24v trolling motor battery wiring

[doc]

Ok, I was looking over the wiring in my boat this weekend and came across what I think is a problem waiting to happen. Now I'm no expert so I thought I would post it here and ask. I have a 24v trolling motor (minn kota maxxum) and the batteries are setup in the traditional 24v pattern with the trolling motor hooked up to positive on one battery and negative on the other. My concern is the previous owner only had 2 batteries in use, he has the big motor, and all accessories hooked up to the first battery in the 24v chain. Everything is working fine as far as I can tell. I've just always seen the tm hooked to 2 batteries 24v then a different battery used for the big motor and accesories.