Battery, Checking and Charging
Battery - checking electrolyte specific gravity - Page 27.4
Battery - checking voltage, Page 27.5 Battery - charging - Page 27.5 Troubleshooting guide - battery discharges itself - Page 27.7
Battery
Battery precautions
WARNING
Battery acid can cause severe burns. When working with electrolyte always wear goggles, rubber gloves, and apron. If electrolyte is spilled on skin or clothing, flush at once with large quantities of water. If it gets into eyes, immediately flush with large quantities of water for several minutes and call a doctor.
Batteries produce explosive gases. Keep flames and sparks away from batteries. Do not smoke near batteries
Battery, jump starting
^ car with good battery must not be running when connecting jumper cables
- connect jumper cables in following order:
^ 1 - one end of positive cable to + post of good battery
^ 2 - other end of positive cable to + post of dead battery
^ 3 - one end of negative cable to - post of good battery
^ 4 - other end of negative cable to engine block of car with dead battery
- start car which has good battery first
- next start car which has dead battery
- disconnect jumper cables in reverse order Battery, removing/installing
- remove battery ground cable
- remove battery positive cable
- remove battery hold down Note
Install hold-down with rounded side down and cables tension free
Battery electrolyte level, checking
- check that electrolyte covers battery plates (including separators) by 5 mm (114 in.)
- check battery electrolyte level indicator on side of battery
Note Only use distilled water when refilling battery
Battery condition, checking Note Weak battery can be caused by:
^ alternator belt slipping (replace belt when glazed)
^ ground straps corroded, loose or broken
^ alternator or voltage regulator defective
^ alternator warning light bulb burned out
^ poor ground connection between warning light socket and circuit board Battery terminals and cables should be coated with grease or petroleum jelly and, if necessary, cleaned to prevent corrosion and ensure good connection Visual checks
- check for
^ cracked or leaking case
^ loose or corroded terminals
^ low electrolyte level. If electrolyte is low, refill with distilled water and fast charge battery for several minutes after cells begin gassing (boiling) Hydrometer test (for batteries with removable caps)
- test electrolyte in all cells
^ average specific gravity should be at least 1.225
- correct for electrolyte temperature if necessary
^ for every 10~F above 80~F add .004 to hydrometer reading
^ for every 10~F below 80~F subtract .004 from hydrometer reading
- if specific gravity is above 1.225, load test battery
- if specific gravity is below 1.225, recharge battery
- if specific gravity varies by more than .050 between cells, replace battery
Specific gravity % of charge
1.265 100%
1.225 75%
1.190 50%
1.155 25%
1.120 0%
CAUTION
Do not expose fully discharged battery to freezing temperature because battery will be damaged by freezing
Voltage test - engine not running (for sealed batteries only)
- turn headlights on high beam for 1 minute to remove surface charge
- disconnect battery ground strap
- check battery voltage with an accurate voltmeter
^ voltage should be at least 12.4 volts
- if battery is above 12.4 volts, load test battery
- if battery is below 12.4 volts, charge battery until voltage is at least 12.4 volts
Voltage % of charge
12.6 or more 100%
12.4 75%
12.2 50%
12.0 25%
11.7 or less 0%
Load test
Note Before load testing, battery must be at least 75% charged
- connect load tester according to manufacturer's instructions
- load battery to 3 times amp/hour rating or 1/2 0~F cold cranking current rating
- wait 15 seconds and read voltage
^ battery voltage at room temperature should be at least 9.6 volts
- if battery voltage at room temperature is below 9.6 volts, replace battery
- if battery is colder than room temperature, voltage under load will be lower. Use table below if cold battery must be tested
Approx. electrolyte Minimum acceptable
temp. ~F (~C) voltage under load
60 (16) 9.5
50 (10) 9.4
40 ( 4) 9.3
30 (-1) 9.1
20 (-7) 8.9
10 (-12) 8.7
0 (-18) 8.5
Battery charging
WARNING
Gases given off during charging are explosive. Do not smoke or allow sparks or flame near a charging battery.
Battery charger must be turned off when connecting or disconnecting cables on battery
"Boosting" a sulfated battery at a high charging rate can cause an explosion!
CAUTION
Do not allow battery voltage to exceed 17 volts. If battery begins gassing (boiling) violently when charging, reduce charging rate. Do not disconnect battery while engine is running
Note
Follow battery charger manufacturer's instructions. Before testing a battery that has been charged, load battery with 15 amps for 1 minute to remove surface charge.
Battery with removable caps
If battery level is low and water is added, fast charge battery for a few minutes after battery begins gassing (boiling). Slow charging current should be approximately 10% of battery capacity. Fast charging should be approximately 80-90% of battery capacity. Remove cell caps while charging
- charge battery according to following table:
Specific Fast charge
gravity
up to
1.150 or less 1 hour
1.150 to 1.175 3/4 hour
1.175 to 1.200 1/2 hour
1.200 to 1.225 1/4 hour
above 1.225 slow charge ONLY
to 1.250-1.280
Sealed batteries
Only slow charge sealed batteries. Sealed batteries, sometimes called "maintenance free," will not accept high rate of charge, making it necessary to charge it for up to twice as long as battery with removable caps. Also, voltmeter reading will not increase as rapidly as when charging battery with removable caps.
Battery (new type filler cap)
Filler cap, removing
- cut filler cap skin at notch (arrow) with pocket knife or sharp-edged screw driver
- insert suitable screw driver into slot
- turn upper pad of filler cap counter clockwise to stop
- remove filler cap
Filler cap, installing
- install new type of filler cap in same manner as old-type filler cap