What to do if the banging of the grenade in the car – repair with your own hands
Despite the awareness of modern drivers (and such almost everyone has to become at the failure of his “iron horse”), almost no one has heard of a part called a CV joint. Well, those who have already got acquainted with it, probably have already spent quite a lot of money for its replacement or at best repair. In this article we will tell you about these so tricky and important automotive components, and also reveal the secret of their long trouble-free operation.
What is a C.V.
What is a C.V. in a car? Translated into “popular” language, it is denoted as a “grenade”. Consequently, if the car has such a spare part, sooner or later it will explode. Let’s leave jokes aside… Nevertheless, we shall not forget about the main thing. So, the CVR or “grenade” is a constant velocity joint. Exactly these spare parts serve for transferring of torque from the heart of a car (engine) to driving wheels. These parts not only enable the wheels “to start their work after the command “from above” – from the motor, but also completely control them.
Why the “grenade”? Firstly, this part is very similar to a real grenade, and secondly, its actions are really killer. If it fails, the vehicle will not be able to move independently until it is replaced or repaired.
C.C. Design
The C-shaft works practically the same way as the cardan known to all drivers. However, the drive of the latter is more advanced and complex. What are the differences? In the case of the cardan: the transmission is non-synchronous transfer of torque (that is, one shaft rotates evenly, while the other does not), and the crossing angle is quite difficult. C.V. differs in that it does all this work, but 90% easier: it has a great resource, since its rotation angles are no more than 70 degrees relative to the axis.
Important: CV joints originated more than a hundred years ago. Nevertheless, to date, they have evolved greatly and are one of the main components of absolutely all vehicles encountered on the road (regardless of their “age” or cost).
The grenade is a power part and is often subjected to stress. It therefore needs to be protected from the environment, which can be helped by lubrication (and thus prolong its life). The structure of the part is covered by a dust cover made of plastic or rubber (which is packed with grease and held on the shafts with clamps). It should be noted that the quality of the dust cover also determines the service life of the grenade. If this component will fail, and you do not take any action, you will soon have to check the CIA for serviceability (as it can not work in an unprotected environment and fails rather quickly due to the direct effects of the environment: ingress of dirt, road rainfall and other).
How to choose a C.V. joint
To date, there are several designs of this automotive component, among which the following should be highlighted as the most popular:
- tripod;
- reppa;
- knuckle (cam);
- ball ones;
- paired.
It is the ball type parts that are the most common in modern vehicles. Coupled and cam-type parts are most commonly used by special equipment, trucks, and tractors.
Signs of CV joint failure
The first sign is a knock, hum, rumbling (although the main sound is still a knock), from the side of the wheel, where the part, in general, is ready to “fly out”. By the way, these sounds are quite enough to determine the failure of the CV joint (even without any checks at the service stations).
It is worth remembering that a knocking grenade can be as a week, as well as several months. In any case, sooner or later it will fail … and then – beware in the literal meaning of the word. If it happens on the highway, it will be difficult to avoid an accident, but at a lower speed, a quick brake will save you…
When the CV joint is out, it is almost impossible to drive the car! Initially it is very difficult to turn the steering wheel to the side from which it came out. Nevertheless, it is still possible to drive for a while (about half an hour). Then the car simply stops and can no longer move.
At the same time the car starts up as usual, the speeds are enabled, but none of them responds. Initially, it may seem that the gearbox is out of order, but it is not. If you heard a loud rattle under any of the wheels, then it almost jammed (you are lucky, if it did not fly out completely), and then the transmission stopped working, it is 100% just a grenade – do not worry (it is necessary to change the CIA, not the box, which will cost much cheaper).
In any case, it is important not to bring your car to this state… It is better to repair at the first signs, than to pay for repair, and even wait a week for repair (being at that time without a car and having to move by public transport).
Well, now you know what a grenade in a car is and what it is. Now, after reading this article, you know how to check the internal CVG yourself, without overpaying for the services of professionals. We hope that this article was useful for you. We wish you good luck!
How to determine the malfunction of the internal CV joint.
Internal CV joint is one of the main mechanisms of the transmission of the car and for this reason, all elements of this unit should be made of quality materials. As a rule, the service life of elements is high. But, as practice shows, this mechanism, for various reasons, wears out prematurely. It happens even with the machines which have recently left the assembly workshops.
