Drive belt keeps falling on my 50 inch toro zero turn

Question edited for clarity, full 'make model (what it is)'.
Question moved from Cars and Trucks category to correct Toro.

In that scenario, the clutch jamming and locking up against something may be a possibility. If the clutch just jams it holds the blades on contact with the drive.

Worn pulleys, badly aligned pulleys, or sticky bearing are much more likely. There is lots of help here as this is a known issue.

https://www.google.com/search?q=Toro+timecutter+breaking+belts

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usually if the pins are pulled out that is the freewheel position. push them in to drive. if the trans locks in drive and it is hard to push it should be ready to mow. unless the drive belt is stretched or broken or a linkage is out of adjustment or broken.

http://www.partstree.com/parts/toro/mowers-zero-turn-lawn-mower/74631-toro-timecutter-ss-5000-zero-turn-mower-sn-314000001-314999999-2014/belt-and-pulley-assembly/

Give this link a try. Once you have the belt diagram, and the right belt, it has to fit.

look for a diagram on routing of belt on the mower deck

HI, I have a Cub Cadet 50" cut I had a similar problem and I had to change the spring on the idler pulley it had lost tension and replacing it solved my problem. Not familiar with your mower but if it has the same principles as mine you might want to try that.

look at the pulleys for play also how is the spring tension ?

did the belt break or fall off? are the trans release levers pulled out ?the ones you release to push it around

the drive belt pulley probably needs replacing or the belt popped off the pully

The belt can be measured by your local hardware/lawn care dealer or by reading the numbers on the belt itself. You will find that purchase price is likely to drop significantly by buying an aftermarket belt too!