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briankeithsmith briankeithsmith is offline
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Join Date: Apr 2002
Location: Concord, NC
Posts: 810
All 6 cylinder base gaskets leak

Well my first rebuild didn't go as well as I had hoped. It runs great, and sounds awesome, but all 6 of the cylinder base gaskets leak.

As part of the rebuild I upgraded to fully finned 3.3L P&Cs from Mahle. During the assembly I used the stock .25mm copper gasket that came with the gasket set that I bought from EBS for my car, and then I used the aluminum shim that goes between the cylinder and the head, as you are suppose to with the fully finned cylinders.

I installed the copper gaskets dry. I also had installed ARP head studs and I used their torque value of 36 ft/lbs with their ARP moly lube on the washers and nuts.

The problem I have is that all 6 cylinder base gaskets leak.

So my question is this : should I have used a thicker copper base gasket with that type of cylinder? Or did I use the right gasket for my application. With the 3.3 fully finned cylinders is there another way that is commonly used to seal the cylinders to a 930 case?

We did not use any form of loctite on the copper gaskets for the following reason : once we placed the cooling tin on the cylinders, the cylinders were quite tight, and we were afraid that if we used loctite that it might harden in some areas before we actually got ready to tighten the head studs, which would have given an improper seal.

As a side note: on my prior 2 rebuilds, not performed by me, the base gaskets also leaked initially, but after the engine was ran for a while, they sealed themselves it seemed. Example: on both rebuilds at my first track event the back of the car would be covered in oil which appeared to have come from the base gasket area. However, after that first track event, I had nothing more than the occasional drop of oil, normally associated with our engines.

Any advice? I've read some of the other posts, regarding cylinder base gasket leaks and it seems like everyone says to tear it down and do it again. Only problem is that I'm not sure what I'd do differently.


Brian Keith Smith
Competition Custom Paint
1983 930
My Track Videos
TEC3 EFI Conversion on 1983 930
Old 08-21-2004, 06:40 PM
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