Cardan shaft "KamAZ": repair and replacement

Trucks created at the Kama Automobile Plant are known to all due to their high power, good cross-country ability and versatility of application. This was achieved with the help of high-power engines and transmission system. We will not consider the arrangement of the entire transmission, we shall stop on the cardan gear. Let's look at the KAMAZ cardan shaft, its device, and also learn how to properly repair and change it.

Cardan gear in KamAZ vehicles

This system serves to transfer the rotational energy from the drive shaft of the gearbox or the transfer case shaft to the shaft located on the drive axle. Cardan gear is used when it is necessary to transfer the torque, if there are different angles and distances between the shafts.

So, the chassis on three axes is the rotational energy or the torque to the rear, and also the intermediate shaft is transmitted by means of one common shaft. The intermediate bridge in this case is the gateway. And energy of rotation on a shaft of the back bridge is transferred by means of an additional shaft.

So, the cardan gear in this case consists of two shafts.

In addition, that this transmission transfers energy to rotation by bridges, it also gives torque to other mechanisms. This can be, for example, the winch drive. Also in these cars is the steering cardan shaft "KamAZ".

On those of the models on which the cross-country characteristics are improved, a leading front axle is installed. There also cardan joints are applied.

How is the cardan gear arranged?

Cardan shaft "KamAZ", as well as cardan joints - this is how this transmission is arranged. There is nothing complicated. Any hinge in this mechanism has in its design a fixed or sliding fork, fork-flange, as well as crossings, which are mounted in the forks of forks. Crossings are set on needle bearings. These bearings have seals so that the grease does not fall outside and does not come out of the cage. For this purpose two special radial shaft seals are used - they are built into the bearing, as well as ordinary oil seals. As a seal, a two-edge seal is used for the mechanical seal.

If the lead fork will rotate evenly, then the slave will not rotate evenly. While the drive shaft "KamAZ" will make one revolution, the driven fork will be twice ahead of the leader, and for the same two times it will lag behind it.

This is one of the reasons for increased loads on the design and main components of the main transmission in the transmission system, differential, wheels and semi-axles. This significantly increases the wear and tear of important parts and components.

Cardan gear is necessary to prevent this wear. But this transmission has on the two ends of the shafts special hinges. If you use forks for two joints on the driveshaft within the same plane, the uneven rotation that creates the first joint of the cardan gear can align with the speed of rotation of the second hinge.

Cardan gear on models 4310 and 43105

In these models, the wheel formula is 6 * 6. Also these cars are distinguished by the presence in the design of a sequential through-drive on the rear axles. The transmission here consists of four shafts. This cardan shaft is the main "KamAZ" - between the gearbox and transfer case, the shaft of the intermediate drive, and the shaft to the front axle. An intermediate shaft is installed in the intermediate bridge, which, through a system of shafts and hinges, transfers the energy of rotation to the rear drive axle.

The device of the cardan transmission on the "KamAZ" 5320

On these models of heavy-duty vehicles, the KAMAZ front drive shaft drives the middle drive axle as well as the rear axle.

They are connected through the middle bridge, which works as an intermediate support.

Each transmission has in its design directly the shaft, also the front hinge, which is connected by splines. The hinge has a flange connection to the drive shaft of the center differential.

PTO Drive Shaft Assembly

The design of the propeller shaft uses a movable splined joint. They allow you to ensure the necessary changes in the length of the shaft at the time when the car is moving. To ensure that the spline connection can be reliably protected from dirt, dust and water, it is sealed. For lubrication a special internal cavity is used. It is securely rolled up so that the lubricant does not leak out. Rings made of rubber and felt are also used for additional sealing.

These shafts are produced and assembled in such a way that those nodes that will not move, as well as the sliding parts could be located within the same plane. To do this, on the bushes of the shafts, as well as on sliding forks, special arrows are knocked out. For proper operation, these arrows must be aligned after assembly.

Maintenance and repair of KAMAZ cardan shafts

In order for the cardan gear and all its components to work reliably, it is necessary to check the tightness of all connections regularly. When carrying out maintenance, usually tighten all the bolts on the flange mounts on the shafts.

