Double gaskets on header exhaust outlet pipe

[acudanut]

I have seen this done, but does it seal better ?

[rickf]

No.

[acudanut]

Thanks Rick, does anyone else have a vote ?

[kmam]

No.

[mutt and jeff]

I just put mine back together after replacing the intake gasket and gooping up the exhaust manifold. I installed a new gasket in the header pipe flange and one worked fine. But, the new gasket I obtained from RAPCO appeared to be much thicker than the old gasket that came out in pieces. Since I had the silicone goop all over my hands, I gooped up both sides of this gasket as well and installed it.
What I am having a problem with is the next gasket in line from the bottom end of the header pipe going to the straight pipe in front of the muffler. Even with goop and a new gasket down there, I can't get that clamshell type clamp to tighten up enough to prevent an exhaust leak.

Good luck with your exhaust issue.

[m3a1]

Is the trouble with the gasket/seal, or the exhaust pipe? Or is it the clamp which is giving you trouble? Your pipe should have a flange, or lip on it over which the seal is placed and that lip goes into the next section, which also serves to align it. Deformation to that would probably be pretty obvious and you haven't said anything about that, so I'm betting your clamp is toast.

I just looked on eBay and found a new repro clamp almost immediately and, yes, it is horribly expensive... for a clamp, anyway....but if that's the final piece of your puzzle maybe you'll want to jump on it. They are notoriously weak at the junction of the clamp body and the tab for the bolt but when new, they work, so it's difficult to say they're a poor design. But, reusing an old one, you take your chances.

I may have a stray one laying around here somewhere...probably at the bottom of a box of other stuff. Please don't make me look for it. Buy the repro clamp.

Cheers,
TJ

[acudanut]

I am just replacing the one similar to the carb mount gasket.

[rickf]

You would be amazed at how many carbs are sent to me to be rebuilt and they have an exhaust gasket stuck to them instead of a carburetor gasket. Makes me wonder how many people are using carb gaskets on the exhaust and wondering why they blow out.

[acudanut]

You would be amazed at how many carbs are sent to me to be rebuilt and they have an exhaust gasket stuck to them instead of a carburetor gasket. Makes me wonder how many people are using carb gaskets on the exhaust and wondering why they blow out.

Carb Gaskets are too small for the exhaust type. Speaking of Carb rebuilds, I have 4-5 kits that are yours. Free if you want them. Not sure about all or what they contain. !! Cheers.

[rickf]

Do they have numbers on the box? I don't get much call for civilian carbs anymore. The only thing out there on the civilian vehicles is the few rare racing classes that still run stock carburetors. Between that and all out racing carbs there is not much left out there, And the racing guys do there own so I don't see them.

[acudanut]

I will look for part Numbers. They are carb parts for the M-151.
5 envelopes C131-350 or C181-350. (they are paper gaskets). I do have needles,springs and a few jets that are yours, if you want them.
The Only carbs I mess with are Civy Holley 750's.

[mutt and jeff]

Did not intend to hijack the thread, but, in my situation, I have ordered new clamps from AJP and will install them when they arrive. Appeared my old clamp would bottom out on the hardware and not seal. I held the muffler pipe and the header pipe together with a rachet strap while I installed the two sections of the clamp and thought I had a good seal with a new gasket, but still get exhaust leak around the clamp when the rachet strap is removed. Muffler is loose, so I don't think I am torqueing the connection.

[rickf]

You have got to get the pipes perfectly aligned before trying to clamp them together or you will just deform the clamp. Don't use the clamp to pull the pipes together. As I said in a post a while ago, you will need to twist and move the pipes around and eventually you will find the spot where they are perfect. You need to start at the front and work your way towards the back, you can't do a section in the middle without loosening all the pipes after it first.