What was found
SMOKE APPEARED IN THE CABIN AND COCKPIT WHILE EN ROUTE FROM HKG TO EWR. THE CREW DONNED OXYGEN MASKS AND COMPLETED THE APPROPRIATE CHECKLIST. THE SMOKE QUICKLY DISSIPATED. THE ACM L AND FCV L EICAS MESSAGES WERE ALSO OBSERVED. THE AIRCRAFT WAS DIVERTED TO NRT WHERE IT LANDED WITHOUT INCIDENT. MAINTENANCE FOUND THE LT ACM SEIZED WITH A BLADE MISSING AND THE DIFFUSER HOUSING WAS DETERIORATED. THE LT ACM AND DIFFUSER HOUSING WERE REMOVED AND REPLACED IAW MM 21-52-02 AND 21-52-06. LEAK AND OPERATIONAL CHECKS WERE GOOD. THE UPPER FLOW CONTROL VALVE (PACK AIR SUPPLY VALVE) WAS ALSO REMOVED AND REPLACED IAW MM 21-51-01.