On the San Juan, the transom is pretty small and an outboard on the stock motor mount has the potential to chew up the rudder with the prop as the prop sticks out past the cavitation plate. I got a plastic polyethylene cutting board from Wally World for $3.50 or so and cut it with my jigsaw, then drilled it and mounted to the cavitation plate with 2 – SS 10/24 x 1/2″ screws with locking nuts. Voila’ no more chewed up rudder… If you have this problem you can fix it this way.

Top view of Rudder saver attached to outboard

Side view of cavitation plate with rudder saver installed