I have a boat that I am working on and they put new battery in 5 years ago and then stopped working on it. the owner died. and now we bought the boat and wanted to know what you guy's thought about the battery well they hold a charge.
*Depends. . . *if they have been maintained and are on a modern marine charger that cycles the batteries, then they should be ok.* My 4D's*usually last 8 to 9 years.*
But if they have been sitting there with no maintenance or haven't been*charged properly, then they are probably*toast.* As Rt said, get a load tester and hydometer, bring them up to a full charge and test them.
That's the only way you will know for sure.