Honda BF8, BF9.9 and BF10 Outboard Motors Shop Manual., Page 189Get this manual
4) Reinstall the piston rings into the piston groovesPush in
the ring until the outer surface of the piston ring is nearly flush with the piston and measure the side clearance using feeler gaugeStandard
Service limit
TOP second Oil
0.0250.055 mm (0.00100.0022 in) 0.0550.1 40 mm (0.00220.0055 in)
0.10 mm (0.004 in) 0.20 mm (0.008 in)
dASSEMBLY
1) Clean the piston and carefully install the piston rings
Take care not to damage the piston ring by spreading the ends too farBe careful not to damage the piston during the piston ring removalClean carbon deposits from the piston ring grooves with ring that will be discardedNever use wire brush; it will scratch the groovesDo not confuse the top and second ringsThe top ring is chrome-coated and second not coatedInstall the top and second rings with the mark facing UP Oil ring; first install the spacer then install the side rails2) After installing the ring make sure that they rotate freely,