Fuel pump system
Fuel pumps are a vital part of your engine, feeding fuel from the tanks to the injection system. They operate at a carefully controlled pressure specific to your engine model. Your engine may contain a variety of fuel pump systems, including:
Lift pumps
The lift pump is a low-pressure, high volume pump and is sometimes combined with a primary fuel filter or water separator system. Mechanical diaphragm pumps are mounted on the block and driven by the camshaft or auxiliary drive shaft. Alternatively, newer engines use electric lift pumps for improved reliability. Whatever the type, fuel pressure and delivery rate are critical for engine reliability.
Fuel injection pumps
The mechanical fuel injection pump delivers a precise amount of diesel fuel into each cylinder at exactly the right pressure. This is crucial to ensure the best power response to meet emission standards. Depending on the level of pressurisation in the fuel system different types of pumps are used. The common rail fuel injection pump’s purpose is to meter out fuel to the high-pressure common rail. This ensures the common rail has the correct fuel pressure, determined by the engine calibration required by the engine control system.
Rotary fuel pumps
These mechanical pumps use one pumping element to supply fuel to injector outlets. This may be a pair of plungers, four plungers or a single pumping plunger, depending on engine performance and fuel delivery requirements. With a flexible design capability these pumps can be used for a range of pressures to meet the performance demanded by increasing emissions standards. Higher emissions pumps now incorporate electronic control within the pump to enhance the injection timing control.
Inline fuel pump
Typically found on older large engines with low pressure systems, comprising a series of pumps mounted in one body. Each pump element feeds fuel to one cylinder in the engines, which are all controlled by a governor. Each element must be matched to the others for timing and fuel quantity, prior to adjusting the governor to match the desired engine control requirements.
Cassette type
The Perkins® 400 Series engines use a type of inline pump called a cassette type. To operate, the plungers rely on extra lobes being machined onto the camshafts. The fuel adjustment screw must be set correctly to comply with emission standards, and we recommend this is only carried out by an approved Perkins distributor.