how long will a 24 volt motor last on the water?? i know it will last longer than a 12 volt motor but im not sure how much longer. i would like to be able to fish a 12 hour day non-stop. will a 24 volt motor allow this?

What kind of boat are you fishing out of?

a 14 foot modified jon boat.

i had a 12 volt that lasted 8 hrs in a 14 ft modified jon.

it all depends on boat weight, wind, current, time foor is on the trolling motor. I doubt the whole 12 hours your foot will be on the trolling motor, my old 12 volt kept me going 12 hour days all the time just keep a good charge and you should be fine

You don't need a 24 volt motor on a 14 foot aluminum boat.  

You don't need a 24 volt motor on a 14 foot aluminum boat.

x2

A second battery would be cheaper than a second battery and a new trolling motor.  Unless you just want to go faster.

There is absolutely no need for a 24v trolling motor on a jon boat. It will require two batteries that you will run down if you stand on it all day. Buy a high output 12v and carry two batteries. It will last longer than the 24v will. You will have two batteries anyway, so you can change them out later in the day and have a fresh battery later on instead of the two that are on the weaker side.

I have a straight 24v in my 19' Skeeter and it will throw you out of the boat if you kick it sideways if not careful. With a 24v on that jon boat you better carry plenty of changes of clothes because I promise you it will throw you out when you kick it to the side. I have been out in mine once.