I have had a problem keeping my exhaust packing nut tight. I torque it down pretty good and tap on the wrench with a hammer. I've always just assumed maybe having 3 different metals (different expansion rates) could be part of the problem. The other day, while looking through the parts book, I didn't notice a muffler clamp on the stock muffler, which got me thinking, Maybe if the frame was designed to twist, the exhaust pipe was designed to "work" in the inlet of the muffler. Anybody else had this problem? It is stainless exhaust pipe with a steel stock Model T re-pop muffler with a clamp on the inlet, rigid mounted at rear muffler end cap. and never-seize on packing nut threads.

John

there's a reproduction of a period accessory which will hold the big brass exhaust nut from loosening up. Check major parts suppliers' catalogues.

You are correct John; You won't find a muffler clamp in the original parts books because Ford didn't use them. The exhaust pipe must be able to twist with the frame. If you use a clamp, then the stock muffler mounting must be abandoned in favor of a flexible hanger. Something must give when the frame flexes. Either the exhaust manifold, packing nut, exhaust pipe or the muffler bracket.

One other secret is to tighten the nut while it's hot. Might help.

Tightening up when it is hot worked - second time around - after going through a "new nut" that cracked across the flat when it cooled down the first time I tried it.

I do not have the muffler clamped to the frame, but the mounting bracket nut is locked with room to slide along the slot on the mounting bracket, this allows some twisting as well as expansion in the length of the pipe as it gets hot.

Cheers
Adrian

I made a rubber pad using a folded piece of an old rim flap, a cobbler punched a hole for the bolt for free, I put it between the muffler mount & frame to allow for movement. I've got a new stainless pipe with a packing packing nut & the repop "Lock That Nut" from Texas T in the garage, figure the next time, the packing nut falls off I'll put it on, I purchased it 3 years ago. If it ain't broke don't fix it.

Alex

Thanks every one of you. With your help I think I can solve the problem. You all confirmed my suspicions of what my problem is. I have an exhaust wrench that I carry with me but I found it hard to believe that everyone who owned a model T had to do the same.
John Berch

This is the ticket to solving your loose nuts...
http://www.texastparts.com/mm5/merchant.mvc?Screen=PROD&Store_Code=TTP&Product_Code=T3061-L&Category_Code=NewItems

A stainless steel hose clamp tightened up against the back of the nut works fine too.