As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PILOT EXPERIENCED RISE IN ENGINE OIL TEMPERATURE DURING STRAIGHT AND LEVEL FLIGHT. PILOT COULD NOT RECTIFY THROUGH INITIAL EMERGENCY PROCEDURES AND INITIATED A LAND AS SOON AS POSSIBLE AND CONDUCTED PEL. OIL TEMP REACHED 116 DEG, FAULT TROUBLESHOT IAW PWC PT6B-37A 72.00.00 FIGURE 159, THERMOSTATIC BYPASS SUSPECTED AT FAULT DUE TO PREVIOUS FAILURES TO INCLUDE SIMILAR EVEN ON SDRS CONTROL # 202FA0000340. REPLACED PART THERMOSTATIC BYPASS VALVE, OPS CHECKS POST MAINTENANCE SAT.