As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) EXCESSIVE WEAR OF EXHAUST SEAT WAS NOTED IN 109 HRS OF TOTAL OPERATION. THE VALVE WAS ADJUSTED TWICE IN THE SPAN OF OPERATION BEFORE THE CYLINDER ASSY WAS REMOVED FROM SERVICE. EXHAUST VALVE SEAT WEAR IS APPROXIMATELY .175. ALL REMAINING CYLINDERS ON THIS ENGINE ARE FUNCTIONING NORMAL FOR THE TYPE. NUMEROUS INCIDENTS OF THIS NATURE HAVE RECENTLY OCCURED. THE ENGINE HAS BEEN OPERATED ON MOGAS.