YET ANOTHER BATTERY QUESTION

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ps23435
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Location: Suffolk, VA

YET ANOTHER BATTERY QUESTION

Post by ps23435 »

Need some advice from those smarter than I please.... house battery bank began boiling off rather suddenly (at least we noticed it suddenly from the sulphur smell and heat). Removed the seat cover to the battery compartment and found both batteries extremely warm with some boil over obvious around the fill caps (2 4D 12 volt lead-acid batteries, 5 years old). Checked the fluid levels and found them low across all cells (not empty)...refilled with distilled water. Used the boat for an overnight. The next day came down to he boat to find the same condition except the boil-off seemed worse (fluid levels still high). Got out the volt meter and found the following:

with battery Charger on: Battery #1: 13.4v, battery #2: 13.2V
charger off: #1: 12.4v #2: 12.2v
Checked all cells with hydrometer with readings of "Fair" (didn't write down the actual specific gravity reading)

Kept charger off and turned battery switch to off; left nothing on in the 12v system except the bilge pump. Hoping the batteries cool down!

On battery charger noted the amp meter was pegged past the max of 30 amps.

My first thought is the charger is faulty and is overcharging the batteries, but would appreciate any other insights. Not particularly good at electrical systems here!

Thanks!

pete
SLIP AWAY #437
Hampton, VA
wolfe10
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Re: YET ANOTHER BATTERY QUESTION

Post by wolfe10 »

Pete,

You really need to pull out the hydrometer to determine the root cause of the problem.

A perfectly functioning charger will boil the heck out of a pair of batteries with just one bad cell. Said another way, charging a 10 VDC battery as if it were a 12 VDC battery will make them boil badly.

So, charge them fully and carefully record SG's.

By the same token, a mis-functioning charger will cause perfectly good batteries to boil. BUT, your voltage readings should have been over 14.0 to cause this to happen.

Be aware that once the battery plates have been exposed, the chances of resurrecting the batteries is small. And, with the damage that can be done by sulfuric acid and the explosive nature of hydrogen gas, replacing the batteries is likely the correct course of action.

If you do remove the batteries, make sure that the converter is off and all 12 VDC loads in the boat are off for a couple of hours. That will minimize the amount of hydrogen gas present and will materially lessen the chances that the spark produced by disconnecting the battery terminals will have explosive results.

Brett
Brett Wolfe
C350 #180
"Vindaloo"
Ft Myers FL
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ps23435
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Re: YET ANOTHER BATTERY QUESTION

Post by ps23435 »

Brett: Thanks. I'll do a more careful look with the hydrometer tomorrow. Followup question.... if it's a bad cell(s) I assume the battery would heat up and boil while charging by the alternator as well? Also, if a bad cell in one of the house batteries would the other battery also boil?

Thanks again!
Pete & Anita
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Hampton, VA
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russp
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Re: YET ANOTHER BATTERY QUESTION

Post by russp »

Hi Pete,

My two bits worth. Firstly if your batteries were just boiling off it is nasty enough, but they are not really boiling, they are outgassing hydrogen and in significant quantities and as Brett says, you need to be very careful you don't blow them and yourself up, particularly if they are in the unvented compartment under the saloon seat.
If you were hitting the batteries at 14+V and they were fully charged then it might make sense that they would outgas, but at the voltages you noted it doesn't.

If you have a shorted cell you should see most of the atomised acid and gas coming out of that cell and it doesn't sound like you have, and similarly it should only happen on one battery and not both. And the battery should go flat in a relatively short time after you stop charging and from your note they appear to hold 12.2 or 12.4V. "Fair" readings equally on each cell on a hydrometer, and 12.2-4V at rest on the voltmeter indicates OK but oldish batteries to me.

Re your question about alternator or charger, if you don't get any offgasing when running the motor, but do when using the battery charger, then your battery charger is most likely the cause although your voltage measurements of 13.xV don't make any sense in that case. If it was 15 or 16V then it would.

I would be very wary of using the battery charger until you get your head around the problem. Might also be worth putting a load on the batteries when not charging from anywhere and see if the voltage holds up. I.e. put a known load on and draw out 50 A-hrs or so, if you can hold over 12V doing that your batteries are probably OK, if the voltage falls off rapidly then one or both are probably dead.

An auto or marine electrician can also put a load tester on them and tell you quickly if you have dead cells or internal shorts or not.

