FUEL SYSTEM
Electronic Control System
6-38
6LY3 Service Manual
© 2007 Yanmar Marine International
Injection Quantity Control Diagram
The ECU (Engine Control Unit) controls the fuel injection quantity and injection timing. Injection quantity
control is done through the rack position control of the fuel injection pump. The injection quantity control
diagram by ECU is shown in
Figure 6-48
.
Figure 6-48
Figure 6-48
1/4
2/4
3/4
4/4
Boost pressure
Fuel oil
temperature
Coolant
temperature
Throttle position
Crank speed
Rack position
Input
Output
Target speed calculation
depend on throttle position
Target governor position calculation
basically depend on target speed and actual speed
(Starting only)
Engine speed
target cal.
Load
Speed
Idle
Rack actuator
Rack position
feedback calculation
Engine speed
governor cal.
Rack position
control cal.
Compensation
valve
0005712