Yamaha F100B F100C Outboards Factory Service Manual, Page 144Get this manual
Power unit
11Install the new gasket and exhaust cover, and then tighten the bolts to the specified torques in two stages and in the sequence shown
S60C5B50
Exhaust cover bolt: 1st: Nm (0.6 kgfm, 4.3 ftlb) 2nd: 12 Nm (1.2 kgfm, 8.7 ftlb)
Installing the power unit