Fuel Injection Pump

The fuel injection pump is an opposed plunger, inlet metered, positive displacement, distributor type pump. Fuel under transfer pump pressure flows through the center of transfer pump rotor, past the rotor retainers into the hydraulic head. It then flows through a connecting passage in the head to the automatic advance and up through a radial passage to the metering valve. The position of the metering valve, controlled by the governor, regulates fuel flow into the radial charging passage which incorporates the head charging ports. As the rotor revolves, the 2 rotor inlet passages align with the charging ports in the hydraulic head, allowing fuel to flow into the pumping chamber.

With further rotation, the inlet passages move out of alignment and the rotor discharge port aligns with one of the head outlets. While the discharge port is opened, the rollers contact the cam lobes, forcing the plungers together. Fuel trapped between the plungers is then pressurized and delivered by the injector to the combustion chamber.