1991 Yamaha Outboard Factory Service Manual 9.9 and 15 HP, Page 126Get this manual
Maintenance specifications
1Engine
Item Cylinder head: Warp limit 9.9N 15N
0.1 mm (0.0039 inLines indicate straightedge measurement
Cylinder: 80re size Taper limit Out of round limit Piston: Piston size Measuring point Piston clearance Oversize 1st 2nd Offset Piston ring: Sectional sketch
56 mm (2.20 in) 0.08 mm (0.003 in) 0.05 mm (0.002 in) 56 mm (2.20 in 10 mm (0.39 in) 0.0350.040 mm (0.00140.0016 in) 56.25 mm (2.21 in 56.25 mm (2.22 in
Top ring
2nd ring
Keystone-0.01 mm -0.03 (0 079 -0.0004 )
Plain-0.01 mm