Signs of a faulty clutch release bearing. Clutch Release Bearing: Symptoms and Causes of Breakage

Clutch breakage is one of the troubles that can lie in wait for the driver on the road. Usually, the car simply stops moving, while the motor is working normally. Such a breakdown does not always occur suddenly, often before this one can observe some signs of an imminent breakdown.

Clutch failure symptoms

In general, the main signs of a clutch malfunction are clutch slippage and incomplete disengagement.

In case of incomplete disengagement (pedal pressed), there is a difficult shift in gears when the engine is running, noise and crackling when shifting gears, a large free travel of the clutch pedal. When the clutch “slips” (the pedal is released), you can smell a burning smell in the cabin from burning clutch disc linings, the dynamics of the car will deteriorate, the engine may overheat,.

It is good if the driver notices such signs of a clutch malfunction in time, in which case you can get to the car service even without assistance, you just need to drive slowly, do not accelerate and carefully change gears, preferably using the so-called "double clutch release" and "overrun" when switching ...

At the same time, to switch to the highest gear, the clutch pedal is depressed, the gearshift lever is held in neutral position, the clutch pedal is released, then pressed again, after which the corresponding gear is engaged.

To switch from high to low gear, the gearshift lever is also delayed in neutral, the clutch pedal is released and the gas pedal is pressed slightly, after which the clutch is again squeezed out and the desired gear is engaged. Having mastered such a gear change, you can not only reduce the load on the clutch parts, but also significantly extend the "life" of the gearbox.

Causes and main clutch malfunctions

The most common cause of clutch failure is improper use of the vehicle. For example, if the car “sat down” in the snow, and you continue to accelerate the acceleration, or you really like to start with slipping, all this will reduce the service life of the clutch.

In addition to the clutch disc itself, the release bearing can also "fly" - it serves to smoothly engage and disengage the clutch. Usually, before the release bearing "dies", you can hear a characteristic squeal - this is a sure sign that the bearing needs to be replaced.

In principle, in the event of a sudden breakdown of the release bearing, you can continue to move, however, you will not be able to use the clutch, because it will be constantly on. For this reason, you will have to get under way either from the tug, or by turning on the starter and first gear (in this case, the car will immediately start moving and then start), of course, if you have enough "strength".

As soon as the car starts and picks up speed in first gear, release the throttle, immediately engage second gear, and in the same way change to third. When switching, the main thing is to catch the right moment when the speed of rotation of the gearbox shaft and the motor coincide, otherwise a crunch will be heard when switching.

Of course, you need to resort to this method only as a last resort and if there is no way to deliver the car to the service in another, more gentle way for it.

By the way, when replacing the release bearing, the service station may advise you to replace the clutch disc as well. In fact, this does not always need to be done if the clutch disc is in good condition.

The reason for the failure of the clutch may also be a breakdown in the mechanism of its drive, for example, a breakage or jamming of the clutch drive cable, breakdown of the lever system, leakage from the hydraulic drive, if the clutch is hydraulic, or other similar breakdowns in the drive.

Video: clutch breakdown, how to get to a car service or home on your own (this is sometimes possible).

As you can see, it is possible to continue driving in some cases even if the clutch is faulty. All of these recommendations will come in handy for owners of a car with a manual transmission. Good luck!

Regular use of the car sooner or later leads to operational failures of its individual systems, which are often caused by malfunctions of the engine, chassis or any other mechanism. Problems with the clutch also cannot be ignored by the car owner, because the appearance of even the slightest failures in the operation of this unit is already "felt".

In order to detect the problem as early as possible, you should regularly conduct a visual inspection of all elements of the car clutch, and of course, do not forget to listen to the operation of the car. In this article, we will tell you what you should pay attention to in the first place and how to independently deal with the emerging problems of the clutch system.

1. What is clutch?

The automotive clutch can be called a "torque switch", the main purpose of which is to smoothly connect the engine flywheel to the gearbox input shaft at the moment of movement and when shifting gears. Moreover, the clutch has one very important function: in situations of heavy braking, it protects the transmission from mechanical overload and, as a result, from costly repairs.

Today, there are several types of clutch. So, for example, given the number of driven discs, all such mechanisms are divided into two groups: single-disc and multi-disc, with the most common option being a single-disc clutch.

