Checking The Fuel Pressure - Yamaha MBK MW125 2014 Service Manual

• Fuel hose connector cover
ECA17500
NOTICE
When installing the fuel hose, make sure that
it is securely connected, and that the fuel
hose connector cover on the fuel hose is in
the correct position, otherwise the fuel hose
will not be properly installed.
TIP
• Wipe up any fuel remaining in the recess "a" in
the fuel pump with a dry rag "1".
• After installing the fuel hose connector cover
"2", make sure that it is installed securely.
EAS30703

CHECKING THE FUEL PRESSURE

1. Check:
• Pressure regulator operation
▼ ▼▼▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼
a. Remove the fuel hose connector cover "1",
and then remove the fuel hose "2" from the
fuel pump.
EWA18020
WARNING
Cover the fuel hose connection with a cloth
when disconnecting it. Residual pressure in
the fuel lines could cause fuel to spurt out
when removing the hose.
ECA21750
NOTICE
• Be sure to disconnect the fuel hose by
hand. Do not forcefully disconnect the
hose with tools.
1
2
▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼
• Although the fuel has been removed from
the fuel tank, be careful when removing the
fuel hose, since there may be fuel remain-
ing in it.
• Do not disconnect the fuel hose from the
fuel hose connector. Disconnect the con-
nector from the fuel pump.
TIP
Before removing the hose, place a few rags in
the area under where it will be removed.
a
b. Connect the pressure gauge "3" and fuel
pressure adapter "4".
3
▼▼▼
c. Start the engine.
d. Measure the fuel pressure.
Faulty → Replace the fuel pump.
e. Connect the fuel hose and install the fuel
hose connector cover.
7-3
FUEL TANK
1
Pressure gauge
90890-03153
Pressure gauge
YU-03153
Fuel pressure adapter
90890-03181
Fuel pressure adapter
YM-03181
Fuel line pressure at idling
300–390 kPa (3.0–3.9 kgf/cm²,
43.5–56.6 psi)
2
4
2