Craftsman deck exploding

[Craftsman Garage]

I was mowing after I had replaced the spindles, blades, and 1/3 idler pulleys ( they mowed freely and were in good condition and didn’t have replacements), engaged blades and the engine bogged a bit (even at high rpm) and the whole mower shook like crazy until it built up rpm, then it just shook a little bit. 10 seconds later, BANG from under deck. The belt had come off somewhere and caused a tangled mess and A keeper turned 180 degrees and bent, it looks like in the photo below. It is keeping the belt on an idler pulley. I’m clueless as to what caused both of these things to happen, maybe the belt is too small or is stretched. This is on a craftsman dgs6500 (2008 917.28848X) with a 54” deck with a Kohler courage sv-735-0016 26HP vtwin. TIA for help

 

[StarTech]

One problem that model number is coming with 48" deck spec'd. So apparently someone has swapped the decks or Sears has the wrong info.


So now we got figure off what the deck came from.

 

[ILENGINE]

The issue arises due to wear in various components both on the tractor and the deck which leads to that pulley being at too acute of an angle. When the deck is engaged the belt jumps from the sudden motion from the electric clutch engagement. Also on rough yards the belt can also start bouncing causing the same issue. That jump causes the belt to snag between the belt guide and the top of the pulley causing it to pull the guide out of place, jumping off of the pulley, and in some cases damages the belt. That issue has been seen several times over the years on the 54 inch decks used on the Husqvarna and the Craftsman mower they use to make.

 

[Forest#2]

I've noticed that:
As above and also any time a PTO is en-gauged and it does not sound right, like you mention, engine pulls down, you feel vibs in your cheeks in the seat, and it's getting worse, then stuff hits the fan, next time think about turning off the PTO before it gets worse because things usually do not get smoother.
I suspect the belt/belts was not routed correctly.

That also can be a dangerous thing to bystanders if a blade comes flying out.

Stay safe when inspecting.
You may have to completely remove the deck for inspection.

 

[Hammermechanicman]

I would bet lunch the belt was routed wrong around a belt keeper. Just sayin'

 

[StarTech]

Now I see where there is some confusion with vendors. Some idiot at Craftsman reuse the model number. It is list both for the 48" and 54" decks.

 

[SeniorCitizen]

If it has spring loaded idler to tension the belt i would think a belt installed wrong would be evident ?

 

[Craftsman Garage]

I’m pretty sure the belt is routed correctly. I did it twice the same way. Second time lasted a bit longer because I moved the keeper a little bit more towards the front of the mower. It’s the exact same setup as in the diagram below and I’m pretty sure the belt was routed as shown, but I’ll try a third time I guess. I will also take that keeper off and see if that fixes it.

 

[Craftsman Garage]

If it has spring loaded idler to tension the belt i would think a belt installed wrong would be evident ?

Yes it has a releasable handle connected to a spring that tensions it, will try to reroute belt again tomorrow.

 

[ILENGINE]

Most of that style deck from husqvarna has a hole in the idler arm where the bottom of that belt guide is suppose to fit into to help prevent it from turning Just be aware that if the belt catches that guide it will bend the guide and pull on from its hole.