Author Topic: Alternator and flat battery  (Read 1603 times)

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ciaoflyer

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Alternator and flat battery
« on: April 19, 2012, 06:51:03 PM »
My battery was flat when I left work today.  Eventually got home and put a meter on the battery, revved the engine and the meter said 13.8, so I assume the alternator is not at fault.  

I have noticed recently that when I have been driving for a while, about 15 mins all the electricals become slow, slow wipers slow indicators.

If not the alternator what could be wrong?

(I do have a spare alternator so may swap over at the weekend)
Ciao4Now

1973/126

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Re: Alternator and flat battery
« Reply #1 on: April 19, 2012, 07:23:38 PM »
 Have you checked the tension of the belt? It might be slipping under load. How old is your battery?
1972 Fiat 500
1980 Fiat 126

dajwid

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Re: Alternator and flat battery
« Reply #2 on: April 19, 2012, 07:55:47 PM »
When I had a similar problem, it turned out to be the earth strap.

Amateb8

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Re: Alternator and flat battery
« Reply #3 on: April 19, 2012, 10:26:35 PM »
It could be the battery. I had a similar situation before. The battery was simply incapable of being charged.

ciaoflyer

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Re: Alternator and flat battery
« Reply #4 on: April 20, 2012, 06:42:35 PM »
Tested again today and alternator was not charging, put the lights on and it went below 11.0 ???

So I think it's toast!
Ciao4Now

ciaoflyer

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Re: Alternator and flat battery
« Reply #5 on: April 22, 2012, 12:49:44 PM »
All sorted and it was the alternator.  It would charge one minute and stop the next!  Took it off and installed another that I had spare and away it went 14.2 all the way even under load!   :D :D

I have a very slight leak on my sump plug and the faulty ALT has had oil sprayed all over it so I think this may be where the problem has arisen, gonna strip and rebuild it!
Ciao4Now

chrisrhodesinlbz

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Re: Alternator and flat battery
« Reply #6 on: April 22, 2012, 10:37:22 PM »
Hello

I had exactly the same problem today.

My Bis has not been used much recently, so I thought I'd take it on a long run to Sussex to see my parents, and it went like a dream 100 miles down the M1, M25, M23, A22. Then coming back I stopped to fill up with petrol and starting up the car again, it just went click, RRRrrrr....rrrr and that was it.

The Green Flag man came out and connected the jump starter machine and it went, but the rate thing was only 11.9. When the ignition was switched off, it was back 'click..click'. He reckoned the alternator was not doing anything at all and it was just running off the battery.

I was faced with getting the car jump started again and hoping it would keep going for the remaining 80 miles round the M23, M25 & M1 or getting a tow truck home. I stupidly cancelled my RAC membership in the name of economy, as I had 'free' breakdown cover with Green Flag with Nat West bank account. Turned out that as I was more than 10 miles from home, I had to pay for the tow and it was £259 to get back home. Given it was 7pm on a Sunday, I got the tow.

Anyway it looks like a new altenator and maybe, for peace of mind sake, a new battery.

To me moral of the story is don't bravely go for long trips if you have only been pootling around town in your 126 for a while without checking these things, and secondly check out the terms of any 'free or complimentary' breakdown insurance. The Green Flag guys were excellent though, and the Esso garage in Copthorne was a very good place to break down.

Chris