Honda BF50 (5HP) BF5A Outboard Motors Shop Manual., Page 31Get this manual
FUELPUMP
[I] DIAPHRAGM
DISASSEMBLY: Push the diaphragm down and turn it until the foot is parallel with the groove in the push rodREASSEMBLY: Check the diaphragm for holes, deterioration and tearsReplace ifnecessary
[I]-1 DIAPHRAGM
1 PUSH ROD 3
REASSEMBLY: After assembly, press the push rod make sure it moves smoothly