exhaust manifold sealer

[k92]

To be factory correct, I plan on not using gaskets on the exhaust manifolds where they bolt up to the head. Do you guys have any problems with leaks or use any type of high temp sealer on them?

[VintageMusclecar]

As long as the manifolds are perfectly flat you shouldn't have any leaks. You could always have your local machinist give them a skim cut just to be sure.

If you want a little added insurance, a super-thin coat of Ultra-Copper silicone sealer works well in an exhaust environment.

Eric

[Alss]

[ QUOTE ]


If you want a little added insurance, a super-thin coat of Ultra-Copper silicone sealer works well in an exhaust environment.

Eric

[/ QUOTE ]

This is what I did..works great..hard to see or invisible if you are very carefull..Just a dab applied with your finger tip.

ALbert

[L78steve]

Has anyone ever have an exhaust manifold cut?I had a 455SD manifold cut once and it cost me $270.00.The machinist said the time is in the jig.I now use gaskets scribed and cut to each port, invisible to anyone over 45(age)and they do'nt blowout after 200 miles.

[70CitrusZ]

Imagine my surprise when I called a GM parts dept. asking for exhaust manifold gaskets and they said there was no such part from GM. They never used gaskets from new, so why would you need them now, unless the manifold surfaces are poor or warped.....I still use gaskets.

[k92]

Thanks for the responses. The exhaust ports on the heads were already milled,but nothing has been done to the manifolds yet.They are currently at Mcneish's getting refinished and I dont know if getting them cut would somehow damage the coating on them. I'll probably try the copper sealant just in case, hate those pesky exhaust leaks!!

[nuch_ss396]

Contact Jerry M and ask him to put a straight edge across
the flange surfaces. If they are problematic, ask Jerry
to get them fly cut.

Steve, I can't imagine why it cost you that much money to
get the 455 manifolds cut. It's a flat surface and somewhat
easy to indicate for flatness. Then, you just take a light
cut for cleanup. Unless I'm missing something, a skim cut
should be fairly easy to do. I will have that done to my
manifolds before I install them. 30+ years have to account
for a little warping I would expect.

Steve

[L78steve]

Once the jig is fabricated it is simple.But the manifolds have to be firmly held or chatter will occur.This will ruin the cutters and the manifolds.

[elcamino72]

I agree, have Jerry check them. I've gotten them machined in the past at a local shop and I forget what they charged me, but it wasn't much. Now I just trim the gaskets and you really don't see them however on a 1000pt car I would certainly not use gaskets.

[nuch_ss396]

Sounds like the perfect application for a surface grinder,
not a fly cutting operation.