Yamaha F150B Service Manual page 50

TECH
FEA
System chart
After running through the fuel filter, the fuel is sent to the vapor separator by the fuel pump attached
to the cylinder head cover and driven by the camshaft.
Then, the fuel is pressurized by the electric fuel pump within the vapor separator, runs through the
pressure regulator to the fuel rail, and injected into the combustion chamber through the fuel injector.
The pressure regulator is installed at the outlet of the electric fuel pump to make the design compact
and to allow simple delivery of the fuel.
The fuel discharged from the pressure regulator is cooled down by the fuel cooler, and sent back to
the vapor separator.
The pressure check valve is installed on the fuel rail for improved serviceability of the fuel system.
j #1
j #2
j #3
j #4
a
b
A
Fuel flow
a
Primer pump
b
Fuel filter
c
Fuel pump
d
Fuel filter
e
Vapor separator
2-7
Technical features and description
h
i
k
a
f
g
g
j
c
f
High-pressure fuel pump
g
Pressure regulator
h
Fuel rail
i
Fuel cooler
j
Fuel injector
k
Pressure check valve
b c
e
d
f
i
h k
d
e
A