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List of catalogs of this article:

• 1, Is the engine cylinder block and cylinder head cast?
• 2, car cylinder head deformation Handling method
• 3, What causes the broken cylinder head
• 4、What circumstances do you need to change the cylinder head

Is the engine cylinder block and cylinder head cast?

The engine cylinder head is an important part, usually made of cast iron or aluminum alloy. Its main function is to close the cylinder and install the valve and piston. At the same time, it also has to withstand the high temperature and high pressure inside the cylinder, which has the functions of protecting the valve and piston, stabilizing the cylinder temperature, reducing noise and so on.

Casting and molding: engine body, cylinder head, clutch shell, drive rear axle. Forged type: crankshaft, semishaft, camshaft, connecting rod, valve top rod.The difference between hub forging and casting is that the production and processing methods are different.

Therefore, it is obviously illogical to say that EA888 uses cast iron to reduce costs. Secondly, EA888 is not entirely cast iron, the cylinder head is aluminum, and the cylinder block is cast iron. If the cost is controlled, it should be all cast iron. Why is the cylinder head is made of aluminum, and the cylinder block is cast iron. In short, Volkswagen EA888 series The motivation to use a cast iron engine is not because it is lowered.

The engine is composed of two major parts, the cylinder block and the cylinder head, which are connected to each other by bolts. Alloy cast iron is commonly used as engine cylinder block materials, but cast iron has many innate shortcomings, such as heavy weight, poor heat dissipation, high friction coefficient, etc. Therefore, more and more engine cylinder blocks are made of aluminum alloy.

Most pickup trucks will use diesel engines, because diesel engines have stronger torque and higher fuel economy. However, some pickup trucks use gasoline engines. The engine adopts in-cylinder direct injection technology, aluminum alloy cylinder head and cast iron cylinder block.

Automotive cylinder head deformation treatment method

1. The deformation of the car cylinder head can be repaired by grinding, but the thickness of the cylinder head becomes thinner each time it is polished, the volume of the combustion chamber becomes smaller, and the compression ratio increases, thus causing the engine to explode. Or replace the new engine cylinder head directly. The deformation of the cylinder head will cause problems such as burning oil, decreased power, and increased fuel consumption.

2. The deformation of the engine cylinder block can be repaired by grinding method, but the thickness of the cylinder head becomes thinner each time the grinding, the volume of the combustion chamber becomes smaller, and the compression ratio increases, thus causing the explosion of the engine. It is best to contact the after-sales service for maintenance. Grinding should not exceed a certain thickness. For example, the height limit value of the cylinder head of the Santana engine is 1360mm.

3. Replace the rubber seal on the cylinder pad, and then install the cylinder pad. At the same time, the cylinder head bolt is strengthened by cooling and then hot tightening.

4. The general method is: 1 The bulge near the screw hole of the plane of the cylinder block can be flattened with oil stone or flattened with a fine sel. 2 The unevenness of the cylinder block and the cast iron cylinder head can be repaired by milling and grinding. It can also be flattened with a shovel or applied with abrasive paste, and the cylinder head can be placed on the cylinder block to grind.

What is the reason for the failure of the cylinder head of the automobile

The reason for the failure of the cylinder head of the automobile is when the alloy cylinder head encounters high temperature; when the tightening torque of the cylinder head bolts is uneven; when the cylinder pad is eroded in a large area; other external forces It will cause damage to the cylinder head. The cylinder head of the car needs to be repaired or replaced in time. The problem of broken cylinder head is as follows: I often feel that the engine is weak and it is difficult to speed up while driving.

The reasons for the fracture of the automobile cylinder head include: the alloy cylinder head encounters high temperature, the uneven tightening torque of the cylinder head bolts, the large area of the cylinder cushion, and other external forces. Therefore, we need to repair or replace the cylinder head of the car in time to ensure the normal operation of the engine.

The reasons for the failure of the car cylinder pad are: the engine is caused by overheating, such as lack of water and dry burning, electronic fan failure or water tank blockage, etc., causing the coolant to boil. The cylinder cushion is of poor quality and uneven in thickness; there is an airbag in the mouth of the bag, and the asbestos is unevenly laid or the edge of the bag is not tight.

The main faults and causes of the cylinder head are: after the connecting rod bolt is loosened, it also causes the piston inertia to hit the cylinder head. Qualified bolts should be selected and tightened as required. It is forbidden to use old bolts.

Common damage to the cylinder head: deformation.The warping deformation of the bottom plane of the cylinder head is often caused by improper disassembly and installation, which will cause the cylinder to be loosely sealed and produce air leakage and water leakage. 1 The warping deformation of the junction plane of the cylinder head can be measured with a straight ruler and a thickness gauge. 1 Crack.

This will shift the gap in the most deformed part to the free end before and after the cylinder, and finally the gap will gradually disappear. If it is tightened from both sides to the middle, the gap will be concentrated in the middle, and the cylinder junction will form a bow-shaped gap, causing steam leakage.

What circumstances need to change the cylinder head

If the cylinder head is seriously deformed, it needs to be replaced. If the cylinder head is deformed, it will cause problems with the sealing of the engine, which will lead to air and oil leakage in the engine.If there is a crack in the cylinder head, it also needs to be replaced. Cracks in the cylinder head will also cause air and oil leakage in the engine.

If the cylinder head is seriously deformed, it needs to be replaced. If the cylinder head is deformed, it will cause engine sealing problems, which will lead to air leakage and oil. If the cylinder head is cracked, it should also be replaced. Cracks in the cylinder head will also cause engine air leakage and oil.

If the cylinder head is seriously deformed, it needs to be replaced. If the cylinder head is deformed, it will affect the sealing of the engine, which in turn will affect the leakage of the engine. If the cylinder head is cracked, it should also be replaced. Cracks in the cylinder head will also affect the air leakage and oil leakage of the engine.