Thread: battery help
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id10t id10t is online now
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battery help

Running a 12v trolling motor off a 12v deep cycle marine battery (100ah rated) but having some confidence issues and lack of trust with it and my cheap ampmeter "gas gauge"

When my charger says "done" my ampmeter will show 86% charged with no load, as soon as I put the motor on full power the ampmeter shows 40-45%, dropping thrust to 3/5 will bring it up by 20% or so ...

The ampmeter will drop from 36% to 0 and stay there, motor still going but at reduced power level, but not a lot reduced.

Math says I should get just under 3 jours run time... but a hour before ampmeter shows empty and power obviously drops

So ... better way to monitor battery charge? im guessing I need a mariene/saltwater rated ampmeter ... or somethibg else?

Any ideas as to why a full charge isnt? Or why I am getting about half the expected run time? Battery is less than 2 years old
Old 06-22-2026, 08:09 AM
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