It is not trying to mesh with the transmission. Sounds to me like the splines do not line up with the splines in the hydraulic pump. Tke the PTO shaft at the back and apply a little pressure to the PTO clutch pressure plate and rotate the shaft and pull back on it at the same time. This will help inter the PTO drive shaft splines in the hydraulic pump. If you do not have hydraulics then the only places it would hang up is the support bearing bushing. Then take the transmission cover off and see what you need to do like get a file out. More questions? J.