Honda BF8, BF9.9 and BF10 Outboard Motors Shop Manual., Page 120Get this manual
INLETJOUTLETVALVE INSTALLATION 1) Install the inlet valve (has the pin) at the side marked
"+"on the priming bulb
r21 OUTLET VALVE
1I INLET
2) Install the outlet valve (has the valve seat) at the.other sideDo not confuse the inlet valve with the outlet valveInstall the priming bulb with the mark toward the motor side