[Jaggin79]

This is my first post, so be gentle. I have a 78 Panther that has a strange exhaust issue. At idle everything looks good, however when I rev the engine, the muffler acts like it is going to blow off the manifold pipe. I have put all new springs (flange and muffler to the base plate underneath), and still have the problem. As far as I can tell, there is no blockage. I can blow air through the muffler, and there doesn't seem to be any restriction. Any suggestions would be greatly appreciated.

 

[kccats]

Could be a mouse house? Try removing the pipe and heat it up with a torch, and tap on it with a ruber mallet. See what comes out?

 

[RJ Gleason]

Yep, it is partially blocked.

 

[Jaggin79]

Thanks kccats and RJ. I'll give that a try.

 

[Jaggin79]

Well, I did one better. I roasted the muffler on an open fire for about an hour. Got a bit of carbon smoke out of it. Shook it every way possible and got nothing to fall out of it or rattle around. Still acts like it's blocked.

Hmmmmm.

 

[RJ Gleason]

Try poking in it with stiff wire through the outlet tip.