Mercury - Quicksilver Inlet Needle OEM Precision Fuel System Part 803861. Overview. A small part can make a big difference in how your outboard runs. The Mercury Marine 803861 Quicksilver Inlet Needle keeps your carbureted Mercury or Mariner 10-25HP 2-stroke outboard running smooth and consistent by controlling fuel flow with exact precision. When the old needle starts to wear out, you'll feel it - rough idle, flooding, or a motor that just doesn't want to start right. Replacing it with this gen