I've now been through 2 trolling motors in the last year or so. My first was a new Newport 62 lb and I had my speed control switch melt on me after a summer season. I replaced it and it worked again perfectly for several months but it died again recently. This time after disassembly there are no obvious signs of what is wrong.
I replaced it with an old Minn Kota Model 35 from the 90s that my friend had, and it worked great but again the speed switch went on it. The unit only worked in reverse and when I disassembled that one it was a loose connection inside the speed switch but you can't disassemble further like newer models, and finding this part for replacement is impossible given how old it is.
My first thought was a bad battery, but it's a highly rated LiFePO4 with BMS. I've tested it many times and it's always 13.3v which is expected for this battery (Newport on their website officially reports their motors can be used as high as 13.7v.)
Despite my testing this must be caused by the battery? It is not uncommon that I may use it full speed for about 10 minutes straight to get from one side of the pond to the other if it could be overheating? This is attached to just a 12" plastic jon boat.
I am tentatively just going to buy an old school deep cycle marine battery and a new Minn Kota and call it a day.
Posted by neuroticelite
2 Comments
Are you running it on top speed for extended times? That could definitely cause this exact issue, even running it 90% would be better than 100%. Same issue twice speaks to operator error but doesn’t definitively eliminate other options, I don’t think the battery would be the issue though.
Only other thing I can think of is poor connections or too small a gauge of wire but that’s highly unlikely. What connectors are you using? Do you have a 50 amp breaker in line? It should be 8-10” from the positive pole of the battery.
The battery is very likely not the problem.
Were you running the Newport at full throttle for extended periods of time? Any traditional style of trolling motor where the control head is strictly passively aircooled will have major heat issues when ran at full tilt for extended periods of time.
That 62lb variant will draw 58 amps at full tilt which can be a tremendous amount of heat build up after a few minutes. I’m trying to find their suggestions on 100% throttle limits, but haven’t found it yet.