voltmeter reading (was: cheap 90 amp alternator fix)

[ti@amb.org (Ti Kan)]

Speaking of alternators, I have a question.

My 4000 (which has a 90A alt) voltmeter would show about 13V when the
car is started first time in the morning, and after warming up the reading
would drop to about 12V or so.  I know that the voltmeter is reading a bit
low due to the ground arrangement as well as the voltage drop across
the various wiring and connectors, but why would the reading drop over time?

In comparison, my A4's voltmeter would read a bit over 14V pretty
much all the time...

-Ti
96 A4 2.8 quattro
84 5000S 2.1 turbo
80 4000 2.0
-- 
    ///  Ti Kan                Vorsprung durch Technik
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