VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1929-1932 Exhaust manifold gasket - way to make seal tight?

Hi guys -

New Years Day was reasonably warm, so I took my '32 out. Unfortunately, the gasket for the exhaust pipe to the manifold blew out again. I've tried several times in the past to seal it tight. The two small bolts *are* a challenge to make it tight enough. Any suggestions I should try?

The gasket shouldn't blow out. I had a similar problem with my 30 coupe. The guy at the local muffler shop (MIDAS) found the problem. The engine pipe didn't have enough of a bend so it easily seperated from the manifold, just enough for an exhaoust leak. He was able to adjust the bend. That was three years and a couple of thousand miles ago.

As Karl31 says, the alignment has to be right. Obviously, both surfaces, pipe and manifold, have to be clean and smooth. Then also, I use Anti-Seize on high strength stainless steel bolts to lubricate so they can be drawn up really tight. Check and retighten after a few miles of "wiggling-in".

Well, I'll give it another try. The thread lubricant sounds helpful. I have a tube of that already.

It's the angle... it's the angle...

I've installed three of these and no two were the same. Packard Farm exhausts are great, but on one of my cars, I still had to take it in to the muffler shop to have the angle modified slightly.

Here's a tip: Take the manifold exhaust pipe (or a short spare piece of exhaust pipe) that has a flange on it and mate it up to the exhaust manifold. Do this without any physical restrictions like the engine side pans being mounted in place... Just move it around until the doughnut fits the BEST WAY between the pipe flange and the manifold opening. You might be surprised at what angle it mates at. This gives you an idea of what angle the first couple of bends on your exhaust pipe need to be at.


Sounds simplistic, but it was an eye-opener for me. Before that I used to burn out my doughnut gaskets about every 1,000 miles or so.

And, yes, ALWAYS use anti-seize on your bolts.

Loosen the pipe where it connects to the muffler so it can rotate freely.
Loosen/remove the manifold to exhaust pipe bolts/studs.
Clean the surfaces of the mounting flanges so no rust chunks are present.
Do not place the gasket in at this time.
Dry fit the manifold and exhaust pipe together and place a bright light so you can see if there are any air gaps that are not parallel to each other.
If air gaps are parallel, you can replace the gasket and tighten up the flange then tighten up the muffler clamp.
If the gap is not parallel, you may have to bend the exhaust pipe as previously suggested.
If the gap is off slightly you may also try to use the basic "doughnut" shaped exhaust manifold gasket found in any parts store.
Do not use SS studs as they are as strong as regular studs.
Purchase a regular set of new studs and Brass nuts.
I have used the doughnut gasket and it works as a long term "Quick Fix".
Since then, I have replace the engine and I was able to re-align the exhaust pipe to the manifold by the above method.
Just take the time to loosen everything up first then move it around to see if it will line up better.