Generator Failure?

[ola]

Hi all,

 

My car stopped suddenly and couldn

[mumof4]

Umm..i take it you mean the main fuse feed box melted a tadge????(one under the bonnet)

 

If so..when you replace the fuse/box..(only 20 quid i think)....replace the main black cable aswell...alternator one i think it is..Its happened to a few of us on here..myself and dingo included.Second time mine went..so did the alternator!

[ola]

Yes you

[mumof4]

I assume you have replaced the fuse already?????

 

I believe you need a voltimetre to test the Alternator...i could be wrong as ive never tested one.Someone better than i can answer that question for you...start simple and work up..replace the fuse/box..i would advise to replace that cable aswell......if no joy...try trickle charging the battery..(what type have you got??)..if still no joy..next look to the alternator.

Touch wood that it is ok.

[seatkid]

Now, any great ideas of the cause?

 

When you replace the fuse box check the voltage from the alternator, engine running at around 1500 rpm, no load (lights etc). If the voltage is above 15.0 volts, then the voltage regulator in the alternator is faulty and the alternator is cooking your battery with mucho current. On the other hand if the voltage is below 13.0 volts, then a faulty battery could be the culprit, demanding too much current.

 

It could have been down to loose connections in the old fuse box, causing a lot of heat where the connections are.

 

If you're happy its none of these then check the outgoing cable after the fuse for evidence of a short to chassis.

[ola]

Encourage with your answers, I

[mumof4]

Where are you from ola???and whereabouts are you??

[richyrich]

Methinks battery knackered-you say it's dry! charging system maybe SMART system, has detected low battery voltage and increased charge current from alternator to above it's normal rate and hey presto burnt fuse holder. How old is battery? Lifespan can vary. 5 years is ok. Is your car fitted with a silver calcium battery-check handbook.

[mumof4]

better off checking the battery not the handbook to see what battery he has as not everyone fits a calcium battery!

[ola]

To Mumof4:

 

To be honest, I

[mumof4]

I assume that is where you are at the moment then?

[ola]

yes, any problems?

 

/Ola

[mumof4]

None at all...just wondered where you were as i noticed the time difference.

 

Sometimes, some of us assume that the person we are helping is here in the UK.....Nothing wrong with you being elsewhere in the world.....Im just a curious person.WE welcome people from all over the place.A few of our members are elsewhere in this world.

[Bigjeeze]

None at all...just wondered where you were as i noticed the time difference.

 

Sometimes, some of us assume that the person we are helping is here in the UK.....Nothing wrong with you being elsewhere in the world.....Im just a curious person.WE welcome people from all over the place.A few of our members are elsewhere in this world.

 

 

Well if certain people are to be believed you're from another world!!! or even planet:lol:

Edited August 8, 2007 by Bigjeeze

[mumof4]

None at all...just wondered where you were as i noticed the time difference.

 

Sometimes, some of us assume that the person we are helping is here in the UK.....Nothing wrong with you being elsewhere in the world.....Im just a curious person.WE welcome people from all over the place.A few of our members are elsewhere in this world.

 

 

Well if certain people are to be believed you're from another world!!! or even planet:lol:

 

 

ssssshhhhh!!!..i was trying to keep that quiet!!..some peeps take exception to me being from Pluto!

[ola]

To Momof4

 

Ah, time difference, cunning, I thought is was my english :-)

 

Curiosity is a good thing exploring technical questions...

 

I hope I can contribute helping some of you friendly

people in this forum from the UK in the future, at the

moment I

[Bigjeeze]

Ola

 

I have a suspicion that your English is better than almost everyone on this forum's Swedish!!

 

Welcome!

[Smilge]

Welcome from me to ola ...... can you confirm that your battery is dry? ..... does it have any electrolyte (fluid) inside each of the cells? If it hasn't then do not try and charge it. If it has and the battery is a "low maintenance" type and it has gone totally "dead" then it will be useless even if it appears to charge up. Get yourself a new battery, preferably a Silver Calcium type due to the SMART charging as richyrich suggested and then when the car's running, you can check the DC voltage across the battery terminals to see if the output from the alternator is OK, as suggested by Seatkid. Good Luck.

[Andrew T]

ssssshhhhh!!!..i was trying to keep that quiet!!..some peeps take exception to me being from Pluto!

 

According to a Famous book all Women are allegedly form Venus.......

 

But back on topic. Ola, there doesn't seem any particular reason for this to happen except perhaps improper tightening of the connection bolt during installation which allows heat to build up inn the connection over the months and years slowly buring the fuse box out. Having replaced the fusebox and Alternator cable I've not had any trouble since.

The garage showed me a neat trick to see if the connection is getting hot, which is to put a droplet of water on it and see if it evaporates.

[mumof4]

You also have to make sure the connections are clean......the first time it went on me was scarey..the second time beetling along only a few months later.

 

The first time the cable was never replaced..the second time it was..and it never went again.

 

Im most def not from Venus...im not a venetian!!..im a Plutonian!!..well i must be..the amount of times ive been told im not from this planet :wacko:

[ola]

I do have a Silver Calcium battery, yes Andrew I lean towards your explanation.

I also noticed, when the engine went dead, that all electronics flickered

and fainted. After the fuse box melted, the battery must have been drained

rather quickly. The positive terminal at the battery was suspicious, I don

[mumof4]

When that fuse goes...basically all the car is driving on is whatever is left in the battery, so yes the battery would have been dead , so all the electrics would have gone doolally and died when the battery did.

[Smilge]

Ola ..... I cant see the positive connection to your battery being suspicious .... it's either connected or it isn't and if you had an intermittent connection you would have noticed it well before the fuse box melted. This sounds to me like a short circuit to the chassis straight from the battery via the fuse. One path is an internal short through the alternator so it might be worth checking this before you fit the new fusebox on monday and have the same thing happen again.

[ola]

I was thinking of replacing the fuse box without connecting the alternator.

If the alternator if faulty it shouldn

[Smilge]

I understand what you are trying to say Ola ....... What i would do with it disconnected, is to measure the resistance from where the fuse box connects to the alternator to a known chassis earth point (where the negative battery lead connects to the chassis or engine is the best way). If you have anything less than 5 Ohms then you can say you have an internal short circuit through the alternator possibly caused by one or more of the rectifier diodes going short to ground which will allow a very large DC current to run from the battery straight through to the chassis via the fuse. The alternator output will only be there when the engine is running and it initially had the rotor excitation voltage when you switched the ignition on.

 

I haven't got my TIS disc here at the mo ....... could anyone post Ola the correct wiring diagram to help with resistance measurements?

 

Cheers

 

Chris

Edited August 9, 2007 by Bleeno