Agreed, that was in essence my point, it should be a slight amount. When the prop is tight, the inner race of front bearing is sandwiched tight against the shoulder on the crank so any endplay on the crank is what ever play is in the bearing which should be slight.

If the prop was loosened, being that the ax doesn't use a collet on the drive hub, (just has a flatside on the crank), that would allow the crank to slide back & rub against the back plate. That's why I was trying to find out if the original poster had the prop off when he noticed excessive play & rubbing. If so, that would be normal.

If prop was tight & crank was still rubbing on backplate, that would indicate perhaps the thrust washer is missing?

-rep

Drube- just make sure you have #10 (in the pic) in your engine.