As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIR RETURN DUE TO REPORTED FLUID LEAK FROM NR 1 ENG COWLING AFTER T/O. FOUND FUEL VENTING FROM GEARBOX VENT AND EXCESSIVE FUEL IN OIL TANK. DURING INSPECTION FOUND FUEL IN OIL NR 1 ENG. REMOVED AND REPLACED FUEL/OIL COOLER. OPS AND LEAK CK NORMAL PER BOEING MM.