• 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
351c exhaust gasket donut question
#1
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.
  Reply
#2
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.

72HCODE;185669 Wrote: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.
  Reply
#3
No doughnut except on police cars.Tongue 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
  Reply
#4
Thanks for confirmation.

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


c9zx;185704 Wrote:No doughnut except on police cars.Tongue 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
  Reply
#5
Good for you. The hobby is a lot more fun when things go well. Chuck
  Reply
#6
I've had great luck with the ultra copper high temp rtv on exhaust systems. Particularly FE header gaskets.

1973 Mach 1 Q code 351 4V, 9A paint, standard interior, 3.50 rear, C6 trans.
  Reply
#7
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.
  Reply
Share Thread:  


Possibly Related Threads...
Thread Author Replies Views Last Post
  What to do to 351c 4v heads? scgamecock 45 1,318 11-19-2018, 09:27 PM
Last Post: jpaz
  351C decals and or markings (M code 1971) Ryunker 0 204 10-25-2018, 06:21 PM
Last Post: Ryunker
  351C Fuel Delivery Problem Rumblefish 20 629 10-16-2018, 01:39 PM
Last Post: Fabrice
  Toploader question Jeff73Mach1 16 431 10-11-2018, 12:24 PM
Last Post: Jeff73Mach1
  What does it take to stroke a 351c scgamecock 6 415 10-01-2018, 01:55 PM
Last Post: Hemikiller
  1973 Mustang Coupe Exhaust System mustang7173 2 248 10-01-2018, 05:40 AM
Last Post: NOT A T5
  What externally will work on a 460 from a 351c scgamecock 15 520 09-29-2018, 01:57 PM
Last Post: 7173Vert
  71 vert dual exhaust, longtube header, 302 2V, reinforcement torque plate 1971V8 11 379 09-29-2018, 09:53 AM
Last Post: c9zx



Users browsing this thread: 1 Guest(s)