Small Engine Troubleshooting Problems? Ask a Mechanic Now.
Welcome to JUST ANSWER small engines, let me try to help you !! I don't know it all, but maybe together we can get you a satisfactory answer!
Transmission is driven by belt from engine to the top of the transmission. Is the top belt turning when the clutch is released and the transmission is in neutral? Will the tractor roll in neutral? Has either of the rear heels been off the tractor?
Have you raised the rear of the unit and checked each rear axle, to see if the axle can be spinning in the wheel from a sheared axle key? If belt is driving the transmission, and this is the geared transmission, it can have sheared axle key, or the input pulley may not be turning the input shaft. It splines on the input shaft.
see question is still open, did you find problem?