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Battery water maintenance
Flooded batteries need water. Watering must be done at the right time and in the
right amount or else the battery’s performance and longevity suffers.
Water should always be added after fully charging. Prior to charging, there should
be enough water to cover the plates. If the battery has been discharged (partially
or fully), the water level should also be above the plates. Keeping the water at the
correct level after a full charge ensure that you will not have to worry about the
water level at a different state of charge.
Depending on the local climate, charging methods, and application, Trojan recom-
mends that batteries be checked once a month until you get a feel for how “thirsty”
your batteries are.
Important things to remember:
Do not let the plates become exposed to air. This will damage (corrode) the plates.
Do not fill the water to the cap. This most likely will cause the battery to overflow
acid, consequently losing capacity and causing a corrosive mess.
Do not use water with a high mineral content. Use distilled water only.
CAUTION:
The electrolyte is a solution of acid and water so skin contact should be
avoided.
Step by step watering procedure:
1. Open the vent caps and look inside the filling wells.
2. Check electrolyte level; the minimum level is at the top of the plates.
3. If necessary add just enough water to cover the plates.
4. Put batteries on a complete charge before adding water (refer to the Charging
section).
5. Once charging is completed, open the vent caps and look inside the fill wells.
6. Add water until the electrolyte level is 1/8" below the bottom of the fill well.
7. A piece of rubber can be used safely as a dipstick to help determine this level.
8. Clean, replace, and tighten all vent caps.
WARNING!
Never add acid to the battery.
Testing
Visual inspection alone is not sufficient to determine the overall health of the bat-
tery. Both open-circuit voltage and specific gravity readings can give a good indica-
tion of the battery's charge level, life span, and health. Routine voltage and gravity
checks will not only show the state of charge but also help spot signs of improper
