Ford Sierra

4.2.3.1. Роторный the fuel pump of a high pressure

THE GENERAL DATA

The power supply system scheme

1 – дозатор, 2 – the electromagnetic fuel valve, 3 – the pumping up pump, 4 – a regulator of pressure, 5 – atomizers,

6 – an atomizer in a cut, 7 – rotorno-plunzhernyj knot of distribution of fuel in the fuel pump of a high pressure

On a pump shaft two are established плунжерные steams submitting under a high pressure fuel in cylinders of the engine. Плунжеры receive progress at the expense of influence on them of a figured profile located in the pump. The quantity of fuel submitted to cylinders is regulated дозатором, an operated cable from an accelerator pedal. The corner of an advancing of injection changes depending on engine turns the mechanical centrifugal regulator which has been built in in ТНВД.

For an engine stop there is an electromagnetic valve. At engine start on a valve winding pressure 12 moves In, the valve opens and passes fuel to the pump and atomizers. At engine deenergizing, key turn in the ignition lock switches off the fuel valve and fuel giving is blocked. The fuel pump under a high pressure through pipelines, submits fuel to atomizers which are established in a head of the block of cylinders about combustion chambers. Atomizers inject fuel into vortical chambers in which there is a fuel ignition. Atomizers represent the valve which opens at strictly certain pressure of fuel (110–120 bar). The spray which is on the bottom end of an atomizer, forms a torch of sprayed fuel of the demanded form. Отсечка fuel it is made by a needle under the influence of an atomizer spring. The spray and a needle are knot of precision accuracy and demand the accurate reference at repair. Surpluses of fuel after отсечки filter along a needle, greasing it and, on the return pipeline are taken away in a tank.

Serviceability and correct adjustment of atomizers are very important for normal work of the engine. If the spray of an atomizer does not provide a torch of the demanded form or occurs bad отсечка, the engine starts to work with vibration, there are strong mechanical knocks, raises дымление.

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The prevention

Pressure of injection is adjustable parametre. During operation of the engine of pressure of injection often falls, therefore the atomizer is necessary for checking periodically and if necessary to regulate. It is necessary to notice that sprays from different models of engines are outwardly identical, but have different characteristics, in particular, the torch form, therefore new sprays should be applied only what are calculated on the given model.

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Two independent systems are applied to investment of start of the cold engine. One of systems at cold start-up supports the raised turns of idling, before engine warming up. It consists of a temperature-sensitive element established in a head of the block of cylinders, a cable in a cover and systems of levers on the fuel pump, On the cold engine the gauge tightens a cable, thereby, raising turns. At heating the working body of the gauge extends and releases a cable, thus on the heated-up engine the normal mode of idling is established.

The second system serves for improvement of ignition of fuel in cylinders at the moment of start-up. In vortical chambers of each cylinder candles накаливания are established. Before engine start on them pressure that shows fire of a control bulb on a combination of devices moves. Within several seconds of a candle are heated to a heat and the control bulb dies away that serves as a signal for engine start. The heated candles lift temperature in the vortical chamber and facilitate fuel ignition. It is necessary to notice that candles are disconnected not right after engine start, and after a while, allowing the engine to leave on normal operating conditions.

Failure even one candle conducts to the complicated start of the engine, with faults in work and strong vibration. The fuel system on diesel engines is usually very reliable. The basic condition of normal and durable work is cleanliness of used fuel and absence in it of water.