As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE VALVE STEM UNDER THE KEEPER'S WAS HEAVILY WORN. THIS CONDITION WAS ALSO FOUND ON 4 OTHER VALVES (INTAKE) ALL HAVING THE SAME TOTAL TIME AND PART NUMBER. THE 6TH VALVE WAS A LYCOMING WITH THE SAME TIME AND INSTALLATION DATE. NO PROBLEM FOUND.