Mercury Force 9.9, 15HP Outboards Service Manual, Page 224Get this manual
FADJUSTING STEERING HANDLE (Throttle Control) 1Set magneto control lever at W.O.TpositionPull steering handle shaft (A) so steeri ng handle gear (8) fits against bearing (C) and meshes with magneto control shaft gear (0)
NOTE: Make sure hole at other end steering handle shaft is horizontalSlide steering hand le shaft retainer (E) against steering handle bearing and torque set screw (F) in retainer to 45 inIbs(4.9N m)