As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
UPON COMPLETING THE FIRST 500 HOUR INSPECTION ON THE MAGNETO, IT WAS DISCOVERED THAT THE CARBON BRUSH AND SPRING ASSY (PN 10160844) WERE NOT INSTALLED. THE BUSHING IN THE DISTRIBUTOR GEAR HAD BEEN MAKING CONTACT WITH THE TAB ON THE COIL SO THE MAGNETO APPEARED TO BE FUNCTIONING NORMALLY. ADDITIONALLY, THE WEDGES (PN 10349219) THAT SECURE THE COIL ASSEMBLY INTO THE CASE WERE OVER-DRIVEN, BENT AND MALFORMED SEVERELY BY THE INSTALLATION PROCESS WHEN MANUFACTURED.