Yamaha Outboard Motors Factory Service Manual F6 and F8, Page 58Get this manual
MAINTENANCE SPECIFICATIONS Model World wide USA, Canada Face width "B" IN EX Seat width"C" IN EX Mergin thickness "D" IN EX Stem outside diameter IN EX Valve guide inside IN diameter EX Stem-to-guide clearance IN EX Stem runout limit IN EX VALVE SPRING Free length Free length limit Tilt limit Item Unit mm (in) mm (in) mm (in) mm (in) mm (in) mm (in) mm (in) mm (in) mm (in) mm (in) mm (in) mm (in) mm (in) mm (in) mm (in) mm (in) F6AMH, F6BMH F8CMH, F8CW F6MH F8MH 1.842.26 (0.0720.089) 1.842.26 (0.0720.089) 0.60.8 (0.0230.031) 0.60.8 (0.0230.031) 0.7 (0.027) 1.0 (0.039) 5.4755.490 (0.21560.2161) 5.4605.475 (0.21500.2156) 5.5005.512 (0.21650.2170) 5.5005.512 (0.21650.2170) 0.0100.037 (0.00040.0015) 0.0250.052 (0.00100.0020) 0.03 (0.0012) 0.03 (0.0012) 27.6 (1.09) 27.6 (1.09)