Based on the working environment of the clutch, two types of it can be distinguished: "dry" and "wet". Nowadays, the "dry" clutch is especially popular among automakers, for the operation of which, unlike the "wet" type, does not require a special oil bath.

By driving the mechanism, the clutch can be hydraulic, mechanical, electrical or combined, and from the point of view of design features, it differs in the way of pressing the pressure plate and can have a circular arrangement of springs or have a central diaphragm.

The constituent elements of the clutch system are: the clutch disc itself (it is called "driven"), the pressure disc, the release bearing and its drive fork, the drive system and the clutch switch (release pedal).

As for the principle of operation of an automobile clutch, in a single-disc version it is reduced to tight compression of the working surfaces of the flywheel, disc lining and the clamping surface of the "basket". In the process of work, when the release springs act on the pressure plate of the "basket", it is forced to fit snugly against the clutch disc, which presses the latter against the flywheel.

Since the input shaft fits into the splined clutch, the torque from the clutch disc is transferred to it. When the driver presses down on the pedal, the drive system comes into play and the release bearing applies pressure to the release springs, pushing the working surface of the basket away from the disc. The disc "becomes free", and the input shaft of the gearbox stops rotating, despite the fact that power unit and does not think to stop.

In cars equipped with a two-disc clutch, there are already two discs and a "basket" with two working surfaces. Between them there are restrictive bushings and a system that regulates synchronous pressing, and the process of disconnecting the flywheel and the input shaft is the same as in a single-plate clutch.

In automatic transmissions, a wet multi-plate clutch is most often installed, although sometimes automatic gearboxes with a dry clutch are found. In such devices, clutch release occurs not by pressing the corresponding pedal (since it simply does not exist), but by means of a servo drive, which is also known as an actuator. It should be noted that gear shifting is also performed using these mechanisms. There are several options for actuators: electric, presented in the form of a stepper motor, and hydraulic, in the form of a hydraulic cylinder. The process of controlling the servo drives is carried out by means of an electronic unit (for electrical devices) and a hydraulic valve (for hydraulic models).

Gearboxes of a robotic type have two clutches working alternately: when the first clutch is pressed to change a gear (for example, the first one), the second one awaits the command to change the next gear.

2. Signs of a faulty clutch

When the clutch malfunctions, this also affects the nature of the movement. vehicle that cannot go unnoticed. So, the most common signs of clutch malfunctions are its incomplete shutdown (they say the clutch "leads"); incomplete engagement (clutch "slips"); working jerks; the appearance of vibration when the clutch is turned on or noise when it is turned off.

Incomplete disengagement entails problematic engagement of gears while the engine is running, as well as noise, crackling, rattling and other similar sounds accompanying gear shifting. In addition, the free play of the clutch pedal is significantly increased.

"Slip" of the clutch is characterized by an unpleasant smell of burned friction linings of the driven disc, general overheating of the power unit, increased fuel consumption, and insufficient vehicle dynamics. Each of the above indicators has its own cause, which can be easily detected during a more detailed diagnosis.

3. The most common causes of clutch malfunctions

As a rule, the main reason for clutch failure lies in the improper operation of the vehicle. For example, if the car is stuck in a snowdrift, and you continue to accelerate hard, trying to free yourself, or you just like to start with a slip, keep in mind - all this significantly reduces the resource of the clutch unit.

In addition to the clutch disc itself, the release bearing can also fail, which serves to smoothly engage / disengage the clutch. Often, before the "death" of a given part, the driver can hear a characteristic squeal, indicating that the bearing should be urgently replaced.

The reasons for the working failure of the clutch can also be malfunctions in the mechanism of its drive, presented in the form of a break or jamming of the cable, breakdown of the lever system, fluid leakage from the hydraulic drive (if you have a hydraulic clutch) or other similar malfunctions. Let's look at the possible causes in more detail, defining their relationship to a specific symptom.

Incomplete disengagement of the clutch, when it "leads", does not engage at all or hard to engage the forward gears, and engaging the gear reverse accompanied by a bang, may be the result of the following reasons:

1) The gap is incorrectly set;

2) The driven disc is damaged or deformed;

3) Diaphragm spring worn out;

4) Broken, jammed or damaged cable (or linkage);

5) In the case of a hydraulic system, fluid leakage is possible;

6) The piston cuff located in the working cylinder is damaged;

7) There is a small pedal travel;

8) The bearing guide sleeve needs additional lubrication;

9) Periodically, the hub of the driven disk, located on the splines of the input shaft, jumps;

10) The pressure plate levers are adjusted differently.

