Batteries done?

[keepondancin]

I was able to use the boat for the first time this season after waiting 6 weeks for an engine part. Just had to replace genset start battery, 9 yrs old, suddenly wouldn't hold a charge. Motoring out my tach started jumping around, so I checked charging voltage and it was about 13.8 or so. Everything I have is analog. I have a Balmar 100 amp alt. and Balmar ARS regulator. Sailed for a few hours then motored to the anchorage, same thing. Next morning we ran the gen to make coffee and run the Freedom 2000 charger, which has worked very well for 5 years. The charger stayed at 100 amps but voltage never went to, or above 14 volts. These are all smart chargers that start at 14.4 then step down. Now nothing goes above about 13.6 volts. System is 6-6volt Rolls for house, series 31 engine start. House bank is 10-12 years old, start is about 6. They discharged during the winter when I wasn't around due to a faulty bilge pump and an absent boat checker. My gut is that the batteries are done. The tach acts like it does now when we motor for a long period and do a full charge. When I get in tomorrow morning I will check specific gravity. I have checked water and all connections.

[perchance]

Does it freeze where you are?

[Amnesia II]

My guess is they are all done in! With that many years on them it's time to change anyway.
I had battery issues all the way across the Pacific....totally new bank in now and supported by solar, I never see them below 12.5 volts day in day out.

[deckofficer]

Hate to say it but nothing kills a battery more than being left for a long time period in a discharged state.

[keepondancin]

Yes it freezes here, but I do 't think the house bank froze. That had some charge. So did genset. Engine start was stone dead and that is doing the best. I think they are done, just shudder at the thought of replacing them. Seems like 10 years ago was just yesterday. I just hope I am not hurting the charging systems. HAD to run the e gone for about 4 hours.

[kentobin]

You could play with these and maybe get a season or two out of them. At best the batteries are close to the end of their maximum rated lifetime and you did a deep discharge which doesn't make them happy.

But what is cost of your time to work on them to save a few bucks for one season? If they give out while you're cruising at the very least it will be inconvenient and at it's worst could be life threatening like no running or anchoring lights, radio, windlass, etc.

If for no other reason for peace of mind I'd change them.

Those deep cycle 6v are heavy bastards but not nearly as bad as a 12v 8D.

[Forever Freedom]

9 years seems like a good return on your money to me. What kills batteries is leaving them for a long period only partially charged; the soft sulphation caused by normal discharge becomes hard crystal sulphation and is not reversible. Provided a battery is fully charged, cold will not have an effect unless the electrolyte actually freezes. Cold temperatures actually increase battery life as they reduce parasitic discharge, however they also reduce capacity - hence the difficulty of starting a car on a very cold morning.

[keepondancin]

Just wanted to update. I called two battery suppliers, and they said probably the batteries are finished, and quoted prices. I call RAE Battery, in Berlin, Ct, where I purchased the batteries. The Batteries are Rolls. They had me check s.g. on all cells. They where pretty uniform, but low. They said bring them up, and see what they could do, before I buy new batteries. They checked s.g. again, then load tested them, and the owner said heavily sulfated, let him work on them. I picked them up five days later, and was told there they are now in good shape, and I don't need good batteries. Put them back on the boat, and after 20 hours or so, including runninf the refer, they are still holding a good charge, and the cabin fans haven't turned that fast in awhile. 4 batteries are 8 years old, and two are 6 years. I think I paid about $120-$130 each. They are now $180. I do believe they still have a lot more life left in them. He felt the sulfation was because of age, and the prolonged discharge last winter. I recommend RAE battery, they could have just sold me new batteries. I also feel another case of you get what you pay for. If I get ten years out of the batteries, that is very good service life.