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  • 1965 - 1973 Classic Mustangs -General/Talk-
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Heddman header exhaust leak... how to get rid of it?

  • Thread starter Thread starter SadbutTrue
  • Start date Start date Dec 16, 2003

SadbutTrue

Founding Member
May 1, 2002
2,390
4
49
Granada Hills, California
Dec 16, 2003
#1
  • Dec 16, 2003
  • #1
My heddmans have that annoying clicking leak at the flanges, which I remember several other people having. I also remember a few of them fixing it, but I don't remember how... anyone?
 
F

Fostang

Founding Member
May 8, 2002
1,400
0
36
Stockton, Ca
Dec 16, 2003
#2
  • Dec 16, 2003
  • #2
Did you use the included gaskets that was your first mistake. Get some mr. gaskets and be done with it.

btw: check your pm's
 

Gummi Bear

New Member
Sep 29, 2003
86
0
0
Arlington, Texas
Dec 16, 2003
#3
  • Dec 16, 2003
  • #3
SadbutTrue said:
My heddmans have that annoying clicking leak at the flanges, which I remember several other people having. I also remember a few of them fixing it, but I don't remember how... anyone?
Click to expand...
First get some decent gaskets, the fibrous ones that come with them leave some to be desired. Get some of the soft aluminum or copper ones (several different manufacturers). Second, replace the low grade nuts and bolts with some grade 8 and for extra insurance I used lockwashers and nyloc nuts. I go offroading pretty often and haven't had a leak in ages.
 
1

10secgoal

Active Member
Dec 1, 2003
2,801
3
49
San Diego
Dec 16, 2003
#4
  • Dec 16, 2003
  • #4
Don't waste your money on the dead soft aluminum or copper, they seal the first time but not the second. Just spend the $15 at autozone for the mr gasket. If that STILL doesn't work, take them off and cut all the flanges before you scrap them. This makes it so when you tighten the primary, you can do them individually. Then if another one leaks later down the road, you cut up another gasket and do only one primary instead of replacing them all.
 

TurboDoctor

Founding Member
Jan 27, 2002
1,008
2
38
San Marcos, Texas(Austin)
Dec 16, 2003
#5
  • Dec 16, 2003
  • #5
Thats how I do my headers also. I Cut the mounting flanges between every tube. I also use studs not bolts. You can buy studs from anywhere and they work alot better than bolts. I had a pair of hookers on my 62 ss that would not stop leaking. So i took some flat metal and traced the gasket onto it and cut it out and installed it between the gasket and flange to give the flange more compression on the gasket. Stopped all my leaks.
 

HookandLadder

Founding Member
Feb 17, 2001
261
0
17
St Louis
Dec 16, 2003
#6
  • Dec 16, 2003
  • #6
Make sure the flange is square. If not, heat and beat it flat. A good exhaust shop can do it for you if you don't have a torch.
 
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