What was found
IDLER IN NOSE GEAR RETRACT LINKAGE BROKE DURING RETRACTION DUE TO INTERFERENCE OF NOSE GEAR AND WHEELWELL DOORS. NOSE GEAR FAILED TO EXTEND DUE TO LOSS OF NITROGEN CHARGE IN STRUT. STRUT HAD BEEN OVERSERVICED WITH HYDRAULIC FLUID. WITH THE STRUT BEING OVERSERVICED WITH FLUID, THE EXTENSION APPEARED NORMAL ON THE GROUND. PROPER SERVICING OF OLEO STRUT WOULD HAVE CAUSED A COLLAPSED STRUT WHEN THE NITROGEN CHARGE WAS LOST AND A COMPLETE PRE-FLIGHT INSPECTION WOULD HAVE NOTED THIS DISCREPANCY.