Injection Quantity Control Diagram - Yanmar 6LY3 series Service Manual

FUEL SYSTEM

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
Boost pressure
Fuel oil
temperature
Coolant
temperature
Throttle position
Crank speed
Rack position
1/4
Idle
6-38
(Starting only)
Engine speed
target cal.
Engine speed
governor cal.
4/4
3/4
2/4
Speed
© 2007 Yanmar Marine International
Target speed calculation
depend on throttle position
Target governor position calculation
basically depend on target speed and actual speed
Rack position
control cal.
Figure 6-48
Electronic Control System
Rack actuator
Rack position
feedback calculation
6LY3 Service Manual
Input
Output
0005712