Mercury Mariner 4 and 5HP 4-Stroke Outboards Service Shop Manual 1999, Page 58Get this manual
IGNITION SYSTEM
INSTALLATION
1Install flywheel key (a)2Install flywheel (b), washer (c) and nut (d) onto end of crankshaft
3Secure flywheel holder (a) to flywheel with bolts (b)4Torque Ilywheel nut to 40 lbft (54.0 Nm)