Checking The Vapor Shut-Off Valve - Yamaha F30B 2018 Service Manual

Checking the vapor shut-off valve

1. Measure:
• Vapor shut-off valve input voltage
Out of specification  Check the wire har-
ness for continuity.
Input voltage
12 V
Red/Yellow (R/Y)–Ground
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a. Disconnect the vapor shut-off valve cou-
pler "a".
b. Turn the engine start switch to ON, and
then measure the input voltage between
the vapor shut-off valve coupler terminal
and ground.
a
c. Turn the engine start switch to OFF.
d. Connect the vapor shut-off valve coupler.
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2. Check:
• Vapor shut-off valve operation
Not operating  Replace.
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a. Remove the vapor shut-off valve, and then
connect the special service tool "1" to the
vapor shut-off valve.
b. Apply the specified negative pressure to
the vapor shut-off valve.
c. Check that the vapor shut-off valve opens
and the negative pressure is released
when the battery leads are connected to
the vapor shut-off valve terminals.
Connect the battery leads to the vapor
shut-off valve terminals for only a few sec-
onds.
R/Y
d. Disconnect the special service tool.
e. Install the vapor shut-off valve.
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3. Measure:
• Vapor shut-off valve resistance
Out of specification  Replace.
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a. Disconnect the vapor shut-off valve cou-
pler.
b. Measure the resistance between the vapor
shut-off valve terminals.
c. Connect the vapor shut-off valve coupler.
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5-25
Fuel control unit and component
1
Vacuum/pressure pump gauge
set "1"
90890-06945
Pressure/vacuum tester "1"
YB-35956-B
Specified negative pressure
67.0 kPa (0.67 kgf/cm², 9.7 psi)
Resistance
30.0–34.0 