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Alternator pulley: appointment, installation, repair

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Alternator pulley: appointment, installation, repair
Alternator pulley: appointment, installation, repair

The generator is a complex system that includes many parts. Like any other components, it is prone to breakdowns, which negatively affects the operation of the car.

alternator pulley

Causes of breakdowns

The most common cause of a malfunction is a failed alternator pulley. It is designed to protect the system from vibrations and provide the necessary belt tension. Belt drive tension can change even with minimal pulley deflection.

It is not uncommon for the inside of a pulley to begin to wear away, causing cracks in the fasteners. At the same time, a backlash occurs, which contributes to the disruption of the clutch and the rupture of the belt itself. Also among the common breakdowns are the following:

  • belt slip;
  • changing the overall geometry;
  • excessive damage to the center section;
  • plane curvature;
  • scratches and cracks.
vaz generator

What role does the VAZ generator pulley play

Car operation involves continuous movementcrankshaft, the operation of which can be disrupted even due to minimal vibrations. The alternator pulley protects the alternator and reduces the noise generated by the belt drive movement. In addition, its function is to reduce the load on the generator, so that it wears out much more slowly even at high speeds. This is why regular pulley checks are so important to prevent many vehicle breakdowns and extend the life of expensive parts.

Progress of work

Simultaneously with the pulley, the VAZ generator itself is removed, so special care must be taken when working. Before dismantling the device, remove the drive from the negative terminal and remove the belt. This can be done by loosening the adjusting bolt and unscrewing the top and bottom radiator mounts. Next, the generator is shifted directly to the cylinder block. Now it remains only to carefully remove the belt from the pulley and crankshaft.

The plug with wiring is removed from the generator connector, the cap is removed, and the nut is unscrewed. Then the wiring is dismantled, which is the connecting element of the “B” terminal and the contact latch. You also need to get the tension bolt, which is located on the front and is necessary for attaching the generator. The next step is to remove the nut and the threaded sleeve.

Bottom mount includes spacer and nut. For further work, it is recommended to use third-party assistance to simplify the removal of the last fastener,located under the generator.

VAZ alternator pulley

Possible problems

Replacing the alternator pulley can be significantly complicated if it is not replaced in time due to its oxidation, as a result of which it sticks to the generator itself. You can simplify the task with a tool with a small-slotted profile. To remove corrosion, it is recommended to use brake fluid or a special tool. It is enough to apply a small amount of the composition before removing the damaged element.

If there is no special key, you will have to use another method. To begin with, the rotor shaft is fixed to prevent it from scrolling. Next, the nut is removed, which holds the alternator belt pulley and the part itself to be replaced. All work is done with the help of two tools: a hexagon and an end head of a suitable size.


The generator pulley, the price of which can reach up to 4 thousand rubles, is a rather fragile part and therefore can become unusable even with minor damage. This is due to the fact that this element is not hardened during production. The breakdown is also facilitated by a small backlash that appears during the operation of the car. That is why special attention is paid to the reliability of fastening the part during installation. Also, during production, microscopic scratches may appear on the surface of the element, which expand during operation and reduce the life of the part.

It is worth noting that you can repair the generator pulleyonly if there is minimal damage. After removing the part, it must be carefully inspected and pay attention to the condition of the generator itself in order to promptly eliminate breakdowns.

Proper pulley function has a direct impact on battery performance. In the presence of malfunctions, there is a frequent need to charge the battery and a quick failure. By repairing or replacing the alternator pulley in time, you can change the gear ratio and reduce fuel costs, this is due to the fact that the part will rotate more slowly when idling than when the car is moving.

alternator pulley replacement

What you need to know

Car owners often face a small backlash, which anyone can fix. It should be noted that the operation of a heavily loosened pulley is impossible and must be replaced. Backlash can be eliminated due to a tighter connection between the generator and the mounting bolts. It is recommended to inspect the surface of the part, if small cracks are found, they must be soldered.

The protective cover of the element is used only once and for a certain period of time recommended by the manufacturer. A new cover should be purchased before the expiration date. As noted earlier, repairing and replacing a pulley does not require special skills and even an inexperienced owner can do it. In this case, it is recommended to use a special removable tool that will not only speed up the task, but also simplify it.

alternator belt pulley


When inspecting the VAZ generator for malfunctions and damage, it must first be cleaned of dirt and dust. To begin with, it is worth making sure that the contact between the brush and the output is reliable using a tester. It is enough to connect one probe to the terminal, and the other to the brush itself, setting the ohmmeter mode. Contact failure is detected by a break and high resistance. In this case, it is necessary to solder the connection points of the terminals and brushes.

It is recommended to clean slip rings with solvent. The black coating from coal dust appears more intensely if there are scratches, notches or steps on the rings. Irregularities can be removed by turning the contact elements, which are fixed in the lathe.

It is worth noting that zinc chloride cannot be used for soldering. It is not suitable for the repair of any elements of electrical equipment, as it contributes to the intensive development of corrosion and a decrease in the service life. The best option would be the usual rosin.

It will not be superfluous to check and springs. During operation, under the influence of high temperatures, their elasticity decreases, which makes it necessary to replace them. To check, just press on the brushes that are visible from under the brush holder.

generator pulley price

Russian and imported generators

The principle of operation of all modern generators is the same and is based on the generation of alternating current and subsequent conversion to direct energy. Each model is equipped with a built-in diode bridge.

Main differencebetween generators of domestic and foreign production is the lack of additional rectifiers in Russian devices used to power the winding.

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