Technical Sudden battery failure

[Anthony489]

Driving around one day last week in the 2009 X250 motorhome, starting and stopping every half hour or so with no problems. Stopped for 3 minutes, came to start again and absolutely nothing doing - battery down to about 6 volts and instrument needles jerking. Rescued by the AA who gave me a jump start (Their booster pack couldn't turn the engine, had to get their big jump leads out ). Had to drive 5 miles to the campsite knowing that stalling or switching off by mistake would leave me stranded. Next morning needed another jump start to get me to the garage for a new battery. This needed two sets of jump leads in parallel to get the engine to turn over, then all fine. Garage swapped battery with the engine running ! Moral of this tale - if you carry anything other than really beefy jump leads they won't be much use unless your battery still has some life in it. Also, the steering is incredibly heavy if the engine isn't running (had to push the van closer to the donor vehicle). In the past I have always had tell tale signs that a battery was getting tired, but this one was fine and always turned the engine over vigourously until the day it died.

 

[varesecrazy]

Driving around one day last week in the 2009 X250 motorhome, starting and stopping every half hour or so with no problems. Stopped for 3 minutes, came to start again and absolutely nothing doing - battery down to about 6 volts and instrument needles jerking. Rescued by the AA who gave me a jump start (Their booster pack couldn't turn the engine, had to get their big jump leads out ). Had to drive 5 miles to the campsite knowing that stalling or switching off by mistake would leave me stranded. Next morning needed another jump start to get me to the garage for a new battery. This needed two sets of jump leads in parallel to get the engine to turn over, then all fine. Garage swapped battery with the engine running ! Moral of this tale - if you carry anything other than really beefy jump leads they won't be much use unless your battery still has some life in it. Also, the steering is incredibly heavy if the engine isn't running (had to push the van closer to the donor vehicle). In the past I have always had tell tale signs that a battery was getting tired, but this one was fine and always turned the engine over vigourously until the day it died.

FYI , battery cells give 2 VOLTS each.

3 sells in a 6 volt battery ,

6 cells in a 12 volt battery.

you'd obviously lost some cells..

basically a "booster will only have enough power to "top-up" a failing 6 cells,

if you've "LOST" 1 cell - it's trying to top up the missing 2 volts form a MUCH SMALLER batteries 2v cell..,
that's just about o.k. on a little petrol engine.. no chance on a big diesel.

 

[cris1117]

Hi. Modern batteries give little or no warning they tend to just die instantly.

 

[Crossingkeeper]

I had a very similar experience at the beginning of the month though I had to drive from North Wales to Norfolk without stalling or stopping the engine; by great good fortune I'd filled up with diesel a couple of days previously, phew!

However it never occurred to me to fit the new battery with the engine running....though nothing untoward seemed to happen through the electronics being disconnected.

As a consequence I bought one of those glovebox-sized starter booster packs (supposedly suitable for diesel engines up to 2.5 litres) ensuring that I will probably now never need it

 

[Deefordog]

We had similar hot starting problems and the symptoms of flickering dials. We put it down to the usual bad earth strap (replaced it with two cables) but also replaced the starter battery as a precaution.


Strange thing was that when the dials flickered and the engine wouldn't turn over without lots of clicking, disconnecting the starter battery for a few seconds and re-connecting got the engine started as if there was nothing wrong.

 

[varesecrazy]

I had a very similar experience at the beginning of the month.

However it never occurred to me to fit the new battery with the engine running....though nothing untoward seemed to happen through the electronics being disconnected.

As a consequence I bought one of those glovebox-sized starter booster packs (supposedly suitable for diesel engines up to 2.5 litres) ensuring that I will probably now never need it

With the amount of expensive electronics on any modern vehicle..Id be deeply concerned about taking the battery out of the loop.

Charlie

 

[corcai]

With the amount of expensive electronics on any modern vehicle..Id be deeply concerned about taking the battery out of the loop.

Charlie

Yep battery is an essential part of regulation, whuch is why boats have field disconnect switches in case the battery switch is thrown while running. Youre extremely lucky to get away with it. if your unlucky it can let the magic smoke out of the alternator if you're more unlucky it can let the magic smoke out of everything else.

 

[Crossingkeeper]

Yep battery is an essential part of regulation, which is why boats have field disconnect switches in case the battery switch is thrown while running. Youre extremely lucky to get away with it. if your unlucky it can let the magic smoke out of the alternator if you're more unlucky it can let the magic smoke out of everything else.

Hmm...that might explain why the cells (in the now expired battery) which were inaccessible without removing the terminal plate were low on distillate; which in turn might explain the failure.

So I seem to have got away with battery disconnection twice however if there is a next time I will stick my new booster pack on the jump start terminals to be on the safe side.

 

[CDK]

My Ducato and my Kia Sorento are roughly the same ago.
The Ducato has consumed 3 starter batteries, the Kia only one (and the old battery is still used in a solar system).
The secret is in the voltage regulator: the Kia (Hitachi) alternator is limited at 14V and has temperature compensation, the one in the Fiat reaches 15V at any temperature. Unfortunately a better alternator for a Ducato is not an option.

 

[corcai]

the one in the Fiat reaches 15V at any temperature. Unfortunately a better alternator for a Ducato is not an option.

15v is too high, which alternator do you have. There are several alternators available, the highest setpoint is 14.7v which would be fine with a calcium battery in our climate but probably too high in sunny croatia. The standard bosch alternator is 14.2 / 14.4v setpoint

 

[CDK]

I fully agree corcai, but out of curiosity I measured voltages in both vehicles and noticed the differences. To make things worse the Ducato battery sits in a closed compartment under the floor, with an isolating rubber layer on top of it. There it silently cooks dry from overcharging.