1997 Johnson Evinrude "EU" 9.9 thru 30 2-Cylinder Service Manual, P/N 507263, Page 45Get this manual
2Tiller ModelsTurn the idle speed knob fully counterclockwise to the full SLOW position
3Start the engine and allow it to reach normal operating temperature4When speed is reduced, engine must idle at 700 25 RPM in FORWARD gearStop the engine
5Adjust the idle speed screw to change idle speed
6Tiller ModelsRemove throttle cable bracket screwAdjust the throttle cable bracket to provide slight preload against the idle speed screw when the Twist-Grip is held at the full SLOW position7Run engine in gear at, or near, full throttle for one minuteQuickly reduce speed to SLOW (700-800 RPM) and shift into NEUTRALEngine should continue to run smoothly8If engine stalls or backfires, the idle mixture is too leanRefer to Carburetor Adjustment, Section 2Shift Lever Detent Adjustment