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Chumley 08-23-2015 03:44 PM

Re: My SMB Sprinter Van conversion building experience
Thanks Dave,

I did turn off the main power but I can't get to the batteries without taking the folding couch/bed apart since they are under it. I don't have the time nor patience right now and I'm battling a severe case of frustration too...

I may have to talk to SMB about replacing the batteries now.

What do you guys think? Too much to ask for?



daveb 08-23-2015 05:07 PM

Re: My SMB Sprinter Van conversion building experience
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My guess is the shop that put in your Optima batteries do not know the difference between a spiral wound battery and a standard AGM. Unless you actually requested a typical wet cell, I've never seen SMB go to the hassle (or cost) of ordering a specific deep cycle wet cell type battery. The common battery used by them these days is a Universal brand 4-D AGM battery but I don't have a clue what you ordered. They buy so many of the UB4D's I'm sure they get a cut in the average cost and sell them at the listed price + installation.

On most builds the house battery positive wire runs to a standoff stud where the inverter positive terminal lands. Also it's possible the positive distribution lead from the 12v fuse box lands there as well. There will also be a lead from the separator going to that stud. I've seen some builds that use the separator itself as the standoff stud but that's not common. The wire from the house battery system is always "hot", so if you disconnect it, you must keep it insulated and covered as the lead must not touch ground while it's off. Obviously if you can get to the battery lug and disconnect there that would be best but usually the battery box is difficult to all depends on battery access. Now if for some reason there is a large amp fuse inline, pulling the fuse would be a simple task but again it depends on if even there is one and where the fuse holder is located.

As to why you're loosing battery reserves, it may be a number of problems.

Something is on pulling a load. This can be checked with a good clamp-on amp meter on the main buss wire coming from the house battery. All it takes is something left on while there is no charge coming in. I take it you have no solar?

There is a short somewhere (but I doubt that). Usually you'd know if there was a short but I have seen pinched or abraded insulation on a wire going to ground that cause an intermittent problem.

The separator set in an open position would not allow the alternator to charge the battery. If it's stuck open, been tripped or purposely set to the open position the battery would get no charge from the vehicle running. But in that case the shore charger should have brought the battery back up when plugged in.

You have a bad connection at the battery/batteries or somewhere along the system.

You have a bad battery. It happens. And since you've stated you are using Optima, I can't believe you only have one. If for any reason you have one bad battery in a bank (group of batteries connected to each other to form one large battery), one bad battery can easily take down its mates in a hurry.

I'm also guessing you have a multi stage charger/inverter. If a AGM is taken too low, standard car chargers might not bring it back to life. The deal is your alternator should, so unless you have more than one issue going on I doubt it's a shore charger issue alone.

I'd find the separator and test voltage on both sides with the engine off, with it running, and with the engine off but the shore charger on the charge mode. The engine and shore charger voltage will be between 13-14.6. Voltage from the starting battery with the engine off should be about +/-12.7 If you have a good inverter/charger it should have a gauge on it and I'm guessing that is what you're using to determine the battery voltages??? Or are you using the little plug in volt meter that came with the van?

Sorry you're having problems. If you do get the batteries disconnected at the battery terminal(s) get a charge on it/them ASAP.

Good luck on your troubleshooting.

Chumley 08-23-2015 05:40 PM

Re: My SMB Sprinter Van conversion building experience
Hello DaveB,

I can tell you that I don't know anything about a spiral wound vs standard AGM (you aren't saying lead/acid with plates vs. AGM (absorbed glass matt) are you?). Fact is that I am not the strongest at electrical systems. Either way SMB checked the batteries themselves and the settings on the charger so according to them all was okay.

The batteries (2) are now down to 7.8 volts according to the inverter/charger. When are they toast?

The generator message light is blinking so someone at SMB tried to start the generator and didn't reset the generator after it didn't start. Doubt it draws that much but I will reset that now.

I'm waxing the beast right now due to tight time constraints until we leave on our trip. I'm not prepared to start taking things apart.

All of this is a shame because I left SMB Friday giving everyone a big hug and smiling as I left because everything looked great on the surface. There are other issues I'll bring forward after a discussion with SMB in the morning. All I know is that I drove in Monday, gave them a list of requests and then picked it up Friday. I didn't know that I would have to do a full inspection of the entire system when I got home.

