What was found
THE STUD THAT HOLDS DOWN THE EXHAUST ROCKER SNAPPED OFF, CAUSING ROCKER AND RELATED PARTS TO FLOAT AROUND IN VALVE COVER. LOOSE PARTS THEN LODGED BETWEEN INTAKE ROCKER CAUSING 30 DEGREE BEND IN PUSH ROD AND SHROUD. THE STUD THAT BROKE, BROKE AT THREADS WITHIN THE CYLINDER HEAD. PARTIAL POWER LOSS IN FLIGHT, PILOT MADE AN EMERGENCY LANDING AT 4S2.