27
COMPILER TECO/ATI
ENDORSED
DATE
23.06.2003
REG. CODE
1-5302-607
MODEL N°
50889
DATE OF ISSUE
06-03
REVISION
00
XI
38
41
40
39
23 ÷ 25 cc 20 ÷ 22 cc (BOSCH)
INJECTION EQUIPMENT
Fuel circuit
Fuel feeding can be either gravity type or forced, with a mechanical
double diaphragm pump operated a cam located on the camshaft.
Fuel is filtered by a filter in the fuel tank or through an external filter
cartridge.
The fuel circuit is bled of air automatically.
Components of figure 38:
1. Fuel tank - 2. Fuel filter - 3. Fuel supply lines - 4. Fuel injection
pumps - 5. Bleed off connection - 6. Fuel injectors - 7. Injection lines
- 8. Fuel return lines - 9. Fuel sully pump.
Injection pumps
Components of figure 39:
1. Delivery connection - 2. O-ring - 3. Filler - 4. Washer - 5. Valve
spring - 6. Delivery valve - 7. Injection plunger - 8. Lower plate - 9.
Spring - 10. Top plate - 11. Retaining ring - 12. Adjustment sleeve -
13. Pump body - 14. Sleeve securing pin - 15. Distance ring - 16.
Eccentric pin - 17. Cap - 18. Clip for BOSCH pump type PF30.
Checking injection pumps
Before dismantling the injection pumps check for pressure leak of
the pumping unit, plunger and valve, as follows:
1. Connect a pressure gauge with 600 Kg/cm² full scale to the
diesel delivery line (fig.40).
2. Set the control sleeve (nr. 12, fig.39) to a mid-point delivery
position.
3. Turn the flywheel slowly until the plunger has completed a full
compression stroke.
4. Take the pressure gauge reading. If it is below 300 Kg/cm² the
complete plunger unit must be changed.
During the test the reading on the gauge will show a progressive
pressure increase to a maximum value and then will fall suddenly
and stop at a lower pressure. Replace the valve if the fall in
pressure exceeds 50 Kg/cm² and continues to fall slowly.
The pressure drop from 200 Kg/cm² to 150 Kg/cm² must occur in a
time interval of no less than 7 seconds.
Injection pump setting (fig.41)
Set the maximum quantity delivered by the pump by turning the
eccentric pin using a screwdriver (nr. 16, fig.39).
With the control sleeve at 10mm from the stop position and the
pump running at 1,500 rpm, the quantity of fuel for 1,000 shots must
be between:
