After living with recurring brake problems on my Columbus 320 I finally changed out the brakes and put new seals, brakes, magnets and packed wheel bearings. Still not satisfiyed with the brakes and after checking the voltage to the brakes, it reads 10.2 volts. I thought someone said it should be 12.2 volts. If so, what and where do I look next? Brakes just don't seem to be applying hard enough when stopping.