I took my car in to my mechanic the other day to have the alignment done and he mentioned to me that my "turbo pipe O Ring is leaking". Where is that, how is it effecting the performance of my car, and how hard would it be for me to fix/replace?

Brian

I did this (relatively) simple repair on my previous 780. The o-ring your mechanic is talking about is at the base of a return line approx 1/2" in diameter that comes out of the bottom of your oil-cooled turbo and back into the block for collection, filtering, and redistribution. It's not under pressure, but even a slight leak or crack in the o-ring will cause seepage at least. In my case, the PO had attempted to repair this (rather poorly) with blue p-tex. This was not the only thing he attempted to repair with said substance, and it took me the better part of a year to un-f**k all his half-assed work. In other words, just putting a ring of goo around the pipe will not permanently solve your problem. Shell out the five bux or so to get the new o-ring, undo the two bolts, finagle the pipe out of the block, remove the old o-ring or what's left of it, and re-finagle the pipe back into place. I found that this was the trickiest part, as it was a fairly tight fit and I didn't want to catch the o-ring up against the sharp edge of the end of the pipe and cut it accidentally. I don't know for sure what this gasket is that others have spoken of (perhaps that's at the turbo end of the return pipe, but I didn't screw with it). I found this to be a quick 15 minute job that saved me from having to constantly check the oil level and constantly change the "car diaper" in my garage. Of course, I had access to a lift, so that made the job significantly easier. Good luck, and YOU CAN DO IT!!!

-Jon '91 Coupe 150K "Gustaf"

My only experience in this area was when I was bolting things back together after removing the head and replacing the turbo on my 82 GLT.

Someone here suggested using a high grade silicone in conjunction with the new O ring on the turbo pipe/block connection. It worked like a charm. The wet silicone acts like a lube and allows the O ring to move freely so it doesn't bind when inserting the pipe into the block. I cleaned all the surfaces with lacquer thinner prior to assembly to insure good adhesion. It has not seeped at all since assembly (1 year/11,000 miles).

I use the same procedure when installing the O ring between the heater pipe and waterpump (adding a modest coating of silicone to the rubber seal between the waterpump and the head as well) It has contributed to a good track record in that area as well.

Randy

I've had to redo the repair I paid the #$%@#% dealer (355 Toyota/Volvo in Rockville, MD) to do. The dealer shop/mech had simply slapped on some copper-colored high temp selicone goo that fixed the leak for three months (You can do this if you clean the area real good...no guarantees how long it will last!).

It took about 15 minutes to get under the car and remove the two bolts that hold the tube to the bottom of the turbo and winkle the tube out of the block...I don't remember if I had to remove the oil filter or not but if I did I probably threw on a new one for GP. It took another ten minutes or so to get the new seals and (old) tube back in place and buttoned up...I used blue loctite on the turbo bolts and torqued them according to the service manual. IMHO, it's no worse a job than changing oil (the real problem is getting to the oil filter) on a 7xx, just takes a little longer.

The O ring and turbo gasket are about $5.

When I removed my tube I found a mostly disintegrated O-ring and an old gasket at the turbo...the dealer had obviously cut corners and NOT installed the gasket/O-ring. I put the parts in a baggie and went back to the service department and, to their credit, they refunded/credited my money.

Probably the stupid O-ring where the oil return pipe enters the block.

It creates a leak, and eventually a puddle in your driveway.

It doesn't directly influence performance 'til you run outta oil, then your performance (and your bank account) are toast.

It's not a fun repair. Neither is replacing the O-ring.

Don Foster (near Cape Cod, MA)