What was found
AFTER TAKEOFF ON FLIGHT #3142, AT APPROXIMATELY 400' DURING THE AFTER TAKEOFF FLOW THE LH ENGINE TORQUE WENT TO 20%, AND A MASTER WARNING LIGHT ILLUMINATED. ALMOST SIMULTANIOUSLY THE LH ENGINE OVERTEMP LIGHT WENT ON TEMP WAS AT 1000-1007 DEGREES C. CLEAR, NO ICE. AIR RETURN TO PIR. MAINTENANCE REMOVED AND REPLACED LEFT ENGINE AND PGB ASSEMBLY PN CT7-9B SN/OFF GE-E-785692, SN/ON GE-E-785370 PER JC 7100-301. LH AND WORK PACKAGE FROM PLANNING ISSUED 12/6/02. REFERENCE WO # 337791. ALL LEAK AND OPS CHECKS GOOD.