Leaky turbo oil drain line/gasket

[QuickWE4]

I've noticed that, ever since I installed my TA49, I can't get the oil return line to stop seeping. I mean, it doesn't leak like a sieve, but every so often, I'll see a few drops that have leaked down from the gasket on to the metal drain line.

Now, I replaced this gasket when I did the turbo, and the bolts are good and tight. Is there any trick to preventing this leak or is it just symptomatic of these cars? I don't drive the car alot - perhaps it takes some time for the gasket to seat with a change in temp? Would two gaskets work?

Just looking for some quick thoughts.

Rich

 

[machinegun]

You are going to hate to hear this, but I had the same problem at one time after a new TE44. It turned out the exhaust side oil seal was leaking. The way it ran down it looked like the return line seal. After numerous times of trying with no luck I pulled the turbo. That ia when I found the oil coming from the exhaust housing and soaking the outside of the return line making me think it was the return. I got mine fixed as it was still under warranty.

 

[Jimn8or]

Replace the 2, 13mm drive bolts with studs, install new gasket, zip on 2 SS nuts and enjoy a leak-free connection. $2, a little time and your leak won't be from here anymore.
HTH
Jim

 

[MSDGN]

Where did you get the gasket from?...if it's not a GM gasket then that could be your problem...have seen many of them leak...the GM ones are thicker and seal better...

 

[MSDGN]

Sorry that last post didn't come out right...should read that I've seen many of the non-GM gaskets leak...

 

[QuickWE4]

I should have also noted that I've only got 30 miles on the turbo and I can clearly see a little bit of seepage coming directly from the seal - I mean, it's like a tiny film of oil, not really a leak.

Thanks Jim. I like the idea of the studs.

What size threads and nuts do I purchase for this?

BTW - the gasket came with the turbo from John Craig. Anybody got the part number or know vendors that sell original GM gaskets?

TIA
Rich

 

[TurboRegal84]

The threads for the Turbo Drain Line flange are 8MM X 1.25. You would need the correct thread pitch on the studs that you buy.

ie: If you buy the 8MM X 1.25 on one 1/2 of the stud, and the other half is (Place thread size here) you would need the nuts for the (Place thread size here) side of the stud.


Some threads come with different pitches on each 1/2 of them.

 

[Louie L.]

The GM oil drainback gaskets are considerably thicker.many times a GMgasket will fix the leak. Some times the drain back flange maynot be flat. I ususally coat them very, very lightly with RTV.

 

[TurboDave]

The GM gaskets are an easy solution, and uncomplicated. You probably got the paper thin gaskets that seem to come from all the turbo vendors. Unfortunately those are the WRONG gaskets and will always leek unless you have perfect mating surfaces and really goop them up with RTV.

The GM gaskets (part # 25537227) are the only way to go. Can be gotten from any GM dealer. I got my last batch from a chevy dealer because they weren't in stock at the Buick house.

They are very thick, and only need a light coat of RTV.
What I do is make sure both surfaces are perfectly clean. lightly coat one side of the gasket and place it on the drain back tube.
Let dry for at least 12 hours. put a light coat on the surface that meets the turbo, Just before placing the turbo in place.
Mount turbo and torque to specs. Let dry for sevaral hours.

Enjoy leak free operation.

It usually always comes back to one point. The right parts.

 

[JToups386]

I've had the same issue on one of mine, and did use GM gaskets to try and fix it. It turned out that my flange was slightly warped, and had to be mildly machine flattened. No biggie. However, the guy I sold my T to works for a GM dealer, and surprisingly found the entire drain line replacement still in stock, and just replaced it. I can't remember his price, but it was rather cheap in my opinion. I'm thinking in the $30-$40 realm. I would pursue what the other guys suggested first, and only go this route if yours is warped as much as mine was.

 

[QuickWE4]

Thanks guys...

The gasket I got from Limit E. was pretty substantial, but I'm gonna order some GM gaskets and I'm sure that'll take care of it.

JToups386:

I'm going to look into purchasing one of those assemblies as I thought that they were discontinued. Would be nice to keep one as a spare.

Thanks
Rich