As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) OIL PRESSURE LOSS/IFSD DURING CLIMB THROUGH FL210, THE CREW OBSERVED A LOW OIL PRESSURE INDICATION ON THE LT ENGINE. THE CREW SHUT THE ENGINE DOWN AND RETURNED TO THE DEPARTURE POINT WHERE AN UNEVENTFUL SINGLE ENGINE LANDING WAS PERFORMED. MAINTENANCE FOUND THE GARLOCK SEAL OF THE STARTER GENERATOR DRIVE GEAR HAD COME OUT OF ITS CARRIER CAUSING A MAJOR OIL LEAK. A NEW SEAL WAS INSTALLED AND THE ACFT WAS RETURNED INTO SERVICE.