What was found
MSY - AFTER TAKEOFF WHEN LANDING GEAR WAS RETRACTED, NOSE LANDING GEAR DID NOT RETRACT. FOLOWED ORH PROCEDURES. FOUND NOSE LANDING GEAR STRUT DEFLATED AND A DEFECTIVE SCHRADER VALVE. SERVICED NOSE LANDING GEAR STRUT WITH HYDRAULIC FLUID AND REPLACED SCHRADER VALVE, MFG P/N B050762, AND DRY NITROGEN. NOSE LANDING GEAR OPERATION THEN CHECKED NORMAL.