In article ,
Onetap wrote:
On Friday, October 26, 2012 10:10:19 AM UTC+1, Dave Plowman (News) wrote:

Quite. But then jump starting didn't cause the alternator to fail - it

would also have failed if the engine was started by any other method with

this faulty battery still in circuit.

Defective (or disconnected) battery + jump start = dead alternator.
Which is what I have said repeatedly to a chorus of derision.

No - you said with a 'flat' battery. A very different matter from an open
circuit one. The first is likely why someone would jump start a car - the
second a fairly unusual occurrence.

I didn't know that could happen and it cost me an alternator to learn.

An breakdown service would have jump started it too with the same result.

You usually don't have a battery charger or a multi-meter to hand when
you need to jump start a car.

It would probably be safest to run the engine until the flat (?)
battery had enough charge, then turn both off and disconnect the jump
leads.

If the battery was totally open circuit it will never take a charge. Or
rather if it will, needs a very long slow charge at high voltage - days.

--
*Ambition is a poor excuse for not having enough sense to be lazy *

Dave Plowman London SW
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