what does a heat exchanger do on a chevy inboard on a boat?
The heat exchanger uses raw water and circulates this water around in a tank filled with many brass tubes and then dumps this raw hot water into exhaust manifold and out. The FWC (fresh water cooled) coolant or anti-freeze is seperate and sealed from the raw water side. The coolant flows with the aid of the ciculation pump - thru the engine and then inside of the brass tubes - which in exchange - becomes cooler.
That set-up is normally for salt water boats. Saltwater in your engine manifolds shorten the life, become pluged corroded.The heat exchanger alows you to only have to replace a few parts from saltwater damage, instead of a lot of parts! almost a must have in saltwater conditions!!
Coolant from engine is circulated through a sealed system that uses ocean/lake/river water to cool it. This method allows antifreeze to be used in the engine vs outside water and doubles life of the engine.
A heat exchanger does exactly that. it kinda works like the radiator in a car. it keeps the engine cool.
