How to purchase and maintain automobile spark plugs

Generally speaking, the normal service life of a spark plug can range from 2,000 kilometers to 150,000 kilometers depending on its material and manufacturing process. Due to the harsh working environment, spark plugs are prone to failures and normal expendable failures often occur, so it belongs to the “vulnerable consumables” on the car.

Although today’s cars are equipped with advanced spark plugs such as platinum spark plugs, they do not need to be replaced frequently like the copper spark plugs in the past; however, the parts of the spark plugs still need to be inspected every once in a while. If the spark plug is rusted, the spark plug gap is too large, or the car has not been replaced after 50,000 kilometers, it is almost time to replace it.

When the spark plug is worn, fouled, or the gap is missing, a “poor ignition” situation may occur, such as the spark plug cannot produce sparks, the engine cannot start or the engine runs unsmoothly. Once the spark plug fails, it is likely to cause a decline in the overall performance of the engine and the car. Therefore, it is very important to understand the working efficiency and duration of spark plugs, to make the correct selection, use and maintenance, and to clean and replace them in time when there is a malfunction. It is very important to ensure the good operation of the car. Through regular inspection and timely replacement, it can help you save unnecessary repair costs.

Choose the model correctly

The selection and replacement of spark plugs should first determine the quality of the spark plug and its matching degree with the engine, including the engine model, cooling method, stroke number, fuel label, use environment temperature and common working conditions, etc., so it needs to be based on the specifications, calorific value, and ignition gap. , Brand, price and other aspects to comprehensively choose.

1, size:

There are certain differences in the specifications and dimensions of spark plugs due to factors such as diameter, length, and electrode length. Generally speaking, the corresponding car has already determined the spark plug model when leaving the factory, so first choose the spark plug with the same appearance and size.

2, calorific value:

In addition to different appearances and sizes, spark plugs are divided into three types: cold, medium, and hot according to their calorific value. The heat value of the spark plug represents the heat dissipation speed, the higher the heat value, the colder the spark plug. If the heating value of the spark plug is too low, it will cause deflagration and burn the ceramic of the spark plug head. If the broken ceramic falls into the engine, it is easy to cause danger and the electrode is easy to dissolve; Charcoal, running out of electricity, or no fire.

Generally speaking, cold spark plugs should be used for engines with high compression ratio and high speed; hot spark plugs should be used for engines with low compression ratio and low speed, and medium-sized spark plugs can be used for those in between.

In addition, the selection of the calorific value of the spark plug is also different according to the actual conditions such as the ambient temperature, road conditions, new and old machines in the area.

3. Ignition gap:

Different cars and engines will specify the corresponding best ignition gap. After being used for a period of time, the spark plug will change the ignition gap due to normal wear or other factors. At this time, it should be replaced in time.

If the ignition gap selected is incorrect, it may have a harmful effect on the function of the spark plug and the performance of the engine. If the gap is too small, it may cause misfiring, noisy operation and poor exhaust; if the gap is too large, a higher ignition voltage is required so that the spark plug can skip this gap, which may cause misfire.

Clean charcoal and decontamination in time

During the use of the spark plug, there will be normal carbon deposits on the electrode and skirt insulator, which should be cleaned in time. If these carbon deposits are not treated for a long time, they will accumulate to a certain extent, which will cause the electrode to leak or even fail to spark. Therefore, carbon deposits should be removed regularly (usually 3000 km to 5000 km) to ensure the normal operation of the spark plug. At the same time, when the spark plug is oily, it should be cleaned in time.

When cleaning the carbon deposits and oil stains on the surface of the spark plug, special cleaning equipment and corresponding solutions should be used instead of sandpaper, metal sheets, etc. for convenience and speed. The correct treatment method is to use special cleaning equipment, which will have a good cleaning effect; second, when cleaning with a solution, you can first put the spark plug in alcohol or gasoline for a certain period of time, and then use the wool after the carbon deposits are softened. Brush and dry, so as to ensure that the ceramic body on the outside of the spark plug is not damaged.

It should be noted that when removing the carbon deposits and oil stains on the spark plug electrodes and skirts, fire cannot be used. Although this method is effective on the surface, it is easy to cause damage to the spark plug. Because the temperature is difficult to control when the fire is burning, it is easy to burn the skirt insulator, causing spark plug leakage, and the small cracks produced after the fire are often difficult to find, which will bring a lot of trouble to troubleshooting.

Replacement timing

After a certain number of years of use, the spark plug should be replaced in time, otherwise it will be detrimental to the power and economy of the engine. Generally speaking, ordinary spark plugs should be inspected or replaced after driving 10,000 kilometers or 1 year. Platinum spark plugs and iridium spark plugs can be replaced within 100,000 kilometers without inspection.

According to related studies, as the service life of the spark plug is prolonged, the end surface of the center electrode will change to a circular arc shape, and the side electrode will change to a concave arc shape. This shape will increase the electrode gap and cause discharge (that is, spark generation). ) Difficulties, affecting the normal operation of the engine. Therefore, after reaching the rated service life of the spark plug, it should be replaced in time.

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