What's hangin' outa the front of my A/C compressor?

[Steve Scalmanini]

My A/C quit yesterday.  The frontmost disc on the compressor is hanging 
loose off the front of the unit (gently against the aux. radiator.)  The 
reason it hasn't fallen off completely is that it's still connected to 
the shaft it bolts to, and the shaft continues inside the pulley for a 
ways, although loosly.  The pulley still turns normally and doesn't make 
any odd noise.  

Does anyone know what happened?  Did the main shaft inside the compressor 
snap, or has something come apart that is reassemblable or repairable, 
like the A/C clutch assembly?  

I don't see anything in Bentley that shows that the shaft should be 
anywhere except inside the compressor, although the clutch disc seems 
to bolt onto the shaft end with a few shims behind it.  (See p. 87.34 
in volume 2.) 

TIA, 

Steve 
Ukiah, CA 
91 200Q20V  195K