Yamaha Marine Outboards Factory Service / Repair/ Workshop Manual 225G 250B L250B, Page 48Get this manual
INSP ADJ
LOWER UNIT
E Filling steps (1) Place the outboard in an upright position(2) Insert the gear oil tube into the drain hole and slowly fill the gear oil until oil flows out of the check hole and no air bubbles are visible(3) Install the gear oil level check screw and then quickly install the gear oil drain screwGear oil level check screw Nm (0.7 kgf, 5.1 ft lb) Gear oil drain screw Nm (0.7 kgf, 5.1 ft lb)
INSPECTING THE LOWER UNIT (FOR AIR LEAKS)