All parts of the car structure have their own specific resource, which depends on the quality of the material and manufacturing technology. The drive for the generator is a belt. An optimally tensioned belt will last longer. When buying a belt, its resource is usually indicated, but if it is overtightened or not stretched, then the resource will be less than it should be, moreover, an incorrectly tensioned belt breaks rollers and bearings faster crankshaft and generator shaft bearings.

If the belt is not tensioned correctly

If the belt is loose

It often happens that the belt loosens during operation. In this case, with a weak tension, it will slip in the grooves of the pulleys. And if the belt slips, then the generator shaft has nothing to spin, no one forces it. And, if the generator shaft spins slowly or stops altogether, then it will not generate electric current. Hence the lack of energy for the power supply system of the car's electronic devices, which are becoming more and more every decade. What kind of sensors are not now in modern cars and trucks.

When slipping, both the alternator and the belt suffer. The friction belt heats up, peels off, scuffs, scratches, cracks appear. From this we conclude that the resource of the product depends on the method of operation.

If the belt is overstretched

With a strong tension of the alternator belt, the belt wears out even faster than with a weak one. The belt is okay, it wears out, it was replaced, but a tightened belt wears out the bearings of the crankshaft and generator shaft even more. The service life of the belt in this case will not reach the declared one. If there is little or more current supplied to the battery, then the problem in the relay is easy to do.

Checking the alternator belt tension

Each make and model of car has its own values ​​for the optimal tension of the alternator belt. In the instructions for the repair and operation of a particular machine, you can find information with what value to make the correct tension. Full of manuals in electronic format who doesn't have a book.

Not only the operation of the generator depends on the belt tension, but also additional equipment, for example, air conditioning, power steering (GUR), etc.

For most machines, the formula for determining the correct tension is as follows: in the middle of the belt between the pulleys, press with a force of 10 km by hand. In this case, the belt can be pressed through only 1 centimeter.

For example, VAZ 2115 has a regular generator 37.3701 and sometimes a generator 9402.3701 is installed. If the generator is coded 37.3701, then with a force of 10 kg on the middle of the belt, the belt should bend from 1 cm to 1.5 cm. And if the generator is 9402.3701, then with the same force, the belt should bend from 6 mm to 10 mm.

Why is the belt whistling?

Many probably heard the retinue from under the hood of the car. This is exactly the same sound that the alternator belt slips through the grooves of the pulleys. Some cars will notify the car with signals on the instrument panel, for example, a low battery light may come on.

From time to time it is necessary to open the hood and inspect the condition of the engine and other structural elements in the car body. During visual inspection and to the touch, if the belt hangs or is pulled, depending on the make and model of the car, you must correctly tension the belt with your own hands using the adjusting bar or adjusting bolt.

How to tighten the belt with an adjusting bar

The slat unit design is an obsolete model. Old VAZ cars have such a bar for belt tensioning.

In this case, the generator is fastened using an arcuate bar. This bar has a slot, due to which it moves relative to the bolt.

Sequencing:

1. Loosen the nut.
2. Crowbar or something like that, we move the generator.
3. After setting the desired tension, tighten the nut and the arcuate bar is fixed.
4. After tightening the nut, check the tension again.

How to tighten the belt with an adjusting bolt

This is the most common generator mounting and belt tensioning design. The sequence of work is as follows:

1. Loosen the top and bottom fasteners of the generator.
2. By unscrewing or tightening the adjusting bolt, we move the generator and set the desired belt tension.
3. Tighten the alternator mounting bolts.
4. Check the tension again.

How to tighten the belt with an adjusting roller

Some designs have in their arsenal a special roller for tension control. It makes adjustments faster.

As an example, consider how to tighten the belt on a Lada Priora with air conditioning and power steering.

Tools:

First, use a 17 key to unscrew the bolt and loosen the roller. Then we loosen or tighten the belt with a special key. Then we fix the video.

After adjusting the tension of the alternator belt, you need to start the engine, turn on the car's electronics and observe if there is a whistle of the belt, if all the devices are working (is there enough current generated by the generator).

How long to tighten the alternator belt

Basically, tightening the belt should be done every 15 thousand kilometers. And the alternator belt should be changed every 60 thousand kilometers. The belt gradually stretches by microns as it is used.

Belt tension on Nissan, Chevrolet, Kalina, UAZ, Gazelle, Renault, Grant, Toyota, Ford Focus, Opel, Mazda, Niva, VAZ 2107, VAZ 2110 cars is carried out by the methods discussed above, only some cars have automatic belt adjustment using built-in springs .

Conclusion

After creating the correct tension of the alternator belt, you need to start the internal combustion engine, observe the work. After not long-term operation check the belt again. There are defective belts that quickly delaminate.

