Hello all,<br /> I own a 20ft. Pontoon w/an 83' Johnson 50 hp. w/4.5 amp charging system, I have a 12v Igloo cooler that I'd like to keep on the boat, but draws the same amps, 4.5amps!<br /> Is there a charging up-grade that I can install that will increase my charging out-put so I can run the engine, the cooler an keep the battery(s)(2) charged? 