Battery Woes

[Drydocked]

I have three Sears Diehard batteries, date coded D28, two Group 27, one Group 24. The boat was sitting for several months, then I charged the batteries 3 times for 48 hours or more using a Guest 2623 on-board charger.<br /><br />After charging, the batteries start at 13.0V, then lose voltage, dropping to 12.6V within 4 hours, and 12.4V within 24 hours. Seem stable at 12.4V. When I run the boat, the alternator never gets much above 12.5V.<br /><br />Based on everything I've read, it seems like the batteries are toast. Is this true?

 

[Easttxhunter]

Re: Battery Woes

Your batteries should read between 12.4 to 12.6 you need to put a load of half the cold cranking amps on the batteries and see if the voltage goes below 10.5 volts while under a load. This can be done with a carbon pile type tester. If they hold up under a load and stay above 10.5 volts your batteries are good. Now you need atleast 13.5 volts coming ot of the alternator to push the EMF or electric motive force back to the batteries. From your describtion it sounds like an alternator problem. With the carbon pile type tester you can also check to see how many amps your alternator is putting out. Any local automotive place should be able to test these for you if you doint have a battery tester. Hope that helps

 

[JB]

Re: Battery Woes

Nope. Your batteries are behaving correctly. Your alternator, on the other hand chargeth not. EastTXhunter hit the nail on the head.<br /><br />Red sky at night,<br />JB