Nanni N4.40, Workshop Manual

Page: 47 / 175

GENERAL
03-M-E3B, 03-M-DI-E3B, 03-M-E3BG, WSM
G-32
Check of Injection Pump
[D1803-M-DI, V2403-M-DI, V2403-M-DI-T]
Fuel Tightness of Pump Element
1. Remove the engine stop solenoid.
2. Remove the injection pipes and glow plugs.
3. Set the injection pump pressure tester to the injection pump.
4. Set the injection nozzle (2) jetted with the correct injection
pressure to the injection pump pressure tester (1). (Refer to the
figure.)
5. Set the speed control lever to the maximum speed position.
6. Crank the engine with the starter to increase the pressure.
7. If the pressure is lower than the allowable limit, replace the
pump with a new one.
You can also repair the pump at a Kubota-authorized pump
service shop.
Fuel Tightness of Delivery Valve
1. Remove the engine stop solenoid.
2. Remove the injection pipes and glow plugs.
3. Set the pressure tester to the fuel injection pump.
4. Set the injection nozzle (2) jetted with the correct injection
pressure to the injection pump pressure tester (1).
5. Crank the engine with the starter to increase the pressure.
6. Stop the starter when the fuel jets from the injection nozzle.
Then turn the flywheel manually and increase the pressure to
approximately 18.63 MPa (190.0 kgf/cm
2
, 2702 psi).
7. Turn the flywheel back about half a turn (to keep the plunger
free) and keep the flywheel at this position.
8. Measure the time for the pressure to decrease from 18.63 to
17.65 MPa (from 190.0 to 180.0 kgf/cm
2
, from 2702 to
2560 psi).
9. If the measurement is less than allowable limit, replace the
pump with a new one.
You can also repair the pump at a Kubota-authorized pump
service shop.
NOTE
• Do not try to disassemble the injection pump assembly.
Repair the pump at a Kubota-authorized pump service
shop.
M00000003GEG0047US1
Fuel tightness of pump
element
Allowable limit
18.63 MPa
190.0 kgf/cm
2
2702 psi
Fuel tightness of delivery
valve
Factory spec.
10 seconds
18.63
→ 17.65 MPa
190.0 → 180.0 kgf/cm
2
2702 → 2560 psi
Allowable limit
5 seconds
18.63
→ 17.65 MPa
190.0 → 180.0 kgf/cm
2
2702 → 2560 psi
(1) Injection Pump Pressure Tester
(2) Injection Nozzle (3) Protection Cover for Jetted Fuel
KiSC issued 06, 2009 A