Yamaha Outboards 3P Service Manual, Page 46Get this manual
ASSEMBLY AND ADJUSTMENT
G72001 -0
PISTON 1) Install the 2nd piston ring into the 2nd ring groove with the marking facing upward2) Install the keystone ring into the top ring groove with the marking facing upward3) Align each ring end-gap with their locating pins
G7300 1-0