1986+ Mercury 6/8/9.9/10/15HP 2-stroke Factory Service Manual, Page 133Get this manual
FUEL DELIVERY SYSTEM
Carburetor Adjustments
1Place outboard in water2Check tiller handle cable adjustment for full throttle movement in both Forward and Reverse gearsAdjust jam nuts for proper travel and to eliminate any slack
aAdjustment jam nuts INITIAL CARBURETOR ADJUSTMENTS Idle Speed Screw (Models So Equipped) 1Shift outboard to Neutral and place throttle twist grip to Slow2Push primerfast idle knob completely in and rotate knob fully counterclockwise3Back idle speed screw off of cam follower4Turn idle speed screw clockwise until it just touches cam follower, then inward an additional 12 turn to slightly open throttle plate