Schematic, batteries boiling over

[grandx]

Have (2) batteries on board with switches, both switches in off position when stored. When I show up to get boat ready for fishing, I check batteries charge and water level occasionally. Sometimes I can hear batteries gurgling inside the battery boxes. Both are boiling over with lots of activity ..not being charged, just sitting in the closed in metal barn. Is this a sign of something bad? I top off the fluid and charge, so far no problem, just wondering why... my car battery doesn't do this to my knowledge.

 

[grandx]

Re: Schematic, batteries boiling over

To the top for a little while.

 

[almost retired again]

Re: Schematic, batteries boiling over

Hi Grandx,<br />It sounds like you have a short somewhere. Batterys will gas while charging, or discharging, and if it's sitting in your barn it's surely not charging. Check for a current draw with everthing off. If you need help with this just ask.<br />Good Luck

 

[grandx]

Re: Schematic, batteries boiling over

Retired, thanks for responding. Batteries share a common ground. Have seperate battery switches to (+), both in the OFF position. There should be nothing on my boat with power with both of these switches off, including the (2) engines. I have a digital meter, when I heard both batteries gurgling, I decided to check em out. Both switches were in the off position, both showed the same 12.3V, both had spilled about 1 oz of acid over into tray. I pulled caps, filled with cells with water and charged at 2 amps with batteries in parallel, next morning they were both at 12.5V, and I went fishing. Boat had been in storage for two weeks with no one touching it. You say maybe a "short", I'm thinking the short must be in one of the switches, cause nothin can get power with switches "off". one more thing, I usually jack trailer/boat way up to drain bilge out of drain plug at back otherwise it gets kinda smelly. If battery is not sitting very level, could this cause something I'm not aware of???

 

[grandx]

Re: Schematic, batteries boiling over

To the top, anyone an expert with Pb/acid batteries? Where are you Schematic?

 

[amtsst]

Re: Schematic, batteries boiling over

we have a couple of things going on here and need some clarification.<br /><br />If you have a short, you know it because you have dead batteries, sparks, wiring that is hot to the touch. ie: BAD.<br /><br />If all you're commenting on is the gurgling, you don't have any problems. The deep cycles often gurgle during charging and it has to do with the charge that is applied to the acid in each lead cell. Its actually bubbles forming at the bottom of the plates and then rising to the top of the cell. The gurgling should stop within a minute or two after you stop the charging. Also, the higher the amps you're passing in, the more vigorous the bubbles.<br /><br />If you have a sealed battery, don't worry about it. If you have an open (fillable) cell battery, loosen the caps and place a plastic device underneath to catch anything that splashes out. *Don't* use garbage bags. I found out the hard way.<br /><br />You noted that you didn't think the batteries were chargin. Can you elaborate?<br /><br />Also, the voltage variation between your two readings isn't uncommon. The question is whether you're drawing any *amps* when those switches are off. If you are, one of your master kills is bad. If not, its normal discharge from sitting.<br /><br />Last item. I realize you check your fluid in the battery (after re-reading your post) Are you overfilling them? you should just cover the top of the plates, not fill to the top.

 

[Scoop]

Re: Schematic, batteries boiling over

The only way to check to see if you still have a power drain on your batteries is by using a ampmeter between the battery and the load. Disconnect the battery and put the ampmeter in series with the battery. Make sure you have the switches off. If the switches are on or you have a huge short, a regular ampmeter could burn out. If you don't have a ampmeter, a test light would work if wired in series. Good luck.

 

[grandx]

Re: Schematic, batteries boiling over

Backwater, thanks for takin the time to read.<br /><br /> Now to calrify my earlier statements: Batteries were not filled to the top (just to the bottom of the slot inside the holes), batteries were not being charged for a 2 week period prior to me opening the barn and listening to them gurgle (much more than a couple of minutes after charging last), I agree, they were similar to batteries being overcharged at too high a rate. I open the battery compartments to find (2) batteries, Isolated from each other, both switches off, no charger attached, and both boiling over with acid (very active, as if I were charging them at 10A). Batteries are 2 years old duel use starting/deep cycle. What the heck is causing all this activity in a couple of batteries that are just sitting (both are doing exactly the same thing and should be isolated from each other, both switches would have to be bad, for them to be connected). If they were stored in an inclined position, could this cause this type of activity??? Keep em comin, I'm readin.

 

[grandx]

Re: Schematic, batteries boiling over

Thanks for the reply, scoop. I don't think I have a short, as both batteries had 12.3V after 2 wks of sitting nearly fully charged. Lookin for more comments, back to the top.

 

[grandx]

Re: Schematic, batteries boiling over

^ to the top, you guys can bury them quick. Still not conviced anyone knows whats goin on here.

 

[MGuckin]

Re: Schematic, batteries boiling over

It does sound like a short.<br />Have you disconnected the battery's from everything including the switch? (Total isolation)<br />Could be a slight leak in the switch or cables, but not enough to kill the battery's,"yet".

 

[steelespike]

Re: Schematic, batteries boiling over

Grandx, try leaving the boat level one time.<br />Also remove everything from terminals, see what happens.<br />Check fluid level after charging, only add water then.Recharge if you feel it necessary.<br /> Do they seem to lose electrolite equally from all cells?

 

[grandx]

Re: Schematic, batteries boiling over

Spike, I would say that I am loosing equal amounts of electrolyte in each cell, does this lead you to some conclusion?