Make Exhaust Gaskets?

Hello,

mixed info but I’m hearing that there was not an exhaust manifold gasket for the 198’s. Also knowing parts are hard to find but haven’t located one either. Seen a few videos of making a gasket with copper sheeting.

anyone know about this?

 

I have only recently started working with the Buick V6 engines, but when I was in my teens and early twenties I owned an old Buick, and I remember something from the shop manual I had.

On the old engines they didn't even use gaskets for the exhaust manifolds installed at the factory. They used a "Special Compound" on the joints. As strange as it sounds the manual said that when installing a new manifold to coat the mating surface with a mixture of oil and graphite. I did that on a 56 Century using 90wt gear oil with powdered graphite mixed in to a consistency of a rather fluid paste. Applied the stuff to the mating surfaces with a small paint brush and it worked fine. I drove that car for a few years and it never leaked. The 198 Fireball V6 is a direct descendant of that old "Nailhead", so you could try that.

 

This stuff is expensive but good. Might work.

Deacon 8875-THIN (10.3 oz. Tube) High Temperature Sealant, 150°F to 1800°F | eBay

 

When I replaced my headers I used hi-temp silicone, no gasket. 8 years now and still perfect. Previously was the usual header/gasket maintenance headache.

 

I think the "iron on iron" exhaust manifold sealing has been going on a long time. The 198 is a comparatively modern design, and it would not surprise me if these engines came from the factory with no gasket. This works better than a flat composition gasket, which will blow out eventually. In the mid-70s, the mfrs also did away with the composition gasket sealing the pipe to the manifold, at first substituting an iron ring, and later casting the sealing surface into the manifold. Again, steel pipe bolts direct to the iron manifold.

 

I worked on a 1 owner, never apart, 1971 Buick GS, it had no exhaust gaskets and no leaks. If the mating surfaces are true, I'd try some high temp sealer with no gasket.

 

I made gaskets for my Tri Y header using Mr Gasket header gasket material. I also made Carb gaskets for my Weber and one off Cast aluminum intake manifold.Sourced from Summit Racing.



I made four sets at one time as I was all set up for it so why not



And the Carb gaskets these were made from some .060" rubberized stuff NAPA sells.



Combination of cutting out holes with the material sandwiched between two pieces of plywood using a Forseter bit and hammer tapping and X acto knife and even small leather punches.

 

Most modern engines don't use gaskets, they just use Hi-Temp RTV, hell, half the Headers you order anymore come with a tube of it, and they tell you not to use gaskets.

That being said, I won't use graphite composition style exhaust gaskets anymore. Not worth the trouble, because they're always guaranteed to blow out. I use a Soft Copper, or MLS style gasket, if I think I need one.

 

Iv purchased uncut exhaust gasket material on ebay it comes in handy quite often

 

Recently made exhaust header gaskets for my 225 with hedman headers. I used .041"annealed copper from McMaster-Carr that worked great and was easy to work with.No leaks and the flange and head surface are sealed.Worth the trouble for me.

 

I imagine since they took the asbestos out.

 

Its been a long time, but I believe the 198 and 225 are the same pattern. You should be able to use the 225 composition/metal gasket on your 198. Its unlikely the surfaces of the head and exhaust manifold are true enough to get away with no gasket, unless you have a machine shop skim them.
Soft copper sheet also makes a durable gasket for exhaust manifolds.
-Donny

 

I’ve got access to a laser cutter that I’ve used to cut gasket paper before, let me know if I can help.

 

I have made header gaskets from scratch for SBC and FE Block Fords from this Mr Gasket material and always thought them to be superior in sealing and life span. I've never seen a copper header gasket but then I only been playing with cars for 45 years. So anything is possible.

 

Free Shipping on Orders Over $99 at Summit Racing

 

OK now I have seen them

 

They're not something you really find at most FLAPS, just speed/race shops in my experience. A little pricey, but if you've got headers especially ones that consistently leak, they work great.