Yamaha 40V Manuel D'utilisation page 150

EMK23511
Flushing cooling system
8 Flushing in a water tank
1) Fit the outboard motor on the water
2) Shift into Neutral, start the engine,
cC
If the fresh water level is below the level
of the anticavitation plate, or if the water
supply is insufficient, engine seizure may
occur.
1 Water surface
2 Lowest water level
605024
4-7
tank, and fill the tank with fresh water
to above the level of the anti-cavita-
tion plate.
and run at low speed for a few min-
utes.
GB