Incomplete engagement of the clutch (the car "slips", the smell of burnt friction linings is clearly felt, slow acceleration is noticeable, loss of speed and slow climbing), as a rule, is observed in the following cases:

1) The clutch disc is not running in;

2) Diaphragm spring is loose or damaged;

3) The mating surface of the flywheel is worn out;

4) The clutch cable is seized;

5) Weakened pressure springs;

6) The friction linings of the driven disc are oiled;

7) The elements of the assembly are excessively worn out;

8) Blockage or blockage of the expansion hole of the master cylinder caused by swelling of the cuff.

If vibration is observed when the clutch is engaged, then most likely:

- the engine and gearbox are loose;

The splines located on the input shaft of the gearbox are worn out;

Worn pressure plate, flywheel or diaphragm spring;

The clutch pads warped;

The rivets of the linings are loose;

The hub of the driven disc is seized on the splines of the input shaft or the plastic springs of the driven disc have lost their elasticity.

Also, the vibration can be caused by uneven adjustment of the pressure plate levers. Vibrations and noises coming from the transmission are often the result of improper pedal free travel; damage to the driven disc or fatigue of its springs; breakage or severe wear of the elements of the damper device of the specified disc.

The main reasons for the characteristic increase in noise when disengaging the clutch are wear or any other defect in the release bearing; damage to the pins of its diaphragm, or severe "fatigue" of the front bearing of the input shaft of the gearbox.

An increased noise level when the clutch is engaged is due to the failure of the damper springs or a decrease in their elasticity, a decrease in the elasticity of the release spring of the clutch release fork (or its jumping off) or breakage of the plates that connect the pressure plate to the casing.

If, when the ignition is turned off, the clutch pedal remains pressed to the floor, it means that the drive or release bearing is seized, and a squeak when the clutch pedal is pressed in a situation of an inoperative engine indicates a lack of lubrication or wear of the pedal axle sleeve.

It happens that the clutch can be disengaged only when the pedal is pressed sharply, and the smooth action easily brings it to the very stop on the floor, without turning on the clutch. There may be several reasons for this:

1) The master cylinder mirrors are worn out or heavily soiled;

2) Significant wear of the master cylinder piston cuff is observed;

3) Low level fluid in the reservoir of the clutch master cylinder;

4) The connection of the pipeline with the main and working cylinders is not tight enough, as a result of which fluid leakage is observed.

When there are jerks in the clutch operation, then the reason should be sought in the jamming of the driven disc hub, oiling of its friction linings (or contamination of the flywheel and pressure plate), seizure of the clutch release drive mechanism, as well as increased wear of the friction linings or loosening of their rivets.

4. Self-diagnosis of clutch faults

When the car accelerates or, conversely, slows down, in order to shift the gears of the gearbox, the crankshaft has to disengage each time and again come into contact with the power train of the car. Since this happens very often, over time, signs of clutch wear begin to appear in the behavior of the vehicle during its movement on the road.

As we have already found out earlier, all clutch faults can be divided into several groups, among which the most frequent are faults associated with incomplete engagement of the clutch (when they say that it is "driving") and with full engagement (the clutch "slips").

Experienced car owners know how to check the clutch for partial disengagement. In principle, there is nothing complicated about this, and if at low revs, with the pedal pressed all the way, the first gear is easily turned on, without jamming and extraneous noise, it means that the shutdown occurs completely. Gear noise and difficult engagement indicate that the clutch is "driving".

If in the process of movement you start to hear the smell of burning, and on the rise the car slows down noticeably, and in general it starts to pick up speed badly, then even diagnostics are not needed, since the slipping is "evident". This means that when the clutch is disengaged, the drive and driven discs do not close tightly enough.

The simplest (but rather reliable) method of self-diagnosis of the clutch on cars with a manual manual transmission involves the following actions:

First, you need to warm up the engine so that the thickened oil does not provide additional resistance; then you need to put the car on the parking brake (preferably on level ground, without serious slopes); further, using the gas pedal, the engine speed should be brought to a value of 1500-1700. Now we squeeze the clutch pedal all the way and "hammer" the first gear, after which the pedal is smoothly released.

