I have a cockpit drain lines that run down to through hull fittings. If I did not follow the 'what can go wrong, will go wrong' mentality, I would always leave the cockpit drain line through hull valves open, to allow rain water drainage from the cockpit.
I am just concerned about leaving a through hull in the open position while I am away from the boat.
I have a bilge pump hooked up through a float switch, but the breaker switch needs to be turned on in order for it to work.
My question is: Do other members leave their through hull valves in the open position?