The nut is a standard thread. Lefty-loosy. If you just hold the prop, there is a chance (a GOOD chance) that the prop shaft will spin with the nut. This is due to both the neutral clutch drum, part #4, slipping in the clutch spring (not pictured) and the prop clutch discs, # 29 and 30, slipping. Note that there is a PACK of these, eight each. Only one each is shown in the photo. The idea of this pack is TO slip, taking the place of a shear pin. If you hit an under water object, the pack slips and then you keep on motoring. It is MEANT to slip. So, most of the time, you have have to take the gear case off and hold part #4 in a wood-jawed vise, like Dave said, before you can undo the prop nut. You just undo the screws and carefully lower the gear case, while turning the prop shaft. You turn the prop shaft in order to slightly relieve tension on the neutral clutch spring. This all sounds hard but it really isn’t, at all; at least on a fresh water engine.
After you do all this, and have the prop and clutch discs all cleaned up, you HAVE to have the neutral drum (part#4) in wood jaws, in order to set the amount of slip on the prop clutch pack. This is done by only tightening the prop nut to a certain point. So, you’re going to HAVE to have that gear case off, eventually, anyway….
Long live American manufacturing!
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