What is the bearing?
A bearing, which is called a bearing in English, is a piece that allows the movement of two metal pieces on top of each other. The bearing is a thin metal sheet in the shape of a semicircle, which is placed between the crank and the connecting rod so that these parts can work together smoothly and without problems. To better understand the operation of the bearing, it is better to learn more about the way the car engine works. In the engine, the reciprocating movement of the pistons must be converted into a rotational movement by the crank so that this power can be transferred to the gearbox to allow the car to move; Therefore, the crankshaft must be connected to the pistons, which is done through connecting rods; But the movement of the crankshaft inside the connecting rods creates a lot of friction, and this is where the bearing comes into play.
In fact, if there is no bearing, friction will prevent these two parts from moving together, and this can cause a lot of damage to the engine. The car engine bearing, which has a metal body and is resistant to heat and shock, consists of two semicircular rings, which, by being placed between the connecting rod and the crankshaft, cause their smooth and frictionless movement. It may be interesting to know that bearings are also considered a subcategory of bearings and they use balls to reduce the friction of parts. This category of bearings is divided into two types of bearings and roller bearings based on the type and shape of the balls. If the balls are spherical, the bearing is a ball bearing, and if the balls are conical or cylindrical, it will be a roller bearing.
✔️ The bearing tasks in the car engine
Now that we are familiar with the bearing, we can easily learn about the tasks it carries out in the car engine. According to the things that have been stated, the duties of the bearing include smoothing the movement of the crankshaft and connecting rod, reducing the friction between the crankshaft and connecting rod and preventing damage and corrosion of these important parts, preventing the crankshaft and piston from colliding and damaging them, preventing vibration and noise. The mechanical parts will hold the parts together tightly.
✔️ Types of bearing
The bearings in the car engine are divided into two categories, fixed and movable, based on the type of operation and location. These two types of bearings are connected to the fixed and moving axes of the crankshaft, respectively. The fixed or main axis of the crankshaft is connected to the cylinder block and rotates around its axis, but the movable axis is connected to the connecting rod and rotates around the main or fixed axis. Whether the bearings are fixed or movable, they are made up of two semicircles that are screwed together. Also, both types of bearings are thicker than the crankshaft, and the gap between them is filled with oil. This oil covers the crankshaft in a very thin layer and while keeping it suspended inside the bearing, it helps the crankshaft to move smoothly.
✔️ Fixed bearings
Fixed bearings actually play the role of supporting the crankshaft and by connecting around the fixed axis of the crankshaft, they adjust its slack relative to the piston and cylinder block. . Since the crank has a tendency to move back and forth when it rotates, the fixed bearing controls this tendency, which is the slack of the crank, and prevents possible impacts to it. In this type of bearing, which is also called crank bearing, one of the two half circles of the bearing is connected to the cylinder block on one side, and the other half circle is bolted to it after winding around the crankshaft axis. In four-cylinder engines, which are the most common examples used in the automotive industry, five fixed bearings hold the crankshaft. These bearings are installed with holes so that oil and lubricants can reach the crankshaft through these holes and make the rotational movement of the crankshaft easier. Grooves are installed between these holes so that the oil can flow through them like a stream
✔️ Moving bearing
Moving bearings are placed between the connecting rod and the crankshaft. These bearings adjust the slack of the connecting rod relative to the crankshaft and prevent possible impacts between the two. These bearings, known as connecting rod bearings, are very similar in structure to crankshaft bearings, except that the crankshaft is free and converts the reciprocating motion of the piston into rotary motion. One of the semicircles of the movable bearing is connected to the connecting rod, and the other is bolted to it after winding around the crankshaft axis. These bearings are only grooved and there is no hole in them.
✔️ Slipping bearings
In this type of bearing, different layers of materials are placed on top of each other and create a protective housing. These bearings are usually used as holders and protectors of movements.
