What was found
THE NOSE GEAR WOULD NOT RETRACT AFTER TAKEOFF. WHEN CYCLING THE GEAR, THE GEAR CAME DOWN, BUT THE GEAR HANDLE WOULD NOT RAISE. BOTH THE STALL INDICATION FAIL LIGHT AND AUTO SPOILER DO NOT USE LIGHT ILLUMINATED. THE AIRCRAFT WAS RETURNED TO SFO WHERE IT LANDED WITHOUT INCIDENT. MAINTENANCE FOUND METERING PIN BASE LOOSE IN LOWER CYLINDER; UPON REMOVAL PRESSED IN SLEEVE CAME OUT WITH BASE. THE LOWER PISTON AND AXLE ASSEMBLY WERE REPLACED IAW MM 32-21-02. THE NLG RETRACT CYLINDER AND BUNGEE CYLINDER WERE BOTH REPLACED AS A PRECAUTIONARY MEASURE. THE NOSE GEAR WAS SWUNG AND OPERATION CHECKED GOOD.