What was found
DURING A SIMULATED ENGINE FAILURE FOR A CFIA LESSON, THE ENGINE EXPERIENCED ROUGHNESS AND PARTIAL POWER LOSS DURING THE PLANNED GO-AROUND AT 800 FEET. AN EMERGENCY WAS DECLARED AND THE AIRCRAFT LANDED WITHOUT FURTHER INCIDENT. POST FLIGHT INSPECTION REVEALED THAT THE #1 CYLINDER EXHAUST PUSHROD WAS BENT DUE TO A STUCK EXHAUST VALVE. ALL EXHAUST VALVES WERE INSPECTED IN ACCORDANCE WITH LYCOMING SB 388C AND LYCOMING SI 1485A. CYLINDERS 1, 3, AND 4 VALVE GUIDES REQUIRED HONING TO ACHIEVE SPECIFIED LIMITS. THE DAMAGED PUSHROD AND PUSHROD TUBE WAS REPLACED. NO FURTHER DAMAGE WAS FOUND. THE ENGINE WAS OVERHAULED 713 HOURS PRIOR TO THE FAILURE AND THE OVERHAULER USED PMA MILLENNIUM CYLINDER ASSEMBLIES FROM SUPERIOR AIR PARTS.