Are my Batteries Dead-Dead?

[Melody Miller]

Hi Everyone:I'm pretty sure that I need new batteries, but just want to run a few thingsby the forum regulars. Guys and gals, what is the definitive test for knowing that I need new batterries? What's been happening is that I put the charger on after I come in from sailing a few hours and charge the batteries up to 100%. I turn everything off and I come back a week later and no charge on either battery. This is happening pretty regularly. My meter shows that the alternator is charging the batteries when I run the engine. The batteries have ample water. I hesitate to jump to the conclusion that it's the batteries because (1) its both batteries (as opposed to one) that are losing the charge, and (2) the previous owner says the batteries are pretty new (although the month/ year is not scratched out.) I don't think I have any leaks because I turn everything off when I leave. Anything else to consider?The fix I have in mind will cost no less that $300. I am writing about that in a different post.Thanks,Melody

 

[Jeff Walker]

Batteries, the bane of all boaters

Hi Melody,Sounds like I had a similar problem a while back. I had 2 Group 27's that would both be dead when I'd come down with a group of people ready to go sailing. In my case, only one of the batteries was bad but when I turned the selector to "Both" to start, the charge from the good battery flowed into the bad battery and I got nothing. If I turned the selector to "1" the engine turned over but not on "2" (bad side). You have probably done this but I just thought I'd mention it. I also found that keeping a 10 amp Guest smart charger on the batteries all the time helps. The batteries never cycle down below 80% full charge and they have lasted 4 years now with no problems. For your question about battery replacement, Your West Marine guy recommended a good system but you may be able to get by with 2 SeaVolt Group 27 Dual Purpose batteries. They give good cranking amps for starting and act as modified deep cycle batteries as well. About $60/each if I remember. I would put a 3 or 10 amp smart charger (cuts off when fully charged) on them all the time just in case you do have a small power leak in your system. Good luck,Jeff s/v Suzanne

 

[SEAN]

Dead Batteries

Melody, You might try disconnecting your batteries the next time you leave and reconnecting them again. They should still have a charge. If they do, that means you have a drain on them somewhere in your electrical system. This is very hard to isolate. A Guest battery on-off switch would eliminate current from running through your system when your gone. I've used the same batteries for five years and have never had a problem. I have even run a Norcold refrigerater constantly. Hope this helps. Sean-Carnaby Street