Re: 1957 Evinrude Big Twin 35 flywheel keyway

[frankr]

Searching my brain for the two marks you are asking about. If you mean on the side of the key, next to the curve, those are there to make it fit tightly in the crankshaft keyway. In other words, you almost have to hammer it into the keyway. Now what’s this about one way, taper? Maybe I don’t understand your question.