Fuel Injection Pumps - Yamaha Z250D Service Manual

Fuel injection pumps

Twin fuel injection pumps with pressure regulators have been adopted to obtain a high fuel pressure
2
of 7 MPa (71 kg/cm , 1,015 psi).
The fuel injection pressure is detected by the fuel pressure sensor installed on the fuel rail. Protec-
tors have been incorporated on the fuel pressure sensor to reduce vibrations conducting to the sen-
sor.
High-pressure fuel injection obtains a better air-fuel mixture due to finer atomization.
CAUTION:
Do not disassemble the fuel injection pumps. The proper facilities and special service tools
are required to reassemble them.
8
0
B
1 Fuel pump drive unit
2 High-pressure fuel pump with
pressure regulator
3 Fuel return hose
4 Pressure equalizing pipe
5 Fuel pressure sensor
6 Fuel rail
60V3E11
1
3
2
5
6
7 Injector #1
8 Injector #2
9 Injector #3
0 Injector #4
A Injector #5
B Injector #6
4
: È
: É
: Ê
È Medium-pressure fuel
(suction)
É High-pressure fuel
Ê Fuel return
Features and benefits
2
3
7
9
A
S60V1150
1
2
3
4
5
6
7
8
9
1-8