4. When returning to the dock, don't immediately turn off the generator. Instead, shut down systems and allow the generator a five- to 10-minute cool-down period with no load. "It just adds to the durability and longevity of the genset," explains Grady White's Jim Hardin. When the generator is shut down, close its intake seacock to prevent water from being forced up into the cooling system should you head out again.