I hadn't used my Lazer Z XP (27HP diesel) with a 72" deck in about two months and started it up last weekend just to mulch some leaves. I keep it out of the weather under cover in a garage. After normal start up, when I engaged the mower blades, there was a puff of smoke and one of my mule blades snapped. I think the the smoke was from the blade snapping -- one belt was shredded where it broke and the other belt was twisted but still on the pulleys. I think when the first belt snapped, it fouled the other belt. The deck, blades and mower belt was clean and free (didn't see nay rat guts either!). I had less than 6 months and 70 hours on the mower and belts. Just to be on the safe side, I bought two new Exmark OEM mule belts (PN EXM103-0881) so I could change both at the same time. Before I change out both mule belts, do you have any ideas as to what would cause a relatively new, and otherwise good belt, to snap when it was engaged? The only thing I could possibly think of was that maybe the belt was stuck to a pulley from sitting or because I rinces the mower off before putting it away. I usually blow off the grass and rinse it but have never had any problems like this. Should I send the belt to the dealer or Exmark to look at?