Video

In this video about tensioning the belt on the Priore.

Another way to stretch car Lada Priora.

We found the cause of the belt squeak in the tensioner warp.

Incorrect alternator belt tension can cause a lack of charging. The ability to determine the correct tension force will be useful as when repairing with your own hands, and in the event of a fire on dashboard.

What is the degree of tension

Excessive force will cause the alternator bearings to fail soon. A breakdown in the initial stage manifests itself as a hum from the generator. When replacing the belt, it is advisable to check the condition of the bearing. To do this, spin the pulley by hand. Rotation should be uniform and silent. If the hum operation of the internal combustion engine nevertheless appeared, you can remove the belt, and then for 10-15 seconds. start the motor. So you can determine if the noise is coming from the generator bearing or timing rollers.

Insufficient tension leads to belt slippage and accelerated wear. The first sign of such a malfunction manifests itself as a squeak when cold or when wet. Overstretching will result in no charging. That is why it is important to know how to check the tension of the alternator belt.

Construction types

The drive is of two types:

How to determine the correct degree of tension:

Tension

How to properly install a car alternator belt, consider the example of two types of construction:

• loosen the tensioner bolt by unscrewing the locknut. Rotating the bolt itself will tighten and loosen the belt. After setting the tension, fix the tensioner bolt with a wrench and tighten the lock nut;
• loosen the bolts securing the generator to the brackets. Lay a pin between the generator housing and the engine. Pull the belt with the force of the lever, after which you can tighten the fastenings of the generator;
• systems with a single service belt drive can be tensioned automatically. A special tensioner is located in the design, to loosen it, it is necessary to unscrew the roller bolt, and then remove the tensioner with a wrench.

In the case of a ribbed belt, before the final check of the degree of tension, start and stop the engine. This will ensure that the belt is in the correct position in the pulley grooves.

Absolutely any, more or less, experienced driver knows that the correct tension of the alternator belt will provide a reliable power supply to the vehicle's on-board network and a good one, which is so important when starting the engine. A loose belt can slip relative to the alternator pulley and quickly break due to heat, and a tightly tensioned belt creates a large load on the bearings of the generator rotor shaft and pump, as a result of which they quickly fail.

As you understand, such a parameter as belt tension should always be within the normal range. To check the tension of the belt, you can use a metal strip half a meter long and a simple ruler. Almost all domestic cars allow belt deflection, which is formed between the alternator pulley and the crankshaft, equal to 15 millimeters. The force, in this case, should not exceed 10 kg / cm.

Procedure:

1. To measure the tension of the alternator belt, place a thin metal strip between the crankshaft pulley and the alternator.

2. Act on the belt by pulling it away from the strip with your fingers.

3. Measure the distance from the highest position of the alternator belt to the metal strip.

The resulting value will mean the deflection of the alternator belt. If it has any deviations from the norm, then it will be necessary to adjust the alternator belt or replace it, depending on the degree of belt wear.

Alternator Belt Adjustment

So, if you come to the conclusion that the alternator belt tension is insufficient or excessive, then you need to proceed with the adjustments. It is performed quite simply, so you can do without car service employees.

Procedure:

1. Install the car on a level surface and exclude any accidental movement. The presence of an inspection pit is not at all necessary, however, if your car is a “classic” family, then it is better to use the pit. Disconnect the "negative" battery terminal to avoid accidental short circuits of current-carrying parts engine compartment(wires, plugs and housings of metal elements).

2. Loosen the nut located on the alternator adjusting bar. You do not need to unscrew it too much, since you only need to release the generator from fastening. Do the same for the bottom nut. It is screwed onto a long bolt, which is the main fastening of any generator.

3. Insert a prybar into the gap between the engine and generator and bend the generator, creating the necessary force on the belt. Without loosening the applied force, tighten the adjusting bar nut as tight as possible. After that, check the belt tension as described above. If the measurement result is not correct, then loosen the nut again and re-tighten.

4. Once the belt tension meets maintenance requirements, tighten the nut on the long bolt. This completes the alternator belt adjustment.

Video - How to tighten or loosen the VAZ generator belt

In the case when the tension of the alternator belt is impossible due to the strong wear of the rubber component, then it is necessary to replace the belt. relevant in the case when the belt is stretched or has any defects in the form of burrs and cracks. In addition, during operation, it can emit a characteristic whistle, by which it is not difficult to determine its faulty condition.

Before replacing, purchase the exact same alternator belt. A product from another car model will not work in any way - this must be carefully remembered.

