It is easy to rewire the boat. Batteries are very simple in reality. You have 12 volts and end the positive and negative from each of 2 batteries to the wiring going forwards and the middle positive and negative posts need a jumper wire for producing 24 volts. Or 2 x 12 = 24… He has a 36 volt set up so he has a jumper wire between each of the three batteries somewhere. Charging is two options each battery as one 12 volt, which can be done by one charger one each battery, or one lead from a Multi bank charger to each battery. The other option is a 24 volt charger connected to those same 2 end posts of each of those 2 batteries. In the evnt he has tried the 36 volts on a 24 motor. Using 36 on the 24 volt will work for an unknown time as the motor is not wound for that much voltage and will overheat. Either internally failing or stopping when it heats up from safeguards. Most on high shut down in minutes use, those on low power last that unknown time frame. Usually it is not catastrophicly damaged though it overheats and stops. Cooling will allow it to function again and the life span is shortened more each time. This explanation is in the event of him having done that and not a try this! – or Watch This!!! 24 and 12 volt DC motors each handle more power than the higher voltages. 24 handles 30, 12 handles 18 and 36 might handle 42 though the percentage narrows as ratings increase. Everyone makes batteries hard and stacking 1.5 AAA, AA, C or D batteries on end in a flashlight produces more voltage by 1.5 volts with every battery added. Thus that long maglight with 4 batteries is now a 6 volt. Some game cams are 12 volts and some are 6 volts which is why they require more batteries.Make batteries simple by thinking them through and weight applies to all batteries. Heavier is better in most cases.
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