In detail: do-it-yourself cardan joint joint repair from a real master for the site my.housecope.com.
The constant velocity joint (CV joint), which is usually called simply "grenade", performs an important function and is the most important unit of the car. The CV joint transfers torque from the gearbox to the drive wheels, while setting the direction of movement. That is, in addition to rotation around the axis, the CV joint must be able to rotate, usually the angle of rotation is limited to 70 degrees.
Based on the purpose of the CV joint, we can conclude that it is used in cars with all-wheel and front-wheel drive (that is, in those with driving wheels setting the direction of movement).
The overwhelming majority of modern cars have front-wheel drive or all-wheel drive, so it will be useful for every car owner to understand the construction of CV joints and their possible malfunctions. Further, in the article we will briefly describe the device of the SHRUS drive, as well as its most frequent malfunctions and their causes.
Before starting any repair work or trying to diagnose a problem, you need to be clear about what you are dealing with. Therefore, below you will see a photo of the CV joint drive, on which its elements and their names are signed:
For a complete understanding of the structure of the drive elements, below you will see its cross-sectional image:
This unit is very reliable: under normal operating conditions, its service life may exceed the service life of the rest of the vehicle. However, the ingress of a small amount of dust, dirt, or water into the hinge multiplies the friction in the hinge, thereby increasing wear and tear and accelerating failure. Due to their importance for the normal operation of the car, CV joints are well protected by special "protective covers" - anthers. They provide the hinge with reliable protection from dust and dirt, as well as complete tightness. Anthers are usually made of dense rubber or plastic and are secured to the drive shaft with clamps. By the way, anther clamps usually have a slightly unusual appearance. In the photo below you can see the clamps for the anthers, a special device for tightening them and the tightening process itself:
Video (click to play).
One of the main reasons for CV joints malfunctions is connected precisely with the ingress of dirt or water through damage in the boot. If it happens that your boot is damaged and dirt gets into the hinge, you must immediately inspect it and then clean it (if necessary, repair it). To do this, you need to remove the drive, flush all its elements. Next, make sure that there is no excessive wear in the elements and install them back after filling the CV joint with fresh grease.
Repairing a damaged boot can be done with a regular tire patch and sealant. You can also use the repair method as in the video below:
There are two ways to detect possible malfunctions in the external (external) CV joint:
visually detect a violation of the integrity and tightness of the boot: cracks, breaks, traces of grease on the outside;
by characteristic sounds (characteristic crackling, crunching) when turning the steering wheel, entering a turn, etc.
If you disassemble the outer CV joint and find wear and tear on one of its components, then there is an opportunity to significantly extend the life of the joint without replacing it. First of all, if you find wear on the cage at the points of contact with the balls, then there is no point in panicking. The rolling bodies are installed in it with a gap, and a significant one, so that the development at the points of contact is completely harmless. It is another matter if wear appears on the rolling elements themselves or elsewhere in the separator.
If only the rolling elements are worn out, then their repair is not possible.But it will not be difficult to find the same ones at the nearest auto analysis, car market or auto shop. The main thing is to choose the balls of the required diameter.
If the separator is worn out, then there are two main repair methods:
replace the entire outer CV joint;
replace the separator;
change the SHRUS places.
The first method is simpler and more preferable, although it will turn out to be more expensive than the second. A lot of articles have been written about how to properly replace the outer CV joint and many video tutorials have been filmed. There can be many features and subtleties associated with each specific car model.
The second way is to purchase a repair kit (which are produced mainly for domestic cars) or find an outer CV joint for your car on analysis, remove the separator from there and install it in the old CV joint. Naturally, before installing a used separator, you need to make sure that there are no visible signs of wear. Next, immerse it in a rust converter if there is any trace of corrosion on it. It will be useful to clean it with sandpaper after that.
The essence of the third repair method is to rearrange the grenades of the left and right semiaxes in places. This will help, because the direction of rotation of the rolling elements will change (there will be unused portions involved). However, this will result in a crunching sound when reversing.
Another "tricky" method that allows you not to spend money on the purchase of the entire CV joint or its components. However, not every car can be “repaired” in this way. Its essence is to replace the outer cage separator with the inner cage separator. Here, of course, there are two conditions:
First, the separators must be identical to each other.
Secondly, the outer wear should not be too strong, and the inner (ideally) should have almost no wear.
Since these two conditions are not met on all car models, therefore, such repairs can not be performed on any car.
The inner CV joint, as well as the outer one, is protected by a boot. Accordingly, if its integrity is violated, dirt and water gets into the hinge, which leads to its failure. The methods for repairing internal CV joints in this situation do not differ from repairing external ones: they must be washed, replaced with grease and replaced with a damaged boot.
Another main problem of the internal constant velocity joints is the backlash of the drive shaft from the gearbox side. Visually, the difference between "normal" and backlash can be seen in the video below:
