Are my 31P-MHD chassis batteries dead, or just in a coma?

[Jean G]

We had never had any battery issues in the short time we owned our 2002 Dynasty, but she's been parked for a little over a year since I lost my husband/driver/maintenance crew and I'm trying to get her back on the road with a few very basic items so I can then decide the difficult question of keep or sell. Even plugged into 50 amps, it's not enough to maintain a charge, so I've added a battery charger, and still don't have enough to crank her up. She ran nicely in September with a jumpstart from the diesel guy since he was replacing the lift pump, but I really can't keep calling him. 🙃

Can these batteries be saved? If not, what's the most cost-effective replacement? I'm not in a big city, so I don't have a lot of retail options around here. I'd appreciate any suggestions or education you can give me. 🙂

[Marine Boy]

The battery in the picture has frozen and cracked.  Must be replaced and I would almost guarantee the other battery is not good.  Sorry, but you will need to replace the two engine batteries.   Don't know about the house batteries??

[Martinvz]

If you have a multi meter. Then check the voltage across the 2 poles, assuming it is not cracked. If the voltage is above 11.8V then you have a chance (about 60%, just my guess) with both of the batteries but anything less you are better off just taking these to the auto parts store and get replacements. 

[Tom Cherry]

5 hours ago, Marine Boy said:

The battery in the picture has frozen and cracked.  Must be replaced and I would almost guarantee the other battery is not good.  Sorry, but you will need to replace the two engine batteries.   Don't know about the house batteries??

BE VERY CAREFUL.  Do NOT get the cheaper 750 CCA batteries.  You need the SAME ones in the picture.  Interstate makes a 31P-LHD (presumably L for LOWER?? LOL).

The Interstates are a great cranking battery. Sometimes folks think that Costco or Sams will be cheaper.  MAYBE.  BUT, they also sell batteries that LOOK just like the current Interstates....but they are LOWER CAPACITY or LOWER RATED.  SO, you MUST be careful.  Your MH was designed to be cranked by TWO 950 CCA.  YES, you could get by with 900....but that would be the LOWEST.  

Sorry for the loss of your mate.  Know you have a LOT on your plate.  If there is anything that myself or another member can do...please PM or ask online.

We'll try to keep you going until you get the hang of it.

Good Luck...

[Jean G]

MB, that would go along with the extremely cold night we had last winter that probably did in that lift pump. Almost sent me back to NC, and I'm a Mountain girl. I'll expect the same of the house batteries, but they can be another chapter of this book.

Tom, thank you. This isn't the first time I've come here for help, and I'm sure it won't be the last. I'll be picking up my new batteries at O'Reilly this morning, and I'll know to check the CCA. My car guy ordered them for me, so I'm hoping they are exact match.

Next question - anything I need to look out for in doing the exchange? (Other than lift with my legs, not my back) Shut off the disconnect first. I'm guessing that I have acid all over everything that I need to clean up with baking soda? Clean the cables, maybe brush them out with a wire brush from my plumbing department, tighten them back so they can withstand the earthquake of rolling down the highway. Did I miss anything?

Will they be ready to go then, or they need to charge? I'm due at the tire shop at noon, or will I need to reschedule?

Most important - how do I keep this happening again? As cold as I thought it was, this was nothing compared to what happens regularly farther north.

Thank you all! 

[miacasa_2000]

Jean  Sounds like you have a good handle on it. Do all the things you said. If the battery tray is bad you'll have to make the call if you want to do something about it now and cancel the tire shop or take them back out later.  If yours is like mine you should have a battery maintainer for the chassis batteries that actually works off the house batteries that's maintained by your inverter/charger. Not sure if all that's working on yours but if it is I would disconnect from shore power as well before you start to remove the batteries and a rule of thumb is to remove the neg cable first and on installation attach the neg cable last. I live where it also gets very cold and never had a battery that was kept with the acid at proper level and fully charged ever freeze, part of the reason mine is plugged in all the time.

Roy Mercier  2003 Dynasty  

[Guest Ray Davis]

The generally recommended procedure is to take pictures of the battery cables, it's amazing that they look so simple but people get it wrong quite often.

Be careful with metal tools etc around the batteries,  they could still have lots of power that can melt metal or turn it red hot.

Those batteries are heavy, so help lifting would be nice to have.

Let us know how it goes.

[Bobkat11208]

7 hours ago, Ray Davis said:

The generally recommended procedure is to take pictures of the battery cables, it's amazing that they look so simple but people get it wrong quite often.

Be careful with metal tools etc around the batteries,  they could still have lots of power that can melt metal or turn it red hot.

Those batteries are heavy, so help lifting would be nice to have.

Let us know how it goes.

Along with this good advice, I would strongly recommend removing any jewelry, rings, etc. I have witnessed what can happen; it isn’t pretty. Just like a tool can turn cherry red if placed wrong, something on your body can also. 
Having said that, it truly sounds like you got this.