As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(AUS) NO3 CYLINDER EXHAUST VALVE SPRING LOCKING KEYS SHATTERED BUT WERE STILL HOLDING THE SPRINGS IN PLACE. CAP PNO MS13998-3 ALSO HADSEVERAL CHIPS MISSING. THE VALVE SEAT WAS DAMAGED BEYOND LIMITS.FOUND DURING INSPECTION IAW LYCOMING SB 388B. NO EVIDENCE OFMETAL IN THE OIL FILTERS.