2006 SD Johnson 4 Stroke 9.9-15HP Outboards Service Manual, Page 215Get this manual
GEARCASE SHIMMING ADJUSTMENTS
Forward GearPinion Gear
Correctly assemble forward gear, pinion gear, driveshaft, and related componentsRefer to ASSEMBLY on p209Check that slight amount of backlash exists between pinion gear and forward gear by slightly rotating driveshaft or forward gear by hand If there is no backlash, reduce back-up shim thickness If there is too much backlash, increase back-up shim thickness
Rotate the driveshaft clockwise 5-6 times by hand
Pull out propeller shaft and housing to check tooth contact patternApprox13 of tooth width Approx1 mm HEEL
Gear Tooth Contact Pattern
Apply light coat of Prussian Blue on the convex surface of forward gearInstall propeller shaft and housing assembly (minus reverse gear and internal components)Push propeller shaft inward and hold in position