A n open-loop cooling system, also called raw water cooling, draws water directly from the body of water the boat is floating in, whether it's saltwater or freshwater. That water is pulled through ...

Open loop system: $10,000 to $30,000; Closed loop system: $25,000 and $30,000; Permit. The cost of the permits depends on your area and on the type of system.

Open-loop systems are fine for light use in clean water. For everyone else, closed-loop systems offer better protection, longer life, and fewer nightmares when something inevitably goes wrong.