Battery vent cap

I noticed one of my battery vent caps was loose. I snapped it back on but how do I know I lost any of the liquid that is in there?? Thoughts? I have no clue how batteries work. Thanks.

 

Pull the cap off. If the plates are covered your ok. If the plates are exposed fill with distilled water until the top of the slot. Don't overfill.

Also, more then likely you are perfectly fine.

 

Thanks for the info. I live in New England, won’t the water freeze in winter?

 

The battery is filled with sulphuric acid. It won't freeze as long as the battery is charged.

The acid won't spill out, but the water in the acid can evaporate. The distilled water replenishes the stuff that evaporated returning the acid back to it's nominal concentration.

 

Welcome to the forum

This is EZ - however, batteries have acid in them - take your time, use your head and you will be fine.

1) Wear safety glasses.

2) Wipe the top of the battery down with paper towels and immediately put them in the garbage. (remember the acid)

3) With a putty knife or flat screwdriver gently work the caps off, lift them straight up - you don't want to knock any dirt in the battery.

4) You might find dirt under the cap, carefully wipe it away with the paper towels - again keep it out of the battery.

5) With a flashlight look inside each cell, if needed slowly add distilled water so the level is above the plates but below the ring like the photo below. In freezing weather do this just before driving so the water will mix well. A little squirt bottle works well for this.

6) Make sure the caps are clean and gently tap them back on, wash your hands well and check the level again in 6 months.

 

Thanks everyone for the great info!