Using an Exhaust gasket

Midwest Tin

Well-known member
Having trouble installing exhaust clamp when using the cooper gasket. Any
Ideas or tips on using original exhaust clamp? Thanks in advance
 
The original setup did not have any gasket whatsoever the flange pipe seals against the area on the exhaust manifold with the clamp.
 
yep, I too found the gasket made things very difficult. So I now just use a sleeve with exhaust paste- it makes lining things up really easy too. Some people reckon it creates a hot spot but I've been running with these for over 50,000 miles no worries
 

Attachments

  • sleeve.jpg
    sleeve.jpg
    26.2 KB · Views: 24
I use paste only, no sleeve. It helps to thoroughly clean both the exhaust manifold and the pipe each time you try to make it up.
 
Take foil wrap around exhaust,folded in about 2-3 layers- No leaks!
 

Attachments

  • foil strip.jpg
    foil strip.jpg
    30.9 KB · Views: 49
  • foil complete.jpg
    foil complete.jpg
    32.7 KB · Views: 47
It is common to use a floor jack to hold the exhaust pipe in position while the clamp is installed. But leave the clamp a tiny bit loose and remove the floor jack. The floor jack can cant the exhaust pipe in a position where it does not seal well.

As you tighten the clamp, rock the exhaust pipe back and forth so that it will seek its proper position on the exhaust manifold.

If the flange on the exhaust pipe is in the proper shape it should seal well. Using a little cement as Duke suggested will help with the sealing.
 
I have dressed the mating surface of the exhaust manifold with a file while it is off the block. And also tweaked the flange of the muffler with a big ball peen hammer to conform to the manifold outlet. Anal, yes, but best time for this extra effort. I don’t think the exhaust manifold putty was as widely used then in my club.
 
The rear clamp, also called the muffler tail pipe clamp (A-5256), is often overlooked when trying to solve the problem of an exhaust leak between the pipe flange and exhaust manifold. When properly installed, the rear clamp allows the exhaust pipe to expand and move rearward as it heats up and then contracts towards the front when it cools. If the rear clamp is improperly installed so that there is no movement of the exhaust pipe there will be constant front and back force applied to the connection at the manifold and leaks will happen. Skeptical of how much the pipe moves? I was too so I marked it with a soap stone pencil and then drove the car. I was amazed to find the exhaust pipe had moved in the clamp 5/8 of an inch!
 
These slides may be useful:
 

Attachments

  • Muffler Pipe to Manifold Connection 176kb.jpg
    Muffler Pipe to Manifold Connection 176kb.jpg
    60.7 KB · Views: 61
  • Muffler Flange Forming Tool 159kb.jpg
    Muffler Flange Forming Tool 159kb.jpg
    53.5 KB · Views: 60
  • Muffler Pipe Clamp Installation 155kb.jpg
    Muffler Pipe Clamp Installation 155kb.jpg
    54.6 KB · Views: 66
Bob, In your last slide you show the original style clamp in the back. That is the proper clamp to use. It has a bent end so that the bolt and nut can be tightened without making the clamp so tight that the pipe cannot move.
 
FWIW, there are some aftermarket rear clamps out there that look close to original that were sold by Midas and others. They are a little bit smaller to fit the slightly smaller pipes on the mufflers that were also sold. When you attempt to fasten one of these onto an original-size tailpipe such as made by Aries, look out - they will bind and not let the tailpipe move as it should. To make sure you are ok, suggest that you use either a KNOWN original or one of Aries’ replacements. I use the insulated ones intended for the stainless Aries pipe to avoid rattles. (Many of these undersized replacement mufflers have a part number stamped on the body towards the forward bell, original mufflers did not have that. They are also about 4” shorter.)
 

Attachments

  • IMG_4673.jpg
    IMG_4673.jpg
    31.4 KB · Views: 12
Last edited:
One trick for the rear clamp is to use a Nylon insert nut so that the bolt can be tightened just enough to support the pipe but still allow movement. Or double nut the bolt.
 
Also depending on the muffler being used, some of the suppliers are making the flare that contacts the manifold a bit short and are very difficult to seal. The Aries muffler I am using works perfectly with the HT sealant. The only reason I noticed this was when I installed the new muffler and had the 2 parts next to each other, I noticed the difference in the flares. The old one had a bit of a leak. I unfortunately did not take pictures before I trashed the old muffler otherwise I would post them.
 
Back
Top