What was found
NRT: AFTER T/O SMOKE OF UNKNOWN ORIGIN APPEARED IN COCKPIT; DID AIR TURNBACK AND RETURNED TO NRT. SMOKE APPEARED TO BE COMING FROM AIR CONDITIONING. FOUND DIRTY OIL IN COALESER OF WATER SEPARATOR IN THE NR 1 PACK AND WET OIL IN NR 1 ENG STATER PNEU DUCT IN THE NR 1 ENG. ALSO, FOUND HOLE BY CHAFING BY HYD LINE (MAINTENANCE REV HALF OPEN MECH) ON THE NR 1 ENG BLEED DUCT. THEN CLEANUP INSIDE OF NR 1 PACK WATER SEPARATOR AND R/R COALESER ALSO BLEED DUCT.