2007-2009 Yamaha F15/F20 Outboard Service Manual, Page 79Get this manual
Fuel pump
Checking the fuel pump
1Connect the special service tool to the fuel pump inlet2Cover the fuel pump outlet with your finger, and then apply the specified positive pressureCheck that there is no air leakage
S6AG4100
Specified positive pressure: 50 kPa (0.5 kgfcm2, 7.3 psi)
Disassembling the fuel pump