As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AT 100 HR INSP NOTICED LEFT MAG TIMEING INCORRECT. AFTER DISSASEMBLY FOUND PT.S COATED AND IMPULSE COUPLING PAST 500 HR LIMITS, VARIOUS OTHER PARTS WERE WORN WORSE THAN THE ENG REBUILDER'S CLAIMED TIME IN SERVICE OF MAG WOULD DICTATE (350 HR.S SINCE NEW). BOTH MAGS WERE REPLACED AS A PRECAUTION. STRESS THE IMPORTANCE OF A 500 HR MAG INSPECTION.