As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) DURING MAINTENANCE TO FIND SOURCE OF OIL LEAK ON ENGINE IT WAS FOUND THAT THE REAR ENGINE CASE WAS CRACKED. THE REAR ENGINE CASE WAS CRACKED AT LEFT MAGNETO PAD WHICH HAS ENGINE OIL RUNNING UNDER IT, THIS CAUSED THE OIL LEAK. ENGINE WAS REMOVED AND REAR CASE AND BLOWER ASSY CHANGED WITH OVERHAULED UNIT. ENGINE WAS REINSTALLED GROUND RUN & RETURNED TO SERVICE