deep cycle battery ????

[mikeh]

I have 2 27 series deep cycle batteries and the last three weeks they haven't held a good charge. Took them out of the boat and removed the covers and could see the plates and no water. My question is if I fill them up with water again will they be any good or are they garbage? I have had an onboard charger plugged in and it goes on trickle charge and that is what I think helped evaporate the water.

 

also how often do you have to check your batteries?

[Fisherman]

Well, run down to your local "eco" water store and get some distilled water is best, refill to just over the top of the plates and recharge. Let it sit overnight and add a bit more water, no more than to the bottom of the fill holes where the slot is. If you have a turkey baster, suck up and squirt the fluid in and out of each cell a few times to equalize the acid and water mix, charge for another 4 hours or so. I'm not a fan of leaving some of those so called "trickle chargers" plugged in all the time. Something like a "Batter Minder" from VDC electronics is different, very low input, about 250mA. Check your batteries at least once a week until you figure out the pattern to keep the fluid level up. There's also another prduct out there called "Thermoil", some boohoo it, some swear by it. it's supposed to prevent most of the water from evaporating duing gassing(charging). I've got an old '98 Sears Diehard for the trailer, still going strong, gets less than an ounce of water a year. Maybe they will recover.