Muffler Replacement

[Don52]

The baffles on the muffler on my friend Rick’s tractor were shot, so it was very noisy. The original muffler had been welded to the exhaust pipe, so I cut through the weld of the old worn out muffler and welded on a new one. I like to weld the muffler to the pipe or a Nipple, because the threads of the muffler are in thin sheet metal and they crack off as shown in the following link.

https://forum.millerwelds.com/forum/...ohn#post598219

The first picture shows where I cut through the original weld. The weld looked like bird $hit, but it held up until the muffler wore out so I can’t complain.

1. Old Muffler


The new muffler had a 1” NPT thread on it and the pipe was ¾” nominal pipe size, so I screwed in a 1” NPT close nipple into the muffler to reduce the hole size as shown below.

2. Muffler with nipple

[Don52]

More to come.

[Don52]

Next I sawed off the nipple with about 1/16” protruding as shown below.

3. Muffler with cut down nipple


Unfortunately, I didn’t take a picture of the weld, but I welded the nipple to the muffler. Then I welded the muffler to the exhaust pipe as shown below.

4. Muffler welded to pipe


Last but not least I painted it. I didn’t bother to purchase high temperature paint so it will burn off the hot exhaust pipe, but the paint should still protect the muffler.

5. Muffler painted


-Don

[Hobbytime]

why didnt you just weld a threaded coupling onto the pipe so the next time it needs replacing you just unscrew the old and screw the new one on??

[Don52]

why didnt you just weld a threaded coupling onto the pipe so the next time it needs replacing you just unscrew the old and screw the new one on??

I wasn't sure if the tractor could accommodate the additional length of the coupler and nipple.
You will also notice that I welded the muffler crooked, just like the original, for the same reason.
I am familiar with the nipple approach and have used it in the past:

https://forum.millerwelds.com/forum/...ohn#post598219



-Don

[Hobbytime]

I wasn't sure if the tractor could accommodate the additional length of the coupler and nipple.
You will also notice that I welded the muffler crooked, just like the original, for the same reason.
I am familiar with the nipple approach and have used it in the past:

https://forum.millerwelds.com/forum/...ohn#post598219



-Don

I guess not having the unit the muffler goes on makes fitting it a bit difficult...better safe than sorry...nice repair either way...

[Don52]

On a previous repair, my customer didn't tighten the 1" NPT nipple properly into the exhaust pipe and the threads rattled around and wore out. Fortunately the nipple that I welded on was long enough to add additional threads. The first picture shows how I clamped the muffler to chase the 1" NPT threads deeper on the nipple.

11. Muffler clamped to table with 1 inch NPT die


The next picture shows my friend John manually chasing the threads with a home made die stock.

12. Chasing 1 inch NPT thread


The next picture shows the deeper threads. If you look closely, you can see that the original threads are undersize compared to the new ones.

13. Threads on nipple chased


The next picture shows me cutting off the damaged thread from the nipple on the muffler.

14. Cutting off damaged threads


And here it is all done.

15. Nipple cut down.


The moral of the story is if you use the welded on nipple approach, be sure to firmly tighten the muffler.

-Don

[Don52]

Here is a picture of the muffler installed on the tractor.



-Don

[Mikel_24]

Great save!

I usually have any kind of muffler work. Steel is paper thin, rusted, etc.

Mikel