Russ Peel
Avalon #150
Russ Peel
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nybor
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Re: YET ANOTHER BATTERY QUESTION

Post by nybor »

lets see if I can get in trouble adding to this conversation. So far the previous responders have all made good points. How about disconnecting one of the batteries and see if the outgassing occurs? If not, then try the other one. However, if both do it (separately charged) then it is your charger. So, do you have another charger available? Walmart sells an automatic (Shumacker?) that you could try to see if it does the trick. That would show that the charger is bad.

dave
nybor
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Re: YET ANOTHER BATTERY QUESTION

Post by nybor »

i knew i should have thought about my previous post a bit more. Of course BOTH batteries could have bad cells. Like someone said, check via a load resistor and monitor the voltage drop (hopefully it will be minor)
dave
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wcconway
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Re: YET ANOTHER BATTERY QUESTION

Post by wcconway »

We had the exact same problem start up last week. Our original batteries are 4 years and 9 months. We are changing them out (very carefully) tomorrow with AGMs from West Marine.
Wally & Coco Conway
, #467
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ps23435
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Re: YET ANOTHER BATTERY QUESTION

Post by ps23435 »

wcconway: How did you determine it was the batteries that were the problem?
Pete & Anita
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ps23435
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Re: YET ANOTHER BATTERY QUESTION

Post by ps23435 »

First, thank you all for the information and insights! It's all been very helpful in trying to get my head around the problem. I think I have determined that there is definitely one bad battery. After about 24 hours of the charger being off and no 12v load, I took another set of readings. With the batteries cooled off it was easier to get better hydrometer readings. The readings on one battery were all above 1.2; that battery also showed 12.31v after no charging. That battery held with 12.5v with a 20a load on. The other battery however showed 2 cells with hydrometer readings of only 1.1; it also had only 8.28v after the day of no charger. Clearly that battery is done! I am still perplexed as to why both batteries were gassing off and hot, but regardless intend on replacing both of these original 4D batteries. I still have not seen more than 14.1v when the charger is turned on so based on what everyone is saying it would seem the charger is not the underlying reason. So now to figure out how to get the 4Ds out of the box and off the boat and then what to replace them with....next week's project!

Again thanks. Any other thoughts/suggestions welcome!
Pete & Anita
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Hampton, VA
wolfe10
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Re: YET ANOTHER BATTERY QUESTION

Post by wolfe10 »

So, why were both batteries out-gassing.

Quite simply, your converter was trying to charge an 8 or 10 volt battery as if it were a 12 volt battery.

So, all cells will be overcharged. That is why it is so dangerous to continue charging a bad battery-- severe outgassing. This risk is magnified in an enclosed environment like under the seat. In addition to the explosive hydrogen gas, sulfuric acid is given off-- not good for wiring, upholstery, etc.

Replace BOTH of them, as they function as a pair.

Brett
Brett Wolfe
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wcconway
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Re: YET ANOTHER BATTERY QUESTION

Post by wcconway »

Changed out our ~5 yr old wet cells with AGMs today. Will write up a post with pictures in a couple days.
Wally & Coco Conway
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ps23435
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Re: YET ANOTHER BATTERY QUESTION

Post by ps23435 »

Thought I would “close the loop” on my battery situation….replaced both house batteries this weekend. The job was surprisingly uncomplicated with the hardest and most time consuming part being changing the configuration of the “hold down” wooden slats as the existing ones would not fit across the new batteries. I opted to replace the 2 Nautilus 4D 12v batteries (6+ years old) with 4 6v golf cart batteries. I went with the Duracell EGC2 for the new batteries. They were easily available at Sam’s Club for a reasonable price; their specs compare favorably with the Trojan 105s which many seem to use (getting Trojans would have involved more time) and they are manufactured by Deka/East Penn which has a good reputation (I’ve had good experience with their batteries before)- and they weigh a lot less than the 4D! Considered AWG’s but balancing expense, availability, size & how we use the boat, went with the wet cells –maybe next time. After reading many posts, we were dreading getting the large 4Ds off the boat….contemplating everything from using some sort of ramp to push/pull them out of the boat to using the spare halyard to hoist them out. We were pleasantly surprised to find that after getting them out of the battery box by tilting them on their long axis, 2 of us were able to lift them using the handles on the battery. We covered all surfaces and carefully lifted from the cabin deck, up a step at a time to the cockpit and then up to the gunwale and off the boat to a dock cart. Yes, they were heavy, but being careful to lift with legs and not back it wasn’t near as difficult as we’d imagined! All in all took about 20 minutes. Putting in the 4 golf cart batteries was quick and easy. Wiring them required 2 jumper cables – I only could find 4AWG gauge cables so used them, but have 2 2AWG cables being made and will replace them next week. Easily the most difficult part was reinstalling the braces and “tie downs.” The Durcell battery has linked fill caps, so reinstalling the wooden braces across the batteries would not work. Took some "thinking" and and a trip to Home Depot, but we were able to install braces along the length of the battery and a new block at the foot to lock them into place. That took some sawing, and drilling new screw holes.

