F25 mast upper bearing damage:

during the season the mast never rotated properly, and got some times would be very hard to rotate. I did a full upper and lower bearing service last winter, but this is what I found when I pulled the rig this fall

as you can see the sleeve which stays in the boat and hold the upper bearing and keeps water out of the cabin got wedged on the mast and needed to be cut out of boat in order to pull the mast.

*note: look to see how the mast is wedged to the left side of the tube, the upper bearing shifted causing it to get wedged

this is the upper mast bearing, as you can see it got pulled out of it's slot in the tube and from the pic below it forced the stainless bearing on the mast to be moved as well.

*note: my guess is that during the mast install the alignment got off and the to parts of the upper bearing where not true and over time they worked each other in to a pickle... luckly their is not real damage and can be easily fixed this winter.

you can see how the stainless ring on the mast which is the inner part of the bearing assembly was forced up and off its perch, which was part of the problem.