What was found
SMOKE DETECTOR IN RIGHT AFT LAV WENT OFF ON TAKEOFF ACCOMPANIED BY A SMELL OF SMOKE, AIR RETURN TO FLL. REMOVED AND REPLACED RIGHT ACM AND BURN OUT OF PNEUMATIC DUCTS. REMOVED AND REPLACED BOTH, REMOVED AND REPLACED BOTH COALESCER BAGS AND LEAK CHECKED. HI POWER RUN, NO SMOKE OR SMELL IN CABIN, OPS CHECK OF SMOKE DETECTOR OK. (M)