Honda Outboards BF40A/BF50A Service Manual, Page 410Get this manual
BF40A-BF50A 10) Remove the 2-way valveRemove the O-ring from the 2-way valve and discard itReplace the O-ring with new one during reassembly[1] O-RING
Do not reuse
[2] 2-WAY VALVE
b.INSPECTION
DOWN RELIEF VALVE Check the down relief valve seat, spring guide, steel ball and spring for wear and damageReplace the down relief valve seat, spring guide or spring if damaged or worn UPPER CHAMBER SAFETY VALVE Check the upper chamber safety valve for wear and damageReplace the upper chamber safety valve if damaged or worn
[2] SPRING
[3] UPPER CHAMBER SAFETY VALVE
[1] SPRING GUIDE
[5] STEEL BALL [4] DOWN RELIEF VALVE SEAT