As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) THE RT ENG WOULD NOT START, SO IT WAS SENT TO MX WHERE THEY DISCOVERED ON THE NR 4 CYLINDER, THE EXHAUST VLVS WERE STUCK OPEN & THE PISTON WAS SCORED. THE CYLINDER HEAD WAS REMOVED AS WELL AS THE PISTON. DISCOVERED THAT THE RINGS HAD LOST THEIR TEMPER, BUT THE PISTON & HEAD WERE OK. THIS IS AN ENG THAT WAS REPLACED DUE TO FAILURE IN AUGUST 2014 & HAD ONLY 197 HOURS ON IT. THE ACFT HAS 933.6 HOURS ON THE AIRFRAME.