To check the integrity of your
alternator pulley, simply remove the belt and place a screwdriver into
the front of the alternator cooling fan to stop the armature from
rotating. Then turn the pulley by hand. If it moves one direction but,
not the other, it is functional. If it will not rotate at all, it has
failed.
IMPORTANT: Do not attempt to retrofit a 180 Amp unit to a 220 Amp or to a 250 Amp, vice versa.
