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High pressure fuel pump (pump)
| Fig. 3.18. Details of the high-pressure fuel pump 1 - the drive shaft; 2 - supply of fuel; 3 - overpressure valve of the fuel pump; 4 - lever fuel supply; 5 - a centrifugal regulator; 6 - drainer fuel .; 7 - the valve of a stopping delivery of fuel; 8 - the fuel supply to the injector; 9 - plunger distributor; 10 - lifting disc; 11 - shot controller (for clarity deploy 900); 12 - roller ring; 13 - low-pressure fuel pump
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High pressure fuel pump shown in Fig. 3.18 is a key element in the power supply system of diesel engines. Pump, mounted on cars Golf III, - distribution, odnoplunzherny, mechanical centrifugal speed controller, automatic control of fuel injection, ignition systems. The drive pump is provided by the timing belt. The pump rotates at a speed half that of the crankshaft of the engine, supplies fuel to the large positive pressure to the nozzles. All diesel engines point fuel injection timing is set by changing the position of the injection pump on the support bracket, but the engine 1Z it shall be adjusted only by means of special test equipment - if necessary, you should consult a maintenance disposing such equipment. The primary supply of fuel to the high pressure pump housing provides fuel pump low pressure plate type, draws oil from the fuel line. Compression and fuel supply to the injectors carried out by means of the plunger distributor, located on the same shaft as the rotor of the low pressure pump. The plunger is permeated with lots of holes and recesses, whereby it can carry out two functions: filling and injection.
| Fig. 3.19. A pump filling phase 1 - plunger; 2 - the electromagnetic valve engine stop; 3 - an inlet; 4 - Managing the gap; 5 - a drain pipe; 6 - nozzle
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During filling fuel Managing gap 4 (Fig. 3.19) is located opposite the opening 3 of the input channel. The fuel boost pump low pressure enters the space under the plunger. Driven by a toothed belt from the crank shaft of the plunger is rotated, thus the fuel supply from the input channel is terminated - this fuel supply cycle ending.
| Fig. 3.20. Pump in the phase of the fuel supply to the nozzle: 1 - the electromagnetic valve engine stop; 2 - plunger; 3 - hole, opening pressure line; 4 - pressure line; 5 - a drain pipe; 6 - pipe; 7 - Injector
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After the end of the phase of filling the plunger is rotated and shown in Figure lifting lug disc impinges on the roller wheel roller. In this way, a distributor plunger, which is now rigidly connected to the lifting disc moves back and the pressure in the pump circuit rises sharply. At this point, the opening 3 (fig. 3.20) of the distributor is in a position coinciding with a backbone of high pressure, and the fuel in now under high pressure gets to the injector 7, which injects. Excess fuel flows back to the tank through the drain pipe 5. From the hole filling again enters the fuel when the plunger distributor is rotated to the outlet of the next cylinder. Speaking at the hoisting drive again runs onto the roller ring, plunger distributor moves forward and injects fuel in the next cylinder. It should be noted that the pump cars of release since October 1994 is controlled by the control unit, which automatically monitors the status of the pump and registers in the memory of all the faults that have arisen in the course of his work. Service and identification of faults such pump is only possible with a special diagnostic equipment.
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