Checking The Fuel Pump And Pressure Regulator Op- Eration; Checking The Throttle Position Sensor - Yamaha XF50W Service Manual

THROTTLE BODY AND FUEL INJECTOR
EAS00915
CHECKING THE FUEL PUMP AND PRES-
SURE REGULATOR OPERATION
1. Check:
8 pressure regulator operation
• • • • • • • • • • • • • • • • • • • • • • •
a. Remove the footrest board.
Refer to "COVER AND PANEL" in chapter
3.
b. Remove the fuel hose connector cover
and disconnect the fuel hose
fuel pump.
C
Although the fuel has been removed from
the fuel tank, be careful when removing the
fuel hose, since there may be fuel remaining
in it.
NOTE:
Before removing the hose, place a few rags in
the area under where it will be removed.
c. Connect the pressure gauge
(4) onto the fuel hose.
(tj//^ Pressure gauge
/f~"^ 90890-03153
YU-03153
Adapter
90890-03181
d. Start the engine.
e. Measure the fuel pressure.
Fuel pressure
246 ~ 254 kPa
^
(2.46 ~ 2.54 kg/cm
Faulty -» Replace the fuel pump.
• • • • • • • • • • • • • • • • • • • • • • •
EAS0091 6
CHECKING THE THROTTLE POSITION SEN-
SOR
1. Check:
8throttle position sensor
• • • • • • • • • • • • • • • • • • • • • • •
a. Connect the digital circuit tester to the ter-
minals of the throttle position sensor.
7-32
FI ifl
(T)
(2) from the
(3) and adapter
2
, 35.0 ~ 36.1 psi)