Yamaha F100B F100C Outboards Factory Service Manual, Page 182Get this manual
Lower unit
Removing the lower unit
1Drain the gear oilFor draining procedures, see Chapter 3, "Changing the gear oil 2Set the gearshift to the neutral position, and place block of wood between the anti-cavitation plate and propeller to keep the propeller from turning, and then remove the propeller nut and propeller
S60C6390
WARNING