The difference between spark plugs: single, 2, 3 and 4 pin
Content
According to most motorists, such candles are the best choice in terms of price / quality ratio. They have 2 side electrodes in their design, which do not cover the tip and do not strongly prevent hot gases from cleaning the insulator body. The flame from the spark evenly enters the combustion chamber, ensuring stable operation of the piston.
If the question arises, how do single-contact candles differ from 2, 3 and 4-contact, then the answer is obvious - the number of side electrodes. In addition, models with multiple "petals" have a longer service life.
What do single-pin candles give
These products are now the most common. They are popular due to their low cost and low fuel quality requirements. Such candles work well in the engines of most cars: from used domestic cars to new foreign cars.
The design of the model is quite simple:
- Above is a white ceramic case.
- Below is a metal glass with a thread.
- The tip, over which hangs 1 "petal".
The product is easily screwed into the candle well. The gap between the main and side electrodes is usually 0,8-1,1 mm. This distance increases over time as the metal wears away with each discharge of the coil, resulting in misfiring.
How to choose spark plugs
Therefore, the main disadvantages of single-contact candles are:
- low resource reserve (copper and nickel products are enough for a run of 15-30 thousand km);
- instability in sparking (especially in winter).
To ensure reliable flame formation and increase the charge power, manufacturers reduce the diameter of the tip (from 2,5 to 0,4 mm). Additionally, it is coated with an alloy of noble metals (platinum, iridium, yttrium), which reduces the wear rate by 2-3 times. Also, in order to reduce the extinguishing effect and ensure a more complete combustion of the fuel, a U-groove is applied to the side contact, and a V-shape is given to the central electrode.
Distinctive features of spark plugs
To reduce product wear, manufacturers, in addition to using precious materials, began to produce models with several electrodes. The most popular products are Ngk, Bosh, Denso, Brisk.
Three-pin
This type of spark plug is commonly used in mid-price car engines. They guarantee a stable flame formation, but are very demanding on the quality of the fuel. With bad gas, they will last no longer than ordinary candles.
Some experts claim that the life of 3-contact products is several times longer than that of single-contact products. Indeed, the side "petals" are erased evenly, as the spark strikes alternately into the nearest one as they wear out. But it is important to understand that the central tip is subjected to electrical erosion first of all. Its margin of safety depends on the material. For example, if the spike is made of iridium, then the product will last up to 90 thousand kilometers.
Two-contact
According to most motorists, such candles are the best choice in terms of price / quality ratio. They have 2 side electrodes in their design, which do not cover the tip and do not strongly prevent hot gases from cleaning the insulator body. The flame from the spark evenly enters the combustion chamber, ensuring stable operation of the piston.
Four-pin
In the design of these products, there are 2 pairs of electrodes with a gap of 0,8 mm and 1,2 mm, respectively. Due to this structure, candles are suitable for most carburetor and injection engines.
Various spark plugs
These candles are worse than other models, they are cleaned of soot and create less flame at low speeds. But on the other hand, they have the largest resource reserve (especially with iridium sputtering). This is due to the fact that 4 side contacts are ground from electrical discharges in turn. In addition, they do not cover the space above the tip, which ensures an even distribution of fire from the spark. Because of this, the load on the piston walls is balanced.
Some car owners claim that after installing multi-electrode candles, they noticed the following:
- there are no problems with starting the car even in winter;
- increased engine power by 2-3%;
- reduced fuel consumption by 0,4-1,5%;
- the exhaust gases decreased by 4-5%.
In addition, some engines are designed for single-contact with the location of the "petal" above the tip, so that the discharge is along the axis. Other motors require side clearance. Therefore, the choice of a suitable model should be carried out together with a specialist, otherwise problems will arise in the operation of the motor.
