What was found
AFT LEVEL OFF, NR 1 MAIN CARGO SMOKE LIGHT CAME ON. SMELL OF ENG FUMES. CARGO FIRE, SMOKE FUMES AND A/C SMOKE CKLST ACCOMP. LIGHT EXTINGUISHED DURING DESCENT. REMOVED AND REPLACED WATER SEPARATOR BAGS, INSP PNEUMATIC DUCT AT AIR CLEANER FOR OIL. RAN ENG AND PACKS ALL OK. SUSP RT AIR CYCLE MACH HAS INTERNAL OIL LEAK. *S/D* REMOVED AND REPLACED RT AIR CYCLE MACHINE.