if the fuse is blowing then there is a short in the air conditioning circuit that is allowing too much current to flow through the circuit. THe clutch for the compressor is an electro-magnetic clutch. The clutch turns freely because you are working the mechanical portion of the clutch. In all probablility when you go to engage the clutch electrically the fuse blows. You can't turn the compressor without engaging the compressor clutch, so I can't tell you if the compressor is seized causing the clutch to burn out or if the clutch just burnt by itself. You'll have to have the compressor removed and the clutch removed to tell if teh compressor is seized or not.if it is a compressor and clutch assembly you'll be looking at about $1000 to replace it. If its just the clutch it would be about $400 parts and labor.hope that helps