What was found
YELLOW HYD RESV OVHTINFLIGHT. EMERGENCY RETURNED TO KDEN. OPERATED BOTH FWD AND AFT CARGO DOORS SEVERAL TIMES AND THE DOOR ENTERED ROTABLE PART INFO. SELECTOR SWITCHES RETURNED TO THE NEUTRAL POSITION EACH TIME ROTABLE PARTS CHANGE WAS INDICATED - TT # 1958381 SN OFF 4249 WITH A SOLID CENTERING ACTION. THE YELLOW PUMP TURNED OFF AFTER THE DELAY PERIOD EACH TIME. PUMP, AC MOTOR OFF 31-2914-9-0001 4249 ON 31-2914-9-0001 3116 ACCOMPLISHED TSM 29-13-00-810-802-A, FOUND CHECK VALVE (3083GM) DEFECTIVE. REMOVED AND REPLACED CHECK VALVE IAW AMM 29-24-21 AND YELLOW ELECTRIC PUMP (3075GX) IAW AMM 29-24-51. OPS CHECK AND LEAK CHECK GOOD FOR BOTH COMPONENTS AT THIS TIME. ADD