Proper 6v Battery water level?

Good to know. I wonder if I can find the Mfg instructions.

Just touching the split ring would be the max and may still push some sulfates out. 1/8" to 1/4" below the split ring is best IMO. If the battery is low on charge only fill to cover the plates. Fully charge the batteries and then top it off with distilled water. The electrolyte volume increases as the battery charges.

Or just get a watering system to reduce the hassle and increase the safety.

Follow your battery manufacturer's instructions. Wear safety glasses! For instance Trojan says:

Important Things to Remember

Do not let the plates get exposed to air. This will damage (corrode) the plates.
Do not fill the water level in the filling well 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 or deionized water only.
CAUTION: The electrolyte is a solution of acid and water so skin contact should be avoided.

MN Ben wrote:
Thanks. I topped them up to the bottom of the ring with distilled water
I have had a chunk of the white battery crust in my eye before. One of the worst pains I have experienced.
Thank for the info.
Ben

That is a nasty to even think about.

That's where it should be. The way you got them was a transport level. But with all the battery guys on this forum would you isolate your question here? This isn't a TC question and lots of folks make this mistake

Thanks. I topped them up to the bottom of the ring with distilled water
I have had a chunk of the white battery crust in my eye before. One of the worst pains I have experienced.
Thank for the info.
Ben

I keep mine about 1/2" below the ring. If it is to full it tends to get the top of the battery wet.

there should be something in the holes that as the water comes up, it contacts this ring, and you see the water look concave. Until it hits this ring it looks flat. fill it until you see this. but use eye protection, that is some nasty stuff inside there.
I use a turkey baster and cheep distilled water. (definitely want distilled water)

This level also changes with state of charge. if battery is dead, level will go down.

It should be to the bottom of the hole with distilled water only.