Trucks created at the Kama Automobile Plant are known to everyone due to their high power, good cross-country ability and versatility of use. This was achieved using high-power engines and a transmission system. We will not consider the device of the entire transmission, we will focus on the driveline. Let's look at the KamAZ propeller shaft, its device, and also learn how to properly repair and change it.
Cardan drive in KamAZ vehicles
This system serves to transfer rotational energy from the drive shaft of the gearbox or the transfer case shaft to the shaft located on the drive axle. Cardan transmission is used when it is necessary to transmit torque, if there are different angles and distances between the shafts.
So, the chassis on three axes rotational energy or torque to the rear, as well as the intermediate shaft is transmitted using one common shaft. The intermediate bridge in this case is the passage. And the rotation energy is transmitted to the rear axle shaft by means of an additional shaft.
So, the cardan drive in this case consists of two shafts.
Besides the fact that this transmission transfers energy to rotation on bridges, it also gives torque to other mechanisms. This could be, for example, a winch drive. Also in these cars the KamAZ steering propeller shaft is used.
On those models that have improved cross-country performance, a leading front axle is installed. Cardan joints are also used there.
How is the driveshaft arranged?
KAMAZ driveshaft, as well as cardan joints - this is how this gear works. There is nothing complicated here. Any hinge in this mechanism has in its design a fixed or sliding fork, a flange fork, as well as crosses that are mounted in the ears of the forks. Crosses are planted on needle bearings. These bearings have seals so that the grease does not get out and out of the cage. For this, two special radial control glands are used - they are built into the bearing, as well as ordinary glands. Another seal used is a double-lip seal for the mechanical seal.
If the driving fork rotates evenly, then the driven fork will not rotate evenly. While the KamAZ propeller shaft makes one revolution, the driven fork will overtake the drive two times, and will lag behind it the same two times.
This is one of the reasons for the increased loads on the design and the main components of the main transmission in the transmission system, differential, wheels and half shafts. This significantly increases the wear of important components and parts.
A driveline is necessary to prevent this wear. But this transmission has special joints at the two ends of the shafts. If you use the forks for two hinges on the driveshaft within the same plane, the uneven rotation that creates the first hinge of the cardan drive will be able to align with the speed of rotation of the second hinge.
Cardan drive 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 gear here consists of four shafts. This is the main “KamAZ” drive shaft - between the gearbox and the transfer case, the intermediate drive shaft, as well as the shaft on the front axle. A through shaft is installed in the intermediate bridge, which transfers rotational energy to the rear drive axle through a system of shafts and hinges.
Cardan device at KamAZ 5320
On these models of heavy vehicles, the KamAZ front driveshaft drives the middle drive axle as well as the rear.
They are connected through the middle bridge, which works as an intermediate support.
Each gear has in its construction directly a shaft, also a front joint, which are connected by means of splined joints. The building hinge has a flange connection to the drive shaft of the center differential.
Drive shaft device
Cardan shaft design uses movable splined joints. They allow you to provide the necessary changes in the length of the shaft at the moment when the car is moving. So that this splined joint can be reliably protected from dirt, dust and water, it is sealed. A special internal cavity is used for lubrication. It is securely rolled so that the grease does not leak out. Also, rubber and felt rings are used for additional sealing.
These shafts are produced and assembled so that those nodes that will not move, as well as sliding parts, can be located within the same plane. To do this, special arrows are knocked out on the shaft bushings, as well as on the sliding forks. For proper operation, it is necessary that these arrows after assembly are combined.
Service and repair of propeller shafts of KamAZ
In order for the cardan transmission and all its elements to work flawlessly, the tightness of all joints should be regularly checked. During maintenance, all bolts on the flange mountings on the shafts are usually tightened.
Also, long-term operation may cause needle bearings and cross-neck joints to wear out. All this is accompanied by accelerated wear of the seats in the forks and spline joints.
When servicing parts and transmission units, one should carefully check the joints in the hinges and eliminate them.
Hinges are mounted on cardan shafts. They require regular maintenance and lubrication. For this, a grease fitting is provided in the design.
Typical malfunctions
Repair of KamAZ propeller shafts may be required if characteristic knocks are heard during movement at the time of a sharp change in driving mode. Often the vibrations in these mechanisms are a consequence of the use of shafts on which the balance is disturbed. This may be due to wear on the joints at the joints. Repair is also required for various deformations of the shaft pipe, loss of balancing plates, and incorrect installation.
Loose joints often lead to the appearance, and then to the increase of gaps between the flanges, the development of holes and the breaking of bolts.
Crosspiece malfunctions
Excessive margin of safety can most often be reflected in such details as the crosspiece of the KamAZ universal joint shaft. These nodes are quite sensitive to all kinds of contact voltage. If the spikes of the part have insufficient hardness, sooner or later, dents from the bearings will form on the surface. This can be expressed in the non-parallelism of the support surfaces on the hinge. Lack of parallelism will very quickly destroy the joint. These malfunctions can then lead to the complete destruction of the cross. Then an accident can happen.
Replacing the cross of the propeller shaft of KamAZ
Some tools will be needed to replace this part. These are open- end wrenches as well as socket wrenches, screwdrivers, a grease gun, a hammer, a brush for metal, a tip made of copper or aluminum.
If all tools are in stock, then replacement work can begin. Also, the help of a garage neighbor will not be out of place in this work. The first step is to disassemble the driveshaft.
How to disassemble the driveshaft?
Find a pit or flyover. Then use the appropriate key to twist the two bolts that secure the outboard bearings to the transverse bearings. Then unscrew the nuts securing the shaft to the shank on the rear axle. It is also worth buying a set of suitable nuts. It often happens that the nuts have to be knocked down using forceful and crude methods.
Next, you can proceed to dismantle. Do not forget that on each part you need to set labels.
This is done in order to better remember the place where this or that node was installed. If you mount the shaft wrong, a runout will be provided.
After all the marks are affixed, you can proceed to the replacement. First remove the clips or snap rings and install the cardan so that the rings are up. Next, use a hammer and a mandrel to knock out the cup. Beat it gently. Do not make excessive efforts. With all other cups you need to do the same.
The next step is to clean the eyes. Now you can also carefully lubricate everything. The snap ring grooves must also be lubricated.
DIY replacement
The most difficult thing here is the correct installation of a new cross in its place. It’s easy to assemble the shaft. Be sure to use a lot of grease during assembly.
In order to install the crosspiece correctly, it is recommended to remove two cups opposite each other, and then fill the new part into the eyes. Further it is necessary to shift a detail aside and at the same time to put on a cup.
Work carefully, otherwise there is a risk of spitting needles out of the bearing race.
Next, you need to collect everything in the reverse order. The main thing is attention, accuracy and lubrication.
Replacing the propeller shaft of 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 with the replacement of grease and seals.
It is worth noting that it is not recommended to use a hammer during assembly, but use a hand press.
It is recommended to replace it with a completely new KAMAZ driveshaft. The sizes of parts that are sold in stores are fully suitable for most modern models.
Do not place a used part
With such a replacement, there are certain risks. When buying used shafts, it’s impossible to know how good they are. To minimize this risk, you should make sure that there are no backlashes and beats in the part, as well as other possible problems.
The importance of balancing
The shafts in the driveline are not ideal. They can have various imbalances.
This is a dangerous phenomenon. Among the external signs of poor balancing are vibrations, which at various engine speeds can either decrease or increase. If the vibration changes depending on the speed of movement, then definitely - the shaft is poorly balanced. This problem can be solved at a suitable service station.
So, we found out what the universal joint drive in KAMAZ is for, and how to replace it with our own hands.