Yamaha F100B F100C Outboards Factory Service Manual, Page 241Get this manual
Tilt cylinder and trim cylinder (F100B) Installing the trim rams
1Hold the cylinder body in vise using aluminum plates on both sides5Fill the trim cylinders with the recommended fluid to the correct level as shown
S60C7500
2Add the specified amount of the recommended fluid through the cylinder body hole b
6Add small amount of the recommended fluid though cylinder body holes d, e, and f
Recommended power trim and tilt fluid: ATF Dexron II Fluid quantity: 30 cm3 (1.0 US oz, 1.1 Imp oz) 3Install the new O-ring and backup ring to the free piston 44Push the free piston into the tilt cylinder until it bottoms out