For what car spark plug

To start the engine, it is necessary to ignite the mixture in the cylinders. For this, a spark plug is used, between the electrodes of which a spark arises, which ignites the mixture in the engine of the car. The normal start and operation of the engine largely depends on the state of the candles.

Any spark plug has a steel casing. On its lower part there is a thread for screwing the candle and its side electrode into the chamber part. Inside the body of the candle, in the sealed insulator there is a metal rod, it serves as the central electrode. On its upper part there is a thread for bringing the tip of the armored tube. The basis of the candle is a ceramic insulator.

For correct and long-term operation, the lower part of the insulator with the engine running should reach a temperature of up to 600 ^° C. Under these conditions, complete combustion of the oil occurs, which falls on the electrodes, and no deposits are formed. With this temperature mode, the candles are self-cleaning.

If the temperature is lower, the oil does not completely burn, and a carbon monoxide is formed on the electrodes, insulator and the candle casing. The result of this is the failure of its operation, the disappearance of the supply of a spark (the discharge can not break through the layer of deposits). In such cases, ignition occurs, that is, the fuel mixture is ignited not from the electro-spark, but from interaction and direct contact with the red-hot parts of the candle.

The structural features of the central electrode and insulator divide the candles into cold (with the greatest heat emission) and hot (with low heat output). The ability to accumulate heat characterizes the glow plug number. It is indicated on the candle and means the time (in seconds), after which there will be a glow ignition.

Every car owner caring for his car knows how to check the spark plugs for dirt and deposits. With a well-running engine, properly tuned carburetor / injector and ignition, with proper operation of the candles themselves, you can see on them deposits of light brown color.

The appearance of a light gray or whitish coating on the cone of the insulator indicates the presence of such problems as a small octane number of fuel, overheating of the candles due to improper installation of ignition, poor composition of the working mixture.

Dry black loose deposit indicates re-enrichment of the mixture, late ignition, rather frequent operation of the engine idle. If you adjust the ignition system, the deposit will disappear.

Oily black coating is a sign of a cold candle. The spark does not appear on it, or there is no compression in the cylinder, and it does not give the put power, as a result of which the engine runs unevenly.

Red-brown deposits on the cone of the insulator are the result of the combustion of fuel, which contains many additives. This spark plug must be replaced or mechanically cleaned.

It can be safely said that the spark plug is non-working, if: its thread in the oil, the rim of the body is covered with loose black carbon, dark brown spots on the electrodes and insulator, chips and burnup on the cone of the insulator. Oiled candles in the engine with a huge mileage indicate the wear of pistons, cylinders, rings.

Reduce and eliminate various troubles will help qualified car service, every 15-20 thousand km, and timely troubleshooting.