farmall bn exhaust

Anonymous-0 · Jun 4, 2013

Hi. My brother told me the other day that the BN seemed loud. I started it today and it is alot louder. I took the hood off to look at the manifold. It does have a crack in the exhaust portion but was not loud or leaking there. I looked through the muffler and it looked OK. It sounds different and much louder. Also isn't running real good now too. I figured it had to be muffler or manifold but they seem OK. Any ideas would be appreciated.
Thanks
Bob

Dave_Id · Jun 5, 2013

Did the 1 1/2 in npt pipe that the muffler is attached to get unthreaded from the manifold?

mkirsch · Jun 5, 2013

Running with the hood off, it should be obvious if there are any open holes or leaks causing it to be louder.

Otherwise, it HAS to be the muffler.

You said you looked "through" the muffler. That's probably your problem... If you can see through the muffler it's just a straight pipe that looks like a muffler and it will be LOUD.

The muffler probably had a baffle in the middle that rusted and blew out. If you'd looked before the tractor got loud, you probably couldn't see through the muffler.

As for it not running as good, that may just be the noise you're not used to. If it's really not running right, it has nothing to do with the muffler. Just a coincidence.

gene bender · Jun 5, 2013

New mufflers with the baffle run around 45 just make sure it has the baffle the 25 ones don't have the baffle.

farmallboy15 · Jun 5, 2013

If it doesn't seem to be the muffler it could be that the timing is off. I had rewired my H a few years ago and when I was done it was a lot louder. I don't know if I bumped the distributor or what but the timing was off and that corrected it.

Anonymous-0 · Jun 5, 2013

Thank you for the information. I ran the tractor with the hood off and didn't really see anything. Seemed loud at the exhaust. When I looked through the muffler it didn't look like any sort of baffle had been there and rotted out. It is the same muffler as before that seemed more quiet. I can check the mag and see if it is loose or timing is off.
Thanks for your help. Bob

CNKS · Jun 5, 2013

The original mufflers did not have baffles, A through 450. The reproductions that Ken Updike has had made this year do not have baffles--I have 3 of them, they are not particularly loud. I imagine the one in question has something burned out that he hasn't seen. Some of the aftermarket and or Case/IH ones have baffles but the original and new exact reproductions are straight through. But the center pipe is perforated, I do not know what is between the pipe and the shell, if anything, but they are probably 2/3 quieter than an open exhaust. They have the original sound.

farmall bn exhaust

Anonymous-0

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Dave_Id

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mkirsch

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gene bender

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farmallboy15

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Anonymous-0

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CNKS

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