As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
VALVE FLAPPERS DEVELOP CRACKS. FLAPPER TO BODY HINGE HAS PREMATURE WEAR CAUSING HINGE TO SEPARATE FROM BODY. SUBMITTER STATED COMPONENT CONSTRUCTION IS ALUMINUM ALLOY. TIME CONTROL OF COMPONENT MAY ELIMINATE EXCESSIVE WEAR CONDITIONS ELIMINATING OPERATOR DIFFICULTY REPORTS AND DISCREPANCIES.