Anode issues

[nicholson31]

For some reason my Prop shaft Anode continually becomes loose. The set screw remains tight with thread lock, the problem is with the anode deteriorating between the set screw and where it passes through the anode center. (Anode is mounted on the end of the prop shaft). I Put a new one on in June and replaced it in Aug. just hauled the boat for the winter and this one is close to the same condition. It can be heard vibrating when sailing.
Was not an issue last year, only thing different is I have moved to another spot at marina. Was thinking maybe more electrolysis activity, but why is it eating around the anode screw hole and not the rest of the anode??
3ym30 engine.
Anyone have similar issues and/or suggestions?

Terry

[azsailor12]

Not sure why, but you might try painting over the screw and local area with nail polish. It will prevent that area from deteriorating.