Just bought a 7753 !! Unloading it off the trailer at home, I heard a pop …. and the right rear tire locked up. I finally got it in the shop, with help from the old tired 731. I jacked up the side, and put it on jack stands. Both tires seem to move with about the same amount of free play, but with machine running, only the front wheel has power to it …… I just want to know the best way to tackle this. Not sure where the chain case is on this machine. Thanks !!