2003 Johnson ST 6/8 HP 4 Stroke Outboards Service Manual, PN 5005471, Page 156Get this manual
POWERHEAD ASSEMBLYHP into placeTap until installer contacts the powerheadon camInstall screw, with washer, in the end of the camDO NOT torque at this time
Apply Gasket Sealing Compound to both sides of new cylinder head gasketPlace cylinder head and gasket in position on cylinder block, apply Four-Stroke Outboard Break-In Lubricant to cylinder head screws, and torque to 18 to 20 ftIbs(24 to 27 Nm) in stages in the sequence shown
Install pulley key in crankshaft parallel with centerlineInstall belt guide and pulleyTap pulley in place using socket and hammer