As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE PILOT SMELLED FUEL IN THE COCKPIT SHORTLY AFTER TAKEOFF. IMMEDIATELY RETURNED TO THE BASE AND HAD MECHANIC INSPECT THE AIRCRAFT. MECHANIC DID FIND A LOOSE B-NUT THAT WAS LEAKING ON THE FUEL RETURN LINE FOR THE NR 2 ENGINE. THE MECHANIC TIGHTENED THE B-NUT, PERFORMED A GROUND RUN TO CHECK FOR LEAKS. NO FURTHER LEAKS OR ODORS WERE DETECTED AND THE AIRCRAFT WAS RETURNED TO SERVICE.