Re: propeller shaft broken
On almost any outboard prop shaft, the weakest point is usually the splines on which the dog clutch rides. Most of the time, it will break there. SOMETIMES, depending upon the nature of the break, the engine may still turn the prop. However, more damage will be done internally by continued running.
As stated above, if you can spin the prop while the engine is in forward gear, the shaft or gear teeth are most likely broken. However: the only certain way to know is to remove the shaft from the lower unit.
