Open the plug at the top of the battery and with the help of a special device, a hydrometer, measure the density of the electrolyte.For this purpose, a glass tube, inside of which is a float type electrolyte and division on the float, determine its density.If the density is less than 1.12, then restore it is unlikely to succeed.
Fully charge the battery before it until it boils electrolyte banks.This density should rise to 1.26-1.28.It is advisable to carry out several full charge and discharge cycles, this charge the battery using a small current, then discharge to 10.8 volts, connecting for a few hours, the resistance of
50 ohms or bulb 20-30 watts.
Then multiply the current by the time during which the battery is discharged - so you calculate the value of real capacity.Repeat the whole cycle again.After these manipulations capacity and density should increase.Again, measure the density of the hydrometer.
If after all ranked as actions specific gravity of less than 1.26, then adjust it by adding the electrolyte density of 1.40.To remove some of the pear electrolyte from the battery, and instead add the new electrolyte with high density, while the density of the resulting composition will not reach the desired value.
Then again, a small current to charge the battery, not more than 2 amps for half an hour in order to give to mix electrolyte.Again, check the density, and if it is smaller than normal, again, add electrolyte.
It is not recommended to fully drain the electrolyte from the battery, as in this case can be closed garbage plate, which breaks away from them, and settles on the bottom of the jar.