Kubota WSM J Series Workshop Manual page 152

J SERIES, WSM
(B) Injection Nozzle
CAUTION
• Check the injection pressure and condition after confirming that there is nobody standing in the direction
the fume goes.
If the fume from the nozzle directly contacts the human body, cells may be destroyed and blood poisoning
may be caused.
Fuel Tightness of Delivery Valve
1. Remove the injection pipes and glow plugs.
2. Set a pressure tester to the fuel injection pump.
3. Turn the flywheel and raise the pressure to approx. 14.7 MPa
2
(150 kgf/cm , 2130 psi).
4. Now turn the flywheel back about half a turn (to keep the plunger
free). Maintain the flywheel at this position and clock the time
taken for the pressure to drop from 14.7 to 13.7 MPa (from 150
2
to 140 kgf/cm , from 2130 to 1990 psi).
5. Measure the time needed to decrease the pressure from 14.7 to
13.7 MPa (from 150 to 140 kgf/cm
6. If the measurement is less than allowable limit, replace the
delivery valve.
Fuel tightness of
Allowable limit
delivery valve
Fuel Injection Pressure
1. Set the injection nozzle to a nozzle tester (Code No. 07909-
31361).
2. Slowly move the tester handle to measure the pressure at which
fuel begins jetting out from the nozzle.
3. If the measurement is not within the factory specifications,
replace the adjusting washer (1) in the nozzle holder to adjust it.
Fuel injection pressure Factory spec.
(Reference)
• Pressure variation with 0.01 mm (0.0004 in.) difference of
adjusting washer thickness.
Approx. 235 kPa (2.4 kgf/cm
(1) Adjusting Washer
S-106
2
, from 2130 to 1990 psi).
5 seconds
14.7  13.7 MPa
150  140 kgf/cm
2130  1990 psi
13.7 to 14.7 MPa
140 to 150 kgf/cm
1990 to 2130 psi
2
, 34 psi)
ENGINE
2
W10403300
2
W10408820
KiSC issued 10, 2016 A