter off the car yet. I wanted to be prepared with a new gasket prior to dis-assembling. So it looks like I've got to take it off anyway to see what I've got. If I find out anything unexpected, I'll post a follow up note about it.

When GM desribed this as an "O" ring, I imagined something different than a flat, but round gasket as found on an oil filter. I was thinking of a round geometry profile - not flat. That may be where I've gone wrong here.

Thanks much, Bob Crow/michbc3
 
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Oops. Sometimes it's hard to help the "lost". I read you too fast Firebird 72. My apologies. If the gasket on the back side of the oil cooler adapter on the engine side is the same as the oil filter gasket, then you've given me good advice that I hastily overlooked.

I have not taken the oil cooler adapter off the car yet. I wanted to be prepared with a new gasket prior to dis-assembling. So it looks like I've got to take it off anyway to see what I've got. If I find out anything unexpected, I'll post a follow up note about it.

When GM desribed this as an "O" ring, I imagined something different than a flat, but round gasket as found on an oil filter. I was thinking of a round geometry profile - not flat. That may be where I've gone wrong here.

Thanks much, Bob Crow/michbc3
yup that should be the one. The oil cooler comes off with the large nut through the center and then the backside looks the same as the front. I didn't believe it the first time I heard it but I replaced mine the last time I changed my filter just to take a look even.
 
If you need the round stock O-ring and not the square stock O-ring I have them. And you can have one for free!

Just PM me when you figure out which ring you need.
 
Here's mine, and you can see how it was chewed up and that an actual chunk came off the lip of the adaptor. FWIW, I believe it became loose and the use of the longer GN oil filter helped it along it's path of destruction by banging on the idler arm.

...
pumpadaptor-1.jpg
 
This probably qualifies as a new topic, but here goes. Every oil leak problem on my Trans Am has been fixed except for one. As you know, these RWD 3.8 L V-6 engines use an externally mounted oil pump coming off of the front of the engine. The oil pump housing that holds the gears (which is part of the front cover) was not machined perfectly flat at the factory. So, the mating pump cover doesn't seal well - even though they use a gasket in-between. The gasket is about 0.007" thick. I believe that ALL GM 3.8L RWD engines, turbo or not are made this way. So there are probably a lot of leakers out there.


To fix this would require removal of the front cover. Then the oil pump housing could be machined perfectly flat. Then you could probably double up the oil pump cover gaskets to prevent the gears from binding against the cover when it is installed.


I'm having the pump put back together with a single, normal gasket tonight. This will result in an occasional drip - but not a flood. My brother and a local mechanic have removed and installed it - 3 times - trying different things. A "double gasket" idea resulted in an unacceptable oil pressure drop - and still leaked externally anyway. When warm, the oil pressure was down to only about 5 psi at idle. NG.


I don't have aftermarket "wider" oil pump gears and the metal spacer that comes with them. Perhaps the "factory" flatness problem is one reason why people use the aftermarket components - with thicker gaskets.


My brother's business partner has a Buick GNX, purchased new. We looked at it today. It has 20,000 miles on it and was "baby'd". Yes, the GNX oil pump is dripping - right where my car is dripping..
 
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