What was found
DFW - FLT 1958 - AFTER TAKEOFF FROM DFW, THE NOSE LANDING GEAR WOULD NOT RETRACT. LOWERED LANDING GEAR HANDLE AND RECEIVED THREE GREEN DOWN AND LOCKED LIGHTS. RETURNED TO DFW AND LANDED WITHOUT INCIDENT. REPLACED NOSE GEAR CONTROL VALVE. ACCOMPLISHED GEAR SWING, SYSTEM GROUND CHECKED NORMAL OPERATION. (M)