Broke mower belt

fatjay

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Kubota B8200, B7200, ZD21
Nov 12, 2016
303
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43
Eastern PA, USA
The belt on my 3pt finish mower broke today. It's not a kubota mower. I laid out the belt on the ground and measured it and got 110". That should be 110" OD, right?

Also 110" belts are expensive, except this one site I found. $7 for regular, $18 for kevlar. Amazon has them for $50 for regular. Soon as I can figure out the right size I'm buying two.
 

North Idaho Wolfman

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Jun 9, 2013
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Sandpoint, ID
If you ran the mower with the belt hopping and snapping like it was in your video, it won't hold up no matter what belt you use.
You have either a spring, pulley, spindle, or blade issue.
 

fatjay

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Kubota B8200, B7200, ZD21
Nov 12, 2016
303
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43
Eastern PA, USA
If you ran the mower with the belt hopping and snapping like it was in your video, it won't hold up no matter what belt you use.
You have either a spring, pulley, spindle, or blade issue.
I fixed that. The spring was wrong so there wasn't enough tension on it. The belt had been on there without moving for what was probably a few years, and was dry-rotted and had those bends ingrained into it. There were also bits missing that had fallen off.
 

North Idaho Wolfman

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I fixed that. The spring was wrong so there wasn't enough tension on it. The belt had been on there without moving for what was probably a few years, and was dry-rotted and had those bends ingrained into it. There were also bits missing that had fallen off.
Got it, so it was due for a new belt anyways.
Here is a good write up on belts:
http://www.vbelts4less.com/Measuring-Belts_ep_46.html
 

fatjay

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Kubota B8200, B7200, ZD21
Nov 12, 2016
303
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43
Eastern PA, USA
The belt was like new. It'd just been put on a while ago and sat there with tension on it and dry rotted pretty well. I was hoping the bends would smooth out and it would go around easier, but even with a higher tension spring it still bounced a bit. It came off once today and I noticed chunks missing after running for about 30min.

The spindles have no play, everything's lined up well, the blades are all in good shape. My front lawn looks amazing.
 

Tooljunkie

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May 13, 2014
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Went through the identical problem with a friends mower last year. There was no aparrent reason that would cause belt to bounce. So replaced belt. Old belt had a couple burned spots and every pulley it crossed caused the tensioner to jump. 1- buy the kevlar. 2- buy it local, you get it wrong and you are waiting on a correct belt and then you have to return wrong one.
 

fatjay

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Kubota B8200, B7200, ZD21
Nov 12, 2016
303
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43
Eastern PA, USA
I would love to get it local, but that seems to be not happening. Every moron I call says "what's your model number". No one knows how to look at a belt length. When I say it's x brand they say "oh sorry we only carry deere parts, goodbye" or cub cadet parts or what ever. They're idiot clerks completely incapable of thinking outside the box.

I found this one: https://www.gprindustrial.com/en/2132-b-section-kevlar-v-belts/16694-b107k-kevlar-v-belt-type-b.html

They seem to have every possible belt size/widthheight combination. Measured laying flat 110" would be outside diameter. The width I got when I measured was 5/8", height was about 1/2".
 

D2Cat

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I believe the belt number is the dimension inside the belt. The width of the belt on the back side is the: A,B,C,D dimension. You get to guess the length it stretched if you don't have the original belt number.

https://ma.juii.net/blog/v-belt-specs (with a German flavor)
 
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fatjay

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Kubota B8200, B7200, ZD21
Nov 12, 2016
303
129
43
Eastern PA, USA
The original belt was in good shape and pretty much unused, so I don't think it stretched much. It's length when I measured was exactly 110", no fractions at all. I think it just died due to age, or poor chinese quality, since it is a chinese deck. The only thing in english says "Benye Rotary Mower". The belt looks generic, so it could be original. It doesn't look like it has many hours on it, there's pretty much no wear on it aside from the dryrotted tires, which again, could easily be age and not actual use.
 

Bulldog777

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L3200, RTA1266, Modern 5' BB, Mustang 60 FM
Jan 25, 2017
215
0
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Texas
I went to a local shop to get a 108" belt. The clerk gave me a 4L105 and said it was the same length as a 108. I argued a little, but decided to try it..... It was returned due to being 3 " too short. Coming out of the HVAC trade, I'm familiar with belts. Like was said previously, they wanted a model and serial number. He frowned when I handed him the old belt with no markings. LOL. Now days, if it isn't in a computer, you're almost out of luck.

Sent from my SPH-L720 using Tapatalk
 

Daren Todd

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He frowned when I handed him the old belt with no markings. LOL. Now days, if it isn't in a computer, you're almost out of luck.

Sent from my SPH-L720 using Tapatalk
Get that quite often. :rolleyes: Usually gotta direct the kid to the end case with the belt measuring tool with the gates part numbers :p Then I usually have to explain to them how to use it :)

Love it when the ask me for a make and model number for a starter solenoid. I usually just throw out some random make and model not knowing if they actually came with one. Wink at the manager, walk back to where they are kept, paw through a couple boxes till I find what I'm looking for. Then walk up front and hand the box to the clerk while they are still trying to find it on the computer :D
 

fatjay

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Equipment
Kubota B8200, B7200, ZD21
Nov 12, 2016
303
129
43
Eastern PA, USA
That's what I usually do, but over the years hte places have been less responsive to the "let me in the back to root through your stuff because i know it better than you" approach.

If my measurement is off, that's on me. Finding a belt locally in inch increments is tough, hopefully this place I tried works out. I ordered yesterday and it still shows as processing. I better get it by friday, no way should it take 2 days to put a belt in a box and drop it in the bin.
 

Tooljunkie

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L1501,home built carry all, mini plow blade.
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My good friend manages the parts store,his brother owns it, also my buddy. So i get free run of the place.i also worked there for many years before it sold. So i know my way around. Im even tied into computer system. Mind you i do spend a lot of dollars there so it stands to reason.
I need a belt, i grab a few and return what not fits. As far as parts go, i have it really good. Couldnt ask for better coffee-i mean service...
 

Donystoy

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LX2610HSDCC, B/H, Loader, plus numerous other attachments. B7200 sold
Dec 10, 2013
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Binbrook, Ontario
I just replaced the belt on my MMM yesterday with a proper Kubota belt. This after putting on two regular Gates industrial belts last year that just could not take the HP and torque. I got them from a wholesaler that I used before I retired from the industry.
The proper Kubota belt was a bit more costly than the Gates but should last longer considering that I got 30 years (limited use for first 25) out of the original. I use Gates on the hydro drive on my "green" riding mower that seems to work fine but is generally a constant load. A proper OEM belt for that one is 5x the cost.