Forum Discussion

Rmack1's avatar
Rmack1
Explorer
Apr 15, 2014

battery filling level

What are the consequences of overfilling a battery with distilled water? A little past the bottom of the filler tube?
  • Real good chance of water boiling out and all over top of battery.
    Water expands when heated.....batteries get hot when charging.

    Use an eye dropper, baster, straw with finger over top etc. to lower water level.
    Should be 1/8" below vent tube IF battery has been fully charged.




    IF going to charge battery..water level should just cover any exposed plates and then properly topped off after fully charged
  • Old-Biscuit wrote:
    Real good chance of water boiling out and all over top of battery.
    Water expands when heated.....batteries get hot when charging.

    Use an eye dropper, baster, straw with finger over top etc. to lower water level.
    Should be 1/8" below vent tube IF battery has been fully charged.




    IF going to charge battery..water level should just cover any exposed plates and then properly topped off after fully charged


    DANG! That just beats the living turd outta the answer that I was gonna offer up. Excellent post!

    Cheers!

    Mike
  • wa8yxm's avatar
    wa8yxm
    Explorer III
    As the battery charges some electrolytic (Acid solution) may be expelled via the vent cap.. Thus requiring more frequent cleaning.

    By the way. I know many folks say to fill to the bottom of the filler tube or split ring (Same level).. DEKA (East Penn Battery company) says 1/8 inch BELOW the bottom of the tube.. (I usually say 1/8 to 1/4 inch myself) .

    I just put DEKAs in this house.
  • If the slot in the filler tube is mostly exposed ("a little past the bottom of the filler tube"), do nothing; over time it will go down. Watch during charge and if the level starts to cover the slot completely, you'll have to remove a small amount of electrolyte to expose some of the slot to allow the gasses to escape.

    Doug
  • doughere wrote:
    If the slot in the filler tube is mostly exposed ("a little past the bottom of the filler tube"), do nothing; over time it will go down. Watch during charge and if the level starts to cover the slot completely, you'll have to remove a small amount of electrolyte to expose some of the slot to allow the gasses to escape.

    Doug


    What Doug says. Just don't really ramp up the charging rate on those batteries too much, that will boil the acid up and out. Normal usage or leaving it on a maintenance charger should drop the level, in due time.
  • As long as level is not too low, for example below plates you can charge and only then after completely charging should you add water to bring to proper level.

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