my a/c compressor went bad and i got another compressor from a guy i know....my question is....is the whole end of the compressor supposed to spin freely...or should it be locked up. by the way the compressor is off the car.

 

the outer ring on the compressor clutch(the part the belt attaches to) should spin freely and without any jingly noises.

The clutch center part should spin as well but you will have to move it by hand slowly. also, you will/should hear suction at the two line holes. possibly even some oil and stuff squirting out of it if there's any left in.

put your fingers completely over both holes and turn the clutch by hand, should should feel a good bit of suction on your fingers.

If any of the above dont happen. pass it by. it be bad.