This just sucks. Good news is that I prepared far enough in advance that we should not have any trip ending issues if SMB jumps on the issues right away.

So, I know that I have paid a premium in the past for Optima batteries so if they are toast should I hold out for another set?



daveb 08-23-2015 06:14 PM

Re: My SMB Sprinter Van conversion building experience
Probably not but I would want to find out what the cause was. It would be easy for the shop that installed the batteries to have even made the mistake.

I'd ask SMB if they dropped each battery and did a bench load test on each. Most testing is only done by testing voltage and if the batteries were up at the time they would have passed the test. A load test is a different thing.

Have them reinspect the connections and make sure the separator has not tripped or been set to manual open if you have that model.

I'm not understanding why your inverter/charger is not bringing them up but they may have to be charged in a particular procedure... you can read about here: ... rticles/#3

Don't toss the batteries, I've brought several back from the dead but in one situation nothing I did worked and that was due to the battery being bad from the get-go. It never lasted over 2 months and there was no reason why it just dropped in voltage. You can read about a deeply discharged battery in the link and what can be done about it.

Scalf77 08-24-2015 10:47 AM

Re: My SMB Sprinter Van conversion building experience

In both vases now your battery may be so low that
A) the inverter/charger won't charge the battery, or
B) the battery separator won't connect. If it is a the Blue Sea ACR , it definitely has a 9.6 volt lock out setting.

If you have the 7622 you should be able to manually combine them with the yellow knob. If you can tell me what Inverter/charger you have , I might be able to help out on that.


Chumley 08-24-2015 12:29 PM

Re: My SMB Sprinter Van conversion building experience
Good morning,

I went out and checked the battery level and they are down to 4.6 volts. Something is really drawing them down and nothing is on and the main power is off. Only the smoke/carbon monoxide/propane(gas) alarms are on.

I did get the shore power to fire up the charger now. Not sure what the issue was yesterday but maybe the GFI tripped when I plugged Charlie in (I hit reset before double checking because it is deep in the back of a cabinet so it's hard to see if it has tripped).

So one issue down.

Now where is this load coming from and how come he doesn't charge from the alternator?

What I had SMB West do at the visit:

1. Check the batteries and the charger setting since I didn't think that the batteries were holding as good a charge as before. This may actually have been a case of me paying more attention to the voltages since the batteries were new and I was working on the generator issue and the generator doesn't like lower voltages to start - does that make sense? SMB said the batteries were Optima and the settings were fine I was told.

2. Check the routing of the power for the generator starter. There is some conflicting info from the manufacturer who told me that the starter motor for the generator needs to be connected to the chassis battery. This makes sense since the generator doesn't like low voltages for the starter and you expect the coach batteries to be low when you start the generator if you are using it to charge the batteries which is our primary use. SMB confirmed that the connection was on the coach batteries.

3. I had a new subwoofer installed up front along with a switch that controls which subwoofer (front or rear) is on and also a volume for the new subwoofer. I don't know where the power is connected but the stereo was off and so was the coach power.

I just spoke to the shop that installed the Optima batteries and worked on the generator issue. They are recognized locally as the go-to shop for RVs even though they are an auto shop. We have several RV dealers in town and they take their problem jobs to him. A friend of mine who got one of the last Monaco motorhomes before they closed their doors (albeit only temporarily) got a motorhome that was cobbled together without a lot of care. It took some time but this shop went through the whole thing and fixed it all. My friend thinks they walk on water now.

So I am now waiting to hear from Sportsmobile on what they plan on doing next. I want to work with them because they have stood behind everything that has happened in the past but they said they do not want to talk until they do their research.

Charlie is on shore power and the charger is indicating that it is charging. Maybe the charger is capable of bringing them back but need to talk to SMB about that.

I guess Iíll need to be sure of a few things:
1. Will the shore power resuscitate the batteries?
2. What is creating the unusual draw?
3. Just how low can I let the batteries go on a trip before they canít be recharged by the alternator?
4. Was the low voltage on the batteries (9.4 volts) the reason the batteries didnít charge on the alternator?

