1995 Johnson Evinrude "EO" 9.9 thru 30, 2-Cylinder Service Manual, P/N 503146, Page 95Get this manual
Carburetor Mixture Adjustment, 2530
INote The slow speed mixture in this carburetor is controlled by
an adjustable needle
1Make reference mark on the carburetor body before you disturb the needle adjustment2Tiller modelsas you face the steering handle, turn idle speed adjustment knob counterclockwise to full SLOW speed position
3Start the engine and run it in gear, at slow speed (700-800 RPM), for three minutesAllow it to reach normal operating temperature If the adjustment is too lean, the engine will sneeze and backfireGo to Step Ifthe adjustment is too rich, the engine will be rough and unsteadyGo to Step 5
4If the adjustment is too lean, note your reference mark and turn the needle 1Ja revolution counterclockwiseWait 15 seconds after each adjustment and repeat this procedure until you reach the highest consistent RPM