Cub Cadet LTX 1050 Deck Belt

StinkyB

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I have a 2011 Cub Cadet LTX 1050KW, I have been having problems with it breaking deck belts. The belt just breaks as if it were cut, not worn or shredded, I am on my third belt this season, and at $50.00 a belt it is frustrating. I have read post about this mower breaking , and throwing belts frequently, I was wondering if it could be cutting the belt at the two idler pulleys when the belt gets thrown off, because there is a belt keeper that is very close to the edge of the pulley. You have to loosen the 2 pulleys to get the belt on. Has anyone with this mower had problems with it breaking belts, mine has about 225 hours on it, and it has been breaking belts since it was new(about 8 belts now), no one can find any problems with it , i am at my last wit with this one.
 

mechanic mark

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I had same problem with my simplicity, removed deck inspected everything, found problem by moving everything by hand checking for excessive play. 3/8" x 1 1/2 grade 5 bolt holding idler arms together was stretched & excessively loose, my son & I had to disassemble idler arm assembly to see bolt was culprit. We purchased a grade 8 bolt 2 & 1/2" long with shank having 1 and 1/2" no threads, bolt is 7/16" diameter with washers & self locking nut to fit. Had to drill deck & 2 brackets with 7/16" drill bit. Greased shank heavily upon installation because idler arms rotate on bolt shank when engaging & disengaging pto for blades. I will also say that most manufacturers use this same setup with 3/8" bolt holding idlers together on non commercial mower decks. This resolved my belts breaking on mower deck.
 

Pumper54

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I just replaced the deck belt on mine and I found that it was installed WRONG from the factory or by who ever set up the mower the first time. I had to remove the idler arm tension spring to get the old belt off. I could see where the belt was rubbing on the idler arm itself. Good grief what ever happened to pride in your workmanship?

Cub Cadet deck small.jpg if you look close you can see how the belt runs under the idler wheel bar

Tom
 
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Pumper54

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StinkyB,
Quick question for you, are you engaging the blades while the mower is in motion? The dealer we bought our 1050 from said doing that and/or adjusting the deck height with the blades engaged might throw the belt. When I mow I stop and engage the blades and preset the deck height. Just something to think about.
Tom
 

StinkyB

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Pumper54,

My deck looks like yours, except where yours has a wire belt keeper on the idler puller, mine has a metal tab that sticks up from below the pulley. Tried to mow yesterday and it broke a nother belt, got less than three mowings out of that belt!!!!!:mad:
 

possum

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Something is wrong. Take off the deck and find out what it is. Small list. Wrong belt. Lost spring. Spring hooked in wrong place. Wrong spring. Pulley bent or worn. Idler pulley bent, worn, bearing out. Spindle shaft bent. Spindle bearing out. Spindle tower loose on deck. Deck cracked . Deck bent, warped, sprung. Deck hardware bent, loose, broken, missing. Engine pulley loose, moved, bent, damaged. Engine loose on frame. Deck wheels binding up and sinking in on muddy soil. To fast on rough ground. Mowing through ditches. Start looking. Start turning. Start measuring. Start eyeballing.
 

StinkyB

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One question, if you look at the idler arm with the two pulleys on it from the side of the deck, should it be parallel to the top of the deck, or should the front of it angle down towards the deck?
 

cpurvis

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I have a 2011 Cub Cadet LTX 1050KW, I have been having problems with it breaking deck belts. The belt just breaks as if it were cut, not worn or shredded, I am on my third belt this season, and at $50.00 a belt it is frustrating. I have read post about this mower breaking , and throwing belts frequently, I was wondering if it could be cutting the belt at the two idler pulleys when the belt gets thrown off, because there is a belt keeper that is very close to the edge of the pulley. You have to loosen the 2 pulleys to get the belt on. Has anyone with this mower had problems with it breaking belts, mine has about 225 hours on it, and it has been breaking belts since it was new(about 8 belts now), no one can find any problems with it , i am at my last wit with this one.

Did you buy this mower used? If so, you may have found out why it was for sale.

When does it break the belt, when you engage the mower or just randomly, in the middle of a cut? Engaging the mower puts lots of stress on the belt and my advice on that is engage the mower at low engine speed, then add throttle. Also, get rid of the nanny-state, protect-me-from-me switches that disengage the mower.

Of course, if that's not when the belt breaks, that's not the problem. It's still good advice, though, and will also make your electric clutch last longer.

In the other case, where it breaks while running: It's hard for me to imagine how a belt can break and look like it was 'cut by a knife' unless it's running so loose that it can deviate from its normal path and contact something sharp. Make sure you have the belt as tight as the manufacturer recommends.

Also, if you're buying belts from Cub Cadet, you can probably save money by buying the belt at an auto parts store, like NAPA.

Good luck.
 

bertsmobile1

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Did you buy this mower used? If so, you may have found out why it was for sale.

When does it break the belt, when you engage the mower or just randomly, in the middle of a cut? Engaging the mower puts lots of stress on the belt and my advice on that is engage the mower at low engine speed, then add throttle. Also, get rid of the nanny-state, protect-me-from-me switches that disengage the mower.

Of course, if that's not when the belt breaks, that's not the problem. It's still good advice, though, and will also make your electric clutch last longer.

In the other case, where it breaks while running: It's hard for me to imagine how a belt can break and look like it was 'cut by a knife' unless it's running so loose that it can deviate from its normal path and contact something sharp. Make sure you have the belt as tight as the manufacturer recommends.

Also, if you're buying belts from Cub Cadet, you can probably save money by buying the belt at an auto parts store, like NAPA.

Good luck.

OEM & after market mower belts are Kevlar in neoprene
Auomotive belts are polyester in neoprene.

They are not and never will be the same, the kevlar is about 20 times stronger.

Pull the deck off. fit the belt as it would be on the mower, get on a ladder & take a photo of it.
Also take a photo of the broken ends of the belt, top view , side view and face on the fracture.

Keepers rub on the belt and "keep it in the pulley when slack".
They should not be in contact with the belt when it is tight, if they are something is wrong with the keeper or the belt run.

It is impossible for a mower engine to apply enough tensile force to snap a deck belt, they simply do not have enough power.
What is happening is the belt is getting damaged in some way then the internal fracture get to a pont where the section size is not enough and then they appear to "just snap".
Most usual is wrong routing causing too much or too tight reverse bending which causes small splits in the neoprene fill under the cotton cover.
These grow till they are right down to the reinforcing fibres then the belt snaps.

Belts are a lot more complicated than most think and in many cases the only belt that will work is the manufacturers belt because they have a customised size & layout of reinforcing.
 
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