If it is a deep cycle battery, and it should be, you cannot successfully load test it. A deep cycle is designed to deliver the voltage differently than a “standard” lead/acid. Also, as others have said, check the battery voltage before connecting the charger, then while its charging and after it has been charged. If the battery was fully charged and you took it off the charger, drove to the lake, and it failed, then there is either a battery problem and/or a connection problem. Before doing anything, I would take the leads off the battery and clean both with a wire brush, even if they dont look bad. Also, pop the cowl and disconnect the ground at the motor and clean it. One other thing, you didnt say what battery you had, but when you said Interstate checked them, I assumed it was lead/acids. If its AGMs, the battery could be giving your charger a false reading. Once an AGM discharges to a point, a battery charger will read it as charged, but will not bring the battery up.JohnJones Trolling Motor Services870 773 3474Motorguide/MinnKota/PowerPole/Lowrance/Humminbird
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