The knotmeter stopped working mid-season on one of our old Catalina's, there was that plug so all I needed to do was a quick swap. It was a beautiful sunny day, I had the towels ready and finally got up the nerve to pull the paddle wheel..........it was mesmerizing, I could look through the hole and see the sunbeams going down through the water. It took a few seconds to realize that water was pouring in before I snapped out of it and got the plug into place.

Zebra mussels had built a little house in the paddle wheel. That was when one of the old timers told me to put marine trailer bearing grease on a q-tip and smear a light coat on all the surfaces. I have been doing that at the beginning of the season for a lot of years, never had an issue again.