Procedure:

1. Place the vehicle on a level surface and immobilize. The presence of a viewing hole, as in the first case, is not a mandatory, but a desirable condition. Be sure to disconnect the negative battery terminal.

2. Loosen the nut that secures the generator to the adjustment bar. After that, loosen the nut that tightens the long bolt from the bottom of the generator.

3. Pull the alternator towards the engine and remove the old belt.

4. Mounting a new belt looks more complicated. The most important thing is to make every effort, while not spoiling the product. First, it is recommended to put the belt on the crankshaft pulley, then on the alternator pulley. If there is a water pump pulley - last, put the belt on the pump pulley.

5. After that, tension the belt and tighten all loose nuts. Don't forget to put the battery terminal back in place.

This is how the alternator belt tension is checked, adjusted and replaced. This set of procedures is basic and is performed by a standard set automotive tools. This does not require special knowledge, so you can check the belt tension yourself.

The role of the generator in the power system of the car is one of the leading ones. In any vehicle the current generator is one of the most important nodes. It is responsible for the supply of electricity direct current 12 - 24 V) all mechanisms and components of the machine. The generator is also responsible for the safety of the battery and finding it in a constantly working condition. Therefore, checking the alternator belt tension should be carried out regularly, even if there are no obvious signs of belt loosening.

Signs of a weak alternator drive tension

First of all, with a weak tension, the belt begins to emit a characteristic “squeal” with a sharp increase in engine speed. This is especially noticeable when starting the car or when entering a turn, when an unpleasant squealing sound is heard at the moment of gear shifting. Another sign is the “flickering” of the headlights at night. With a properly running alternator with the correct tension, the headlights are even and bright. If the alternator belt tension is weak, in the dark, the headlights constantly change brightness when the engine is running.

Visual checks

A car enthusiast should know how to check the tension of the generator drive. This is simply the necessary knowledge for correct operation car. The alternator belt tension scheme for each engine model is different. It depends on the location of the unit on the engine. From the number of connected additional modules (hydraulic power steering, air conditioning drive, etc.). Therefore, the procedure for checking the tension for each motor model is different. For example, the j20a engine alternator belt is tensioned according to the diagram shown in the figure below.

Here, under No. 1, the drive belt itself additional equipment, #2 - tensioner roller and #3 - tensioner roller nut.

different ways settings mean different methods for checking the degree of tension, but there is a common feature. The test is done on the largest free area of ​​the drive. So, an experienced locksmith checks this parameter by slightly turning the ribbed belt by 45 degrees. At this angle, the belt goes without much effort. Then the resistance grows. V-belts bend relatively easily when pressed by 5 mm, further the force increases.

Important! Do not allow the alternator drive belts to be tightened. It leads to rapid wear bushings and bearings, failure of engine components and assemblies.

But of course, checking with the help of instruments is more reliable.

Ways of tensioning drive belts

On the various models engines have their own methods of tensioning the belts of the generator and other units. They are divided into three types:

• aggregate;
• roller;
• auto.

With the aggregate method, the tension of the drive occurs by moving the body of any unit on a movable basis. This could be the alternator itself, the power steering pump, or the air conditioning compressor.

The roller method assumes that the tension is produced by an eccentric roller. Due to the displaced axial hole, when the roller housing is rotated, tension is produced by displacement.

Finally, automatic movement alternator belt tension. This is the most advanced stretching method. The tension roller is mounted in a mechanism with a powerful spring with a precisely calculated force. When installing a new belt, the roller is pulled to the side and released when it is in place. The spring resting gives the necessary tension.

j20a motor with auto tension

Important! With the automatic method, the belt does not require tightening or power checking. When weakened, it is only replaced. Which is very easy. The spring roller is retracted in the direction of weakening and the entire drive can be easily removed.

Specialized Belt Tension Checkers

To check the degree of belt tension, there are also special devices. They are divided into two types:

• mechanical;
• electronic.

Mechanical devices are made on the basis of the dynamometer principle. Using the built-in spring, the force applied to deflect or retract is measured. This parameter must be indicated in the vehicle passport. Therefore, this tool is available to any user. And it may well take a place in the arsenal of a simple motorist who tries to do at least part of the work on his car with his own hands.

Electronic devices are based on the principle of capturing high frequency sounds. The user, bringing the device to a certain point of the belt, strikes a light blow on its surface. The device picks up the vibration frequency and digitally displays the result on a mini screen. But the use of this device already requires deeper knowledge and skills. Therefore, it is more of a professional tool.

Such devices are already suitable for a reputable service station that cares about its reputation and is ready to spend money both on serious equipment and on training personnel to work with it.

