Fish Finder Fishfinder
Running nav. lights & fishfinder from 12v. battery.?
I have a 2005 manual (pull start) Mercury commercial outboard motor. Is there anyway I can charge a battery from this, not to run an elect. start on the motor but to run a fish-finder & nav. lights? Is it worth it or do the lights & fish-finder use so little power that I can run them straight off a pre-charged battery without worrying about the battery running dead? .
Some 20H.P. Mercurys have a small alternator built in to the engine. But, I think this is only electric start models. the output of these alternators is very small, particularly at low speeds. At say 3500 rpm the output is less that 5 amps. I think a Group 27 battery, would be a better use of your money. It would run lights and DF for several hours. Then you can recharge it. the Electric start kit,which includes the alternator cost several hundred dollars to retrofit to this engine. Good luck!
Humminbird Fish Finders and GPS Systems Summary