Starter Battery Dilemma (1 Viewer)

Lenny HB

LIFE MEMBER
Oct 18, 2007
53,404
149,850
On the coast in West Sussex
Funster No
658
MH
Hymer B678 DL
Exp
Since 2008 & many years tugging
Not really a dilemma, as I fairly certain I am going to replace it, would be interested in a bit of feedback from the techies on here Raul ,autorouter etc.

Went out to the van to move it a couple of weeks ago, starter started to turn the engine over then the battery died & all lights went out on the dash.

Left it a few minutes then turned the ignition on to measure the voltage at the cigar lighter socket, not as good as direct on the battery but easy. The compressor for the air suspension started up and the battery voltage was 9.7v, after the compressor stopped battery reading was 11.2v gradually rising to 11.7v.
Left it overnight and it took some charge and was now at 12.55v & engine started fine.

My setup is 3 x 78 a/h Gel leisure batteries with 300 watts of solar via a Votronic 350 MMP regulator. Starter battery charging taken care via a CBE CSB2 relay which switches on when the leisure batteries are at 13.6v and off at 12.6v., and charges at up to 4 amps.
Mains charging via EBL 30 this only charges the starter at 2 amps, so I don’t normally plug in at home.

With the CBE relay and no draw on the leisure battery the starter battery should get a charge all day and probably 24/7 but to be sure I plugged the mains in and left it for two days.
Measured the voltage directly at the battery now at 13.55v.
Disconnected all charging methods and left it for an hour now at 13.1v

Left it with no charge and have been checking it daily. The system draw is approx 80ma (flips between 70 & 80 ma).
These are the results.
1616683035081.png

Today is Day 16, tried starting, started OK although turning over was slightly slower than normal but to be expected.
The Battery is 95a/h allowing for it being 4 years old it is probably down to 86 a/h.
The battery is down to approx 50% by day 13 by my calculations it should be at that level at around 23 days so looks like best to replace it.

My concern is why it went flat, we did have a couple of very rainy, cloudy weeks with virtually no solar input but the SB would have still got some charge via the CSB 2 relay.
One theory is the with the van sitting a while the air suspension compressor cuts in if the bellows lose pressure, the system is normally only live for 8 min after the ignition is turned off but I don’t know what goes on in the background.
The compressor draws 30 amp but normally only runs for a few minutes. I’ve emailed Goldschmitt but not received a reply.

I think I will replace the battery for the sake of a 100 quid not worth the risk.
I can get a Yusas 5000, 100a/h CCA 900A for £105 from Halfords with my trade card the standard price is £143 and Battery Mega Store are £113 so not bad. The original battery is 95a/h CCA 680A.

.
 
Last edited:
Apr 3, 2018
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think I will replace the battery for the sake of a 100 quid not worth the risk.
I can get a Yusas 5000, 100a/h CCA 900 A for £105 from Halfords with my trade card the standard price is £143 and Battery Mega Store are £113 so not bad. The original battery is 95a/h CCA680 A.
Lenny HB ....You be better of wi AGM!!!🤣🤣🤣🤣🤣🤣🤣

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SandraL

Free Member
Jan 24, 2012
1,373
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Hymer b694sl
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Since 2012 + Caravanner for 20+ years
You dont mention the leisure batt readings for the 16 days when you have starter batt readings decaying. A possibility is they are low so csb not trasferring charge, or perhaps the csb needs more than its specified 13.6v and is not operating.
Havent seen our van since early nov but in past 250 watts and votronic solar reg have kept both batteries up.
Assume your panels are not shaded.
Alternatively your air suspension is just greedy and needs disconnecting for layup, will that damage the bags if no air pressure and stationary?
 
Apr 26, 2015
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Ottershaw
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If you want to know what's happening to your starter battery I would suggest that you get a bluetooth battery monitor and download the app that goes with it, it will record up to 35 days history and display in a graph what charge and discharge voltages the battery has experienced whilst the monitor has been attached. I would imagine at 4 years old there is likely a fair bit of self discharge happening. 70 to 80 ma static drain is fairly normal these days I would think.

<Broken link removed>

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Bustup15

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Jun 25, 2018
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If you want to know what's happening to your starter battery I would suggest that you get a bluetooth battery monitor and download the app that goes with it, it will record up to 35 days history and display in a graph what charge and discharge voltages the battery has experienced whilst the monitor has been attached. I would imagine at 4 years old there is likely a fair bit of self discharge happening. 70 to 80 ma static drain is fairly normal these days I would think.

