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I have replaced O rings and even used some high temp gasket sealer and I still have a big leak up front.

Could pipe be tweaked enough that I am not getting a good seal? (FMF Gnarly BTW)

Some one told me that they have seen exhaust port on cylinder get worn...I find this hard to believe and hope its not the case for me.


Any help will be grateful.

are both springs on and providing good tension? Do you have a brass ring between pipe and cylinder ? I didn't even know there was supposed to be one until I got my last top end kit.
That being said, without the ring I had no leak there.. so perhaps you have a tweak, as you said.

Yes, I forgot to add that I put in new brass ring and springs.

Yes, the exhaiust port can get worn. Steel beats aluminum in an abrasion contest.

Also, yes, it could be a bent pipe not allowing it to seal properly. Beyond that, perhaps your other pipe mounts are bent / misaligned somehow.

Coat the pipe with Permatex Rt. Stuff before inserting into exhaust port.
That will also eliminate ANY wear of the steel pipe in an aluminum port.

This will dry like a hard rubber , I'm not a fan of truely hardening sealers for
this type of application , too much vibration.

C George wrote:Coat the pipe with Permatex RT

First post said he tried that

May be able to get a machine shop to put in a sleeve to get the exhaust port back to the right size

maybe it is jetted too rich as well as not sealing well at that juncture

KDXohio wrote:

C George wrote:Coat the pipe with Permatex RT

First post said he tried that

May be able to get a machine shop to put in a sleeve to get the exhaust port back to the right size

Permatex Rt. Stuff is a totally different animal than " high temp silicone "

Permatex Rt. Stuff is a totally different animal than " high temp silicone "

Are you talking about the red permatex rtv?

He said gasket sealer so im assuminghe meant the red or black permatex but i could also be wrong

Permatex Right Stuff gasket maker is what he is referring to.

I use Permatex copper sealant. It's meant for high temperatures. Says right on the tube suitable for exhaust components.

If your pipe or hangers are bent it won't seal well.

The thing to do is check fit first. Put the pipe on, no silencer and no sealent and make sure it is square in the cylinder. The pipe hangers get tweaked and when you hook them up it can pull the pipe out of square. Keep tweaking on the hangers until the pipe seats nice and is square with the cylinder, THEN take it back off and apply the Permatex. Let it set up overnight and then see how the silencer fits. It is easy enough to bend the length of pipe coming out of the silencer so that it does not pull the pipe when mounted.