This message is a reply to an archived post by dan newberry on November 17, 2016 at 13:14:37.
The original subject was "Re: x320 John Deere throwing drive belt".
Just an update for future forum searchers...
The reason the drive belt comes off the x320 JD mower is... the parking brake releases a *lot* of tension off the drive belt, and with the engine at higher rpm's, the pulley just sheds the belt (at the engine).
To prevent this from happening shut the engine off *before* mashing in the parking brake. You do have to press the parking brake before starting the tractor, but of course the rpm's won't be at max, so there shouldn't be an issue there.
In any event, the belt throwing problem is not the belt itself, and it's not the belt guides. We installed a new belt from the John Deere dealer, and inspected and ensured that every one of the belt guides was properly in place and adjusted, and pulleys were not bent or knicked.
It's the parking brake... shutting the engine off at high rpm after locking that parking brake has the propensity to throw the drive belt.
I hope this helps others avoid this pain in the neck issue. :o :)