Right now Iíll wait until SMB calls and tells me what we can do to get this all fixed before I travel to Alaska.

I donít want to knock SMB because they are trying to help me get Charlie ready but something along the line went wrong. I donít know what it was and I just want to get it fixed.

Looking forward to a fix.


Scalf77 08-24-2015 02:12 PM

Re: My SMB Sprinter Van conversion building experience
Your best bet would be to take it back to Sportsmobile or the other RV shop. A competent technician should be able to come to a reasonable solution.

You may be able to charge your battery back up and it may survive the severe discharge. You have definitely taken some life out of it. If it does not work reasonably then you could try a equalizing charge, you would need to refer to you charger and battery specs and or manuals.

Not sure what your unusual draw is, you have only specified that it was low on voltage. I understand that something is pulling it down, but without know when and what it was charged to it is hard to make a prediction as to unusual draw. It does sound like it is possible that it went below the cutoff point for and that maybe the separator was in lockout mode. After that everything will keep discharging, and only get worse. So it is possible that once you the battery above that voltage the alternator may work. Again, a lot of that depends on what unit they put in for a separator. It is also hard to estimate how long your battery may last, without know the size of your battery bank, I see you have two, and what appliances you have specifically the refrigerator draw, as it would because if was left on unexpectedly, the draw down may be big, especially in hotter temperatures.

I highly recommend a good battery monitor, either a traditional amp counter like Xantrex Link Pro , Victron energy BMV, or a Balmar Smartgauge.


Viva 08-24-2015 02:48 PM

Re: My SMB Sprinter Van conversion building experience
First of all, I just wanted to say that I have appreciated your detailed build thread. I'm glad to hear you are enjoying Charlie and your trip to Alaska sounds great.

I don't understand exactly what is happening with your batteries right now. I mean, I see the results, but I don't know exactly why because there is not enough information (not your fault). A few different scenarios could fit, but there's not a way from here to tell which one.

I would not be happy with any batteries of mine (much less expensive new ones) ever seeing anything even remotely close to 4.6 volts. I'm pretty sure that's going to compromise them (even if you can resurrect them). So, first of all of course I would want to figure out the problem; second, I would want to correct it; and third, I would want to find out if it was anyone's fault (and if so whom) -- not because I'm into assigning blame, but because it would only seem fair that that person replace the batteries (or somehow take responsibility).

I would also absolutely follow Scalf77's recommendation for either a "counter" type battery monitor (Victron BMV, Link, etc.) or a Balmar Smart Gauge. I actually have both (Victron plus Smart Gauge), for a few reasons: One is they are complementary in their functions; two is that I like information; and three is that although they are not cheap, it's easy (for me) to justify even a few hundred dollars in expense when AGM batteries are so expensive (I have three, and they were each around $375). All I have to do is "save" one battery, one time, and I've paid for both monitors (more likely in the real world, I may be able to prolong the life of all three by X amount of time - here's hoping anyway).

Basically, the Victron/Link type will show you extremely accurately how much power (amps or watts) is going into or out of your batteries at any one time. If you have more than one thing running, you can trouble shoot by changing things and watching the gauge. They also show you state of charge (SOC) in percentage, but the accuracy is somewhat dependent on how you program it, how the batteries age, and other things that you can't always know.

The Smart Gauge uses some amazing algorithm, plus samples the voltage ninety-jillion times per something, and gives you SOC. Very accurate, nothing to re-set as batteries age, just SOC pure and simple. It also shows voltage (as does the other one), but this is only meaningful sometimes (batteries in resting stage, or to see what a charger is putting in, etc.).

The Victron type are not hard to install, but do involve putting in a shunt (so some slight wiring rearrangement) plus programming in some factors from your batteries, and adjusting as they age.

The Smart Gauge is two (small) wires, one to a positive terminal and one to a negative terminal and that's it.

I'd be hard-pressed to choose between them as they are both great for some things. I guess I'd go with the Smart Gauge.


PS: It would be nice to know what sort of separator you have (for example, Blue Sea 7622) and if it can be manually locked out (some can for when you work on things), and whether it IS locked out.

Chumley 08-24-2015 05:40 PM

Re: My SMB Sprinter Van conversion building experience
Thank you everyone for the recommendations.

