Komatsu PC138USLC Operation & Maintenance Manual page 312

MAINTENANCE MAINTENANCE
3. If the electrolyte level is below the midway point between the
UPPER LEVEL (U.L.) and LOWER LEVEL (L.L.) lines, remove
cap (2) and add distilled water to the U.L. line.
4. After adding distilled water, tighten cap (2) securely.
REMARK
If distilled water is added to above the UPPER LEVEL (U.L.) line,
use a syringe to lower the level to the UPPER LEVEL (U.L.) line.
Neutralize the removed fluid with baking soda (sodium
bicarbonate), then flush it away with a large amount of water or
consult your Komatsu distributor or battery maker.
MAINTENANCE PROCEDURE MAINTENANCE PROCEDURE
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