Parallel Batteries

[flyman013]

I am thinking of running my trolling battery and starting battery in parallel next season. I plan on running wires from the trolling battery in the bow of the boat to the starter battery in the stern with a disconnect switch between so when I'm using the trolling motor, I won't suck down the starting battery. My question is A) will this give me more power when I run all of my electronics? At night when I have my nav lights, marine radio, GPS and fish finder on, I don't have enough power to run my music radio. At trolling speed, engine runs about 800 RPM so the alternator is not putting out at full capacity. If this will help, what gauge wire should I use?

Or, if anyone has suggestions on how I can get alittle more power so I can listen to tunes while trolling, I would greatly appreciated. Thanks.

[Lemon Chill]

We solved our electrical use at low RPM by using a smaller alternator pulley Most engines are designed to top out at 5 to 6 Grand but boats stop at about 35 hundred so there is room to change without Damage t the alternator .MBK

[1mainiac]

If the alt won't maintain the load you will just run down 2 batteries instaed of one. Most alt are geared to put out max power around 1500 so you may gain some with a smaller pulley my bet is you either need a bigger alt or a smaller load ie go to LED lights to reduce power needed. I am going to convert most of my lighting for night fishing to LED's this winter I found a deal on some LED spreader lights that draw about .6 amps ea instead of the 5 amps my current ones draw so I could run 16 of them and use less power than the 2 I currently have. I am going to install at least 4 lights a couple of LED back up lights for interior light and a couple of these spreader lights for the rest. Running the cable to your trolling motor battery would make for a nice backup and I would suggest 1/0 cable in case you ever need to start the boat with the trolling battery. One thing I have carried with me from time to time is a very small Honda generator even though I have not needed to use it it is nice to know I can.

[flyman013]

Thanks Jim. I was thinking about upgrading to LED lights for the bow and stern. I found some at Thefind.com It sounds like a good option.

[Nailer]

We solved our electrical use at low RPM by using a smaller alternator pulley Most engines are designed to top out at 5 to 6 Grand but boats stop at about 35 hundred so there is room to change without Damage t the alternator .MBK

Welcome aboard Michael.