Retorqueing after thermal cycling is a good idea but not brass nuts, they are too soft and may strip out.
The only reason a carbon gasket will fail is if air/ exhaust is able to pass by it causing it to oxidize . I would take a real close look at your flanges. Are they lining up properly? Is there any nicks or any other imperfections in the mating surfaces that may cause mis- alinement's ? You would be looking for any cuts or burrs that would damage the integrity of your sealing media. Tighten your bolts in sequence, assuring that you have a even compression of the gasket. Torque in increments 1/3 of the end result you wish to achieve and then once around to check. Whenever you touch one bolt, it changes to values of the other two. Hope this helps. If the women don't find you handsome, they should at least find you handy. Red Green ----- Original Message ----- From: "Jim Thompson" <[email protected]> To: "The Chevelle Mailing List" <[email protected]> Sent: Friday, October 15, 2010 8:28:51 PM Subject: Re: [Chevelle-list] Exhaust gaskets (Donuts) Help! I never had a gasket fall apart. I suggest new studs, use brass nuts, and locktite. Retighten nuts after an initial warm up period and then again a month later. From: [email protected] [mailto:[email protected]] On Behalf Of [email protected] Sent: Tuesday, October 12, 2010 5:03 PM To: [email protected] Subject: Re: [Chevelle-list] Exhaust gaskets (Donuts) Help! I am having a tough time keeping the donut gasket between the manifold and the exhaust pipe from disintegrating. After installation, it takes about 3-4 months of very little driving and they start leaking again. I have been told that there are metal gaskets (poss copper?) and regular donut gaskets with a metal tube insert that helps the heat/exhaust flow through with less stress to the donut. I have not seen anything like what I am describing and wondered if there was someone out there that had some experience with this problem that they could share. Thanks, Ed 70 Chevelle SS Convertible
