B2650 exhaust pipe and muffler cracking

nbryan

Well-known member

Equipment
B2650 BH77 LA534 54" ssqa Forks B2782B BB1560 Woods M5-4 MaxxHaul 50039
Jan 3, 2019
1,161
705
113
Hadashville, Manitoba, Canada
My exhaust pipe got cracked somehow just below the lower mount point, I guess I hit something, so having it brazed at a neighbor. But when pushing the repaired pipe back onto the muffler I saw the pictured crack at the muffler joiner flange. It was invisible with tail pipe mounted. I'm wondering if anyone has seen this kind of cracking on their B2650 mufflers? Vibration and minimal weld strength/thin metal the culprit?
Thanks for any feedback.


Sent from my Moto G (5) Plus using Tapatalk
 

whitetiger

Moderator
Staff member

Equipment
Kubota tech..BX2370, RCK60, B7100HST, RTV900 w plow, Ford 1100 FWA
Nov 20, 2011
2,542
1,059
113
Kansas City, KS
It's pretty common on B series, although its usually on the inlet side of the muffler.
 

nbryan

Well-known member

Equipment
B2650 BH77 LA534 54" ssqa Forks B2782B BB1560 Woods M5-4 MaxxHaul 50039
Jan 3, 2019
1,161
705
113
Hadashville, Manitoba, Canada
It's pretty common on B series, although its usually on the inlet side of the muffler.
Thanks for the feedback. But common with just under 200 hours on the tractor? I probably messed it up when whatever cracked the tail pipe outside the engine cowling, but it cracked right below its frame mount, which makes sense. But could there have been that much effect up where it joins the muffler? I guess maybe, but it didn't take much.

Sent from my Moto G (5) Plus using Tapatalk
 

Mondo

Member

Equipment
L355ss, back blade, bush hog
Apr 17, 2017
104
5
18
NYS
had a similar problem on my L355SS but it was in front of the muffler. JB Weld did a heck of a job. Still good after 2 years
 

whitetiger

Moderator
Staff member

Equipment
Kubota tech..BX2370, RCK60, B7100HST, RTV900 w plow, Ford 1100 FWA
Nov 20, 2011
2,542
1,059
113
Kansas City, KS
I have never seen one cracked at 200 hours but if you hit something, they can break at any time. Usually, the ones I see cracked are around 1000 hours or more.
 

200mph

Well-known member

Equipment
L4740-3 Cab, FEL, Fnt Snow Blower L2185, LP Finish Mower, LP Rotary Mower
Mar 3, 2017
1,228
58
48
PA
Looks like poor welding/manufacturing processes. If its a common failure as the above post suggests, recommend repairing versus purchasing a new one for $370. Why repeat the same failure?

I'm guessing you didn't do anything to cause the broken joint and the quality and/or design is a bit suspect. (Assuming it's common failure across other users).
 

nbryan

Well-known member

Equipment
B2650 BH77 LA534 54" ssqa Forks B2782B BB1560 Woods M5-4 MaxxHaul 50039
Jan 3, 2019
1,161
705
113
Hadashville, Manitoba, Canada
Thanks for all the feedback. The metal is too thin for a weld so went with brazing both cracks, holding fine so far after a day's this and that on the machine. And $370 for a muffler? USD? If USD then well over $400 CAD, it seems anything oem with these units costs a fortune, and in the case of the muffler, not very well made. Too Bad. But worth the sixty bucks for the fix at the neighbors, as long as it holds, of course!
 

200mph

Well-known member

Equipment
L4740-3 Cab, FEL, Fnt Snow Blower L2185, LP Finish Mower, LP Rotary Mower
Mar 3, 2017
1,228
58
48
PA
Yes, US dollars.
 

SidecarFlip

Banned

Equipment
M9000HDCC3, M9000HD, Kubota GS850 Sidekick
Oct 28, 2018
7,197
546
83
USA
I'd imagine the 3 cylinder engines shake a bit and various rpm's I know my turbo charged 4's in the M's have balancer shafts inside, not sure about the 3 cylinder engines.

