Went out to mow the yard for the first time at the begining of last week. Every time I went into reverse the drive belt popped of the hydro pully. Figured since it was the original belt to the tractor I replaced it with an oem belt #130969. Back out to cut again the day before yesterday and the same thing happened again. Plowed snow with it less then a month ago no issues. Looked it over real close yesterday and the new belt is routed correctly and thru all the keepers. Any suggestions are gladly welcomed.