"Morgans" wrote in message
...

Some instances I have heard of do keep a "radiator", but it usually is a
water to water heat exchanger. Seems it was a big commercial rig. It has
the advantage of not having salt water running through the engine.
Disadvantages are more complexity, and more to fail. You have to have a
pump to move that seawater to the exchanger, too.

My 19' skiboat had FWC (Fresh Water Cooling) using a heat exchanger. They
are fairly common on the coasts where salt water operation is a fact of
life. If it's in an inboard/outboard installation, the outboard unit has the
pump. If it's strictly inboard, there'll be an extra pump driven off the
accessory belt, the back of the alternator or some other rotating accessory.
The normal engine water pump circulates the engine coolant.

Rich S.