mmmm donnuts!!!

1928Pickuppain

Senior Member
So over the last few months i have noticed a leak around my donnut gaskit. Well last week driveing to school it blew compleatley and the pipe is super lose, but it seems like the clamp is sitlll fully tight do these clamps strech or is it just the donnut gaskit missing causing it to be loose im hopefully going to replace it tonight Its difficult not having my truck for a week. (try halling a load of bricks in a jeep dosent work well) never minde me and my girl friend working 25 miles apart and going to school on differnet days. any advice on replaceing it would be helpfull.
 
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I think he's talking about the exhaust flange. Sounds like to me you have the clamp on us-side-down. there is a large and small size to each side.

I do not use a gasket. But I put some "muffler repair cement on the flange just before putting it together.

Works for me.

just my W.A.G. at the problem.

Jb
 
Donut Gasket= Exhaust manifold to muffler gasket..

I would try a lot of pen. Oil; the heat and rust will "weld" these things in place.. Have a replacement on hand and either use force or file it off.

BTW-- running without a donut can let major exhaust fumes into cab area. BE CAREFUL. :eek:

D
 
I don't have a gasket and it doesn't leak. I'm not sure how a donut gasket would work with the clamp?
 
I use an Aries muffler and it seals well. I use a thin layer of muffler cement to be sure, but it may not be needed.

Like Mitch, I can't see how you could clamp the flange if you stuff a donut gasket in there.

If the flange isn't well formed, but the muffler is still good, then take it to a muffler shop and have them reform the flange.
 
The donnut gaskit is small realy thin ring of copper that sits up on you exaust pupe and also has a ridge that drops inside when tightend to the manafold. The copper comresses making a seal. All cars have them even steam engines can have them so in places had obsorb vibrations they can move with out cracking as say a solid conection. Modern ones look like there made of lead and about 1/2" thick and look like a donnut. If you dont have one your two pipes will never seal corretley and you will have exaust fumes coming into the cabin and even flames (small ones) comeing out of the conection that could potentialy light driping gass on fire. Thanks for the knowledge that the flange Clamp has a large side and a small side. The Gaskit is not more than 3/32ths thick.
 
Just put an Aries muffler on my 29 that had a straight pipe (too loud). Used the gasket sealant mentioned above with a new clamp. Didn't use the copper gasket even though I had one, seemed like it would actually make sealing the connection more difficult (or not, to each their own). No leaks for me. I'll add, the Aries muffler is great!
 
The original exhaust system did not use a donut gasket. It was manifold to pipe connection. I use muffler sealer too on mine. On difficult to seal issues they do make an exhaust seal as 1928pickuppain describes, but was not originally used. Open up your clamp and see what you have, Tom had a good sugestion about the flange.
 
That's correct that modern cars have the exhaust donut and have had them for many years, but they also use a different clamp that is made for such a gasket.

The muffler flange and clamp of the original style does a very good job of sealing the pipe to the manifold.

I'd say you are more likely to get exhaust fumes in from the tail pipe exhaust getting through the same hole that the mice use to get inside the car. Just where the heck is that hole?????????:(
 
Tried putting that copper exh pipe seal on when I had maniflds off and gave up trying to get everything to fit, ended up usin the sealer as others have suggested.
Paul in CT
 
The easiest fix for the exhaust leak is to fold flat 4 layers of common aluminum foil to 1" flat, shape around exhaust flange, install clamps, no more leaks.
 
I fixed it last night. from the vibrations nuts on the clamp bolts were so rusted that thred striped off the shaft replaced bolts not donnut gaskit (lost it on the walk to the grage some were ) no leeks.
 
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