Blown fuse on trolling motor

[Toba]

My trolling motor is a 12v and was running off of one battery in the past. This year I put two batteries in and ran the + to + and - to -. I am wondering if I need a larger inline fuse because I added the other battery? I blew one fuse yesterday. This I probably a simple question for many of you.

[delcecchi]

My trolling motor is a 12v and was running off of one battery in the past. This year I put two batteries in and ran the + to + and - to -. I am wondering if I need a larger inline fuse because I added the other battery? I blew one fuse yesterday. This I probably a simple question for many of you.

Adding another battery in parallel shouldn't have made a difference to the fuse. Inspect the wiring and jumpers to make sure that there isn't some sort of contact to something that isn't supposed to be contacted. Like, could the battery hold down have pinched a wire?

[Toba]

I replaced the fuse and that seemed to do the trick for now. I will check for pinched wires.

[jmd1]

by adding a second battery you didn't do anything but increase the reserve capacity. The voltage is still 12 volts. For the fuse to blow, it had to have some type of high resistance such as a power wire touching a ground, a loose ground, or short in a control or motor. Also if the motor is rated for 60 amps and you are using a 50 amp breaker (fuse) when you try to pull more power it will blow it.