Raw water isolator for watercraft

A raw water isolator apparatus comprising:

• a storage tank forming a chamber therein for receipt of an admixture, said chamber having a chamber inlet and a chamber outlet;
• an expansion tank fluidly coupled to said chamber, said expansion tank constructed and arranged to maintain a constant pressure in the chamber;
• a pressure reducing valve positioned between said chamber and said expansion tank;
• a backflow preventer positioned between said pressure reducing valve and said expansion tank;
• a recirculation pump having an suction inlet fluidly coupled to said chamber outlet and a discharge outlet;
• a supply manifold fluidly coupled to said pump discharge outlet, said supply manifold having individual lines fluidly coupled to heat exchanger inlets located on each system that requires cooling on a watercraft;
• a supply return collector fluidly coupled to return outlets on each said system;
• a heat exchanger having a parallel plate with a first side for passing the admixture from the supply return collector to said chamber, and a second side for passing raw water;
• and
• a transfer pump directing a flow of raw water through said second side of said heat exchanger.