Yamaha F100B F100C Outboards Factory Service Manual, Page 240Get this manual
Bracket unit
NOTE: To remove the free piston, blow compressed air through the hole while holding down the cloth8Remove the trim piston assemblies
Checking the reservoir
1Check the reservoir for cracksReplace if necessary4Check the trim and tilt rams for bends or excessive corrosionPolish with #400 600 grit sandpaper if there is light rust or replace if necessary
Checking the tilt cylinder and trim cylinder
1Check the power trim and tilt unit for cracks or corrosionReplace if necessary2Check the inner walls of the cylinder body for scratchesReplace if necessary