J2023 cracked muffler

[jdom84]

yeah... idle on a 3 cylinder diesel vibrates like crazy, they all do. Keep it around 1400 or higher when using it and it wont have as much vibration. Might not keep it from cracking but would probably go 1000 hours before cracks again? I would still add a support, Its what im going to do this winter when not so busy.

You dont need to run these diesel engines at high RPM to get work done, however they do like to be worked every once in a while. The s3l2 engine can handle anything you throw at it. Most industrial machines that use 3 cyl deisel engines like pump's and light towers/generators run at 1800-2000 RPM non-stop all day every day.

 

[Blstr88]

I run mine at 1500+ RPMs only, its never at <1500 RPMs and mine still cracked at less than 100 hours.

The mechanic that fixed it told me whats happening is the lower support bolt is loosening/backing out and when that lower support comes loose it allows excess vibration which = cracked muffler.

I havent done it yet (tractors back at the dealer yet again, forward axle seal was leaking) but Im planning to put some red loc-tite on the bolt that holds the lower mount of the muffler as well as just keep a better eye on it.

My replacement muffler appears to be exactly the same as well, doesnt seem built any differently. If it cracks in the future when its not under warranty I would try welding prior to replacing on my dime as well.

 

[melmark]

When I took mine apart the lower bolt was nice and tight, however when I cracked it loose it did "jump" a bit as if there was torque on the exhaust system. I have been running at a higher RPM since I read a year or so ago that it wasn't good to idle all of the time but the damage may have been started by then. Thanks for the replies guys, just wondering if anyone had found any tips or tricks that I could re-apply

 

[jdom84]

I was looking at the muffler a bit more yesterday and with the engine stopped, the muffler seems solid. If you hit it hard enough, you can feel a tiny bit of vibration in it. With the engine Idling it seems like its vibrating a bunch but its just the whole engine vibrating. I'm wondering if this failure is more related to heat, rather than just vibrations. I thought it was the vibration because my last tractor had a Mitsubishi 4cyl engine that didn't vibrate much at all and the muffler on that tractor didn't even have a second support, just bolted to the manifold.

 

[texascedar]

Jdom84, I have been thinking about the vibration angle and I can't help but believe that a proper weld should hold regardless of the amount of vibration.

 

[jdom84]

I don't think the weld is what is failing, from what I've seen of what others have posted, its the steel on the muffler can right next to the weld that has cracked. As melmark said... there apeared to be torque on the muffler when he loosened the second mount. Maybe the torqued system plus the thermal expansion of the steel is what is causing it to fail eventually.

 

[texascedar]

Ok, I remember now that you mentioned it. It was the steel that broke on mine. Thanks for the reminder.

 

[melmark]

I installed my brand new one yesterday. I plan to take the old one to get it welded for a spare.....I suspect that I will need it. After installing and starting the tractor I put my hand on the muffler before it got hot. My tractor idles near 1400rpm and it was vibrating a lot at the rpm. As soon as I increased the rpm to around 1500 or 1600 it felt a lot smoother. I never payed much attention to it before but I will be running my tractor around that "sweet spot" in the future.

Mark

 

[flyerdan]

I'd still recommend making a cradle out of some flat stock and using some round stock from the mounting plate to support the far end. The cradle would just need to be tacked to the muffler at the ends and a couple places in the middle. That would prevent any movement and direct harmonics back into the base, which looks to be quite substantial for the rest of the muffler.
Speaking of the 'sweet spot' some aircraft engine and propeller combinations have warning placards to avoid certain rpm ranges as they can develop damaging harmonics.

 

[Bill601]

I just had the second muffler break on my 2014 Boomer 24. I was going to replace it, but the bracket that hold the end of the exhaust pipe broke as well, so it's just going to keep happening.

I'm working through the idea of getting a U-shaped tube made and welded to the pipe that's still attached to the manifold and then connecting that to a muffler mounted somewhere on the tractor via flexible exhaust tubing. Anybody tried that?