In article <01HU2NMWECEQ004J23@udavxb.oca.udayton.edu>,
MORROW@udavxb.oca.udayton.edu wrote:
> Only with a Lucas system could a dead alternator cause the very
> light that is supposed to tell you that the alternator is dead to cease its
> function altogether.
Not so - all alternators of various brands that I have come across work
in the same manner:
One side of the lamp is connected to the ignition circuit, the other to
the alternator field. What happens is:
* When the alternator is not rotating, there will be no charge
and hence no voltage to the field coil. The light will be lit
due to the current going through the field coil towards ground.
BTW: this tiny current is very important since it generates
the small magnetism required for the alternator to start
charging in the first place.
* When the alternator is charging, the field coil will get its
supply from the charging circuit, and the voltage will be about
14V on both sides of the ignition lamp - hence no light.
* If there is an interruption in the field coil, brushes or the
ignition lamp itself, there will be no charge as well as no
light in the ignition lamp. The only way of being sure of a
proper charge is to check the voltage at the battery - it should
be approx. 14V when the engine is running above tickover and
the battery is charged to a reasonable degree. A reading below
13V is a definitive no-no.
BTW: My impression is that people seem to throw away their electric gadgets
prematurely.
The primary reasons for an alternator to fail is:
1. Worn out brushes. The brushes are not particularily long
lasting on the Lucas alternator, but they are extremely simple
to check and replace.
2. Blown diodes. Requires soldering skills to check and replace.
Similarily, the starter usually fails due to:
1. Worn out bushes. Requires soldering skills to check and
replace.
2. Worn out bearings. Fairly simple to replace.
The procedures are all in the book. A simple universal meter is required
for checking diodes, resistance and voltages. The cheap $10-15 instruments
available at electronic stores are perfectly OK - if only one stores them
in a dry and safe place, not together will the spanners and hammers in
the tool box.
Egil
--
Email: egilk@oslonett.no Voice: +47 22523641/92022780 Fax: +47 22525899
Snail: Egil Kvaleberg, Husebybakken 14A, 0379 Oslo, Norway
URL: http://www.oslonett.no/home/egilk/
URL: http://www.oslonett.no/home/egilk/t2000.html
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