So I am thinking of upgrading my trolling motor on my 2007 Triton Aluminum VT-17 from a 12V to either a new 24V Motorguide Tour Pro or an Ultrex. I want gps anchoring. I have a few questions regarding my battery setup. 

 

1) Does anyone know if the wiring is good enough to handle the upgrade? (I would think it should be being a Triton) 

2) I currently run an interstate deep cycle and an interstate marine cranking battery. On my cranking battery, I actually have three leads and I cannot figure out what the last lead is used for. I have the black to the negative terminal, an orange one to the positive (boat starts and runs fine, has for years) and a red terminal that isn't hooked up to anything. Would anyone happen to know what the red is used for? 

 

Also, I understand I would need to add a second battery of the same type in order to run them in line at 24V. I would also add either a 50amp fuse or circuit breaker to the positive lead for the upgrade. 

I can’t speak to the wiring but on the batteries you need batteries of the same age for the trolling motor.  You system is only as good as your weakest battery.