You might be able to recharge it if you leave it on a slow charge rate for 24 hours or so. Some chargers won't start if the battery is below a certain voltage. If your charger has an 'override' button or something other than just on and off, push that button after connecting the leads. But make sure your charger connections are correct before starting the charger- if the battery is completely dead and you connect the charger backwards, and it starts, it will charge the battery with reversed polarity- if it will charge. If you don't have some kind of override, connect another charged battery in parallel to yours, then connect the charger and turn it on. Leave the two batteries connected for a few minutes, then shut off the charger and disconnect the 'good' battery. Then try again to charge the dead battery. You might have to do the parallel battery connection again if the charger does't start up after the first attempt.
So as not to misinterpret the charger indications, a completely dead battery has high internal resistance that limits the charging current to a very low level. The charger ammeter may not show a charge current for several minutes after starting, so leave the charger connected for an hour or so before concluding that the battery is not charging. You should have a voltmeter connected to the battery when you are charging it. If the voltmeter comes up to 13 or 14 volts when you turn on the charger, good sign, even if the ammeter needle doesn't move. If you have charging voltage, leave everything alone for a while, but check for the charging current to increase after an hour or so.
If the dead battery charges, leave it on the charger for 24 hours or so. If you don't have a battery hydrometer, buy one, preferrabley one that is temperature-compensated if you can find one, but non-compensated is all right- and they are most readily available. When the specific gravity reaches around 1.280 warm, the battery is charged. A little over 1.280 is all right, but much below that level when the battery is warm means it still needs charging.
If it were my battery, and if it charges more or less satisfactorily, I would next discharge battery completely with a low discharge rate, like car low-beam headlights or parking lights, and let the battery stand dead for 12-24 hours. Then recharge the battery to 1.280 specific gravity. At two years old, it is quite possible that it will return nearly to full capacity.
After all the charging is complete, if it is, wash the exterior of the battery completely with water and baking soda and dry it completely. Don't get any of the soda solution inside the cells. That will neutralize the acid and undo all your efforts.
Hope this helps.
Harvester
