Mec 3072ES, Service And Parts Manual

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"3072ES / 3772ES / 3772ES HD" Service & Parts Manual October 2008
Page 2-5
Battery Maintenance (in use)
Check battery and surrounding area for signs of damage or corrosion.
Check battery terminals for:
• Corrosion: Regularly clean connections and apply a nonmetallic grease or protective spray to
retard corrosion.
• Loose connections: Be sure all cable connections are tightly secured, and that good contact is
made with terminals.
• Broken, swollen, or frayed cables: Be sure all connections are good and that no loose or bro-
ken wires are exposed. Replace as necessary.
Check battery electrolyte level and replenish the electrolyte if necessary. Remove battery vent caps
before filling, and USE ONLY DISTILLED WATER. DO NOT OVERFILL. Fill to level indicator (if there
is no level indicator, fill to ½ inch over the top of the separators ). Fill after charging to prevent overflow
of acid due to expansion. Do not use a hose to add water to batteries.
Allowing the electrolyte level to drop below the top of the separators will lead to shortened battery life.
Excessive water usage can indicate that a battery has been overcharged, has been subjected to
excessively high temperatures, or is nearing the end of its service life.
Battery Preventative Maintenance:
Every 15 hours (after battery has been charged), spot-check the specific gravity of two or more cells.
A fully charged battery should indicate 1.28 specific gravity. If low readings are noted, check the
following:
• Check terminals for corrosion, loose connections and broken, swollen, or frayed cables.
• Check all cells with a hydrometer for variance in specific gravity. A variation of 0.03 points or
more between cells is a cause for concern. Mark the low cells.
Recheck specific gravity of all cells after recharging. Wash the top of the battery, making sure all vent
caps are in place. Do not allow cleaning water or other foreign matter to enter the cells. Use a solution
of bicarbonate soda and water (5 tsp. of baking soda per quart of warm water) to wash the battery if
there is an accumulation of acid.
Battery Specific Gravity and Voltage Table
SPECIFIC GRAVITY VOLTS DC
EACH CELL
1.280
1.130
Fully Charged
Fully Discharged
PER CELL
2.10
1.75
12 V BATTERY
12.60
10.50
6 V BATTERY
6.30
5.19