If it is the style with 4 bolts, I use two wrenches.  I hold the thing
from spinning with the wrench on one bolt and turning the other wrench.
 I alternate until I get to the last one, then I use one that has
already been broken free to hold for the last tight one.  That one that
was already broken free will normally untighten again with little effort
or by holding the pulley.

Sometimes I can back out the loose bolts enough to use a screwdriver
across two as a lever to hold it for the last tight one.

I also never undo the fan belt unless I am planning on replacing it or
it needs adjusting.  The belt will come loose with the fan pulley and
tighten up exactly the same as before when the pulley goes back on.

Same for the alternator or PS pump bracket.  Usually the pumps will
twist out from under them without having to undo everything.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
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