As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ACFT RETURNED TO DEPARTURE DUE TO THE NR2 ENGINE GENERATOR FAILURE AND LOSS OF OIL PRESSURE. CREW HAD TO SHUTDOWN AND FEATHER THE NR2 ENGINE. THE ACFT LANDED SAFELY AND WAS TOWED BACK TO THE GATE. MX DISCOVERED THAT THE NR2 ENGINE AC GENERATOR V-BAND CLAMP WAS BROKEN AND THE AC GENERATOR HAD FALLEN FROM THE MOUNTING PLATE. THE AC GENERATOR IS COOLED BY ENGINE OIL WHEN THE AC GENERATOR DETACHED FROM THE HSG THE OIL WAS PUMPED OUT OF THE ENGINE RESULTING IN THE CREW COMMANDED ENGINE SHUTDOWN.