351c exhaust gasket donut question

[72HCODE]

Question does the dual exhaust on a 351 Cleveland with boss manifolds use a doughnut exhaust gasket between the exhaust manifold and the H pipe?

I can not find mention of one. my exhaust pipe is flanged to accept the flair on the manifolds I have, I never used a gasket there before but I know I have a small leak from that mating point, plan is to use some exhaust sealant at that point unless there really is a gasket designed for it.. If there is one I need a part number for it.

I found a C9ZZ-9450-D gasket but there is no way it would fit the manifold and pipe I have.

 

[kcmash]

I have never seen a donut gasket on a 351c exhaust manifold. To stop leaks I put a floor jack under the pipe right at the bend and add slight up pressure. I tighten the flange nuts with the jack in place and walla, the leak is gone.

Question does the dual exhaust on a 351 Cleveland with boss manifolds use a doughnut exhaust gasket between the exhaust manifold and the H pipe?

I can not find mention of one. my exhaust pipe is flanged to accept the flair on the manifolds I have, I never used a gasket there before but I know I have a small leak from that mating point, plan is to use some exhaust sealant at that point unless there really is a gasket designed for it.. If there is one I need a part number for it.

I found a C9ZZ-9450-D gasket but there is no way it would fit the manifold and pipe I have.

 

[c9zx]

No doughnut except on police cars. A small amount of RTV on both mating surfaces, tighten, and let it completely cure. It won't leak and it won't burn out. Same for header gaskets. Chuck

 

[72HCODE]

Thanks for confirmation.

I used high temp ext sealer and finished the exhaust today.. 2 projects down. Yippy.

No doughnut except on police cars. A small amount of RTV on both mating surfaces, tighten, and let it completely cure. It won't leak and it won't burn out. Same for header gaskets. Chuck

 

[c9zx]

Good for you. The hobby is a lot more fun when things go well. Chuck

 

[Totalled]

I've had great luck with the ultra copper high temp rtv on exhaust systems. Particularly FE header gaskets.

 

[mycoses]

I found the metal to metal seal technique required excessive pressure tightening on the exhaust stud nut so I purchased some bulk pieces of exhaust gasket from summit and cut out a doughnut shaped piece of gasket and placed it over the end of the exh manifold and tightened the pipe over the gasket and got a good seal with moderate pressure on the stud nut.