The serpentine belt keeps falling off

YOUR TENSIONER MAY BE WORN--NO LONGER TENSIONS RIGHT

MAYBE A PULLEY IS NOT IN LINE (FLOPPY--INSTALLED WRONG)

DO ALL OF THE PULLEYS TURN FREELY W/ THE BELT OFF. EXCEPTION: CRANKSHAFT PULLEY

IF YOU HAVE A PULLEY THAT BOLTS ON----ARE THE BOLTS TIGHT?

DOES THE CLUTCH (INNER MOST PART OF THE A/C PULLEY) TURN FREELY W/ ENGINE OFF----ENGINE OFF---ENGINE OFF. USING YOUR FINGERS?

. WHEN THE A/C OR DEFROST IS TURNED ON----THE CLUTCH ENGAGES THE A/C COMPRESSOR---BOTH SETTINGS USE THE COMPRESSOR

THE A/C CLUTCH PULLEY MAY TURN JUST FINE WITH IT FREEWHEELING. BUT WHEN YOU TURN ON THE A/C OR DEFROSTIF THE COMPRESSOR IS "LOCKED UP" (BAD)----SUDDENLY THE PULLEY WON'T TURNCAUSE IT'S NOW COUPLED TO THE PART UNABLE TO TURN. THIS MAY SLING A BELT TOO!

THE MEDIC