Quote History Originally Posted By majg1234:
12.6v is often considered a "good" battery below that may need replaced.On the otherhand 12.8 on a static battery is considered overcharged.
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That's for FLA. Sealed AGM batteries have a slightly higher resting voltage of 12.7 to 12.8 volts when fully charged, and higher charging amperages using proper AGM chargers.
Personally, if this boat has a single battery, I'd consider replacing it based on age. If you have dual batteries with a switch, then I'd continue to run it until it exhibited lower overnight voltages or sluggish cranking behavior. I always converted my boats to dual battery setups, because the idea of getting stuck out in the middle of a lake or far from home on a river, are not appealing to me. Is this used for trolling motor or electronics as well? Or cranking only?