Checking and Charging the Battery

1 Measure the specific gravity of the battery acid. In a fully charged battery it should be 1.28. A specific gravity of 1.21 corresponds to a 50% charge.







In the normal case the battery can be charged with a conventional battery charger.

2 For boost-charging, the battery's negative terminal must be disconnected and the water refill plugs should be removed.







During boost-charging, the charging current should not exceed 40 A. Max. charge time 1.5 hours.


IMPORTANT
Do not boost-charge a battery if the voltage is below 12 V or if the battery is more than two years old.


If the battery has been run flat, because a lamp or other consumer was left on, a weak starting charge is required to initiate the chemical process in the battery. In such cases, start with a charge current of about 3 A (it must not exceed 5 A) for 24 hours until the charge current has fallen to its lowest steady value.







The battery begins to give off gas at 14.4 V.
In the above case, a battery charger with a pulsating charging current should be used for preference.