2005 YAMAHA VX110 Service Manual

4-12
EFUEL
THROTTLE BODY ASSEMBLY AND INTAKE
MANIFOLD
SERVICE POINTS
Fuel hose clamps removal
1. Remove:
Fuel hose clamps
CAUTION:
If the fuel hose clamps are removed with-
out cutting the joint first, the fuel hose will
be damaged.
Hose clamps installation
1. Install:
Fuel hose clamps
WARNING
Do not reuse the fuel hose clamps, always
replace them with new ones.
NOTE:
Crimp the fuel hose clamps properly to
securely fasten them.
Fuel hose disconnection
WARNING
Before disconnecting the hose, remove the
fuel tank filler cap to reduce any pressure
inside the fuel tank, and then disconnect
the battery negative lead to cut off the elec-
tric current to the electrical systems.
1. Wrap the quick connector with a cloth, and
then rotate the quick connector tab 1
to
the stopper position a
.
WARNING
If the quick connector is removed sud-
denly, pressurized fuel could spray out. To
gradually release the fuel pressure, be sure
to remove the quick connector slowly.
1
a
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4-13
EFUEL
CAUTION:
Do not rotate the quick connector tab
1
past the stopper position, otherwise it
could be damaged.
When the fuel hoses are disconnected,
quickly remove the retainer
2 from the
quick connector, otherwise the retainer
could be lost.
2. Disconnect the fuel hose 1
from the fuel
pipe 2
directly.
WARNING
Always reduce the fuel pressure in the fuel
line before servicing the line or the fuel
pipe. If the fuel pressure is not released,
pressurized fuel could spray out.
21
1
2
3. Cover the quick connector and fuel pipe
with a plastic bag 3 to prevent damage
and to protect them from dirt.
3
Fuel line inspection
1. Inspect:
Fuel hose
Damage/cracks → Replace.
O-rings (quick connector)
Damage/cracks → Replace the quick
connector.
Fuel pipe
Damage/cracks → Replace the fuel
pump.
THROTTLE BODY ASSEMBLY AND INTAKE
MANIFOLD
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4-14
EFUEL
THROTTLE BODY ASSEMBLY AND INTAKE
MANIFOLD
Fuel hose installation (replacing with new
fuel hose)
1. Install:
Fuel hose 1

NOTE:
To install the fuel hose, be sure to align the
white mark a
of the fuel hose with the
checker tab 2
of the quick connector.
When replacing the fuel hose with a new
one, a checker tab 2
that has half engage-
ment prevention is attached to the quick con-
nector of the hose. If the quick connector is
completely installed to the fuel pipe, it is
removable.
2
1a
2
Fuel hose connection
1. Apply a thin coat of engine oil to the con-
tact surfaces of the fuel pipe.
2. Insert the quick connector into the fuel
pipe until you hear a “click.”
3. To check the connection of the quick con-
nector, push and pull on the quick connec-
tor several times until there is free play of
2–3 mm (0.08–0.12 in).
NOTE:
If free is not obtained, disconnect the fuel hose
and check the O-ring for damage and that it is
properly installed.
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4-15
EFUEL
THROTTLE BODY ASSEMBLY AND INTAKE
MANIFOLD
Fuel injectors inspection
NOTE:
Do not remove the throttle body assembly.
1. Check:
Fuel injectors
Dirt/residue →
Clean.
Damage →
Replace.
2. Measure:
Fuel injectors resistance
Out of specification →
Replace.
3. Check the operation of the fuel injector
using the “Stationary Test” of the Yamaha
Diagnostic System.
Digital multimeter:
YU-34899-A
Digital circuit tester:
90890-03174
Fuel injector resistance:
(reference data)
11.5–12.5
Ω at 20 °C (68 °F)
Throttle body assembly inspection
CAUTION:
The throttle body assembly should not be
disassembled.
1. Check:
Throttle body assembly
Cracks/damage →
Replace the throttle
body assembly.
Accelerator position sensor inspection
1. Inspect:
Accelerator position sensor
Damage/cracks →
Replace the acceler-
ator position sensor.
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4-16
EFUEL
THROTTLE BODY ASSEMBLY AND INTAKE
MANIFOLD
Intake assembly installation
1. Install:
Intake screw clamp
Intake manifold joint
Intake assembly
NOTE:
Install the intake screw clamp in the direction
shown in the illustration, making sure to align
the indentation in the clamp with the projec-
tion a
on the intake manifold joint.
Tighten the clamp screw until both ends of
the intake screw clamp contact the spacer 1
around the screw.
a
11
2. Install:
Fuel hose 2 (fuel rail side)
Fuel hose clamps
WARNING
Do not reuse the fuel hose clamps, always
replace them with new ones.
NOTE:
Install the fuel hose with the white mark a
facing up.
Install the fuel hose clamps at the locations
shown in the illustration, and then crimp
them to securely fasten them.
2a
8 mm (0.31 in) 6 mm (0.24 in)
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4-17
EFUEL
THROTTLE BODY ASSEMBLY AND INTAKE
MANIFOLD
Air filter case assembly installation
1. Install:
Air intake duct 1

Air intake hose 2

Air filter case cover
NOTE:
Align the projections a
on the air intake duct
and air intake hose with the projections b
on
the air filter case cover as shown in the illustra-
tion.
2. Adjust:
Throttle lever free play
Refer to “CONTROL SYSTEM” in Chap-
ter 3.
a
b a
b
2
1
Fuel pressure measurement
1. Disconnect:
Fuel hose
Refer to “Fuel hose disconnection”.
2. Install:
Fuel pressure gauge adapter 1

Fuel pressure gauge 2

NOTE:
To connect the fuel pressure gauge adapter,
follow the procedures for connecting a fuel
hose. (Refer to “Fuel hose connection”.)
3. Start the engine and arrow it to warm up
for several minutes.
4. Measure:
Fuel pressure
Out of specification →
Replace the fuel
pump module.
Fuel pressure gauge adapter:
YW-06842/90890-06842
Fuel pressure gauge:
YB-06766/90890-06786
Fuel pressure:
320–327 kPa
(3.2–3.3 kgf/cm
2, 46–47 psi)
2
1
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4-18
EFUEL
5. Remove:
Fuel pressure gauge
Fuel pressure gauge adapter
NOTE:
To disconnect the fuel pressure gauge
adapter, follow the procedures for disconnect-
ing a fuel hose. (Refer to “Fuel hose discon-
nection”.)
6. Connect:
Fuel hose
Refer to “Fuel hose connection”.
THROTTLE BODY ASSEMBLY AND INTAKE
MANIFOLD
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