Toro 17-44 can't keep deck belt from coming off

Check you have correct belt for deck width, 48 or 54.


https://partscatalog.deere.com/jdrc/navigation/equipment/57472/level/2/snp/MTgyOTUyOkNIQVBURVJbMTA2MTojQlVTSU5FU1NfUkVHSU9OLDU4MDY6I0NBVEFMT0csNTc0NzI6RVFVSVBNRU5UXQ

something is grabbing and tightening the belt as you raise it. Look to see if the belt is routed correctly and what can be pulling of pushing the Belt to engage it

Engine off
I would check the tension, still taught?
Anything caught in mower blades? Causing a locked deck?
Your belt worn out is most likely if none above.
PTO Clutch possibly bad. Runs for a second(turns blades) then throws belt. Good luck.

I would remove the deck and belt, then spin each blade to isolate the loud noise. Also, make sure the blades are not bent hitting the deck. I always balance my blades after sharpening as well. By isolating the bearings spinning them one at a time, this will tell you where your problem lies. Hope this helps!

I’m happy to assist further over the phone at https://www.6ya.com/expert/layne_0fccff498c319c32

Is something Jammed into the Blade?

Sounds like a broken shear pin in the drive pulley. Check the belts and see if they are slipping. Broken shear pin will not let the blades spin under pressure. .

check for play in the bearings blade bearings and the idler pulleys

Check the belt on top of the mower deck. Make sure the belt didn't slip off or break.

im no expert but had a similar problem with an old craftsman mower. the belt keeper which is an L shaped piece of hardware located at the back of the deck next to the idler pulley spindal. Also could be the deck is cockeyed and needs to be leveled or the wrong v-belt.

For removing/replacing the deck belt, the general method is:

1. turn off engine, remove key and set parking brake
2. disengage blade by putting blade engage lever into off (disengaged) position
3. lower the cutting deck to the lowest position (closest to the ground)
4. relieve the belt tension (depending on the model, use a 3/8 inch ratchet set to tighten in the square hole of the idler bracket)
5. remove and replace the belt

NOTE: it's not necessary to completely remove the cutting deck.

Useful diagrams for removing the cutting deck, http://216.213.143.2/ProAuthor/ManProc.cfm?ManualID=425&ProcID=14794

For deck belt diagrams, http://216.213.143.2/ProAuthor/ManProc.cfm?ManualID=425&ProcID=14796

If the transmission drive belt needs to be replaced, several components must be removed and special tools (i.e. air/impact wrench) used in order to change the tractor's transmission drive belt. See an Authorized Toro Service Dealer to have your drive belt replaced.