What was found
JFK INFLIGHT T837/30 OCT - AFTER TAKEOFF THE AFT LAVATORY FIRE SMOKE ALARM WENT OFF. FLIGHT ATTENDANT REPORTED SOMETHING BURNING IN AFT LAVATORY. ALSO REPORTED A GRINDING MOTOR SOUND WHEN THE SMOKE DISSIPATED. RETURNED TO JFK AND LANDED WITHOUT INCIDENT. REPLACED NUMBER 7 AFT GALLEY OVEN AS PRECAUTION. REPLACED RIGHT ENGINE DUE TO OIL IN HIGH PRESSURE COMPRESSOR AND ACCOMPLISHED PACK BURN AND OVERWEIGHT INSPECTION. SYSTEM GROUND CHECKED NORMAL OPERATION.