What was found
SHIP 6700 RIEF ACRID FUME IN COCKPIT ON DEPT AT FL220 AFTER TURNING ON ENGINE ANTI ICE. PACK AT ROWS 20-22 REPORTED SAME. ON DESCENT FUME RETURNED AND PERSISTED THROUGH LANDING ASSOCIATED WITH ENGINE ANTI ICE. CORRECTIVE ACTION: T/S REMOVED AND REPLACED LT WING LEADING EDGE HYDRAULIC SLAT PDU MOTOR, CK GOOD NO LEAKS. INSTALLED NEW WING LEADING EDGE SUPPLY DUCT AND NEW SHROUD PER B757 AMM 36-11. (6627350)