Ordered new muffler and steel exhaust pipe assembly for my 1926 roadster.
Upon installation, noticed that the exhaust pipe was touching at the hogshead and rear running board bracket. In addition, the front of the muffler was contacting the frame. After a search of this forum, found that this is a common problem with reproduction exhaust pipes.
Got out the dead blow hammer, a block of wood an improvised mandrel in a vise to stick in the end of the pipe and went to work. After installing, removing, adjusting and reinstalling a number of times, was able to get it to fit with ample clearance. One thing I noticed was that a small bend adjustment makes a considerable difference in the clearances. Pen marks on pipe indicate where exh. pipe was modified to fit.
Bob, you should not need the clamp on the front of the muffler. The pipe should be free to move at the join so there are no stresses in the system during heating and cooling cycles.
Hope this helps,
Allan from down under.
Thanks for pointing that out Allan. Makes sense. I hadn't tightened it yet.
Indeed correct, in fact some hi-temp "copper" anti-seize between the pipe and muffler connection doesn't hurt in my opinion.
What do you expect from a reproduction?
Vern Campbell told me that a playing card should fit loosely between the pipe and hogshead.I have two of his ss pipes.
I'm about to install my new/reproduction pipe.
I plan on massaging it a tiny bit with a hammer where it touches the hogshead.
You can go ether way re the clamp on the muffler with pressed steel ends. In that case the original muffler/exhaust pipe was one piece all the way from the manifold to the the mount on the rear of the muffler. The muffler mounting tab flexes some to allow for expansion. The cast iron however is different, both ends of the muffler were mounted to the frame and the pipe has to have room to expand/contract so has to have a loose fit into the inlet.
The pipe should be fastened to the manifold before using any clamps or bolting on the muffler. It should be free and not forced into a position where there is pressure on it.
One reason it is hard to fit a new pipe is not because the bend is incorrect, but that the center of the frame is sagging, and or the ears on the crankcase are bent which will cause the engine to set at a different angle than original. So you must either straighten out the frame and engine supports or bend the pipe to fit in your particular situation.
Thanks to all who replied. This is great information on the Model T exhaust pipe system.
Hadn't considered that after 91 years the frame may be sagging or the ears on the crankcase may be bent.
The faithfully reproduced mandrel bent exhaust pipe featured in Steve's link looks real nice. Does anyone know if these are still available and from which vendor?
Larry Smith who was in the link that Steve posted made them. I don't know if he plans on making another run or not, but I think he should. I have one that I bought when he first made them. Haven't installed it yet, but I will. First class product!!!! Dave
You guys really are spoiled. Imagine trying to get the pipe out past the pedals on a RHD car! The pipe must kick outwards immediately it leaves the packnut. Then it has to find its way past the reverse pedal and downwards to miss the clutch linkage before it heads back towards the starter foot switch. It needs to clear that with a good margin before it can head out the back.
We had real problems getting pipes that fitted until I was able to deliver a complete driveable chassis to a custom exhaust maker. Now he has developed his own computer controlled bending pattern/jig/program and we have gone from a 1 in 10 fitting rate to 9 in 10 at first try. Our T club has them made as a service to members and as a club fund raiser on others we sell.
Allan from down under.