BOLT 1520604 - Caterpillar

Illustration 1 g01140556
Flow diagram of the fuel system
(1) Fuel injection nozzles
(2) Electronic fuel priming pump and secondary fuel filter
(3) Fuel injection pump
(4) Primary fuel filter/water separator
(5) Fuel tank
(6) Fuel return line
(7) Fuel supply line The 3054E engine is equipped with a Bosch VP30 fuel injection pump. This pump is an axial piston distributor injection pump that is controlled by the Electronic Control Module (ECM).The axial piston distributor injection pump generates injection pressure for all cylinders in a single pump. The injection pump is responsible for the distribution of fuel to the fuel injection nozzles. The injection pressure is generated by an axially moving piston. The movement of the piston is parallel to the fuel injection pump shaft.When the engine is cranking, the fuel is pulled from fuel tank (5) through primary fuel filter/water separator (4) by fuel priming pump (2). When the fuel passes through the water separator, any water in the fuel will go to the bottom of the bowl. The fuel priming pump is equipped with a secondary fuel filter. From the fuel priming pump, the fuel passes through the fuel supply line to fuel injection pump (3). The fuel injection pump sends fuel through the high pressure fuel lines to fuel injection nozzles (1). The fuel injection nozzles spray atomized fuel into the cylinder.The fuel injection pump needs fuel for lubrication. The precision parts of the pump are easily damaged. The engine must not be started until the fuel injection pump is full of fuel. The system must be primed when any part of the system is drained of fuel. The fuel system needs priming when a fuel filter is changed, and/or when a fuel line is removed, and/or when the fuel injection pump is replaced.Fuel Injection Pump
Illustration 2 g01140815
Schematic of the Bosch VP30 fuel injection pump
(1) ECM
(2) Electronic Control Unit (ECU) for the fuel injection pump
(3) Fuel priming pump
(4) Speed/timing sensor
(5) Cam ring
(6) Fuel solenoid valve
(7) Pressure regulator
(8) Distributor plunger
(9) Fuel transfer pump
(10) Fuel injection nozzle
(11) Timing solenoid valve
(12) Timing advance mechanism
(13) Roller
(14) Cam plate
(15) Delivery valve The fuel injection pump has the following operations:
Delivery
Generation of high pressure
Distribution and injection
Timing
Shutoff
ControlDelivery
Illustration 3 g01140827
Center view of the Bosch VP30 fuel injection pump
(9) Fuel transfer pump Fuel is supplied by the head pressure of the priming pump. The fuel enters fuel transfer pump (9) of the fuel injection pump. The fuel transfer pump is a vane pump. The transfer pump is driven by the fuel injection pump shaft. The pump supplies a constant amount of fuel to the interior of the fuel injection pump. The revolution of the transfer pump is directly related to the speed of the fuel injection pump shaft.
Illustration 4 g01140857
Fuel transfer pump for the Bosch VP30 fuel injection pump
(5) Cam ring
(16) Pump housing
(17) Outlet passage
(18) Rotor
(19) Vane
(20) Inlet passage Rotor (18) rotates inside cam ring (5). The ring is firmly attached to pump housing (16). Vanes (19) are pressed against the ring by centrifugal force. The fuel flows through inlet passage (20) then into a recess in