On a cold engine, the ignition temperature of the fuel cannot be reached by compression alone. In this case, heating (preheat) engine. To do this, each swirl chamber of a diesel engine has a glow plug that heats up the combustion chamber.
Fuel is sucked directly by the high pressure fuel injection pump (injection pump) from the fuel tank. The pump generates the necessary high pressure (about 130 bar) and the fuel is distributed to the cylinders according to the ignition sequence. At the same time, the injection pump regulator doses the fuel supply depending on the degree of engagement of the gas pedal. At a certain point in time, diesel fuel is injected through nozzles into the prechamber of the corresponding cylinder. Depending on the shape of the prechamber or swirl chamber, the intake air acquires a swirling motion under the influence of compression, which contributes to optimal mixing of air and injected fuel.
Before entering the high pressure fuel pump, the fuel passes through the fuel filter. There it is cleaned of dirt and water. Therefore, it is especially important to drain the water from the filter or replace it in accordance with the maintenance schedule.
The high pressure fuel pump is maintenance free. All moving parts of the pump are lubricated with diesel fuel. The pump is driven via a toothed belt.
Being self-igniting, the diesel engine cannot be switched off by removing the ignition voltage and has a solenoid valve for this. When the ignition switch is turned off, power is removed from the valve and it closes the fuel supply channel. This ensures that the fuel supply is interrupted before the steering wheel locks when the ignition key is removed. When the engine is started, voltage is applied through the ignition switch to the solenoid valve and it opens the fuel supply channel.
Attention! Keep cleanliness when working on the diesel injection device.