Figure 9
Working principle
72597
1. Cylinder. — 2. Three-lobe element. — 3. Cap intake valve. — 4. Ball delivery valve. — 5. Piston. — 6- Pump shaft. —
7. Low-pressure fuel inlet. — 8. Pumping elements supplying fuel ducts.
Sec. D-D
The pumping element (3) is orientated towards the pump’s
camshaft (4). During the intake phase, the pumping element
is fed through the feeding line (5). The quantity of fuel to flow
to the pumping element is determined by the pressure
regulating gauge (7). The pressure regulating gauge,
according to the PWM command received by the engine
control module, stops the fuel flow to the pumping element.
During compression phase of the pumping element, the fuel
achieves the level of pressure determining the opening of the
by-pass valve to common rail (2), feeding it through the
exhaust unit (I).
Sec. B-B
10
SECTION 2 - FUEL
F4HE NEF ENGINES
Base - February 2006
Print P2D32N00GB