Mechanical tension gauge

What threatens a loose belt

Weak tension of the alternator drive belt reduces, first of all, the strength of the battery charging current. With a weak charge, the battery's own internal resource is consumed and, accordingly, its service life is sharply reduced. Shedding of the plates or a short circuit may occur, and the battery modern type(not repairable) will only be thrown away. In addition, power surges with insufficient tension adversely affect all electronic systems current cars, up to their failure. A loose belt can simply slip off the pulleys and cause trouble at a high speed of rotation of the crankshaft pulley. He is even able to pierce the hood of a car.

Over tension

A very strong stretch will also not lead to anything good. There is an increased load on various rubbing parts of additional mechanisms. The first sign of constriction is an unpleasant hum. Most often, the alternator belt tensioner is noisy. But this is the least of the troubles that can happen. It is much worse when bearings of a generator, air conditioning compressor or power steering, or a water pump bushing begin to emit such noise. In these cases, the repair will be much more serious and more expensive.

Therefore, adjusting the alternator belt tension is a very important element in maintenance car. Even if an automatic tensioner is installed, as, for example, on the j20a engine or on the Peugeot 306, it is necessary from time to time to check the special marks on the belt tensioner housing, indicating the time to replace if necessary.

Tools and materials for the prevention of the generator drive mechanism

A variety of types of installation on various types of engines of a huge number different types generators does not allow to uniquely name a single tool for a given operation. As a rule, for each model it is different. Although there are some common features.

Tools

Usually, for the prevention of a drive with aggregate adjustment, wrenches are needed to loosen the mounting bolts of the assembly and a wrench to rotate the adjustment bolt. Plus a small pry bar to hold the knot in position. For roller drives, a wrench for loosening the roller nut and a special key for turning the roller itself. For an automatic drive, only a mount or a wrench to wring out the roller when replacing the belt and wrenches to replace the roller itself.

Belts and rollers

For each engine, there is both its own alternator belt tension roller, and the belt itself must be its own. All of them have special markings and their own signs.

Important! Installing parts that do not correspond to the purpose of this particular motor model can lead to major breakdowns with capital costs.

Therefore, the most reliable way to purchase spare parts is to identify the necessary parts by the VIN code. This is a modern way of obtaining spare parts and parts for the machine. Any vehicle has its own identification number located on a special body plate.

In normal auto parts stores, it is no longer mandatory to bring a broken part for identification (only in very rare cases). It is enough to dictate this code to the seller, and with the help of a special program, by contacting the global database of identifiers, the seller will confidently tell you the type and dimensions of the required part. If necessary, order the store to deliver it within an acceptable time frame. This is the best method to use to acquire needed by the car drives attachments and tension rollers.

Replacing the alternator belt with an automatic tension roller is well shown in the video using the Peugeot 306 as an example:

The article describes in great detail why the generator drive is tensioned and why it cannot be tightened or loosened strongly. Also given step by step procedure belt replacement and adjustment.

The operation of such parts in the engine as a water pump, crankshaft bearing and tension roller depends on how the alternator drive belt is tensioned. If the belt is loose, it will not produce enough current to recharge the battery. And if the belt is tightened more, then the generating device may break. The alternator drive belt is recommended to be changed every 15 thousand kilometers, or when the belt has cracks, rubber delamination and breaks. All procedures were carried out on a VAZ 2110 car, do everything the same on other brands.

• Also read about.

1. It is important that when checking the belt, the car is not running.
2. It is more convenient to work with the alternator drive belt under the car. Therefore, the front of the machine must be raised with a jack and the engine crankcase protection removed.
3. After that, you should press the belt up by hand in the center between the crankshaft and the generator pulleys, and the force should be approximately 10 kgf. Using a ruler, we measure the amount of deflection, which should be no more than 10-15 millimeters.

Tension adjustment

If the deflection does not match the numbers, then the alternator drive belt must be adjusted. For this you need:

The tension or loosening of the generator drive belt should be approached very competently, since with a large tension on the belt, the tension roller and the generator bearings, increased loads will be produced, which will affect their rapid breakdown. And if the tension is not enough, then the belt will slip on the pulleys, which has a bad effect on battery charging.

If the belt cannot be restored, then it should be replaced. To do this, you need to do the following:

1. Loosen the bolt on the upper and lower mountings of the generator, and unscrew the adjusting bolt as much as possible.
2. Move the generator as close as possible to the cylinder block.
3. Remove the loose belt from the alternator pulley and crankshaft.
4. The new belt must first be put on the pulley in the crankshaft, and then on the pulley in the generator. If the belt is worn with a stretch, then slowly turn the crankshaft until the belt is put on.
5. Tighten the bolts at the bottom and top of the generator mount.
6. Check belt tension.