As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
BIL - PDX, DIVERTED TO LWS AT FL 240 CRUISE, NR 1 ENGINE OIL PRESSURE BEGAN TO FLUCTUATE AND OIL PRESSURE DROPPED BELOW ALLOWABLE LIMITS AND ENGINE WAS SHUTDOWN. MAINTENANCE DOWNLOADED EMU AND SENT FILE TO TECH SERVICES FOR ANALYSIS. INSPECTED NR 1 ENGINE AND FOUND MAJOR OIL LEAK FROM OVER SPEED GOVERNOR CAUSING OIL PRESSURE LOSS. REMOVED AND REPLACED OVER SPEED GOVERNOR. SERVICED ENGINE WITH OIL. NO DEFECTS NOTED. AIRCRAFT RETURNED TO SERVICE.