As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ENGINE S/N RL-35534-51E WAS FOUND WITH A STICKING EXHAUST VALVE AT 434.1 HOURS TOTAL TIME. THE CYLINDER WAS REPLACED. THIS ENGINE INCORPORATES NI-RESIST VALVE GUIDES AND THE TIME TO FAILURE IS CONSIDERED BY THIS AGENCY TO BE PREMATURE.