The reasons for this may be different: 1. Poor quality or total absence of lubricants on elements; 2. Absolutely low quality of the material of which a joint was made, and also use of counterfeit and rejected spare parts; 3. Falling into the mechanism of various garbage and water because of damage of dust covers; 4. Terrible road surface of our roads, aggressive driving of a vehicle on these roads; 5. Late acquisition and replacement of spare parts. Non-observance of rules of vehicle use specified in the instruction manual.
Initial diagnosis involves a superficial inspection of the mechanism. This is how you can determine if the dust cover is broken and if there is a characteristic sound (crackling). For a more detailed diagnosis, the constant velocity joint must be disassembled. To perform such diagnostics well suit a pit or a high trestle, but in those, as practice shows, not rare cases where they are not available, you can use a jack. Carry out the diagnostics of joints yourself is not too difficult.
A characteristic noise (crunch) known to many drivers. The sign – the balls are worn out. They are so worn out, that they freely roll over the grooves. This sound can be heard especially when turning, suddenly accelerating or when passing obstacles; 2. To be sure in the presence of play take the hand and move it in different directions. If there is the presence of defects and development of the mechanism, you will feel a significant play in the working area of the joint. 3. Failure of joints can occur due to lack of lubricant inside the mechanism; 4. Dirt, water, sand and everything else that can be on the track, gets on the hinge and eventually leads to its unserviceability.
Determining the crunch from the external CV joint. You need to pick a flat area to drive the car on. Turn the wheels to one side as far as they will go and drive off sharply. This will put a big load on the joint, and if it is faulty, you will hear the familiar sound. By the way, you can listen to it by yourself (with open windows) or with an assistant, so he could be near the wheel while the car is moving. The second case is especially good for diagnostics of the right joints, as the sound from there reaches the driver worse. However, such procedures can be performed on the road or in the “field” in order not to bother and not to look for an additional place for the tests. The right external CVD will crunch when turning the car to the left, and the left one – when turning to the right. This is due to the fact that at this moment, the corresponding joints are the most loaded, since most of the car’s weight is transferred to them, subject to significant torque generation. And the heavier the load, the louder the sound. However, in rare cases it is vice versa. That’s why it’s advisable to listen to which side the noise is coming from, outside the car.
How the internal CV joints crunch. Internal joints are diagnosed differently. To define which joint is defective, left or right, you should find a straight road with considerable potholes and drive over it. If the joint is broken, it will “knock”. Let’s describe another interesting method of determining how the internal CV joint crunches, which consists in not putting the wheels out, but significantly weight the back of the car (to put a lot of people, load the trunk), that is, to do so that the front of the car rose, and the axis of the internal CV joint as much as possible bent. If in this position you will hear a crunch in motion, it is one of the signs of failure of the mentioned node. In standard car operation, it is not recommended to constantly drive with the front of the car raised high, that is, do not load the rear part of the car heavily. Keep an eye on the shock absorber springs, spacers.
Universal diagnostic method. We present you the algorithm of another, universal variant, how to find out which “grenade” is crunching. You should act in the following sequence: Put the wheels of your car straight. Hang one of front wheels with a jack. Put the car on handbrake and in neutral. Start the engine, depress the clutch, engage first gear and slowly release the clutch, i.e. “move off” (as a result, the suspended wheel will start rotating). Slowly depress the brake pedal, creating a natural load on the joint. If one of the internal “joints” is defective, at this time you will hear the familiar knocks from the left or right side. If internal CV joints are alright, the car will start to stall. Turn the steering wheel all the way to the left. Slowly depress brake pedal. If the inner “grenade” is defective, it will continue its knocking. If the outer left CVG is also defective, the sound will also come from it. Turn the steering wheel all the way to the right. Carry out the same procedures. If there is a knock when you unscrew the steering wheel to the right, it means the right external joint is defective. Remember to put in neutral gear, stop the engine, and wait for the wheel to come to a complete stop before you put it on the ground. Follow the safety rules when aligning the wheels and diagnosing the CV joints, in particular, don’t forget to put the car on the handbrake, or better yet, use the wheel chock
Definitely in failure of joints you can be convinced at appearance of jerks when starting a car and change of its dynamics. But it is better not to bring the car to such condition.
