Hi all, I recently purchased a 1964 Wheel Horse 1054 and have been fixing it up. The tractor was working great but then crapped out while plowing snow. Runs in neutral but when I shift into gear the motor is stressed and kills; it will go in reverse. When up on a jack and drive belt off the wheels move freely and I can shift and wheels and flywheel move easily in unison. Once I put drive belt on and run tractor while on jack the tractor will not shift, just grinds gears and then motor cuts out. The gears look to be in pretty good shape. Any ideas?