Also, during long-term operation needle bearings and necks of cross-pieces can be subject to wear. All this is accompanied by accelerated wear of the seats in the forks and splines.

When servicing parts and transmission units, you should carefully check the backlash in the hinges and eliminate them.

On the cardan shafts are mounted hinges. They require regular care and lubrication. For this purpose, a grease nipple is provided in the design.

Typical malfunctions

Repair kardannyh shafts "Kamaz" may be required, if during the movement can be heard characteristic knocking at the time of a sharp change in driving mode. Often, the vibrations in these mechanisms are a result of the use of shafts on which balancing is disturbed. This can be caused by the wear of the hinges at the joints. Also, repairs are required for various deformations of the shaft tube, loss of balancing plates, incorrect installation.

Loose joints often lead to the appearance and then the increase of the gaps between the flanges, the development of holes and the breaking of bolts.

Malfunctions of crosses

Exceeded safety factor most often can affect exactly such details as the spider of the KAMAZ gimbal shaft. These nodes are quite sensitive to all kinds of contact voltage. If the studs of the part have insufficient hardness, sooner or later, dents from the bearings will form on the surface. This can be expressed in the nonparallelism of the support surfaces on the hinge. The lack of parallelism will very quickly destroy the hinge. These faults can then lead to a complete destruction of the crosspiece. Then there can be an accident.

Replacement of the spider of the KAMAZ gimbal shaft

To replace this part you need some tools. These are carabiners, as well as socket wrenches, screwdrivers, a grease gun, a hammer, a metal brush, a copper or aluminum insert.

If all the tools are available, then you can begin the replacement work. Also, in this work, there will be no need to help a neighbor in the garage. The first thing to do is to disassemble the driveshaft.

How to disassemble a propshaft?

Find a pit or trestle. Then, using the appropriate key, twist the two bolts that attach the suspension bearings to the transverse supports. Then unscrew the nuts securing the shaft to the shank on the rear axle. It is worth buying a set of suitable nuts. It often happens that nuts have to be knocked down by force and crude methods.

Then you can proceed to the dismantling. Do not forget that you need to set labels on each part.

This is done in order to better remember the place where this or that node was installed. If you mount the shaft wrong, then the runout will be ensured.

After all the marks are marked, you can go to the replacement. First remove the locks or locking rings and install the cardan so that the rings are on top. Then use a hammer and mandrel to knock out the cup. Beat carefully. Do not exert excessive effort. With all the other cups you need to do the same.

The next step is to clean the eyes. Now you can also lubricate everything thoroughly. The grooves for the retaining rings must also be lubricated.

Self-replacement

The most difficult thing here is the correct installation of a new cross in its place. And to collect the shaft is not difficult. It is necessary to use a lot of lubrication when assembling.

In order to install the crossbar correctly, it is recommended to remove two opposing cups, and then fill the new part in the lugs. Then it is necessary to move the part to the side and at the same time to put on the cup.

Work neatly, otherwise there is a risk of spilling out needles from the bearing race.

Then you need to collect everything in reverse order. The main thing is attention, accuracy and lubrication.

Replacement of propeller shaft "KamAZ"

How to disassemble the shaft, already written above. Everything is done according to this principle, but instead of a worn or deformed shaft, a new one should be installed, replacing the grease and seals.

It is worth noting that when assembling it is not recommended to use a hammer, but you should use a hand press.

It is recommended to replace it with the completely new propeller shaft "KamAZ". The sizes of the parts that are sold in stores are completely suitable for most modern models.

Do not place second-hand parts

With this substitution, there are certain risks. Buying already used shafts, it is impossible to know how good they are. To minimize this risk, you should make sure that there are no backlashes and beats in the detail, as well as other possible problems.

The Importance of Balancing

The shafts in the cardan gear are not ideal. They can have different imbalances. This is a dangerous phenomenon. Among the external signs of poor balancing are vibrations, which at various engine speeds can then decrease, then increase. If the vibration changes depending on the speed of movement, then unambiguously - the shaft is poorly balanced. This problem can be solved on a suitable SRT.

So, we found out what the cardan transmission in KamAZ is for, and how to replace it with our own hands.