2007-2009 Yamaha F15/F20 Outboard Service Manual, Page 38Get this manual
Maintenance specification Item Rocker arm shaft Outside diameter Rocker arm Inside diameter Valve Valve clearance (cold) Intake Exhaust Head diameter (A) Intake Exhaust Face width (B) Intake Exhaust Seat contact width (C) Intake and exhaust Margin thickness (D) Intake Exhaust Stem diameter Intake Exhaust Stem runout limit Guide inside diameter Intake and exhaust Stem-to-guide clearance Intake Exhaust Guide installation position Valve spring Free length Tilt limit Cylinder Bore size Unit mm (in) mm (in) Model F20PHF F20PRF
12.94112.951 (0.50950.5099) 13.00013.018 (0.51180.5125)
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) mm (in) mm (in)