What was found
NOSE LANDING GEAR DID NOT SHOW DOWN AND LOCKED. GEAR LAMP WOULD INTERMITTENTLY LIGHT AND HYDRAULIC PRESSURE LIT WOULD INTERMITTNETLY ILLUMINATE. DISASSEMBLY AND T/S SHOWED SHUTTLE VALVE STUCK. CLEANED, REASSEMBLED AND TESTED. N2 BOTTLE REMOVE, CLEANED, INSPECTED AND REFILLED, LEAK CHECKED, REINSTALLED. MONITOR FOR PRESSURE DROP, NONE NOTED. ACTIVATED EMERGENCY NITROGEN BLOW-DOWN BOTTLE. GEAR DOWN AND LOCKED WITH BOTTLE PRESSURE. SUSPECT POSSIBLE N2 BOTTLE LEAK, DIRTY SHULLTE VALVE, HOWER, PREFLIGHT INSPECTION OF PRESSURE BOTTLE WAS WITHIN LIMITS. (K)