Yamaha F100B F100C Outboards Factory Service Manual, Page 243Get this manual
Tilt cylinder and trim cylinder (F100B) Installing the tilt ram
1Fill the tilt cylinder with the recommended fluid to the correct level as shown2Add small amount of the recommended fluid through the cylinder body hole as shown
WARNING
To prevent the power trim and tilt fluid from spurting out due to internal pressure, the tilt ram should be kept at full lengthNOTE: Place the tilt cylinder end screw at the bottom of the tilt ram and install the tilt piston assembly into the tilt cylinder