If, after you have completely removed your foot from the clutch pedal, the car engine does not stall, or stalls only after a while, this means that the clutch definitely requires repair.

5. What to do with a faulty clutch?

If a breakdown occurs, you should find out about it as soon as possible, which will help prevent more serious consequences by timely elimination of malfunctions, preferably as soon as possible.

If the clutch fails, one of the possible reasons this phenomenon may be a faulty driven disk. Removing and inspecting the clutch for damage, deformation or defects will help to eliminate such a problem and repair the clutch. If any, the damaged part should be replaced with a new one.

If the problem lies in a leak in the clutch hydraulic system, first check all pipes, as well as the master and slave cylinders. In addition, air trapped in the clutch hydraulic system is often the source of the problem, and if this is the case, then all that is needed is to simply remove it.

Note! Before disassembling the power unit and checking the clutch mechanism for wear on its constituent parts, make sure there is sufficient free pedal travel. To do this, using a ruler, measure the free travel of the pedal stop that reaches the center of the driver's foot stop (for example, for some models of the most common domestic VAZs, the free travel should be from 20 to 30 millimeters).

If you do not know exactly what the specified distance should be specifically for your car, then this point can be clarified either in the vehicle's service book or on the website of its manufacturer.

After you make sure that the free play is normal, it is advisable to contact the specialists of the nearest station Maintenance, since with a lack of experience in terms of disassembling and adjusting the clutch, there is a serious likelihood of harm to it. In case of self-repair (if you still decide to take a chance), you need to carefully disassemble the clutch basket and carefully examine all the discs, paying special attention to the degree of wear of the parts, the condition of the springs and the presence of oil. The release bearing should be inspected in a separate order, because many problems are associated with it.

The clutch assembly is one of the most important devices in a car. Thanks to the clutch, there is a safe, smooth disconnection and connection of torque from the engine to the gearbox. In the clutch system mechanical boxes gear shifting (manual transmission), one of the main roles is played by the release bearing (VM), which will actually be discussed in this article.

How does a clutch release bearing work?

There are two types of release bearings - mechanical and hydraulic. The first, as the name implies, is driven by mechanical action thanks to special rods and cables. The hydraulic type works under the direction of hydraulics, which takes over the power loads, making it easier for the driver to use this unit.

The release bearing design is quite simple at first glance, and at the same time it is very effective. The BM consists of a bearing, as you might have guessed from the name and the coupling on which it is pressed. The clutch release bearing is located on the input shaft of the gearbox, or rather on its flange. Depending on the clutch pedal, the bearing moves along this shaft.

It works as follows. When you press the clutch pedal using rods or cables, or hydraulically in the case of hydraulic systems, the clutch force is transmitted to the clutch fork. This fork actually moves the release bearing along the flange. The release bearing, in turn, acts on the clutch basket petals, as a result of which the friction discs are disengaged. It is at this moment that a particular gear is switched.

When the previously depressed pedal is released, the BM returns to its original position, as well as the diaphragm spring blades. No pressure is applied, so the flywheel, pressure and slave are connected, as a result, the clutch is engaged.

Why is the release bearing failing?

VM malfunction occurs for several reasons. Firstly , due to the fact that some drivers abuse the clutch and, squeezing it for a long time, do not release the pedal (keep your foot on the pedal), thereby subjecting the release bearing to heavy loads. This small part is not designed for sustained loads, as the challenge is to quickly change gears while getting a minimum load. But if the clutch is squeezed out for a long time and this happens regularly, the resource of the part is significantly reduced.

Secondly , wear of the release bearing occurs as a result of natural wear after the resource of the part is exhausted, as a rule, it is -100-150 thousand km. mileage. In case of non-observance of the rules of operation, the clutch release may fail much earlier.

Thirdly , wear is influenced by external factors such as dust, dirt, moisture, as well as temperature and mechanical stress. The release bearing itself is inexpensive, but the trouble with VM breakdown is that if you don't notice its failure in time, you can imperceptibly "ditch" the entire clutch unit. The result is a complete clutch replacement, which is many times more expensive than a conventional release bearing replacement.