<Broken link removed>
And don't forget to add the extra drain from this device
 
Oct 14, 2007
3,985
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619
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Auto-Trail Mohawk
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16 fun filled years
If you want to know what's happening to your starter battery I would suggest that you get a bluetooth battery monitor and download the app that goes with it, it will record up to 35 days history and display in a graph what charge and discharge voltages the battery has experienced whilst the monitor has been attached. I would imagine at 4 years old there is likely a fair bit of self discharge happening. 70 to 80 ma static drain is fairly normal these days I would think.

<Broken link removed>
Interesting bit of kit, will certainly help with diagnostics. According to vids on you tube it draws 1ma
 
Apr 26, 2015
2,768
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Ottershaw
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And don't forget to add the extra drain from this device

1 - 1.5 ma it says, I actually use one of these just to keep an eye on my starter battery as I have a bit of parasitic drain that I can't track down (I suspect it's the alarm) but it doesn't make any noticeable difference to how long the battery stays charged for, the important part for the OP is that it will record when or if it's receiving a charge and when or if the compressor is kicking in and how often and for how long. It doesn't have to be attached for very long, a few days to a week should be long enough although that said mine is permanently attached at the moment.

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Dec 2, 2019
3,582
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If the draw in 80ma, then over 16 days is about 30,7ah. The voltage indicates half charged, so that’s a 61,4ah batter now, not 95ah anymore.
Time to change.
 
Aug 26, 2008
4,760
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since 2007
Lenny HB - crikey you were lucky your airbag ECU didn't decide to go Code B0100 due to low voltage. Mine went inop after only 10 days standing unused although the engine seemed to start OK on the first turn of the key. :madder:

My starter battery is also more than 4 years old. After charging at home via EHU, it rests at a steady 12.7v with no load, but after 6 days it drops to 12.6v. Until I have replaced that old battery the precaution I am taking is to charge it the day before driving. Even then on a cold start the voltage drops to below 10 before the engine fires up. Eeek - fingers crossed that the airbag ECU won't have another hissy fit. :rolleyes:

My less precise measurements are from the control panel rather than directly off the battery using a multimeter. Also I don't have any obvious drain such as a compressor. Or alarm.

PS - My 2 Banner hab batteries of similar age are probably in a worse state, dropping to 12.6v after one day, and to 12.5v by day 6. Very unimpressive considering nothing is powered off them while the van is standing on my drive. Thinking of replacing both Banners with a single Gel battery. [NB I must read the instructions for my charging unit first to check there is a Gel setting.]
 
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Lenny HB

Lenny HB

LIFE MEMBER
Oct 18, 2007
53,404
149,850
On the coast in West Sussex
Funster No
658
MH
Hymer B678 DL
Exp
Since 2008 & many years tugging
You dont mention the leisure batt readings for the 16 days when you have starter batt readings decaying. A possibility is they are low so csb not trasferring charge, or perhaps the csb needs more than its specified 13.6v and is not operating.
Havent seen our van since early nov but in past 250 watts and votronic solar reg have kept both batteries up.
Assume your panels are not shaded.
Alternatively your air suspension is just greedy and needs disconnecting for layup, will that damage the bags if no air pressure and stationary?
Leisure batteriesy fully charged up at over 13v.
If you want to know what's happening to your starter battery I would suggest that you get a bluetooth battery monitor and download the app that goes with it, it will record up to 35 days history and display in a graph what charge and discharge voltages the battery has experienced whilst the monitor has been attached. I would imagine at 4 years old there is likely a fair bit of self discharge happening. 70 to 80 ma static drain is fairly normal these days I would think.

<Broken link removed>
Not normally a problem happy to monitor it myself.
 
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Lenny HB

Lenny HB

LIFE MEMBER
Oct 18, 2007
53,404
149,850
On the coast in West Sussex
Funster No
658
MH
Hymer B678 DL
Exp
Since 2008 & many years tugging
If the draw in 80ma, then over 16 days is about 30,7ah. The voltage indicates half charged, so that’s a 61,4ah batter now, not 95ah anymore.
Time to change.
Yep I'm going to change, it's the reason it suddenly when flat that I can't puzzle out.
 
May 31, 2015
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Out of interest Lenny what brand is the cab battery..?