After turning the switches on, had power, voltage was within expected ranges, the battery charger seems to be working OK (though I may do some more checking on that before I leave it on). Will be checking electrolyte levels regularly and will see how things go!

Thanks for all the insights and suggestions!!
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Pete & Anita
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Fat Cat

Re: YET ANOTHER BATTERY QUESTION

Post by Fat Cat »

Our batteries are to be replaced next week with AGM's. The marine electrician was quite concerned that the battery compartment wasn't vented. Is this proper construction?
wolfe10
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Re: YET ANOTHER BATTERY QUESTION

Post by wolfe10 »

Fat Cat wrote:Our batteries are to be replaced next week with AGM's. The marine electrician was quite concerned that the battery compartment wasn't vented. Is this proper construction?
With AGM's, venting is pretty much a non-issue. They only out-gas under SEVERE overcharging (unlike wet cell batteries). In fact they are legal to ship by air freight in the U.S.
Brett Wolfe
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ps23435
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Re: YET ANOTHER BATTERY QUESTION

Post by ps23435 »

Seems to me, that while venting is a "nice to do," hundreds (if not thousands) of boats have been built and are in use with battery compartments similar to that of the 350 and have wet-cells installed.. If it were a major safety hazard that would not be the case. If I were having a custom boat built, sure, vent the compartment, but even having wet cells I don't worry about it an awful lot. And, as was just mentioned, using AGMs pretty much resolves the issue anyway!
Pete & Anita
Slip Away #437
Hampton, VA
Fat Cat

Re: YET ANOTHER BATTERY QUESTION

Post by Fat Cat »

Yes, the new AGM batteries will not require a vented cabinet, although it seems a common belief that wet cell batteries should be. As to my current problem, we will be getting new AGM's next week because several cells boiled and were extremely low on fluid. I understand that a bad cell can cause overcharging and this problem has now gone from bad to worse. Question here: do many Catalina's have the Charles 30 battery charger installed? I've had a good look over this device and there seems to be no adjustment for charging different battery types. If we switch to AGM's, should a compatible charger be installed at the same time?
leigh weiss
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Re: YET ANOTHER BATTERY QUESTION

Post by leigh weiss »

Fat Cat,
You might want to consider the alternator/regulator upgrade for the new AGM batteries.
I used a 110 amp alternator and a ARS-5 regulator set for AGM batteries for my two 4D AGM replacement batteries.
The 100 AMP Charger/Inverter is now set for AGM batteries as well.
For greater belt life I changed the "V" belt to a serpentine belt with a kit I purchased from Bata Marine. It was a bolt on conversion that took less than an hour. All seems well and quiet with no belt dust!!! I can send some pix if you want to see the install.

Leigh Weiss
Upper Chesapeake Bay
Brisa #155
Leigh and Donna Weiss
Brisa #155
Georgetown, MD. USA
KenKrawford
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Re: YET ANOTHER BATTERY QUESTION

Post by KenKrawford »

Fat Cat, there is a switch on the back of the charger that will allows you to select AGM batteries. Don't ask me who the genius was that decided that the entire charger had to be unmounted in order to switch battery types.
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Ken Krawford
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C350 # 351
Lake Lanier, GA
Fat Cat

Re: YET ANOTHER BATTERY QUESTION

Post by Fat Cat »

Thanks to both of you for the good advice. Sadly, I have no literature on this battery charger and never would have found that switch. I'll let the electrician know, maybe the battery charger is still good. Now... when you leave the dock and have all other breakers off, do you leave the charger running? Does this charger provide a "float" charge, or does that only happen on newer Charles 30 models?
KenKrawford
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Re: YET ANOTHER BATTERY QUESTION

Post by KenKrawford »

Fat Cat - I believe you may have the Charles 93-12302SP-A charger. If so, here's a link to the owner's manual. It's really geared towards installation but you might find it useful - http://www.charlesindustries.com/marine ... argers.pdf
Ken Krawford
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C350 # 351
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