As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT ARRIVED WITH A ROUGH ENGINE. OPERATIONAL CHECK OF ENGINE REVEALED DANAGE IN NR 2 CYLINDER. FOUND THAT EXHAUST VALVE HAD BROKEN AND DESTROYED PISTON ALSO. ENGINE HAD 1122.7 TIME SINCE OVERHAUL. PREVIOUS COMPRESSION CHECK SHOULD HAVE REVEALED ANY PROBLEMS WITH VALVE. ENGINE LOG DID NOT REVEAL ANY COMPRESSION CHECKS. ENGINE OVERHAULED AND RETURNED TO SERVICE.