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Lenny HB

Lenny HB

LIFE MEMBER
Oct 18, 2007
53,404
149,850
On the coast in West Sussex
Funster No
658
MH
Hymer B678 DL
Exp
Since 2008 & many years tugging
@Lenny HB - crikey you were lucky your airbag ECU didn't decide to go Code B0100 due to low voltage. Mine went inop after only 10 days standing unused although the engine seemed to start OK on the first turn of the key.
I did have a bit of panic, when the dash lights went out and I turned the key back from start to on there was a great big seat belt warning sign on the dash I've never seen before, I thought oh no. After the battery received some charge not seen again, fingers crossed.
 

I2C

Feb 2, 2015
257
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A battery fully charged and not plugged in to anything will read 12.7-12.8v, thats it fully charged, 50% charged is about 12.4v. Once it gets below 12v it's basically knackered and time to replace as it won't hold a charge any more - these figures are rough, your milage may vary, and all with no load on.
 

pappajohn

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Aug 26, 2007
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172
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Good resting voltage but down on capacity.
Recently charged my lawn tractor battery as it wouldn't turn the engine over.
My charger has an option to show voltage or capacity.
Fully charged & rested... 12.7v
Capacity 80 percent

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Lenny HB

Lenny HB

LIFE MEMBER
Oct 18, 2007
53,404
149,850
On the coast in West Sussex
Funster No
658
MH
Hymer B678 DL
Exp
Since 2008 & many years tugging
A battery fully charged and not plugged in to anything will read 12.7-12.8v, thats it fully charged, 50% charged is about 12.4v. Once it gets below 12v it's basically knackered and time to replace as it won't hold a charge any more - these figures are rough, your milage may vary, and all with no load on.
For a flooded cell 12.2 is nearer 50%.
1616692559559.png
 
Last edited:
Apr 27, 2016
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It looks to me like the arrangement to keep the starter battery topped up is not working. This may be either a faulty CSB2 or the voltage not getting up to the turn-on voltage threshold. You could do some tests to see what the turn-on threshold actually is.

If the CSB2 is working as designed, then maybe a different trickle-charger will do better - one without a voltage threshold, maybe.
 
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Lenny HB

Lenny HB

LIFE MEMBER
Oct 18, 2007
53,404
149,850
On the coast in West Sussex
Funster No
658
MH
Hymer B678 DL
Exp
Since 2008 & many years tugging
It looks to me like the arrangement to keep the starter battery topped up is not working. This may be either a faulty CSB2 or the voltage not getting up to the turn-on voltage threshold. You could do some tests to see what the turn-on threshold actually is.

If the CSB2 is working as designed, then maybe a different trickle-charger will do better - one without a voltage threshold, maybe.
Relay is working fine, the first thing I checked. Just a bit strange why the battery suddenly went flat.
Picked up a new Yuasa battery today just got to get around to fitting it and it will be monitored closely.
 
Aug 31, 2009
148
159
Near Long Stratton, Norfolk
Funster No
8,241
MH
Carthago C line
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25+ years
Lenny HB , just wondering why you don't use the trickle charge from your Votronic regulator to starter battery? I have 200 watts solar and a 250 Votronic regulator, and starter battery is always showing 12.9 -13.0 v. Original battery, now over five years old.

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Lenny HB

Lenny HB

LIFE MEMBER
Oct 18, 2007
53,404
149,850
On the coast in West Sussex
Funster No
658
MH
Hymer B678 DL
Exp
Since 2008 & many years tugging
Lenny HB , just wondering why you don't use the trickle charge from your Votronic regulator to starter battery? I have 200 watts solar and a 250 Votronic regulator, and starter battery is always showing 12.9 -13.0 v. Original battery, now over five years old.
The Votroic is only a 1 amp charge rate the CBE relay charges at up to 4 amps and if the leisure batteries are fully charged it will carry on charging the Starter battery long after the sun as gone down.
I actually fitted it because I happened to have one around but it is a much better solution.

I was surprised at it failing after 4 years, last van I only had 3 years that was still fine but the one before the starter battery was still fine at nearly 6 years old. Others have had them fail at 3 years in Ducato's.
The battery is not completely knackered but has lost a fair bit of capacity it probably would go on for a year or more. Not worth the risk for the sake of a hundred quid..
 
Last edited:
Dec 2, 2019
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All I can think of, is corrosion keeping it charged all the time with little discharging. When a battery degrades gradually, it’s a sign of sulphation. When goes of the cliff, usually is corrosion or terminal fault inside.
 

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