1991 Yamaha Outboard Factory Service Manual 9.9 and 15 HP, Page 51Get this manual
POWER HEAD DISASSEMBLY COl magneto 1Remove the starter pulley2Loosen the flywheel nut using the flywheel magneto holder and 22 mm socket wrenchKeep the nut side flush with the crankshaft end until the flywheel comes off the tapered portion of the crankshaft
WARNING:
The flywheel magneto holder must be held so that the major load is carried by the straight endThe correct use of the flywheel magneto holder