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Battery Electrolyte Level, Checking



Battery Electrolyte Level, Checking

Special tools, testers and auxiliary items required
- Battery filler VAS 5045

Procedure
Maintaining the correct electrolyte level in the battery is an important factor affecting the length of the batteries service life.

CAUTION:
- Risk of injury from direct exposure to battery acid.
- Follow accident prevention regulations when working with battery acid.
- Wear protective eyewear and clothing.
- Risk of explosion due to open flame, fire and smoking.
- Only illuminate the inside of the battery housing with a flashlight.
- Never illuminate the inside of the battery housing with an open flame.
- Never handle open flame or burning cigarettes near batteries.


- If the "min" and "max" marking on the outside of the battery can be seen, simply inspect by sight.
- The electrolyte level must be above the "min" marking but must only go as high as the "max" marking.
- If it is difficult to see the "min" and "max" markings on the outside of the battery or they cannot be seen because the battery housing is opaque, remove the sealing plugs.
- Check electrolyte level by visually checking the inside of the battery.
- The electrolyte level must coincide with the internal level mark (plastic web). This corresponds to the outer "max" marking.

CAUTION:
Risk of corrosion due to leaking battery acid.
- To ensure the various battery connection systems are free of leaks, the batteries original sealing plugs must be installed in the battery openings. Only replace missing or damaged sealing plugs with the same type of original plugs.
- The sealing plugs must be equipped with an O-ring.


- Thread in battery cell sealing plugs.

Electrolyte level too low
If the electrolyte level is too low, a loss of battery capacity (power) occurs due to cell plates drying out. If the cell plates are not surrounded by electrolyte (sulfuric acid-water mixture), the plates, plate straps, and cell connectors will corrode. The corrosion damages battery operation, the battery can no longer be used.







- If electrolyte level is too low, use battery filler VAS 5045 to add distilled water until max mark is reached.

NOTE:
- The filler neck of the Battery filler VAS 5045 is designed to prevent over-filling of the battery cell and electrolyte leakage. The flow of distilled water into the battery cell is interrupted on reaching the max. level.
- Always use distilled water for topping up to prevent electrolyte contamination which results in increased self-discharge.