Do the factory header gaskets go bad?
Thread Starter
Racer
Joined: Apr 2003
Posts: 272
Likes: 0
From: Podunk IL
Do the factory header gaskets go bad?
I'm having what sounds like blow by from the factory header gaskets (the thin steel ones) under load. I made sure all the header bolts are tight, and it is still happening. I thought those gaskets never went bad?? I have stainless steel works headers if that matters. Please help if you can.
Safety Car
Joined: Sep 2003
Posts: 3,558
Likes: 2
From: Cape Coral FL
I had SW's for a while and didn't have your problem at the headers, but had leakage at the midsection joints. This was due to inadequate clamp pressure. I didn't torque the clamps down tight enough to seal the outside pipe to the inner one. I was afraid that if I torqued them any more I would strip them. If I had kept them on the car I would have purchased 3" band clamps and installed them. You can see if you are getting blowby if you look carefully at the side of the heads right where the pipe mates to the port. You will see carbon residue flaring out in a flat flame-like pattern. I had a stripped header bolt in the center of the flange and was getting that pattern(and blowby) from 2 cylinders. As far as flanges leaking I would check these things.
1) Are you absolutely sure you have the gaskets installed correctly?
2) When tightening header bolts you should always tighten from the inside out. The center ones first, then progressively to the flange ends. I even do it in 2 passes. I know, I'm a little retentive, but I don't get blowby.
3) After I tighten the bolts I check them after every 3-4 heat cycles and for about 3 weeks. Remember, those headers are stainless steel and the heads are aluminum and they expand and contract at different rates.
4) The last thing I did, just recently, was to put lockwashers on the header bolts.
5) You may have to get new factory gaskets, but I haven't changed mine and have had 2 sets of headers and had them on and off about 20 times.
1) Are you absolutely sure you have the gaskets installed correctly?
2) When tightening header bolts you should always tighten from the inside out. The center ones first, then progressively to the flange ends. I even do it in 2 passes. I know, I'm a little retentive, but I don't get blowby.
3) After I tighten the bolts I check them after every 3-4 heat cycles and for about 3 weeks. Remember, those headers are stainless steel and the heads are aluminum and they expand and contract at different rates.
4) The last thing I did, just recently, was to put lockwashers on the header bolts.
5) You may have to get new factory gaskets, but I haven't changed mine and have had 2 sets of headers and had them on and off about 20 times.
Last edited by ArKay99; Jul 28, 2004 at 11:07 AM.
Race Director
Joined: Jan 2000
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From: Lynnfield MA
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If you used the gaskets over again than I would change them out considering you should always go with new gaskets on an install such as headers. Cheap insurance...
