Dan Best wrote:

Good points, especially the clogging with salt. I also like your idea
of possibly collecting the water that condenses out for reuse.

Instead of putting the radiator underwater and running air pipes down,
it might me just as effective and easier to keep the radiator on board
and drop a flexible hose with a weight on it to pick up the cooler water
at the bottom.

Yes, but then you need to pump sea water in addition to
moving air. KISS suggests that fewer pumps use less power.

I know, I know, a 'bilge pump' would be required to remove condensed
water inside the heat exchanger used below the water, but the amount
of water would be less, and fresh water doesn't promote fouling
inside the water lines. 6:1/2dozen?

If you used a deeper pickup for cooler water, the discharge should
also be below water, using the syphon effect to reduce the power
needed to raise the water from the deep to effectively only that
required to overcome friction inside the pipes and temperature
difference density * head, far less than that required for raising
water above the surface to be discharged above the waterline.

Ducting might allow an engine compartment blower to be double dutied
as cooling ventilator if the chimney doesn't produce enough airflow,
or if sealing the cabin to control airflow is undesirable. My engine
blower sucks a little air from the cabin as is, and would do better
if ducting arrangements closed the normal engine compartment air
intake line or switched it to a cabin air intake. I believe that
engine air intakes would be safer if they did not provide a direct
duct between cabin and engine compartment in the event of engine
fire or exhaust leak, while engine is running.

Additionally, cooler cabins under intense sun would result from
overhead insulation and shade arrangements.

-TK


Terry Spragg wrote:

Plumb an old car heater radiator...
Perhaps a few feet of plastic 3" pipe could push an air box down to
deeper, cooler water? Two such pipes could conduct air through the
radiator....
Evaporative coolers clog with salt if the water used is not fresh.