Yesterday I brought in my two deep cycle batteries from my boat and the one from my camper for winter storage. I check all of the water levels and had ended up adding some distilled water to each, bring it to just under a 1/4" from the top. I had just purchased a new schumacher 15A/3A auto charger. So far all three batteries have overflowed during charging. Did I get a bad charger? What else coull be the cause of this? My old chargers fan went out last summer so it could no longer handle long charges so I had to purchase the new one. I have never experienced this problem before.Any Ideas?https://www.amazon.com/Schumacher-SC1280-Charger-Automotive-Batteries/dp/B0797KK3N2/ref=pd_lutyp_crtyp_simh_6_1/138-2305690-8086409?_encoding=UTF8&pd_rd_i=B0797KK3N2&pd_rd_r=8f304cdd-ade6-448a-878d-fc63e6f445da&pd_rd_w=b8jI1&pd_rd_wg=kulF8&pf_rd_p=11bf186d-590b-449a-8161-5414a5d28305&pf_rd_r=084BGV1W7V93NMG7TRAY&psc=1&refRID=084BGV1W7V93NMG7TRAY

you over filled them. To the bottom of the ring with full charge

At this point all we can do is SPECULATE.What is charging voltage after a couple of hours (i.e. float voltage)?

philh wrote:you over filled them. To the bottom of the ring with full chargeBy the ring, do you mean fill them to the bottom of the cylinder the caps snap on?

philh wrote:you over filled them. To the bottom of the ring with full chargex2

All I can add is that I had to toss two near new smaller Schumacher maintainer chargers because they ruined two of my AGM batteries...

Why are my batteries water overflowing during charging?

philh
Explorer II
Jan 14, 2020
you over filled them. To the bottom of the ring with full charge
wolfe10
Explorer
Jan 14, 2020
At this point all we can do is SPECULATE.

What is charging voltage after a couple of hours (i.e. float voltage)?
mrad
Explorer II
Jan 14, 2020
philh wrote:
you over filled them. To the bottom of the ring with full charge

By the ring, do you mean fill them to the bottom of the cylinder the caps snap on?
azdryheat
Explorer
Jan 14, 2020
philh wrote:
you over filled them. To the bottom of the ring with full charge
x2
3_tons
Explorer III
Jan 14, 2020
All I can add is that I had to toss two near new smaller Schumacher maintainer chargers because they ruined two of my AGM batteries...
time2roll
Nomad
Jan 14, 2020
mrad wrote:
philh wrote:
you over filled them. To the bottom of the ring with full charge

By the ring, do you mean fill them to the bottom of the cylinder the caps snap on?
You should fill them to 1/4" below the split ring that extends down into the cell. Just touching the bottom is absolute max.

Actually the electrolyte will expand as the battery is brought from low charge to full charge. Best to just verify the plates are covered and top off (as above) after the battery is fully charged.

OK there is a possibility the battery is shorted and excessive bubbling has forced the electrolyte out through the cap.
CA_Traveler
Explorer III
Jan 14, 2020
I would remove the excess ligquid from each battery placing it in a glass jar for that battery maybe to added back later. Then take the batteries to a good battery shop and have them load tested. Load testing involves first fully charging the batteries before doing the load test. Be aware that the battery acid is already diluted some because of the overfill and overflow, hence the liquid is no longer nominal.

If the batteries are OK it might be worthwhile adding some acid back to achieve the correct liquid balance. Perhaps check with the battery shop first and get their input on the overfill. BTW A auto parts store is NOT a good battery shop.

After the load test if they pass then they need to be recharged.
River-Runner
Explorer
Jan 14, 2020
3 tons wrote:
All I can add is that I had to toss two near new smaller Schumacher maintainer chargers because they ruined two of my AGM batteries...

I've just gone from two Trojan T-105 wet cells to four Trojan T-105 AGM's. My first AGM's, so I am in learning mode. I'm currently using a Battery Minder charger w/ AGM mode when in storage. I have a progressive dynamics 9200 series converter/charger installed from the factory I'll use when plugged in on trips..

Why do you say the chargers ruined your chargers, wrong voltage?

Thanks.
2112
Explorer II
Jan 14, 2020
Read the watering section half way down this page:
https://www.trojanbattery.com/tech-support/battery-maintenance/

Water should always be added after fully charging the battery. Prior to charging, there should be enough water to cover the plates.
wa8yxm
Explorer III
Jan 14, 2020
The answer is in your post. also a comment. First the comment
IT IS NOT WATER (H2O). it is sulfuric acid. More on that later (H2S04)

Now you told us what the problem is "ended up adding some distilled water to each, bring it to just under a 1/4" from the top."

The correct fill level is 1/4" from the BOTTOM of the filler tube or split ring.

You over filled by about 1" give or take a bit depending on the battery

Look into the battery see the tube that you pour the water into 1/8 to 1/4" BELOW the bottom of the tube is the proper. many say to the bottom but give it an additional quarter inch to be safe.

Now
Little Willie Was a Scientist
little Willie is no more
For what he thought was H20
Was H2S04

(I can't believe I remember that from more years ago than I care to admit).