MANIFOLD AS-PUMP 3P0890 - Caterpillar

Illustration 1 g02166133
Fuel system schematic
(1) Fuel gallery
(2) Mechanical electronic unit injectors
(3) Fuel pressure regulators
(4) Fuel return line
(5) Fuel cooler (if equipped)
(6) Tank breather filter
(7) Fuel tank
(8) Fuel supply line
(9) Fuel/water separator
(10) Electric fuel priming pump
(11) Fuel transfer pump
(12) Check valve
(13) Electronic control module (ECM)
(14) Fuel temperature sensor
(15) Pressure relief valve
(16) Secondary fuel filter
(17) Differential pressure switch (If equipped)
(18) Tertiary fuel filter
(19) Fuel pressure sensor (If equipped)
(20) Secondary fuel filter base The fuel supply circuit is a conventional design for unit injector diesel engines. The system consists of the following major components that are used to deliver low-pressure fuel to the unit injectors:Fuel tank - The fuel tank is used to store the fuel.Fuel priming pump - The fuel priming pump is used to evacuate the air from the fuel system. As the air is removed, the system fills with fuel.Fuel filters - The fuel/water separator is a 10 micron filter with a water separator. This filter is used to remove abrasive material and contamination from the fuel system that may be large enough to damage the fuel transfer pump. The secondary fuel filter, which is located on the secondary fuel filter base, is used to remove abrasive material and contamination. As small as 2 microns that could damage the injectors. The tertiary fuel filter is located on the secondary fuel filter base. The tertiary fuel filter is used to remove abrasive materials and contamination as small as 4 microns. A differential pressure switch is utilized on the secondary fuel filter base in order to indicate the life of the fuel filter.Supply lines and return lines - Supply lines and return lines are used to deliver the fuel to the different components.The purpose of the low-pressure fuel supply circuit is to supply fuel that has been filtered to the fuel injectors at a rate and a pressure that is constant. The fuel system is also utilized to cool components such as the fuel injectors.Once the injectors receive the low-pressure fuel, the fuel is pressurized again before the fuel is injected into the cylinder. The unit injector uses mechanical energy that is provided by the camshaft to achieve pressures that can be in excess of 200000 kPa (30000 psi).Control of the fuel delivery is managed by the Electronic Control Module (ECM) of the engine. Data from several of the engine systems is collected by the ECM and processed in order to manage these aspects of fuel injection control:
Injection timing
Fuel injection timing advance
Injection duration
Engine cold mode status The mechanical electronic fuel system relies on a large amount of data from the other engine systems. The data that is collected by the ECM will be used in order to provide optimum performance of the engine.Low Pressure Fuel Supply Circuit
The flow of fuel through the system begins at fuel tank (7). Fuel that is drawn from the tank by the fuel transfer pump (11) is filtered through a fuel/water separator. The separator is a 10 micron filter with a water separator. Fuel flows from