Checking The Fuel Pump; Disassembling The Fuel Pump - Yamaha F50F Service Manual

Checking the fuel pump

1. Disconnect the fuel hoses from the fuel
pump.
2. Connect the special service tool to the
fuel pump inlet.
3. Cover the fuel pump outlet with a finger,
and then apply the specified positive
pressure. Check that there is no air leak-
age.
Vacuum/pressure pump gauge set:
90890-06756
Specified pressure:
50 kPa (0.5 kgf/cm
4. Apply the specified negative pressure
and check that there is no air leakage.
Specified pressure:
30 kPa (0.3 kgf/cm
5. Connect the special service tool to the
fuel pump outlet.
6. Apply the specified positive pressure and
check that there is no air leakage. Disas-
semble the fuel pump if necessary.
6C13G11
S6C14050
2
, 7.3 psi)
S6C14060
2
, 4.4 psi)
Fuel filter and fuel pump
NOTE:
Assemble the fuel pump valve to the fuel
pump body, and moisten the inside of the fuel
pump with gasoline to ensure a good seal.
Specified pressure:
50 kPa (0.5 kgf/cm

Disassembling the fuel pump

1. Disassemble the fuel pump.
2. Push down on the plunger and the dia-
phragm, turn fuel pump body 1 1
approximately 90° to a position where the
pin 2 can be removed easily, and then
remove the pin.
3. Slowly let up on the plunger and dia-
phragm, and then remove them.
1
2
S6C14070
3
2
, 7.3 psi)
4
5
6
7
8
9
4-6