Quote Originally Posted by southeast_iowa_guy View Post
Will have to check can’t remember. I know trolling batteries are series 31 and I think other two are 24 series. Trolling are 2 years old but no idea on 24 series they were in boat when I got it almost 3 years ago

Correct me if I'm wrong, but ....
I'm thinking the two 24's are hooked in parallel to provide the necessary 1000CCA for the big motor, and all the accessories are running off them, too.

My next question would be : what exactly is happening that you feel the need to "upgrade" batteries ??

Also ... I would hope that your 4bank charger has 10amps per bank, so as to charge the batteries fast/hard enough to knock off the lead plate sulfation.