As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RFD CONTROL TOWER NOTED SPARKS COMING FROM COWLING AREA. UPON COWL REMOVAL NOTED ALTERNATOR AND ALTERNATOR PULLEY HAD BEEN LOOSE AND WOBBLING. ALTERNATOR HOUSING GOUGED, PULLEY SEVERELY DAMAGED FROM EXCESSIVE WOBBLING AND VIBRATION. ROTOR SHAFT END AND THREADS GOUGED AND SEVERELY WORN. ALTERNATOR FORD PN DOFF 10300B.TRANSIENT AIRCRAFT, MAINTENANCE HISTORY UNKNOWN.