Melted battery lead (Urgent)

lexi · Post by **lexi** » 27 Dec 2009, 16:17

I remember there was a whole load of Alternators frying batterys a few years back. Lets just say it was a factory in Wales

Least you got to the bottom of it although a bit more costly than a loose Earth.

deian · Post by **deian** » 27 Dec 2009, 16:17

After seeing those photos I would say the alternator needs a new regulator. Thats mad damage, I wouldn't run it until the problem has been sorted tbh, incase the battery explodes.

The battery is just the buffer between the cars electrics and the alternator, and most items can run at over the 12v needed (batteries output to 14.4v usually), because the battery will dampen the current it's voltage won't go too high, but the current into it will, hence the melting. Ouch.

To be on the safe side afterwards, get a new battery.

Post by **Peter.N.** » 27 Dec 2009, 16:55

Got there eventually

Post by **CitroJim** » 27 Dec 2009, 17:05

deian wrote: To be on the safe side afterwards, get a new battery.

Yes, it may seem Ok but it'll die soon. Many years ago I had the regulator go short circuit on my Renault 4 and that boiled the battery despite the car only having a little dynamo. I only knew it had happed by the smell! The dynamo was red-hot and the battery fairly seething

Anyways, the battery survived for two days afterward and then, nothing, not a sausage...

Xantidote · Post by **Xantidote** » 27 Dec 2009, 17:49

Well, new battery, replacement alternator, and new cables in vicinity of the battery. Hopefully the other cables/wiring are OK as no fuses blew. The high voltage may have shortened the life of any bulbs that were on at the time.

On the bright side, you've not got a bill for breaking down on the motorway and having to be towed home -

deian · Post by **deian** » 27 Dec 2009, 18:07

I don't think a new alternator is needed IF you the regulator is replacable on that particular unit.

Something tell me the bulbs and things will be ok, the battery was a buffer and the voltage didn't out go high enough for them to blow the bulbs etc. The fuses would have gone first I would say.

Xantidote · Post by **Xantidote** » 27 Dec 2009, 18:20

[quote][/quote]

Ok, fair enough, replacement regulator probably OK.

The battery may bay acting as a buffer, but anything switched on at the time would be operating with 20 rather than 12 volts - very effective at de-icing the rear screen!

deian · Post by **deian** » 27 Dec 2009, 19:02

The reason your cables melted was because they were sucking up the power rather than the end item, so I wouldn't assume everything was operating at 20 volts.

scoles · Post by **scoles** » 27 Dec 2009, 19:07

thanks for that guys looks like i found the problem.

I was aware that petrol regulators ran at 14.4 volts but wasnt sure if the diesel ran higher to compensate for higher cranking amps or such.

Is it possible to replace the regulator on its own? if so where can i find it?

Also how am i able to prove for a fact that this is the problem?

Cheers
Stuart

deian · Post by **deian** » 27 Dec 2009, 19:28

if when you test the voltage across the battery at rest it would probably be around 12 or 13v, if when you start the car, the alternators provide the power and recharge the battery, so naturally if the voltage is higher across the car then it would show this on the battery too, so something on the alternator isn't regulating the voltage output.

as for whether the regulator is changeable is dependable on the alternator, MAYBE if you have some details of the exact car and year, someone may be able to tell you which alternator it has and therefore whether the regulator is interchangable

scoles · Post by **scoles** » 27 Dec 2009, 19:36

the voltage is varying when the car is running. between 16 volts and 20 volts.

the car in question is a citroen xantia 2.0 HDi saloon on a X 2001 plate.

So if anyone can shed any light on the alternator and regulator situation then please do let me know.

Thanks
Stuart

Post by **Peter.N.** » 27 Dec 2009, 20:15

The regulator is obviously the problem, what's happening is that the alternator is running flat out, it would probably only be a short period of time before it burnt out. A secondhand alternator would probably be the cheapest way. There are new ones on ebay from about £30.00 but you would have to check suitability. You could probably get a new regulator but it would probably cost as much as a s/h alternator

deian · Post by **deian** » 27 Dec 2009, 21:14

ahh yes, i change my mind now, a new alternator would probably make more sense

bxman · Post by **bxman** » 28 Dec 2009, 12:33

I am intrigued by the sugar like granules in the photo.
Are they small balls of copper?

It looks like a dry/loose/high resistance battery connection that could well have been sparking for some time. I suspect the intermittent loss of battery connection (capacitance) may have caused the regulator to short out whatever else no-one can say the alternator and it's belt were not up to the job.

If you post a photo of the regulator and PM me your address I will willingly send you one for the cost of the postage.

Off subject for a second can anyone explain why the second page of this post fits my screen while the first one does not.

Good Luck, Thanks and a Happy New Year to everyone

Patrick

Assorted Xantia

scoles · Post by **scoles** » 28 Dec 2009, 12:46

bxman wrote:I am intrigued by the sugar like granules in the photo.
Are they small balls of copper?

It looks like a dry/loose/high resistance battery connection that could well have been sparking for some time. I suspect the intermittent loss of battery connection (capacitance) may have caused the regulator to short out whatever else no-one can say the alternator and it's belt were not up to the job.

If you post a photo of the regulator and PM me your address I will willingly send you one for the cost of the postage.

Off subject for a second can anyone explain why the second page of this post fits my screen while the first one does not.

Good Luck, Thanks and a Happy New Year to everyone

Patrick

Assorted Xantia

Hi thanks for the input bud,

I thought the regulator on these couldnt be replaced and in fact it had to be the whole alternator unit?

Cheers
Stuart

French Car Forum

Melted battery lead (Urgent)

subject

Re: subject