HIGH-PRESSURE FUEL PUMP 24-VOLT POWER SUPPLY CONNECTOR REGULATOR VALVE LOW-PRESSURE FUEL INLET CHECK VALVE AND FILTER DRIVEN GEAR (BREAK AWAY) FUEL RETURN PORT The majority of the fuel entering the high-pressure pump is directed to high pressure pumping units for pressurization to the required operating pressure. There are eight pumping units shown in Figure 16, which are operated by the eccentric camshaft rings and controlled by inlet and outlet check valves. Fuel enters the pumping unit through the inlet check valve, pressurized by the piston to the high operating pressure, then exits through the outlet check valve to the accumulator.
There are two high-pressure outlet ports for transferring the pressurized fuel to both the A-bank and B-bank high-pressure rails. Page 18 HIGH-PRESSURE ACCUMULATOR HIGH-PRESSURE FUEL OUTLET PUMPING UNITS Fig. 16 High-pressure Fuel Pump Assembly