A 60 watt bulb under the engine box will keep the bilge very dry and usually warm enough to not have to winterize. I leave mine on when the boat is hooked up to shore power and my engines look very clean and rust free with over 23 years of service. Of course if the temps drop way below 20* F for more than a couple of days then you might have to add a block heater to the motor to keep it warm enough unless the boat will be winterized.
Not sure what thread it was but someone recently post pics of an air chase he had added that let air in/out under the gunwale. Like a bump on the inside of the side of the boat that was open at the top but just under the side deck by an inch or 2.
I am thinking i might take one of these solar powered vents and set it up with a duct to constantly move some air from my bilge. Maybe even mount it on the side of the house? not sure how those are designed so vertical installation would probably not be best.
Seems like a relatively easy arrangement and I would rather have it ducted out than have the vent fan on or near the cockpit floor.
The lightbulb idea is good too but the bulbs can burn out and you need shore power. I like the idea of adding a little heat though.
I had 2 of those solar vents on my Grand Banks 42. One in the aft cabin blowing air IN, & one in the V Berth blowing air OUT. (Reverse blade on one) Worked great when on the hard or when boat was left unattended. Good positive air flow. Always wanted to add one to the bilge/engine room near the holding tank, but never got it done. Roy
I replaced the deck in my last boat and added air inlets in the stern corner where the side of the boat and transom meet that came up under they gunwale. So the engine drew air the length of the bilge. Bilges were always dry. Sorry no pics I dont own that boat anymore.
Many thanks for the replys.. What I was talking about was the ventilation system that CB posted.. I will be copying that thank you..the way that my stringer system was designed, there is no ventilation at all on the pockets outboard of the hull stringers and the way that the deck stringers are supported (a angled 2x8) ontop of the hull stringer I think it lead to failure of the deck stringers and the deck to some extent. I'm finding out that my boat was a kit boat. If you look at BillDs stringers which are in excellent shape being an '89 boat.. It makes a difference .. I know this cause my stringers are 2x4s and BillDs are 2x6s( the way terry built them