Alternators burning out

[lout]

so fans were drawing 20amps?
and battery was charging 20amps?

 

[chrisp]

Measured the voltage output on the back of the alternator? Measure the voltage drop between the battery and the alternator?

^^^^^ this!

We really need the voltage readings at the battery (and alternator) ant idle, and revved up a bit, to have any idea what the charging system is doing.