Help with batteries and their positioning

[lugoismad]

I have a 14 foot v-hull boat with a 25hp electric start Johnson on the back.

Trying to figure out the best battery arrangement.

I have a large deep cycle battery thats less than a year old that came with my camper. We never camp anywhere without electric hookup, so I can easily switch the camper over to use a lawn mower battery to run the run away brake switch and have the big deep cycle for my boat.


I have a 55lb thrust bow mount trolling motor for the boat as well.

The boat will start just fine off a lawn mower battery.

I'm trying to decide between....

Mounting the big deep cycle roughly amidships centered in the middle and in front of the driver seat to even out the weight, and extending both the trolling and Johnson starter motor wires to reach it. I have a 100 foot roll of 4 gauge wire sitting in my garage so this wouldn't be difficult.

OR...

I can put a lawn mower battery in the back to start the 25hp Johnson with, and put the deep cycle up front as far as possible to help even out the weight, and not have to cut up and extend any wires. This way even if I wear my deep cycle all the way down trolling, I can still start the motor (or I can pull start it, so its not THAT big of a concern)

OR

I can put the deep cycle all the way up front, hook the trolling motor up to it there, and extend the starter motor wires to the front.


What would you do?

Edit - something I should add. I'm 6'4" and 300lbs, and will be using the boat both alone, and with my wife and kids. The drivers seat is mounted on the back bench, on the side, not centered.

 

[Slough Runner]

Split them up. Have the deep cycle up front. The closer to the trolling motor the better. The longer the run for wire the more you lose in amps. It's a good idea to keep the two batteries separate like your last option. Never fun pull starting your motor if you drain your battery. Just make sure the deep cycle upfront is mounted well. Good luck.

 

[duckfish]

Split them up. Have the deep cycle up front. The closer to the trolling motor the better. The longer the run for wire the more you lose in amps. It's a good idea to keep the two batteries separate like your last option. Never fun pull starting your motor if you drain your battery. Just make sure the deep cycle upfront is mounted well. Good luck.

^^^ This. I've always believed in keeping all main wire runs (and fuel lines) as short and accessible as possible.
Previous 2 boats the first thing I did was move my trolling motor batteries as far towards the bow as I could make a suitable mounting bracket. Haven't done it to the current boat yet, but I'll get around to it.