Charging Procedure
The following procedure should be used to recharge a very low or completely discharged battery:Hydrometer Check - Clean the cover, look into the built-in hydrometer and use a flashlight if necessary, to observe its reading. To ensure an accurate reading, gently tap the top of the hydrometer to dislodge any air bubbles that might cause a false green, clear or light yellow appearance.
Green Dot Visible - Any green appearance is interpreted as a "green dot" and indicates that the battery is 65 percent or above in state of charge and is ready for use or testing. A fully charged battery should have an output of 12.6 or more volts at the terminals.
Dark (Green Dot Not Visible) - Indicates the battery is below 65 percent state of charge and needs charging prior to testing.
Clear or Light Yellow - Indicates the fluid level is below the bottom of the hydrometer. This may be caused by a cracked or broken case. A battery in this condition should be replaced. Excessive or prolonged charging, excessive tipping or normal battery wearout can cause a clear or yellow light and battery replacement is required. Do not charge, test or jump start. A dark reading may be misinterpreted as a clear or light yellow reading when inspecting a Delco Freedom battery. Gently tap on the top of the hydrometer to dislodge any air bubbles that might cause a false reading. If the hydrometer remains clear or light yellow, the battery should be replaced.
Measure Terminal Voltage - Measure voltage across the battery terminals with a voltmeter. If below 11 volts, the initial charge current will be very low (milliamperes) and it may take several hours before the battery can accept a charging current measureable by the ammeters used on most chargers.
Connect Charger - Connect battery to charger and connect charger to power source. Set charger on high setting.
NOTE: Do not use "boost", "jump start" or "crank" settings to charge batteries if charger is equipped with any of these settings.
Polarity Protection - some chargers feature polarity protection circuitry which prevents charging unless the charger leads are connected to the battery terminals correctly. A completely discharged battery may not have enough voltage to activate this circuit, even though the leads are connected properly, making it appear as though the battery will not accept charging current. Therefore, follow the manufacturer's specific charging instructions telling how to bypass or override the circuitry so that the charger will turn on and charge a low voltage battery.
Measure Charging Voltage - Measure voltage across the battery terminals with a voltmeter, charger connected and operating. If the initial charging voltage is 16 volts or greater, it may take 4 hours before the typical charger ammeter indicates a
measureable charging current for a deeply discharged battery. If the initial charging voltage is below 16 volts, as many as 8 to 16 hours may be required before charging current is noted on the ammeter. If no charging current is apparent on the charger ammeter after these times, the battery should be replaced. Measureable charging current within these times indicates that charging should be continued in the normal manner.
CHARGING VOLTAGE
Charger Voltage Hours
16.0 or More Up to 4.0 Hrs.
14.0 to 15.9 Up to 8.0 Hrs.
13.9 or Less Up to 16.0 Hrs.
Monitor Battery - Monitor battery hourly for gassing or spewing of electrolyte and battery temperature above 125 degrees Farenheit as judged by feel. Adjust or temporarily halt charging as required to avoid these conditions and permit cooling. Check hydrometer hourly for green dot. Gently tap the top of the hydrometer to dislodge any trapped air bubbles that might cause a false reading. When the green dot remains in view, the battery is charged and ready for load test. If the green dot does not appear after an ampere-hour charge equal to twice the reserve capacity rating of the battery is applied, replace the battery.
Load Test - It is recommended that any battery recharged by this procedure be load tested to establish serviceability.
If the battery is in the vehicle, make sure the engine control switch is off. If there is more than one battery, check each separately.
1. Disconnect the battery cables from the terminals.
2. Install adapter AC-Delco Part Number ST-1201, or equivalent.
3. If adapters are not available, use two 3/8" standard thread (16 UNC) bolts UNPLATED, at least 1.5 inches long, and two standard 3/8" UNPLATED nuts. Finger tighten. Contact must be made through the lead pads at the face of the terminals, not through the threads of the bolt.
4. Install a voltmeter and battery load tester to the adapters.
5. Remove the surface charge from recently charged batteries by applying a 300-ampere load across the adapters for 15 seconds.
6. Do not remove the surface charge from batteries which have been in storage.
7. Turn the load off and wait 15 seconds for the battery to recover.
8. Apply the specified load indicated on the battery label. If a load test figure is not indicated, apply 50% of the cold cranking amp hour rating indicated on the battery specification tag. Observe the battery voltage after 15 seconds with the load connected, then turn off the load.
NOTE: Battery tester cable clamps should be between terminal nuts and lead pads of terminals. If not possible, load value should be 275 amperes.
9. If the battery voltage does not drop below the minimum voltage as shown in the following "Voltage and Temperature" chart, the battery is good and should be returned to service. The battery temperature must be estimated by feel and by the temperature the battery has been exposed to for the preceeding few hours. If the battery voltage drops below the minimum voltage listed, replace the battery.
VOLTAGE AND ELECTROLYTE TEMPERATURE CHART
Estimated Minimum
Electrolyte Required Voltage
Temperature Under 15 Sec. Load
21 degrees C (70 degrees F and Above) . . . . . . . . . . . . . . . 9.6 10 degrees C (50 degrees F) . . . . . . . . . . . . . . . . . . . . . 9.4 -1 degree C (30 degrees F) . . . . . . . . . . . . . . . . . . . . . . 9.1 10 degrees C (15 degrees F) . . . . . . . . . . . . . . . . . . . . . 8.8 -18 degrees C (0 degrees F) . . . . . . . . . . . . . . . . . . . . . 8.5