What was found
CREW REPORTED THAT AFTER APPROXIMATELY 15 MINUTES INTO FLIGHT THEY NOTICED A BURNING OIL SMELL COMING FROM THE OVERHEAD VENTS. ACTIONS WERE TAKEN TO ISOLATE THE SMELL BY TURNING OFF FANS AND ISOLATING BLEED AIR SOURCES. A/C DIVERTED TO KCRG WHERE A NORMAL DESCENT AND LANDING WERE ACCOMPLISHED. MAINTENANCE RAN THE AIRCRAFT AND CONFIRMED THE PROBLEM. IT WAS DISCOVERED THAT OIL WAS DRIPPING ONTO A HOT BLEED DUCT IN THE AFT EQUIPMENT BAY. A B-NUT WAS TIGHTENED THAT RAN FROM A FILTER TO THE FLOW SWITCH. AIRCRAFT WAS RAN FOR 30 MINUTES WITH NO EVIDENCE OF THE OIL SMELL. B-NUT WAS RECHECKED AND NO LEAKS WERE NOTED. AIRCRAFT WAS RETURNED TO SERVICE.