Question about a dual purpose battery?

[njTom]

Does dual purpose mean you can use it for cranking and deep cycle trolling? I am looking at purchasing 2 optima batteries (D34M series) to replace the ones that came with my new boat (2000 Tracker Pro 165), one cranking and one deep cycle. In NJ most lakes are electric only so I will be using 2 trolling motors mostly, but will run the Mercury 40hp on my hometown lake and at my parents lake house in upstate NY a few times a year. I am trying to stay away from adding a third battery right now because of cost and I would want to upgrade the original onboard charger to a 3 bank and don't want to spend the extra money. Can I use a dual purpose battery for my trolling motor and to crank over my outboard? Any other opinions are welcomed.

Tom

 

[bAcKpAiN]

I have an Everstart 24 series dual purpose battery for my starting/accessory battery. I have an older motor that does not have an alternator so the drain on it is pretty big throughout the day. I fished a few tournaments last summer that had intense fog almost til noon so it meant my lights were on for a solid four hours plus. My livewell drain plug was leaking bad as well so I had to have the fill pump running comtinuosly as well. The battery started my 45 horse motor like a champ all day long right up until weigh in.

I know it isn't the same as a trolling motor running on the battery, but I think that would do you just fine. If I remember right my dual purpose actually had a higher reserve capacity than the equivilent deep cycles on the WalMart shelf.

 

[Butthead]

For what you're doing you should be fine with those.

 

[bajacoop]

If you are going to be using the trolling motor a lot I would get a dedicated deep cycle battery.