trolling motor problem

[mrjigger]

I have a 74pd Minnkota trolling motor. It obviously runs on a 24v system. I had two trojan batteries, recently one of them went bad. So I replaced it with a different type of deep cycle trolling battery. When both my trojans were working properly the top speed with the trolling motor was around 2.5mph. I hooked the new battery up with the trojan battery I had and now the trolling motor wont even top 1.0mph. Both batteries are fully charged. I believe I have the batteries wired correctly, but not positive because I just bought the boat used two months ago and the batteries were already hooked up. this is the first I have had to replace a battery. Will the trolling motor even run when only hooked to one battery? Any other thoughts?

[Wade Joseph]

Sounds to me that it is running on 12v vice 24v.

Sounds like you have them hooked in paralllel (still get 12v but double the amperage) You need them hooked up in series to double the voltage. To do this you must have the positive from the first battery hooked up with a short jumper lead to the negative of the second battery. The black lead from the motor on the negative of the first battery, the red lead from the motor onto the positive of the second battery. Brand of batteries should have no effect other than maybe overall life span.

Hope this helps

[mrjigger]

thanks Wade, I will check to see if the batteries are wired as you explained.