1994 Johnson/Evinrude "ER" 9.9 thru 30 outboards Service Manual, Page 103Get this manual
Carburetor Mixture Adjustment, 2530 The slow speed mixture in this carburetor is controlled by an adjustable needle r:t61 1Make reference mark on the carburetor body before you disturb the needle adjustment
1171 2Tiller models -
as 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 5r:t61 4If the adjustment is too lean, note your reference mark and turn the needle Va revolution counterclockwiseWait 15 seconds after each adjustment and repeat this procedure until you reach the highest consistent RPM