As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) ON GROUND RUN PILOT REPORTED R/H ENGINE RUNNING ROUGH. MAINTENANCE FOUND #2CYLINDER, EXHAUST VALVE SEAT DISLODGED, DAMAGING THE PISTON. ENGINE HAD METAL CONTAMINATION. ENGINE FIREWALL FORWARD REPLACEDWITH O/H UNIT AND COMPONENTS AND HOSES. CYLINDER ASSY HAD 596.4 HOURS SINCE REPAIR.