Walbro LMK Carburetor Idle Needle Adjustment

[oli]

I am working on a Walbro LMK Carburetor. The carburetor is on a John Deere, LT 155 lawn tractor with 15 hp Kohler Command Engine, model CV15S, C-series. This carburetor has an idle needle adjustment. When I cleaned the carb, i removed the idle needle. The idle needle was roughly 1 full turn out from fully seated and replaced in the same position. After I re-installed the carb, and started the the engine, i tried to fine tune the idle needle between the high and low mid-point idle speed. There was no change in the idle speed regardless of how I turned the the idle speed needle jet screw. What is the process for adjusting the idle needle on this carburetor. Thanks in advance, Oli

[SUKI]

Air cleaner and filter must be in place but is the JD instructions from their service manual. You can sub the photo tach to the inductive type.