As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
NR 3 CYLINDER INTAKE ROCKER CAME LOOSE FROM BACKED OFF NUT AND BROKEN STUD. ROCKER BOUNCED AROUND INSIDE OF ROCKER COVER AND POKED HOLE IN COVER. METAL FROM COVER CONTAMINATED ENGINE. INSPECTED OIL FILTER AND FOUND FERROUS METAL INSIDE OF FILTER. ENGINE, PROP AND PROP GOVERNOR HAS TO BE TORNDOWN AND FLUSHED FOR METAL CONTAMINATION. REPAIRED CYLINDER WAS INSTALLED ABOUT 12 HOURS PRIOR TO INCIDENT. OWNER ADVISED OF THE SITUATION.