Yamaha F100B F100C Outboards Factory Service Manual, Page 101Get this manual
Power unit 10Measure the valve pad thickness with micrometerSelect the necessary valve pad by calculating its thickness with the following formulaNecessary valve pad thicknessRemoved valve pad thicknessMeasured valve clearance Specified valve clearance Example: If the "Removed valve pad thickness" is 2.10 mm, the "Checked valve clearance" is 0.30 mm and the "Specified valve clearance" is 0.20 mm, then the necessary valve pad thickness2.100.30 0.202.20 mm 11Install the necessary valve pad into the valve lifter12Install the camshafts, camshaft caps, driven sprockets, and timing belt, and then tighten the tensioner boltCamshaft cap bolt: 1st: Nm (0.8 kgfm, 5.8 ftlb) 2nd: 17 Nm (1.7 kgfm, 12 ftlb)
S60C3280
CAUTION:
Do not turn the flywheel magnet counterclockwise, otherwise the valve system may be damaged Do not remove the ignition timing pointer17Install the timing belt, and then tighten the tensioner bolt finger tight18Turn the flywheel magnet clockwise two turns, and then check that the alignment marks are aligned19Tighten the tensioner bolt to the specified torqueTensioner bolt: 39 Nm (3.9 kgfm, 28 ftlb)