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bgoetting 11-24-2008 06:28 AM

Battery replacement
My '05 SMB, which I just got, has a 4d Lifeline AGM but doesn't seem to hold a charge well. The SMB was liquidated from an estate so it may have sat around unused for months. A few hours of driving will give me a reading of 11.7 V but drops within an hour of non-use to 11.1V. The 2000W inverter won't work unless I just finished a long charge (either by driving or by AC). When the battery is low, I can't invert even with the engine running, even tho the volt meter reads 13.5V (is that normal?). So looks like a new battery is coming my way so I am asking for advice.

How do I confirm the diagnosis that it is the battery and not the charging system?

Does everyone stick with Lifeline batteries, or are other brands OK too? Seems like the original batteries are not all that great since me and my only SMB-owning friend have both had bad Lifeline batteries with vehicles under 5 yrs old. I'm not sure I want to wait to special order a Lifeline battery.

Do I get this replaced at a RV store? Marine shop? I'm in Santa Barbara and I've seen there's a couple people from this area on this forum. Any advice which shop to go to?

From reading this forum, I see lots of us have solar panels to keep the battery charged. How much are these panels including installation? Looks like the panels alone are $1000+.

I don't use a lot of electricity. My truck camper had a $75 marine battery that was more than enough for me, worked for days, tho the frig was propane. I really need that inverter to power my blender though when my friends come over to my rig for margaritas. SMB was disappointing on my first camp out last weekend.

Again, thanks for the help.

yvrr 11-24-2008 07:30 AM

It sounds like the battery was allowed to get too low and now can't recover. AGM batteries shouldn't be allowed to discharge below 50% and it sounds like that happened. If it wasn't driven for quite a while and the propane detector was left on, that would do it. It should be able to charge up to about 13 volts after driving.

Give SMB in Fresno a call...they can give you a price to add solar and also the name of the batteries they are now using. I'd stick with a marine AGM battery for the time being. John Kalmbach mentioned to me a couple of years ago that they switched suppliers since the Lifeline batteries had gone up in price. You should be able to find a marine dealer in your area that has the battery you need and will install it.

BroncoHauler 11-24-2008 07:52 AM

Have you plugged in to shore power for any length of time to see if that will top off the battery?


jage 11-24-2008 08:11 AM

My batteries are toast too, more or less, from over draining. I'm choosing to ignore the situation as they still take a charge and I can get by.

Anyway, when the batteries were at 6-7v the shore power just faulted the batteries. I took the van out for a 3 hour drive, initially starting and forcing the Separator to ON once the van was started (probably not necessary).

After driving for 1.5 hours each way, turning the Seperator back to Auto when stopped and then plugging in while running, the shore power took over the charge and everything is back to topped off.

bgoetting 11-24-2008 09:23 AM

Hey Jage
I could also get by with a so-so battery except for the critical need for the inverter to work so frozen Margaritas can flow. My lights work fine tho dim. I can start the engine for the E-PH. Frig stops working after a few hrs, which sucks, but I always travel with a cooler full of ice anyway. I'm just not sure about needing a $500 battery. I think a small one would be fine, if it just worked! If I had solar, then a small battery would be more than enough.

I'm still surprised that the inverter doesn't work when the engine is running. I would think that there is enough current and voltage to run the inverter off the alternator output plus what ever is left of the battery.

jage 11-24-2008 11:05 AM

The margarita machine sucks down a lot of power... it isn't your invertor as much as the draw on it. But the invertor itself should be able to be on when the engine is running.

Also the fridge automagically runs in 110V mode if there is power on the outlets- so if your invertor is on you're running the fridge in less efficient mode during those times.

My lights are not dim- I would say that's a bad, bad sign. Off the cuff I would say it is a bad idea to keep pummling your battery, but I'm not sure what failures AGM are prone to exactly. That low it also has to mess with your separator system as whenever they are joined to the starter batteries, the system voltage probably drops. You could be costing yourself starter batteries in the long run.

I'd say it is worth having the AGM dropped and tested. A replacement should last for many years, and now that you own the van you can care for it properly.

Of course it is easy to spend other people's money, but my system is not nearly that bad, and when I replace I'll also be relocating the 2nd 4D underneath, which requires fabrication capabilities I don't have right now.

Jeffrey 11-24-2008 12:11 PM

You need a new battery. Do it. All your problems will go away and you can get rid of the ice chest. Isn't that why you bought the SMB?

jage 11-25-2008 02:25 PM


Awesome job! I moved your post:
Battery FAQ - Choose your battery problem!

and stickied it. I also locked it, so let me know if you want to make additions and I'll unlock it for you.

Again, good work!


John Kalmbach 11-26-2008 01:51 AM

It does sound like your Lifeline battery is bad. You could try to "equalize" it, you'll want to be careful to not harm the starting batteries or any electronics when performing the equalization.

You can get a direct replacement AGM battery from; . It is a group 4D with "L" terminals, see; .

I hope this helps.

John K.

bgoetting 11-26-2008 11:44 AM

Got the new battery yesterday, $570 installed. A non-sealed battery would be half that. I wonder if it wouldn't be better to get the cheaper battery and plan to change it every few yrs. I remember back when car batteries had open cells. You usually never needed to add water or acid until the battery got old.

Going camping this weekend with my high-maintenance girlfriend. We'll see how this goes.

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