The thing is that before last week I never had any problems with the batteries so never paid much attention to them. I know that on a trip we can usually run 2-3 days on battery power (typically cool weather so the heater works a bit) and then I need to fire up the generator to recharge them. We have an Isotemp refer which is very efficient and then we use the lights, TV/radio, heater and maybe turn on the inverter to use the microwave from time to time. 2-3 days on that kind of load.

I did speak to Peter at SMB West and I think we have an understanding of what might have happened and what the next steps are.

Charlie arrived home after the long drive at about 12.4 volts instead of the usual 12.7 Ė 12.8 volts likely due to the refer & water pump being on and me blasting the stereo (long test of the new subwoofer). Okay, Iím good with that.

Seeing the volts drop to 9.6 by Sunday morning, because of the refer & water pump (likely no load since there was no demand for water) being on, makes sense. Being below the normal charging threshold for the alternator to charge makes sense.

Dropping to lower levels because the batteries are in decline makes sense so it being 4.6 volts this morning even with the master switch being turned off (all alarm/detectors are still on). Maybe there is no additional excessive draw and the batteries were past their performance curve on delivering power. Makes sense.

So we will wait to see how the batteries charge overnight and then I will monitor them on the drive to the dealership. If the voltage drops on the drive to the dealership instead of increase then there is a problem for sure.

Peter says that if the batteries do not come back then I should take them back for a warranty replacement because they should come back.

As you can well imagine the weeks before a long vacation tend to be a bit eventful and busy getting ready to clear out of town. I need to confirm the battery condition and any needed resolution as soon as possible since Charlie will go to the dealer for the major service, tire shop for 4 new tires, and then the whole generator repair issue. Doesn't leave me a lot of time for getting Charlie's battery issue taken care of if it is outstanding - but can't go on the trip without it resolved.

So enough about the stressful stuff.

How about a little of the good stuff that got taken care of recently.

One of the main blinds broke a cord and was flopping about. SMB West fortunately had a couple in stock and were very kind in pricing since I decided to replace both main ones in the rear so they would match. Thank you SMB.

The guys at SMB washed Charlie which was a big deal to me. Where I live we can't wash cars due to the drought so that was a big deal. With that I got to wax the big guy which he really needed and wanted to do before 3 weeks on the road. I also started putting 303 Protectant on all of the rubber and vinyl parts. I stand by this stuff and I feel much better knowing it will be done before a long trip.

Having the stereo fixed by adding a new subwoofer is just what we were looking for and will allow us to crank the music and not deafen our dogs.

A full alignment and installation of new rear shocks makes me feel good and with four new tires going on next week we don't need to worry about Charlieís shoes. The old set of tires may have survived the entire trip but it would be an iffy proposition. Of note is that the replacement tires we put on the fronts (Michelin LTX A/T 2 since one of the original Contis was defective) far outlasted the rest of the OEM Continental mud/snow tires. The Michelins have a more aggressive tread pattern so should do well in any weather we may experience. Amazing how much better they lasted compared to the stock Contis, they look new in comparison at just under 19,000 miles on all tires.

So I think I feel good about everything but it sure does seem that these things always happen around a visit to SMB so maybe Charlie has the same response that some do to a visit to the doctorís officeÖ

For now I am hopeful that all issues are in the past.



daveb 08-24-2015 07:07 PM

Re: My SMB Sprinter Van conversion building experience
A couple things come to mind, one is I would think the installer had enough common sense to wire the stereo amp to a switch if it doesn't shut off automatically and if not, you turned off the switch when the van sits if it's wired to the house batteries, second I'm guessing you didn't go from a 200ah battery to a set of 55ah optima's... what amp hours are the new batteries and how many did they put in? Also I hope you followed the link on how to recharge a deeply discharged optima. I'm sure SMB will find the problem and will test the separator but I also hope they understand how to recharge a deeply discharged AGM...I'd think so. The root cause might be as simple as the amp not wired correctly, but that is just a guess on my part. Like I posted it's very possible more than one thing is going on like the separator tripping open compounding the problem.
X-2 on gauges... they at least point you in the right direction. You need need to make sure you never draw the batteries down below 12.2 resting voltage on a regular basis.

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