What was found
(CAN) NR 1 STRUT OVERHEAT LIGHT WARNING CAME ON WHILE CLIMBING THROUGH 8,000 FEET ON TAKEOFF. POWER WAS REDUCED, LIGHT EXTINGUISHED AND AIRCRAFT RETURNED TO ITS POINT OF DEPARTURE. POST-FLIGHT INSPECTION FOUND THE 8TH STAGE CHECK VALVE, ON NR 1 ENGINE LEANING AT THE CLAMPS AND THROUGH THE VALVE PIN HOUSING. THE 8TH STAGE CHECK VALVE WAS REPLACED AND IT CHECKED SERVICEABLE.