What was found
PILOT REPORT LOSS OF POWER & TORQUE FLUCTUATION IN CLIMB, LASTING FOR APPROX 5 SECONDS, THEN POWER SMOOTHED OUT. PILOT ELECTED TO RETURN TO DEPARTURE AIRPORT WITHOUT INCIDENT & REPORTED THE PROBLEM. INSPECTED ENG & ACFT FUEL SCREENS, FILTERS & SUMPED ALL FUEL DRAINS. FOUND NO INDICATIONS OF CONTAMINANTS OR WATER. A GND PERFORMANCE RUN WAS PERFORMED FOR 5 MINUTES WITH ALL NORMAL INDICATIONS. ACFT WAS RELEASED FOR OPERATIONAL CHECK FLIGHT, THIS FLIGHT WAS PERFORMED FOR 30 MINUTES AT VARIOUS POWER SETTINGS. ENG PERFORMANCE WAS GOOD & ALL INDICATIONS WERE STEADY & WITHIN LIMITS. THE VAGUE DESCRIPTION OF THE SUSPECTED FAULT & LACK OF FINDINGS DURING INSPECTION WILL NOT ALLOW FOR A CONCLUSIVE IDENTIFICATION OF