Exhaust/muffler connection

[30coupeguy]

When I removed the engine, the exhaust manifold connection to the muffler had a generous amount of hard substance around the mating surfaces and inside the clamp.

I looked kinda like furnace cement or something similar. Apparently it worked to seal the connection. I put it back together without any thing other than the clamp and I believe there is a leak.

Should a high temp sealer compound be used, and is there a type that works best? Is there a better idea?

thanks

burt

[pat in Santa Cruz]

the exhaust manifold can sag from heat and age, preventing a good seal on any muffler. Additionally, the cheaper repro mufflers do not fit any manifold well, and need sealant. The Aries fits a straight manifold well, but even at that, it is recommended to use a small amount of sealant.

[ford3]

first you need to make sure the header pipe and exhaust manifold line up in a straight line, if not there will be a leak there, put those two together before putting on muffler brace, and there is a asbostos type cloth that the dealers sell, it goed around the exhaust manifold and muffler header and then you install the clamp, ive used it and it works good, again make sure every thing lines up before installing clamp

[Charlie Stephens]

It has been years but I think I bought "muffler cement" at Pep Boys.

Charlie Stephens

[SeaSlugs]

yup tailpipe/muffler cement still exists, still looks like concrete when it dries.

[Willie Krash]

Sponsored Links (Register now to hide all advertisements)

I use aluminum foil. It seems to work.-

[Wick]

After you have the clamp tight,strike the side of the clamp with a hammer. You now can get another turn on the fasteners. Repeat this step a couple of times. this should stop the leak without using anything else.
Wick

[Christoph]

The poor quality Repro-Clamps the dealers sell nowadays
do not fit at all (same as mufflers).
Have a look on them before you use them.
Repro-Clamps most common have some 2-point-contact to the
flange and they brake just by tightening (you will not have to use
a hammer to crush them).
With this modern junk i use this metal-adapter-to-put-inside-flange
plus exhaust cement. (i found this asbestos material to be way to thick).

Most original rigg should be fine just by tightening.

[Kurt in NJ]

Furnace cement can be used to help seal a damaged flange, I just replaced my cracked manifold --I had been using furnace cement to seal the cracks ---but that had to be reapplied each time

On my Smiths compresser I used componets that I didn't consider good enough for a road driven car, on that flange I used a sleeve from a chevy pipe to ex maniflod connection---it fit both the manifold and the frontpipe and has stayed sealed for 20+ years ---it was from a mid 70s 350

I had originally planned on waiting for the muffler to fall off due to rust before replacing the ex manifold---but the manifold looked to be falling off first

Wicks tapping with a hammer while tightening is a good method I also use.

[Mitch//pa]

i just use the little pipe that goes inside available from the jobbers. never had a leak, needed cement or had to use that crappy flange gasket that i once threw as far as i could.

[ericr]

Originally Posted by Mitch//pa

i just use the little pipe that goes inside available from the jobbers. never had a leak, needed cement or had to use that crappy flange gasket that i once threw as far as i could.

I was wondering about that....doesn't the pipe create some back pressure?

[Mitch//pa]

Originally Posted by ericr

I was wondering about that....doesn't the pipe create some back pressure?

not at all it fits tightly inside on both ends and is no different from any exhaust where one pipe slides into another

[rollingsculpture]

the real trick to getting a good seal is this ,1 as stated above make sure the manifold pipe and the muffler pipe are in exact alignment if they are at an angle to each other than place a large 1 1/2 pipe down the muffler pipe and bend until it is in line 2 and this is the trick , put a jack under the muffler pipe at the point where it bends to go up to the manifold put just enough pressure on the muffler to seat it firmly against the manifold connection , inspect the entire circumference of the connection for any gap in the flange if all is flat and looks sealed put on your clamp and tighten away

[johnbuckley]

Originally Posted by rollingsculpture

make sure the manifold pipe and the muffler pipe are in exact alignment

which is what the sleeve that Mitch PA recommends does. When fitting the exhaust system without help I suspend the rear section of with a bit of string at about the right height, fix it at the manifold using the internal sleeve ( just for extra reassurance I use a dab of cement as well) get it snug to the manifold with a jack, clamp it, and then finally do the rear bracket.

[Mitch//pa]

along with aligning,,it also diverts the exhaust pressure from trying to escape out the flange connection. i think its a great 2.00 idea
p.s. when i threw the gasket i almost hit a customer walking into the shop...