Hi Brian,
Hmm, I have had quite a lot of experience with different boat engines, their associated gearboxes and plant machinery in general, I served in the Royal Engineers for 22 years. To my mind, if something ain’t broken, don’t fix it, just monitor the situation. I always put my gearbox in reverse when the engine isn’t running to prevent the propeller from spinning, negating the cbance of fouling stray ropes and stopping any noise!
Hope you are enjoying the southern summer, happy motoring.
Regards, Lawrence