As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER REMOVAL OF THE CYLINDER BARREL FROM THE CYLINDER HEAD, SEVER ERROSION WAS NOTED JUST ABOVE THE SEAL BAND AREA. IF THE BARREL HAD NOT BEEN REMOVED, THIS ERROSION WOULD HAVE BEEN UNDETECTED AND WOULD HAVE CAUSED A HEAD AND BARREL SEPERATION.