1995 Johnson/Evinrude Outboards 9.9, 15 four-stroke Service Manual, Page 64Get this manual
Carburetor Mixture Adjustment 1Start the engine and run it in FORWARD at one-half throttleAllow the engine to reach normal operating temperature[] 2Tiller modelsAs you face the steering handle, turn the idle speed adjustment knob counterclockwise to full SLOW speed position
3Use OMC Idle Adjustment Tool, PIN 910245, to adjust idle mixture
4Run the engine at slow speed and adjust the idle mixture needle until the highest consistent RPM is attained Allow 15 seconds after each adjustment for the engine to respond5After the final adjustment is completed, turn the idle mixture needle counterclockwise one-eighth turn to prevent lean condition, particularly in NEUTRAL6Reduce engine speed and turn the idle speed adjustment to allow the engine to run at minimum of 825 RPM in FORWARD7Run the engine in gear near full throttle for one minuteQuickly reduce speed to SLOW and shift into NEUTRALThe engine should continue to run smoothly8If the engine stalls or pops, the mixture is too leanTurn the needle counterclockwise V16 turnAllow 15 seconds after each adjustment for the engine to respondRepeat Step to verify that the mixture adjustment is correct9Ifthe engine does not respond to adjustments, check it for other problemsMake sure gasoline is of good quality