Yamaha F30B 2018, Service Manual

Page: 128 / 348

6-1
Fuel system
Fuel system
Reducing the fuel pressure
Before servicing the high-pressure fuel line
or vapor separator, make sure to reduce
the fuel pressure in the fuel line. Otherwise,
pressurized fuel could spray out.
1. Reduce:
• Fuel pressure
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a. Remove the fuse holder cover “1”, and
then remove the main fuse (30 A) “2”.
b. Start the engine.
TIP:
After removing the main fuse, wait until the en-
gine stalls.
c. After the engine stalls, crank the engine 2
or 3 times.
d. Turn the engine start switch to OFF.
e. Install the main fuse (30 A), and then install
the fuse holder cover.
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Disconnecting the quick connector
Before disconnecting the quick connector,
reduce the fuel pressure. Otherwise, pres-
surized fuel could spray out.
Cover the fuel components using a rag to pre-
vent fuel from spilling out.
1. Disconnect:
• Quick connector
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a. Reduce the fuel pressure. See “Reducing
the fuel pressure” (6-1).
b. Wrap a rag around the quick connector “1”.
c. Disconnect the quick connector “1”.
TIP:
Cover the quick connector and fuel rail with a
plastic bag to prevent damage and dirt from
entering them.
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Measuring the fuel pressure
Cover the fuel components using a rag to pre-
vent fuel from spilling out.
1. Measure:
• Fuel pressure
Out of specification

Check the fuel line.
2
1
Fuel pressure at engine start
switch to “ON” within 3 seconds
280 kPa (2.8 kgf/cm², 40.6 psi)
Fuel pressure at idle speed
230 kPa (2.3 kgf/cm², 33.4 psi)
1