Symptoms of a malfunctioning clutch release bearing

• When pressing the clutch pedal, extraneous sounds (whistling, hum, etc.) are heard.
• Difficulty shifting gears.
• Vibrations or even knocking may occur.

Replacing the release bearing

Let's summarize

The release bearing, like most other components, suffers from non-compliance with the rules of operation, as well as the habit of driving with the clutch depressed. At the first sign of a release bearing malfunction, take action, otherwise you will have to change the entire clutch assembly, and this costs much more ...

I have everything, thank you for reading to the end, write in the comments about how long after you change the release bearing and by what signs you determine its malfunction. If you like the article, share it with your friends on social networks using the special buttons below. Good luck, take care of yourself!

The clutch is a very important component in the design of any car. It includes the Signs of a malfunction of the element, its purpose is further in our article.

What is it for

Release bearing including) provides a connection between making them disconnected and connected for a certain period of time. It is controlled by pressing the pedal.

The principle of operation of this element is very simple and is as follows. When the driver presses the clutch pedal, the fork is activated and acts on the slave cylinder. He, in turn, produces a force aimed at disconnecting the pressure and driven disc. The clutch release bearing is engaged to bring the two elements back into contact. Symptoms of malfunction (VAZ-2114 including) of this element occur due to the high loads placed on the part. This element constantly meshes with other components such as the flywheel and clutch disc.

Where is used

Automakers use this element on dual-drive systems - a slave and a master. The first element receives torque from the second and transfers it to the transmission. Further, through the cardan transmission, the force is transmitted to the gearbox, and then to the wheels. The drive disc is firmly attached to the crankshaft. To switch the driver from one gear to another (it does not matter whether it is high or low), it is necessary to separate these two elements. This operation is performed precisely thanks to the bearing. The effort is controlled by pressing the clutch pedal. When it is pushed "to the floor", the transmission of torque is stopped - the bearing rotates at the same speed as the flywheel. As they are released, the two discs are connected to each other. During this time, there are high loads placed on the clutch release bearing. Malfunctions of these elements occur precisely because of the heavy loads.

It is worth noting that while driving, when the car is driving "in gear", this element remains in a calm state. But as soon as you need to switch to the next or previous speed, he immediately connects to work. Despite its small size, this element performs a responsible function. In case of any malfunction, further operation of the car will be impossible or difficult. Therefore, at the first symptoms, you should pay attention to it. What are the signs of malfunction in the release bearing of the clutch ("Kalina" including), we will consider further.

How to determine wear and tear?

First of all, the element will begin to emit characteristic noises and sounds. Moreover, what is most interesting is that it is impossible to notice them while driving in gear. But as soon as you press the clutch pedal, there is a terrible hum, and sometimes a knock. It especially intensifies in winter. It is worth noting the high reliability of the design of such a part as the clutch release bearing. It is very difficult to notice the signs of a malfunction of this unit in the early stages. Sometimes a slight rustling will be heard, which does not increase at all over time. However, this symptom is quite enough to diagnose the element for a malfunction. Difficulties also arise when shifting gears, especially the reverse. The inclusion of speed can be accompanied by a characteristic crunch. Also, this symptom may indicate a malfunction of the synchronizers or the pressure and driven disc. But in any case, when noise appears, it is necessary to diagnose all components of the unit.

It should be noted that the bearing is made of strong steel with a low expansion coefficient. However, the glass itself is very sensitive to temperature extremes. Its deformation can provoke a knock when the pedal is depressed. In this case, it is necessary to urgently replace the clutch release bearing.

Symptoms of malfunction may be accompanied by inability to turn off the transmission. Both discs will be in constant mesh. A similar symptom occurs due to breakdown and fluid leakage to the clutch. The pedal becomes ineffective. Operation of a car with such a breakdown entails increased wear of synchronizers and transmission gears.

How to extend the resource?

As we said earlier, the task of this bearing is to separate the two discs.

Since it is practically not used when driving in gear, the main load is assigned when the pedal is depressed. If you hold it for a long time, the bearing will wear out a lot.

But what can be done?

Everything is very simple. For example, you come to an intersection with a red traffic light. If within 5-10 seconds the green does not light up, feel free to turn on the "neutral", and keep the car (if it is a slope) on the handbrake or the brake pedal. Fortunately, many traffic lights have a timer, so you can predict the situation in advance. But this rule should be used not only at intersections, but also in any other traffic situation (for example, standing in a traffic jam). You should not "play" with the clutch, sneaking behind an oncoming vehicle in order to maintain a minimum distance.

