Load adjusting needle, complete assembly, for Zenith carbs on JD 3010-4020 series tractors. It is the back mounted version. Back mounted means it is located on the back side (opposite of the air intake) of the carburetor as shown on the parts breakdown. This assembly will take the place of the, JD #AT25578, or Zenith A75-12 electronic solenoid that was offered on these carbs. The complete electronic solenoid would be unscrewed from the carburetor and this complete manual load needle assembly would be screwed back in it's place. JD-48 gasket is sold separately under Key 42. Threads are 1/2-20.
