Marinette Boat Forum

while working on the boat I found one of my batteries was very warm, almost hot. Took it out and replaced it and my battery dealer told me the on board charger was overcharging the battery because of a bad cell in the battery and the charger would not shut off. He said the battery could have even burst.I had no idea that the on board charger could continue to charge a faulty battery and not shut down. The charger works fine with a new battery and shuts down or goes to a trickle charge as needed. It was amazing how hot that bad battery got. Just a heads up to all.

Just had the same experience with an AGM, Optima Red Top, battery was eight years old. Hot to the touch and would only reach 10 volts. Had it on a Battery Tender. Curious as to what kind of battery you had?

It was an interstate AGM battery that was several years old.

what manufacture battery charger are you using and is it 1-2-3 bank charger? My boat still has the original and am thinking about replacing it.

Was using a Battery Tender on the one that overheated, no fault of the charger battery was just worn out. Recently purchased a Newmar PT-14W, have used there ABC chargers for years with good results.

I like the higher end MinnKotas that actually (supposedly) will maintain the plates. but I don't see many people using those on bigger boats. Am I missing something?