Replacement of glow plugs on diesel cars: instructions, car-care center services

Diesel engine glow plugs are designed to facilitate the start of a cold engine. These small devices heat the air in the combustion chambers even before the diesel engine is started. These parts increase the life of the unit, saving it from huge loads in cold weather.

Secondary roles

After starting and warming up the power unit, the candles receive secondary roles - they help to spray the fuel. Fuel that enters the combustion chamber by means of an injector collides with a candle. Creates a twist effect. This improves the formation of the mixture.

Device and types

The shape detail is similar to those used in gasoline engines. But the glow plugs do not produce sparks. At the heart of the candle is a heating element - a metal or ceramic spiral. One such piece can be heated to 1350 ° C in less than a second.

Heater made of metal

A metal heating element is two spirals. One - heating, the second - adjusting. The first function is the fastest possible heating of the tip. The second protects the part from strong overheating. This is possible, because with increasing temperature, the resistance on the adjusting spiral increases.

The free space between the heating tube and two spirals is filled with an insulator. It also performs several tasks - it protects the spiral from various mechanical damages and effectively transfers heat. A candle with a metal part can be heated up to 1000 °.

Ceramic Heater

This design is similar to the metal by the principle of action. Its structural feature is that the spiral is enclosed in a ceramic shell. Because of this, such an element will heat up more quickly. The power of this candle is also higher.

Principle of operation

So, the heating element is located on the cylinders of the power unit, wherever there are turbulences of the fuel mixture. When the driver turns the key in the lock, the voltage is applied to the candle and it heats up very quickly. This can be seen from the indicator on the dashboard. It takes about 5 seconds for the candle to fully run.

Then it is completely heated and warms the combustion chambers of the unit, as well as the air entering them. But these seconds are enough only for the self-heating of the candle. To warm up the air and cold parts of the cylinder block, as well as its head, the capabilities of this part is not enough.

So, the main function is to heat the fuel to such temperatures at which it can easily evaporate and ignite by compression.

Control system

Controls the operation of the relay either by the computer or a separate unit. The electronic unit can apply a different voltage to the candle, as well as control the temperature. The operation of electronics and relays is influenced by coolant temperature sensors, as well as the crankshaft speed.

In modern diesel engines, the candles, in addition to pre-heating, provide additional heat after start-up. This function allows you to significantly reduce the noise level at a time when the fuel burns on the unheated unit.

Malfunctions and their signs

Candles, like any other parts, fail. This can be determined by weak heating of the helix, the closure of the core by the mass, the closure between the core and the central core, burnout or breakage of the spiral. In many cases, replacement of the glow plugs with diesel cars is required .

Weak heating can be detected by the heating level of the helix of the control elements. The spiral on this element should be fully heated in 50 seconds. If the battery is in normal condition, then the cause of the malfunction may be in poor contact.

If the core is shorted to ground, this will lead to overheating, and then to burnout of the control elements, additional resistances or candles that are between the non-working and the control element. Also, due to a malfunction, the elements that are located behind the problem part can be disconnected. Therefore it is very important to know how to test the glow plugs, as then they are replaced if necessary.

Typical causes of malfunctions

A frequent and popular malfunction is burnout of the spiral. Detect this problem by the fact that the control element does not heat up. If you plug the metal conductor of the plug of the plug, you can see the spark. In this case, replacement of the glow plugs with diesel cars is necessary.

Often, such a malfunction as burnout can occur due to high filament currents, or too high a gas temperature, which is caused by a large amount of carbon deposit on the cylinder walls. Especially fast the spiral is destroyed due to corrosion.

Gaps in the heating spiral are the consequences of problems in the food system. This is due to inopportune injection, too low injection pressure, and others with other malfunctions. In this case, inspection and repair of diesel engines is already necessary.

Candle testing

When the weather is warm outside the window, the failure of the heating elements is practically invisible. Another thing is winter. There are two methods of verification. Each of them requires tools, skills, devices.

How to test glow plugs: method # 1

For testing, an insulated wire is needed. Then the candle is turned so that the heater is at the top. The central electrode is placed on the "+" battery. Wire connect the negative terminal and the candle body. If the element is heated quickly, then this part is OK. Nakala no or only the tip is heated - replacement of the glow plugs with diesel cars is required.

Method number 2

Often there is neither the time nor the tools to extract items from the cylinder head. So, the multimeter helps. The device is put into the resistance measurement mode. But before that, from the candle, detach the wire to the central element. Further - plus a multimeter is connected to the central electrode, minus - to the side of the case. No indications - replacement of the glow plugs with diesel cars is necessary.

Replacement

To dismantle, and then install a new candle on diesel units, you need to use a special tool, this is the head under M10. In addition, the installation should only be carried out with a torque wrench.

Dismantling is carried out strictly in order. The first step is to find out where the glow plugs are in the particular engine. Then wires are removed from them, and the well is cleaned with compressed air. Further - it is important to treat the element with grease or any other means from boiling. After that, a little oil is poured into the well. Then, with the help of a special key, they turn off the candles - the turn is smooth, without sharp impacts and loads. The place where the part was dismantled is cleaned and a new glow plug is installed. Its price depends on the manufacturer, but in any case it is small. For imported cars, it will be between 600 and 900 rubles at the current exchange rate.

Sometimes in the process of dismantling, there may be some problems. There is a situation when part of the product can be unscrewed, and the second remains in the cylinder head. Sometimes even after dancing with tambourines around the problem, the element refuses to get out. Do not try to uproot the candle - it's better to go back to where the diesel engines are being repaired.