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Discussion Starter #1
Can't seem to get my headers to seal for the life of me. Its been a apart 3 times first time it had percys seal for good gaskets which didn't seal. Did a search on here and found that copper RTV is the best to use, so I tried it out, had a small leak on the passenger side right away and within about 50 miles the passenger side blew out pretty bad. Did another search, on my first install i just put a 1/8" bead on the head instead of smearing it lightly on both surfaces. Took it apart and put the RTV on both the headers and heads and now it leaks way worse then it did before. Really don't feel like fooling around with it any more, any suggestions for me to try out? Did see that putting studs in to help line up the header can help a lot. If it makes a difference every time it leaked it was always leaking from the bottom of the ports. Thanks
 

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ARP studs helped me alot. Also with ease of assembley. You can spin the nuts on.
Not sure what kind of headers you have. If you have flipped shorties, you need to drill out the bolt holes to make them line up right. You can use a gasket upside down to mark it. Regular felpro gaskets should work, provided everything is lining up well. Put the headers on without turbos and stuff hanging off them.
Another thing you may want ot do is to see how it is lining up by putting an old gasket on the head (use studs), then put some prussian blue on the header and slip that on and see how it marks the gasket. I would be you are a little close to the edge in a few places. If everything is lined up and bolted down evenly, it should not leak.
Erich
 

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What headers are you using? I'd get them checked for flatness and possibly have them re-surfaced. Silicone RTV should have no problems sealing them if they are true and flat…but they will not seal anything that has major imperfections.
 

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Discussion Starter #4
They are pony down headers. Wont be able to pull them off tonight but I will tomorrow after work and see if they are truely flat and make sure they have no flaws.
 

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Had to gring mind a little for flatness. Start there the rtv is the only way to go.
 

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what I had to do after several tries I finally found something that worked for ME.
I used the copper gaskets along with the copper RTV. so far NO issues. I tried just gaskets and just RTV and it would only last for a little while.


Oh I wasnt greedy with the RTV either lol
 

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They are pony down headers. Wont be able to pull them off tonight but I will tomorrow after work and see if they are truely flat and make sure they have no flaws.
Flanges maybe warped some when they were being made. It would not take much for it to cause sealing issues and would be something hard to tell, well guess depending on what tools you have access too.

What heads are they on, are you 100% sure that the ports line up well with the heads and headers?
 

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Discussion Starter #9
Took the headers off today. Only 2 ports were leaking cylinders 2 and 8. On cylinder 6 there was a weld bead going completely around the tube that stuck up very little so I ground that down flat. It looked like both were small leaks so Iam going to guess that it was my mistake on the install. Put a flat edge on both headers and they seem true without warping. I made up 4 studs to help me line them up(2 for each side) but I am not sure yet if there is even room to use them on the passenger side. Please correct me if Iam wrong: put a thin layer on both surfaces about 1/16" and let it set up for about 1/2 hour then put the header on with the bolts finger tight then crank them down from the inside out?

Should I try copper gaskets and rtv?
 
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