✔️ Roller bearing
This type of bearing consists of two rings and a number of balls between them. The balls are tangent to each other but brass nets are used to separate them. The distance between the two rings and the diameter of the balls are the same in all parts of the rolling bearing. This type of bearing is mostly used for moving bearings.
What does the bearings mean?
According to the things that have been stated, we understand that the bearing plays a very important role in the car engine because it prevents friction between the moving and rotating metal parts and makes their movement easier. And it makes it faster. The term bearing failure also refers to any defect in the functioning of this vital part. In simpler terms, a bearing in a car engine keeps the crankshaft rolling in a layer of oil and prevents it from wearing to other surfaces while allowing for smoother rotational movement. Now, if for any reason this layer of oil is not formed between the bearing and the crankshaft, wear and friction between the metals will occur, and this will cause the layers of the bearing to wear out by raising the temperature, and then may lead to their melting. . This defect, which causes severe damage to parts such as the crankshaft, is called bearing damage.
Generally, bearing knock occurs when the bearings are either too far from the crankshaft or too tight. If the bearing sticks to the crankshaft, the engine will run rough and heavy, causing it to fail. On the other hand, if the bearing deviates from its standard state due to wear and tear and loses its thickness, it will move away from the crankshaft, in which case the crankshaft will vibrate. If this happens, a sound like a knocking or sloshing is heard from the engine; Therefore, if you hear an unusual sound from the car engine, turn it off quickly to prevent further damage.
What are the reasons for bearing?
The main reason for the engine bearing to knock is the lack of oil or a problem in its lubrication, but in addition, since the bearing is one of the consumable parts of the car engine and is subject to depreciation, it will wear out over time and must be replaced. to be With this explanation, we will explain the reasons for the bearing. Not changing the oil on time Considering the above, the effect of not changing the engine oil on time will be quite clear. Engine oil is the most important material for the proper functioning of the bearing, and failure to replace it at the appointed time will result in dirt and reduce the lubrication ability of the oil, which in this case will interfere with the proper functioning of the bearings. Using low-quality or fake oil Using low-quality and fake oil, which unfortunately has become very common these days and has made it difficult to find high-quality oil, can cause serious damage to the bearings because low-quality oils lack sufficient lubrication and will not provide proper lubrication. Dirty oil filter If the oil filter is not replaced on time, a lot of deposits will accumulate in it and it will lose its properties. In this case, deposits enter the oil and can interfere with the operation of the oil pump. As a result, the oil pump cannot properly pump oil to the bearings. Oil pump failure The oil pump, like all the technical parts of the car, may break down after some time of use. If this happens, the oil will not reach the engine and bearings and it can cause serious damage. Mixing water and oil If the cylinder head gasket malfunctions and the cooling water leaks into the engine, it is said that the engine has mixed water and oil. In this case, the oil that is mixed with water loses its lubrication properties and as a result damages the bearings. Overheating of the engine In addition to a malfunction in engine lubrication for any reason, an abnormal rise in engine temperature can also cause bearings to knock. The engine temperature may rise due to various reasons such as radiator failure, cooling fan failure, reduction in engine water level, or thermostat locking, which will result in increased friction of the parts. Driving with high engine speed Constantly driving at high revs and revving the engine to redline can damage the bearings as the engine heats up and creates severe friction. Also, the excessive speed of the motor may be beyond the capacity of the bearing. Wear of bearings As mentioned, bearings are consumable parts and must be replaced at certain intervals; Therefore, if the life of the bearings is long, they may not be able to do their job properly due to erosion, which will lead to the possibility of the bearing breaking.
✔️ Symptoms of bearings
Bearings have certain signs that if seen, the engine should be turned off quickly and the car should be towed to the repair shop to prevent further damage. be prevented The first sign of bearing damage is a clicking sound when you press the gas pedal or accelerate, so as the engine speed increases, the sound of two metal pieces hitting each other will be heard completely. The next one is engine locking due to excessive friction between parts. In this case, the engine will not start at all; And finally, one of the reasons for turning on the car check light or flashing it can also be the bearing.