My prop also sometimes turns slowly while in neutral. It's very slow. And I have a dripless shaft seal that uses water to cool it -- so no groaning.

wspeedin -- For the coupler, this just came up in another thread, but the easiest way to do it is to put a socket over the end of the shaft and then bolt it up to the transmission so that the socket "pushes" the shaft out of the coupler. You may need to use longer bolts to make this work and for the love of god, make sure you've pulled out any set screws before you try!