Some people think that the maintenance of oil trucks is to change the oil, which is very one-sided and wrong. The maintenance of oil trucks is a broad concept, including the replacement and cleaning of the oil and filter of the engine system (oil, gear oil, brake oil, self-variable oil, power oil, antifreeze, glass water, battery water, machine filter, steam filter, air filter, air conditioning filter, etc.), and the replacement and maintenance of the wearing parts of oil trucks, such as belts, spark plugs, batteries, tires, brake pads, ball heads, clutch pieces.
The service life of the spark plug is 15000km, and the service life of the long-acting spark plug is 30000km. The function of the spark plug is to introduce the pulsed high-voltage electricity generated by the ignition coil into the combustion chamber, and use the electric spark generated by the electrode to ignite the mixture and complete the combustion. The model of domestic spark plug is composed of three parts of numbers or letters. The number in front indicates the thread diameter, such as the number 1, indicating that the thread diameter is 10mm, and the middle letter indicates the length of the spark plug into the cylinder part; The last digit indicates the hot type of the spark plug: 1-3 is hot, 5, 6 is medium, and 7 and above is cold. The "gap" of the spark plug is its main working technical index, the gap is too large, the high voltage generated by the ignition coil and the distributor is difficult to skip, which makes the engine difficult to start; If the gap is too small, it will lead to weak sparks and easy leakage.
Spark plug common failure has the following two situations: spark plug serious ablation, spark plug top scar, damage or electrode melting, ablation indicate that the spark plug has been destroyed, should be replaced. The spark plug has deposits, the top of the spark plug insulator and the electrode will sometimes stick to the sediment, which will cause the engine to not work seriously, such as cleaning the spark plug can be temporarily remedied, but the root of the fault must be identified.
Spark plug inspection:
1. Disassembly: Remove the high pressure branch line on the spark plug in turn, and mark it in the original position to avoid misplacement. In the disassembly, pay attention to remove dust and debris at the spark plug hole in advance to prevent debris from falling into the cylinder. When disassembling, use the spark plug sleeve to fasten the spark plug, turn the sleeve to remove it, and arrange it in turn.
2, check: the normal color of the spark plug electrode is grayish white, such as the electrode burned black and accompanied by carbon deposition, it indicates that there is a fault. During the inspection, the spark plug and the cylinder block can be switched on, and the central high-voltage wire can be used to contact the terminal post of the spark plug, and then the ignition switch can be opened to observe the high-voltage jump position. If the electric jump position is in the spark plug gap, it means that the spark plug works well, otherwise, it needs to be replaced.
Spark plug electrode gap adjustment: various models of spark plug gap are different, generally should be between 0.7-0.9, check the size of the gap, can be used spark plug gauge or thin metal sheet. If the gap is too large, the screwdriver handle can be used to gently tap the outer electrode to make the gap normal; If the gap is too small, a screwdriver or metal plate can be inserted into the electrode to pull outwards.
Spark plug replacement: Spark plug is a consumable part, generally traveling 20,000-30,000 kilometers should be replaced. The mark of spark plug replacement is that the spark plug does not jump fire, or the electrode discharge part is circular due to ablation. In addition, if the spark plug is often found in use of carbon, broken fire, generally because the spark plug is too cold, need to replace with a hot spark plug; If there is hot ignition phenomenon or impact sound in the cylinder, you need to choose a cold type spark plug.
Spark plug cleaning: spark plug oil or carbon should be cleaned in time, but do not use flame barbecue. If the porcelain core is damaged or broken, it should be replaced.
Many people know that the spark plug should be replaced regularly, but they ignore the maintenance of other parts of the ignition system, and the ignition high-voltage cable is one of them.