You should use a automatic charging relay if you are going to be using different batteries, or even one new and one old battery.

I run this one: http://www.bluesea.com/products/7610...12_24V_DC_120A

Jordan,

From what I see this would would be grounded and then a wire from each + battery terminal to to the separate terminals on the unit. Would this allow me to have the battery selector on both for charging purposes while running or even starting for that matter?

Thanks again.

Jed

I think that is the job the relay will do ...when running, both batteries are charging , even though you would have the battery switch on 1 or 2 .....the only reason you would run both is if you wanted to combine both batteries ....m

Offthefront

Are you sure of this? I was under the impression that with the factory isolator switch the boat would only run or charge whatever battery the switch was to. Meaning if switched to 1 it would start, run, and charge only battery 1 and same with 2 and same with both. This is why when starting I would start on either battery and switch to boat the charge both. When sitting on the hook I will switch to only one battery to preserve the other for starting only and then switch to both to charge both for the run home.

Thank you.

Jed

thats exactly how it works ...but your switch is a battery disconnect/selector switch .......I was referring to the Blue Sea charging relay Jordon is referring to ....it will allow both batteries to charge when running no matter what battery your running off of .....You select either 1 or 2 and forget it .....if you do a lot of overnighters and sandbar stuff I would add a 3rd battery ....if you forget to run "all" one battery is not charged if you forget to take it off of "all" you can drain both batteries .........I've had good luck with the ProSport chargers ....m

If you run an isolator connected to the alt output ,it doesn't matter where your battery selector is positioned, both batteries will charge

So if I am understanding this correctly I would wire this directly from my alternator (versus the alternator going to the switch to charge the batteries) and then to the batteries so it will charge both whenever the mototr is running and the switch will decide which battery I am running everything else off of?

Correct ,from alt to isolator, then the outputs split and run to the individual batteries. Nothing to do with the selector switch. To keep it clean you can hook the charge wires from isolator to the 1 and 2 post on back of selector. Keeps it neater at batteries.

Thats a really good idea with the outputs on the selector posts. So now the slector switch is only for if I want the house battery or if I want the cranking battery?