What was found
YVR FLIGHT NR 2029, AFTER TAKEOFF DURING FLAP RETRACTION GOT NR 1 ENGINE HYD PUMP CAUTION LIGHT. PRESSURE INDICATED 2000 PSI ON BOTH STANDBY AND MAIN NR 1 HYDRAULIC PRESSURE GAUGES. WHEN FLAPS WERE UP ALL INDICATIONS WENT BACK TO NORMAL. NO OTHER CAUTION LIGHTS NOTED. PERFORMED EA CHECKLIST. MAINTENANCE INSPECTED NR 1 HYDRAULIC SYSTEM FOR LEAKS. NO LEAKS NOTED. NO DEFECTS NOTED. NO PARTS REPLACED. AIRCRAFT RETURNED TO SERVICE.