Can Air conditioner pully just come loose without it being the whole ac compres

Could just be a clutch assy or bushing issue. There are many possibilities what could be effecting this condition and way too many to be guessing on. If you want to get this problem diagnosed professionally, please call us , (313) 208-7752 or schedule your appointment on line at StansGarage.net. I am sure we can diagnose your problem and give you the answer you need. Larry