Hi. I am new to the forum. Bought a used b2320 HST last fall . It had about 520 hrs. used it all winter with the snowblower worked fine. Put on the mower and mowed 2hrs parked it. when I went to move it bad noises from clutch, would not move.Split the tractor. Bellhousing was broke at top two studs. went to dealer for parts they checked and said a different dealer replaced bellhousing ect. at 492 hours. any idea what would cause two broken bellhousings