When they shake, welds break.
 

nbryan

Well-known member

Equipment
B2650 BH77 LA534 54" ssqa Forks B2782B BB1560 Woods M5-4 MaxxHaul 50039
Jan 3, 2019
1,161
705
113
Hadashville, Manitoba, Canada
I'd imagine the 3 cylinder engines shake a bit and various rpm's I know my turbo charged 4's in the M's have balancer shafts inside, not sure about the 3 cylinder engines.



When they shake, welds break.
As the muffler and exhaust pipe are solidly connected through to the engine I have no doubt the engine vibrates them heavily against their mounts. An option might be to have a short section of flex exhaust pipe between the muffler and exhaust pipe, and/or a rubber hanger or anti-vibration mount for the outlet end of the pipe. Very custom, maybe unfeasible but I'll be keeping an eye on those braze repairs from now on.

Sent from my Moto G (5) Plus using Tapatalk
 

SidecarFlip

Banned

Equipment
M9000HDCC3, M9000HD, Kubota GS850 Sidekick
Oct 28, 2018
7,197
546
83
USA
can you install insulating biscuits between the mounts and the muffler?
 

nbryan

Well-known member

Equipment
B2650 BH77 LA534 54" ssqa Forks B2782B BB1560 Woods M5-4 MaxxHaul 50039
Jan 3, 2019
1,161
705
113
Hadashville, Manitoba, Canada
can you install insulating biscuits between the mounts and the muffler?
If the issue continues I'm going to have to find a way to reduce vibration, some padding at the pipe mount plate would help, or a short section of flex pipe at the muffler outlet. A little tricky to source such adapters I'm sure.

Sent from my Moto G (5) Plus using Tapatalk
 

MikeyA

Member

Equipment
2016 B2650 FEL and 60"mmm,1998 B2400 MMM FEL(sold!) BB 4ft BRUSH HOG
Mar 6, 2010
150
1
18
West Central Illinois
I noticed the same thing with my exhaust pipe last night. I have 275 hours on mine. A few minutes with mig welder had me back in business, but I am going to take a closer look at muffler in a few...
 

PaulL

Well-known member

Equipment
B2601
Jul 17, 2017
2,098
1,106
113
NZ
I'd imagine the 3 cylinder engines shake a bit and various rpm's I know my turbo charged 4's in the M's have balancer shafts inside, not sure about the 3 cylinder engines.
I thought the primary balance of 3 cylinder engines was better - i.e. less vibration than a 4. Still a diesel though.
 
  • Like
Reactions: 1 user

tempforce

Member

Equipment
B2650HSDC
Jun 23, 2012
389
2
18
bastrop, tx
another issue that hasn't been addressed. thermal expansion. the muffler and exhaust pipes, expand with heat. having the exhaust system solid mounted. puts stress on the weak points. so if your repairing the exhaust, i would suggest modifying the mounts to allow for the vibration and thermal expansion...
 

fj40dave

Well-known member
Lifetime Member

Equipment
B2650, LA534, BH77, TPD35, RCF2060, BB1566, RGA1258
Sep 24, 2009
417
254
63
Yelm, WA
I'll be fixing the muffler out-pipe weld on my B2650 tomorrow.
I'll get some pictures taken too!
Almost 600hrs on my '18
 
  • Like
Reactions: 1 user

fj40dave

Well-known member
Lifetime Member

Equipment
B2650, LA534, BH77, TPD35, RCF2060, BB1566, RGA1258
Sep 24, 2009
417
254
63
Yelm, WA
I fix mine today:

Welded up the exhaust and added a support as well!
20220429_112852.jpg
20220429_134947.jpg
20220429_134947.jpg



[/QUOTE]
 
  • Like
Reactions: 3 users