1998 Mercury 9.9/15HP 4-stroke outboards factory service manual, Page 126Get this manual
CARBURETOR
4Move throttle linkage forward until linkage comes to rest on the pulley boss
a-Throttle Linkage b-Pulley Boss 5Tighten screw on throttle barrel to secure linkage
NOTE: Over-tightening screw may damage throttle linkageNOTE: Check linkage for free movement on pulleyVerify throttle shaft arm in not sticking and returns to idle positiona-Screw b-Linkage 6Verify throttle arm does not hit the full throttle stop at wide open throttleGap between stop and throttle arm should be no more than 0.1 in(2.54 mm)