Dry Battery Cells Issue

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New member
Jul 17, 2005
Hi folks.? I'm a newby and this is my first post.? Just purchased a 2003 Gulfstream BT Cruiser and the onboard battery will not stay charged.? It may be a bad battery (it was nearly dry when I checked it) and I'll have to drive it a ways in to town to get it tested.? I'm just wondering if there is something I'm leaving on in the RV that I'm not aware of.? All obvious switches, lights, etc. are off.? Thanks.
Welcome to the RV Forum!

  Is your on-board battery a deep cycle battery?  Is it 6 VDC or 12 VDC?

Dry cells could indicate a charger (converter) malfunction, or just that the battery was neglected during hat summer weather, allowing the acid to evaporate.

I check my on-board batteries on the first of every month, and more often when outdoor temps are hot.  Topping up should be done with distilled water, while wearing long rubber gloves and protective eye-wear. 

Would you describe the electrical system in your RV, such as the number of batteries, the charging and monitoring devices installed and whether the RV is plugged in most of the time or rarely.

In the meantime check the Trojan Battery Maintenance Site which provides details on every aspect of deep cycle battery maintenance.

Glad you've joined the RV Forum..looking forward to getting more information about your battery problem.

Battery is 12 volt deep cycle.  I suspect that the reason it was nearly dry was that it was not properly maintained.  There is only 1 on-board battery.  I just got the RV so I'm not sure of its detailed history but I think that it was not plugged in very often.  It has a converter and inverter.  I assume the generator charges the battery.  If I run the generator a while then turn it off, the battery is strong enough to crank the generator or run the lights a while.  Its usually dead the next morning.  Same happens when I put a charger on the battery and trickle charge it for about 12 hours.  It's good for a short while but won't hold a charge. The system monitor seems to be working (i.e. it indicates low battery when it's low & good battery when it's charged).


It may be a bad battery (it was nearly dry when I checked it)

If by nearly dry you mean the tops of the plates were not wet and you had to add a considerable amount of water, chances are very good that the battery is fried. The previous owner may have driven the "C" a lot and never bothered to check the 'other' battery. Get a new one, but also check that there are no other drains on the battery going un-noticed. A simple procedure is to solder 2 wires to a stoplight bulb, remove the plus (+) cable from the battery, and touch one of the wires to the battery plus terminal and the other to the cable you removed. If the bulb does not light, you should be o.k. If it does, you have at least a 1 ampere current draw (maybe more)somewhere. To help find out where it is, turn off all circuit breakers and remove one end of all fuses in the distribution panel and the light should go out. Then turn the breakers back on and re-insert the fuses one at a time until the light comes back on. That should tell you where to look for the problem.

Good luck!   
Likely the battery has been "fried", as Karl suggests.  You may as well start with a new battery and then carefully monitor both the water level and loads for awhile.

Your RV may well have a substantial "parasitic" load on the battery - it is not unusual for it to be as much as 1-2 amps per hour in rigs with a lot of amenities. Propane and CO detectors, for example, draw some power at all times.  If it is too bad, you may want to install a battery disconnect switch.  The inverter, if left on, will also draw power even though there is no AC loads running, so make sure the inverter is off when not needed.

The typical Group 24 12V deep cycle does not have much capacity to begin with and about 40 amp-hours of load will discharge it to the point where it is unusable for most things.  If it will fit, try to get the slightly larger Group 27 size, which has about 20% more amp-hours.
Thanks folks. I can see right now that this forum's motto means what it says.  I'll be spending quality time with you in the future. :)
Glad to know you have enjoyed the Forum and that you plan to participate in future.  Many long standing friendships have been made here and we always enjoy making new friends.  The Forum has several rallies around the Country throughout the year,  where you can meet other members iin person.


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