The less time you keep the pedal depressed, the better for the bearing. Do not be too lazy to once again transfer the gearbox selector to "neutral" - so you can avoid if not expensive, but rather time-consuming repairs. Since replacing the bearing involves removing the transmission and clutch basket. And if this is also a driveshaft.

Conclusion

So, we found out what signs of a malfunction have a clutch release bearing. As you can see, the main symptom is extraneous sounds in the area of ​​the gearbox and clutch, as well as difficulties when changing gears. By the way, this element is checked simply - it is enough to grasp its base with one hand, and rotate it along the axis with the other. If you are replacing a disk or basket, do not be too lazy to make such a diagnosis. After all, after a couple of hundred kilometers, you will have to remove all attachments again or go to the service, where they will ask you for a considerable amount.

Today, the most common clutch systems are with two discs - a master, rigidly coupled with and a slave, transmitting torque to the checkpoint. To change gears or transfer the car to a disconnection of the clutch discs is required, which is carried out using a release bearing that pulls the driven disc away from the drive.

Release bearing location

It is an important element of the clutch system, and at the same time one of the most vulnerable parts. Clutch release bearing in the process of movement of the car is at rest, engaging in work only when changing gears. The breakdown of such a small part guarantees the impossibility of further operation of the car, so you need to change the bearing immediately when it appears clear signs its malfunction.

The part costs from 300 to 1500 rubles or more, depending on the manufacturer and car model. Replacing a bearing at a service station will cost 3000-7000 rubles, so if you have the desire, opportunity and a normal set of auto tools, it makes sense to do it yourself and save a lot.

Release bearing types

Two types of release bearings are now common:

• roller or ball- mechanical units transmitting force to the bearing through a rigid linkage of rods;
• hydraulic- here the force is created by hydraulics, making the clutch pedal much easier to depress.

Hydraulic release bearing

Roller release bearing

Operating principle

The purpose of the release bearing is to ensure the connection and disconnection of the clutch when the pedal is depressed in the passenger compartment. The principle of the part is quite simple:

• the driven disc is pressed against the flywheel by the pressure disc, due to which the clutch is provided;
• pressure on the pressure plate is provided by a diaphragm spring, on the inner petals of which the clutch release bearing acts;
• the movement of the bearing, initiating the separation of the discs, is provided by the clutch fork.

Release bearing in the vehicle clutch system

Reasons and signs of release bearing breakage

The reason for the breakdown of this part is uneven loads on it at the moment when the clutch is depressed, and it goes back together with the driven disc. For this reason, it is strongly discouraged to hold the clutch pedal in gear for a long time. In principle, this is a reliable and durable part, and it breaks down most often in novice motorists.

The most important symptom of bearing wear is when depressing the clutch pedal... If the sound appeared in the summer, this is almost a guarantee of future problems, but if it came along with frost, there may be an elementary change in the linear dimensions of the bearing glass due to the temperature drop outside. The release bearing in most cars has an undeniable advantage - high strength, so even when noise appears, you can afford to do nothing for a while, but watch whether it is getting stronger.

How to check the release bearing

Checking the clutch release bearing is carried out by ear when depressing the pedal, when it is in operation (rotates). Depending on the stage and nature of the wear (a small amount of lubricant or production has started), the sound will be different, it can just hum or make noise or make other unpleasant sounds in the area of ​​the box. But do not confuse these sounds with those that can occur when the clutch pedal is not even depressed, since such a sign will indicate the bearing of the input shaft.

Replacing the clutch release bearing

If the bearing still needs to be replaced, the following sequence of steps will have to be performed:

• dismantling of the checkpoint;
• disconnecting the ends of the spring clip from the clutch;
• removal from the bearing guide sleeve;
• detaching the spring holder;
• removing the bearing from the coupling and installing a new part.

The new bearing should rotate as easily as possible, even minimal tension and backlash are unacceptable.

Before installing the parts on the guide bush, their surfaces must be generously lubricated with grease.

In conclusion, it should be noted that the release bearings can without problems serve up to 150,000 kilometers, however, they often have to be changed every 50,000 km due to driver errors and bad roads that destroy the entire car, including the grip.