As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) EXHAUST VALVE BROKE AT SEAT CONTACT AREA CAUSING PISTON DAMAGE AND ENGINE STOPPAGE. REMAINDER OF VALVE TRAIN PARTS SHOWED MORE WEAR THAN NORMAL INDICATING HAMMERING OF VALVE TRAIN COMPONENTS. THIS CONDITION IS RELATED TO IMPROPER PURGING OF THE OIL SYSTEM AT ENGINE INSTALLATION.