Mercury Mariner Service Manual 6, 8, 9.9 210CC Sailpower, Page 35Get this manual
TimingSynchronizing Adjusting Maximum spark advance 36 BTDC (3 Dots) Idle timing BTDC Idle speed RPM 550-650This motor does not have an idle adjustment screwThe carburetor is calabrated to run at the recommended idle speed1Place engine in water2Check tiller handle cable adjustments for full throttle movement in forward and reverse gearsAdjust jam nuts for proper travel and eliminate any slack 3Properly adjust carburetor low speed mixture screwRefer to "Carburetor Adjustments" Section
MAXIMUM SPARK ADVANCE ADJUSTMENT 1Connect timing light to No.1 (top) spark plug lead2With engine running in forward gear, advance engine speed to full throttle3Adjust screw (a) to obtain specified maximum spark advance timingRetighten jam nut