What was found
YVR - UPON ADVANCING POWER LEVERS FOR TAKEOFF, NR 2 ENGINE EXPERIENCED A UNSCHEDULED FEATHERING OF THE PROPELLER. ABORTED TAKEOFF AND RETURNED TO THE GATE. AIRCRAFT WAS FERRIED FROM YVR-PDX FOR REPAIRS. FDR WAS DOWNLOADED AND NR 2 TORQUE CONFIRMED TO BE 150 PERCENT. ADJUSTED ARM OF SWITCH 6141S4, REPLACED BOTH PROP CONTROL UNITS, RIGGED DOWNLOAD SWITCHES 6141S3 AND 6141S4. ALL OPERATIONAL CHECKS GOOD. AIRCRAFT RETURNED TO SERVICE.