Slamming sound from a faulty siren: how to spot a breakdown?

Cars with front-wheel drive are very much loved by motorists all over the world. Often in the construction of such machines apply suspension systems such as "MacPherson". This is a very simple and reliable design that can work for many years without a single serious breakdown. But there are enough vulnerable units in front-wheel-drive cars. One of them is the hinge of equal angular velocities, and if it's simpler, it's just a CV joint, or a "grenade." The production of these parts uses the most modern and fairly solid alloys. The working part is treated by special spraying, the lubricant must ensure the details of the long work. But practice shows that there is nothing eternal. CV joints fail, even on new cars. How to diagnose the breakdown in this node, why the crunches of the joints, what are the consequences and how to change this important detail - let's try to figure it out.

How everything works

To begin with, there are two types of such hinges. These are internal, which work directly in the checkpoint, where the semiaxis is forced to move, as well as external ones - they can be found on the hubs. They transmit the torque to the wheels of the car.

Sometimes it seems that both internal and external hinges can work very long and fail in one day. However, this is not the way to think. As a rule, internal nodes can work very long, but external wear out more often. And then the machine makes a clapping sound from the faulty CV joint. Among the main reasons - the high loads that occur on the wheel hub in motion. Also among the reasons - a higher angle of rotation of the external product. These details are different and in appearance - the internal ones are much larger than the outer ones.

The structure consists of a cup body with grooves inside and a semiaxis from the outside. The inner casing resembles a spherical fist with grooves and a splined joint. Between the cup and the holder there are 6 balls.

Why crunches?

The structural element is very precise. The sleeve transmits force to the body and rotates it. The balls move in the grooves, and this allows you to change the angle between the semiaxes.

Over time, where the balls touch other elements, the surface is exposed to wear and tear. Some balls have a free stroke, as a result, the driver hears the characteristic sound of a faulty CV joint.

Since there are two nodes per wheel, it is sometimes very difficult to determine which one has worn out.

Typical causes of failure

Among the common causes are a marriage of production, which could not be identified before installation. Very often cases when new cars are equipped with counterfeit spare parts from low-quality metal.

Another common cause is a lack of lubrication. Due to the poor quality of the anthers (they tear), sand, water, dust from the road gets into the working parts.

Even more important is how the driver drives the car. With an aggressive manner of driving on domestic roads, the products fail very quickly. And there is that same terrible, clapping sound from a faulty CV joint - all car owners have heard it at least once. It is difficult to confuse something with something.

Whence this strange noise?

So. There are two such parts on each drive wheel. The internal transmit the energy of rotation from the differential to the axis, the outer ones from the axis to the hub. With the same design, these hinges have different sizes.

To independently diagnose where this nasty pop-up sound comes from the faulty CV joint, you can use one of two methods.

So, if the car is worthwhile, you can try to twist the axle on each part in turn. If everything is normal, you will not feel any backlash. If the joints are knocked, then there is wear and, moreover, quite large.

If you are on the move, it is very advisable to listen to the sounds that the car emits.

Symptoms of a faulty CV joint

It sounds when cornering, sharp acceleration, overcoming obstacles. However, if you hear this crunch more and more often when you move straight, then replacement is just necessary. It's just dangerous to drive on such a car.

More accurately, the failure will be indicated by barely noticeable jerks at the touch. A significant backlash is easily determined when the wheel is hung out. It is necessary to try to move it in different directions. Is there a backlash? SHRUS for replacement.

How do you know which SHRUS is faulty?

How to determine which SHRUS crunches? Unfortunately, the most accurate diagnosis can be difficult to put because the breakdown of the "grenade" is very similar to the malfunction of the ball, the steering tip and others. Therefore, once again check their condition.

To carry out diagnostic procedures with an external "grenade" is very simple. To do this, you just need to unscrew the steering wheel in any extreme position and start driving on the car. When there is a maximum angle between the semiaxes, you can clearly hear the clapping sound from the faulty CV joint. If you hear sounds when turning to the right side, you need to change the right one, if it crunches when turning to the left, then, respectively, the left one.

However, there are some features of the internal mechanism. They sometimes crunch and move straight. To test their performance, you can not even have any special skills in car diagnostics. It is enough to make a small trip to where there are no roads. You will hear sounds at the entrances to the pits.

But you can find out which of the mechanisms out of order is even more accurate. To do this, you need a lift. When the machine is suspended, the first gear must be engaged. Let the wheels rotate slowly enough. In this position, a crunch will be clearly heard. If you move the shaft, you can again feel the backlash.

If everything is as described, you are directly on the road to the store for a new mechanism.

Defective CV joint: consequences

How can they be? In the case of an external mechanism, the hub bearing can break . The inner can just fall apart somewhere. And then you have to either push or call the tow truck. You can not drive such a car.

But if it happened during the movement, the consequences can be completely different. Such a breakdown can cause a serious accident.

How to replace the mechanism?

You already know how to identify a faulty CV joint. But how to replace it? Some novice motorists sometimes even ask a question about the possibility of repairing this part. Many would like to avoid a replacement, because it costs money. But, alas.

Replacement is not anything complicated. Anyone can cope with this. To do this, you need a set of tools and a pit or a jack. If all mechanisms are replaced, it is better to perform the work in stages. First you need to do everything on one side, and only then can you move on to the other. But if there is a certain experience, you can change everything at once. It is worth saying that removing the second shaft can sometimes lead to a disruption in the installation of the semi-axle gears. To solve this problem, you have to visit SRT. Before removing the second shaft, insert into the gearbox the old case of the part already removed.

To replace the external assembly, the wheel must be dismantled. Then unscrew the hub nut, remove the brake caliper and the disc, the ball joint and the helmsman's tip. Pull the part outward for replacement only by knocking it out. For this you can use a hammer, but it is better to beat through a wooden spacer. Usually this operation does not take much time - the spline joints come out quickly enough.

To replace the old mechanism with a new one, you should put a new anther on the shaft and replace the old lock ring. Before installing a new CV joint, it is recommended to lubricate it abundantly. Mounting it on the shaft is carried out with the help of the same hammer. Next - the mechanism is installed in the hub, and then the suspension is assembled in the reverse order.

We change the inner SHRUS independently

This seems strange, but the internal mechanism changes much more easily than the outside. The entire replacement is also performed either on the pit or with a lift. This node is removed only from below.

At the first step, unscrew the bolts of the product. Now the part is held in the socket only by means of a flange. Turning the steering wheel into one of the extreme positions, you can achieve that the mechanism will drop out on its own. Well and further - all the same, as well as in a case with external SHRUS.

Different sets can be differently manned. Often in the configuration may be a different number of washers, lock rings, as well as other additional elements. Do not forget to install them, even if you did not find them in the previous kit. When purchasing spare parts, pay attention to the parameters.

Like most other auto elements, this mechanism requires a certain amount of attention. After all, the car is an expensive toy. Unplanned repairs of such a plan can cause serious damage to the budget. And these are only the smallest possible problems.

Always ensure that the vehicle is in good condition. This will save both your life and the lives of your loved ones.

So, we found out how to identify the faulty hinge of equal angular velocities and replace it with our own hands. We hope that the above information will be useful to you.