Header gasket seal issue!!
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Instructor
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Header gasket seal issue!!
I have heddman long tube headers on a 87 L98 motor. My question is has anyone else had a problem getting them to stay sealed to the stock head? I even went as far as putting two of the crushed foil looking gaskets on ( as reccommended by "mechanic") Supposed to provide a better seal. Definately took most of the beer run fund. Anyone got any ideas on this? 
Race Director
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From: The Top of Utah
After they have warmed up and cooled off, retighten them. Do this everytime they are warmed up for the first few times. After that keep checking them. You will soon learn that checking and retightening is no longer necessary.
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Thread Starter
Instructor
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Right. i did that right before i started it every time and a few times when it was running. Now it has been about a year and i still have leaks on both sides between 4 and 6 and 3 and 5 coming up towards the hood and out.
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From: Good health is merely the slowest possible rate at which one can die
St. Jude Donor '04-'05-'06-'07
This is due for the most part to the thin 1/4" flanges on these headers. This may surprise you, but I've seen the cheap paper gaskets like the ones that come with these work better than anything on them.
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From: Slidell Louisiana
Originally Posted by Corvette Kid NC
This is due for the most part to the thin 1/4" flanges on these headers. This may surprise you, but I've seen the cheap paper gaskets like the ones that come with these work better than anything on them.
Plain old Mr. Gasket header gaskets, work OK with cheap headers! However, in my experience headers with thin flanges require a lot of maintenance to keep them sealed!
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Large Impressive Member
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From: Good health is merely the slowest possible rate at which one can die
St. Jude Donor '04-'05-'06-'07
Originally Posted by aboatguy
Are your header flanges straight (true)? If not they will continue to eat gaskets.
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From: The Top of Utah
Originally Posted by Mtrhd329
Now it has been about a year and i still have leaks on both sides between 4 and 6 and 3 and 5 coming up towards the hood and out.
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Race Director
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From: Slidell Louisiana
Originally Posted by Corvette Kid NC
With Hedmans, once they've been tightened a few times, probably not.
Your probably right!!! But if the flanges are warped, it is going to be tough to get it to seal and harder to keep it sealed.
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From: Slidell Louisiana
Originally Posted by CFI-EFI
Your clue, here, is in the word, "still". Once they leak you may never get them to seal without changing gaskets. The leaking hot exhaust gases often burn a channel in the gasket that further tightening can't fix.
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His comments about using two sets makes me think that he may have tried one set at first: and leads me to believe that he has an uneven gasket mating surface.
Initial post with Aluminum gaskets
Originally Posted by Mtrhd329
I have heddman long tube headers on a 87 L98 motor. My question is has anyone else had a problem getting them to stay sealed to the stock head? I even went as far as putting two of the crushed foil looking gaskets on ( as reccommended by "mechanic") Supposed to provide a better seal. Definately took most of the beer run fund. Anyone got any ideas on this?
Originally Posted by Mtrhd329
i tried a set and they blew out. would two sets help seal it better?
Last edited by aboatguy; Oct 9, 2005 at 09:11 PM.
Team Owner
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From: SE NY
Cruise-In II Veteran
I was using composite gaskets with a perforated metal core on the IROC and they constantly would leak.
Finally I found a composite gasket with solid metal core and they have been leak free for well over a year.
Finally I found a composite gasket with solid metal core and they have been leak free for well over a year.
Melting Slicks
Joined: May 2001
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From: Raleigh, NC
I fought header leaks for almost a year on a twin turbo Mustang I built with a buddy. What finally solved it for us was copper header gaskets, and a thin layer of orange RTV on each side.
Your problems may stem from thin flanges, while ours came from back pressure, but that's what cured our problems. You may never get the Hedman's to seal right.
Good luck!
Your problems may stem from thin flanges, while ours came from back pressure, but that's what cured our problems. You may never get the Hedman's to seal right.
Good luck!