House batteries down

PhilV · 06-06-2020, 12:29 PM

I have a 2017 Journey and it is under covered storage in AZ. IT has been in storage for several months due to the virus problems around the country. I have run the engine and generator several times but it had been 5 weeks and a lot of warm weather since the last time. I went and the engine kicked right on but I got no lights on the coach battery disconnect for several minutes. I tried to start the generator and it did a quick turnover and died. I ran the engine for about 20-30 minutes, primed the generator but the same result. I figure I will go out the next couple of mornings and run the engine for 45 minutes to an hour each day and then see if that builds the batteries up enough to start the generator. There is no shore power close. Anybody agree or have other thoughts?

Phil

Morich · 06-06-2020, 01:06 PM

I suspect it is a simple matter of rundown batteries if there was not something done to maintain them.
However, it takes some looking or knowing which batteries do what on your specific RV as there are some difference on different RV. On those I'm familiar with, the start/ engine battery is what is used to start the genset. One reason for me to alway start the engine before doing any of the operations that take lots of power like slides, jacks or start the genset.
If you RV uses the house batteries to start the generator, it may also use those batteries to move the solenoid which ties start and coach batteries together when the engine is running. I read of some cases where the one set of batteries being too low keeps them from being tied together to charge from the engine alternator.
I would first want to know that is not happening by putting a good charge on both sets, just as an easy first move.
With a meter on hand (almost required for my RV use!) I would look at the voltage on each set to see what that tells me.

Winterbagoal · 06-06-2020, 02:04 PM

Agree. If the batteries are GC2s or similar, and are true deep cycle, you might get them back up, but too many other factors involved to say for sure.
30-45 minutes of engine run time probably won't do as much as shore power and a proper charger/maintainer, but sometimes you gotta go with what you got.
Worst case scenario, you're replacing some batteries.
How many batteries? Could you take them home with you, and charge them with shore power and a smart charger?

Goodspike · 06-06-2020, 02:07 PM

Is it possible to jump start the generator?

**creativepart** · 06-06-2020, 02:19 PM

If your House batteries are dead in storage it's possible that you left the house battery disconnect on. And, it's also possible that they were near dead when you put them in storage and were not aware of it.

Then they died the rest of the way, and if Flooded Lead Acid (6v or 12v) the extended period of them being discharged could have ruined them. It's not a given, but it's certainly a possibility.

You might be surprised but to fully charge FLA batteries can take many hours. Sometimes 24 or more hours. And, if they've sat dead they would sulfate and either not be recoverable at all OR take a great deal of special work to recondition them.

Have you checked the acid level in the batteries yet?

Winterbagoal · 06-06-2020, 02:44 PM

I'll add, if you're going to replace them, consider LiFePO4 as an option. Same amount of power at half the weight. Many more charge/discharge cycles than FLA, more even voltage level during discharge, they recharge much faster, and you can draw them down to 20% remaining without doing them any harm. You can take them down to 0%, as long as you recherge them fully right away, without harming them. The best brands are virtually idiot proof, with built in BMS systems that keep us humans from breaking them. Trust me on that one.

If the budget can handle it, of course.