BEARING-MAIN 0.5MM US-0.5MM OS 7C6965 - Caterpillar

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Delivery of fuel from the delivery valve
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Closing of the delivery valve
The delivery valve (15) ensures that the pressure waves do not allow a reopening of the fuel injection nozzle (10). The pressure waves are created at the end of the injection process. The valve cone is lifted by the fuel pressure. The fuel is forced through the fuel line to the fuel injection nozzle (10). The delivery ends and the fuel pressure drops. The valve spring presses the valve cone onto the valve seat. The reopening of a fuel injection nozzle (10) has a negative effect on emissions.Timing
Retarding of the fuel injection is the direct relationship between the start of injection and the position of the piston. The timing compensates for the higher RPM of the engine by advancing the start of injection.
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Timing advance for timing mechanism (side view and top view)
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Timing retard for timing mechanism (side view and top view)
The timing advance or the timing retard of the fuel injection pump is shown in the following steps:
The ECU (2) sends a signal to the timing solenoid valve (11).
The timing mechanism is triggered by the timing solenoid valve (11).
The timing solenoid valve (11) changes the pressure in the timing advance mechanism (12).
The timing advance mechanism (12) changes the position of the cam ring (5).
The cam ring (5) changes the position of the rollers (13).
The rollers (13) change the position of the cam plate (14).
The cam plate (14) changes the timing of the fuel delivery. Shutoff
The engine shuts off by interrupting the fuel supply. The engine Electronic Control Module (ECM) (1) specifies the amount of fuel. The fuel solenoid valve (6) is switched by the ECU (2) on the fuel injection pump to zero.Control
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Electronic control for the fuel system (typical example)
The ECU (2) for the injection pump uses the command from the ECM (1) and the measured values from the secondary speed/timing sensor (4) to actuate the fuel solenoid valve (6).
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The timing wheel and the secondary speed/timing sensor
(4) Secondary speed/timing sensor
(23) Timing wheel The ECU (2) for the fuel injection pump is mounted on the top of the pump. The ECU has a connection to the engine ECM (2) and a connection to the speed/timing sensor (4). The ECU has a connection for the two solenoid valves (6). The ECM functions as a control computer. The ECU calculates the optimal parameters from the ECM data. The fuel solenoid (6) actuates the valve accordingly.The secondary speed/timing sensor (4) in the fuel injection pump determines the precise angular position and the speed of the fuel injection pump shaft. Timing wheel (23) is permanently connected to the fuel injection pump shaft. The secondary speed/timing sensor (4) gets information from the timing wheel (23). The sensor then sends electrical impulses to the ECU (2). The ECU also uses the information to determine the average speed of the pump and momentary speed of the pump.Note: The engine will not run if the secondary speed/timing sensor (4) fails. The