Yamaha F100B F100C Outboards Factory Service Manual, Page 283Get this manual
Tilt cylinder and trim cylinder (F100C)
3Check the outer surface of the tilt piston and free piston for scratchesReplace if necessary
4Install the backup ring and O-rings and into the trim cylinder end screw 8
4Check the tilt ram for bends or excessive corrosionPolish with #400600 grit sandpaper if there is light rust or replace if necessary
5Install the trim cylinder end screw onto the tilt ram
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