subject: Basic Knowledge Of The Spark Plug And Attention [print this page] Any gasoline engine has a spark plug, a cylinder, the high-speed petrol engine for each individual cylinder is also equipped with two spark plug. Although only a small spark plug is a part, but it is extremely important, without it the engine will not move. Those who often drive people will be very familiar with this stuff.
The role of spark plug ignition coil to generate the high voltage (10,000 volts or more) into the engine cylinder, the spark plug electrode gap between the spark ignited the mixture. Spark plug work environment is extremely harsh, with a typical four-stroke gasoline engine spark plug, for example, when the temperature in the intake stroke is only 60 , pressure 90KPa; combustion in the ignition, the temperature will rise instantly to 3000 , the pressure to 4000KPa; This rapid thermal quench alternating high frequency, not the usual material can handle it, but also ensure the insulation, so the spark plug of material requirements also very harsh.
Spark plug is very small, one can put away a few pockets, but it is not a simple structure. Insulator and metal shell which has two components: the metal shell with a screw thread for screw into the cylinder; in the shell that has the insulator, it was a center electrode inside through the center electrode top of a wire nut, connect from the Distributors over the power lines; the end under the shell welding grounding electrode, the center electrode and ground electrode gap between 0.6-1.0 mm, high voltage through the gap into the earth would burst out spark ignition mixture.
The key part of the spark plug insulator, does not work if the insulator, high voltage will in lieu of poles into the ground, causing no sparks. Spark plug insulators must have good mechanical properties and resistance to high voltage, high-temperature impact resistance, chemical corrosion ability, more than ordinary spark plug used to made of alumina-based ceramics. Spark plug size is uniform throughout the world, any car can be common, but different types of gasoline engines, the spark plug will have two basic types of points, type of cold and hot type.
Type and heat and cold are relative terms, it reflects the thermal characteristics of spark plug performance. Spark plug have the right temperature to work well without coke to work properly. Proven spark plug insulator to maintain the temperature at 500-600 , the fall of the oil droplets insulator will not immediately burn off the coke formed, higher than the temperature of early burning, lower than the temperature coke. At different engine temperatures will be different, the designer on the use of insulator length skirt to resolve this contradiction. Some short skirt heated area small, fast heat dissipation, so skirt the temperature lower, is called cold type spark plug for high-speed high-power engine with high compression ratio; some slender skirt heated area, heat slowly, so skirt temperature is higher, known as thermal-type spark plug for the low compression ratio in the low-speed low-power engine. What spark plug in his car, according to the manufacturer's requirements models to choose from, not a spark plug are applicable.
Spark plug this thing looks simple, not easy to do, it requirements of materials and manufacturing processes is very high, due to very poor working conditions, the breakdown spark plug insulator, electrode coke failure often occurs, it is "wearing parts "Many drivers toolbox standing spark plug to change at any time. Of course, with the technology, the durability of spark plug have improved, use platinum alloy electrode materials to replace traditional copper - nickel alloy, extended life spark plug, spark plug generally used modern car mileage up to about 150,000 km.
Select spark plug into account more factors, such as engine type, cooling method, stroke number, fuel grade and use of environmental temperature and other common conditions. General motorcycle, automobile spark plug factory model has been determined, the mounting dimensions match, the user can according to the ambient temperature, road conditions, machinery old and new spark plug heat value of the choice. Made under standard conditions, such as spark plug heat value of commonly used models of 5, when the temperature is below 5 , the value should be used as low-level heat to ensure spark plug, spark plug operating temperature skirt. The old engine, the use of low-level spark plug heat value may be due to mechanical abrasion resistance of the spark plug channeling oil pollution.
Spark Plug serious erosion. Spark plug from the top of scars, damage or electrode melting, erosion has destroyed all that spark plug should be replaced. Ablation of the disease should be replaced as well as checking the color change, in order to analyze the causes of production.
Spark plug with sediment. Spark plug insulator between the electrodes on top and sometimes sticky deposits, the engine can cause serious, such as clean spark plug can be temporary remedy. In order to maintain good performance, to identify the root causes of failure.
