Originally Posted by The Scarecrow
Oh off the top of my head I'd say you bent a shaft or prop.
As bad as you discribe it, you should be able to see it by rotating the prop by hand.
Look for two things, the shaft moving up and down as it rotates, and/or the prop blades not running in a straight line, viewed from the side.
I did check for both of these things, everything seems to be in order
Sorry for the bad explanation!