Hey Woody, why do you change your impeller so often? I usually do mine every 2-3yrs, but have gone 4+when using it less than normal. Gearlube at least once a year.
Sometimes I run through lots of sand. I change it for peace of mind.
My biggest thing is changing out my water pump every 6 months to a year. The gear oil gets checked every so often. I run the carbs dry every time I use my boat. Thats pretty much it for me.