You'll need to remove the starter, clamp it in a big vise, and extend the gear by pushing the stomp linkage all the way into the "engaged" position. Clamp a pair of vise grips onto the gear teeth, firmly, but carefully so you don't break the teeth. Then connect some jumper cables to the starter hot terminal and ground (yes, there will be sparks!) If the drive unit is good, the armature will not turn- - - -disconnect the cables immediately. If the starter shaft spins, you've got a slippy drive unit.
Jerry
