As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE AIRCRAFT ENGINE HAD FREQUENT PROBLEMS WITH THE ALTERNATOR BELT COMING OFF. MAINTENANCE INSPECT THE COUNTERWEIGHT ATTACH BUSHING FOR DEFECTS. ON INSPECTION IAW SERVICE BULLETIN MSB 99-3C, IT WAS DETERMINED THAT WEAR TO BUSHING WAS FOUND TO BE .004" FROM ORIGINAL. THE CORRESPONDING PIN WAS ALSO FOUND TO HAVE WEAR OF .004". REPLACED ENGINE.