I use a 8" adjustable (Cresent) wrench. On the TT PRO 46, I wouldn't tighten it as tight as I could get it with that wrench. But I would give it a pretty good pull until it seemed I had all the squeeze taken out of it.

A 4 stroke is another matter. They sometimes backfire and try to kick the prop off.

With the LT40 spinner, it would be rather normal for the crank to only extend 1/8" beyond the nut.

Where did the bolt come from???

Enjoy,

Jim