Trolling Motor Battries

[loadmaster]

Hear is my problem.  Used the heck out of my motor yesterday got home and plugged in charger I charge one battery at a time.  My charger shows 0-100% charge with voltage that battery is at and charger output.  First battery showed 9%  charged and volts 12.5.  Left charger on all night and this AM it showed 100%  Started charging second battery and it showed an 80% charge with 12.5 volts.  I am sure one of these are bad but which one.  Seems like all the juice is coming from one battery but this is a 24 volt motor. not sure how this works.   Put a battery tester on both batteries and both showed good.  Have not changed any wiring and all connectors look clean and free  of corrosion,  Any ideas 

[Jeremy airjer W]

When you charge them one at a time with a twelve volt charger is all the wiring for the trolling motor still hooked up? If so wouldn't the battery that is not hooked up to the charger still be getting charged?

[ewcorlew]

I think if you really think one of the batteries is bad you need to disconnect them and have them Load tested at Tires plus or ? . That is the only way you will really know if they are holding a charge. I don't think they charge to test them.

[loadmaster]

I do not think it is charging both batteries as the current is not going thru the motor.   Come to find out, one battery was on its last leg and the other on the verge.  Did a load test.

 

[Chris Haley]

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