Chain tensioners for car

The engine timing mechanism is designed for timely supply of fuel mixture and exhaust gas to the engine cylinders. The valve mechanism is driven by the rotation of the crankshaft. In this case, the torque from the crankshaft is transmitted to the distributor by means of a belt or chain. It depends on the model of the car. But, as a rule, on the majority of modern cars establish a gear belt. The timing chain is installed on earlier models, such as VAZ-2101-07. Unlike the belt drive, the chain drive is more reliable, but it has its drawbacks, one of which is the high noise of the distributor mechanism with a weakened drive.

Purpose of the timing belt tensioner

To ensure the normal operation of a drive element such as a chain, chain tensioners are installed in the engine design. During the operation of the car, the drive chain of the camshaft drive and its tensioner fail quite infrequently, but still it happens.

Often the chain simply stretches, at this point in the motor there is a noise in the area of the clamp. If the chain drive is ruptured or slipped, a more serious engine breakdown can occur, which will entail expensive repairs. To prevent this, it is important to monitor the condition of the drive and maintain the timing chain tensioner in a timely manner.

Features of the mechanism of the tension mechanism

Let's consider a construction on an example of auto VAZ of the seventh model. The machine has a plunger-type pulling device. The required degree of tension is due to a plunger with a spring.

Operation of this device is as follows - under the influence of the pressure of the spring, it exits from its seat and rests against the chain tensioner shoe. Thus, the part pushes the shoe until the moment when it meets the resistance of the clamp. Due to the action of a powerful spring, the sagging of the drive disappears and tension occurs. In this case, after adjusting the tension, the plunger of the mechanism is locked with a biscuit. During prolonged use, the auto chain is gradually stretched, and it must be re-tensioned. To do this, unscrew the lock nut of the plunger lock, after which the spring will again make a sample of the slack.

Chain tensioners of this type have one significant drawback.

Namely - the possibility of getting small particles of litter in the plunger seat, while increasing the likelihood that it will jam in the body. Eliminate such a malfunction by tapping the body of the mechanism with a wrench, sometimes this method of repair helps. If the tensioner body is damaged, it must be replaced.

Carry out a periodic operation to remove the sagging of the drive element is not always convenient, and in order to get rid of this procedure, motorists often install an automatic chain tensioner, which self-stretches as the chain retracts. The design features of such a device exclude the possibility of its jamming.

The device and operation of the automatic mechanism

A part of this type is equipped with a ratchet mechanism, due to which the sagging of the chain is automatically removed as it stretches. The tensioner consists of a body and a spring-loaded pawl of a ratchet mechanism. It is also equipped with a spring-loaded toothed bar. The teeth on the bar have a slope in one direction, and their pitch is one millimeter.

How it works

Depending on the degree of sagging, the clamping spring of the mechanism acts on the toothed bar, and it in turn - on the shoe of the chain tensioner. In this case, the return of the bar to its original position is impossible due to the pawl of the ratchet device.

The dog gets between the teeth of the bar and does not allow it to move back. Thus, the spring constantly acts on the bar and pulls the chain, and the ratchet mechanism does not allow to weaken.

Chain tensioner replacement

You can make a replacement at home. It is enough only to have a set of tools and, accordingly, a new tensioning element. This device is located on the outside of the crankcase of the engine, under the water pump. For repair work, you will need locksmiths and carob keys for ten and thirteen.

Dismantling the device

We put the car on an even surface and the parking brake. In order to remove the chain tensioner VAZ 'a, do not need to remove anything from the engine. It is enough just to unscrew the fixing nuts of this device and get it. At the same time, care must be taken not to damage the gasket.

Installation of a new device

If the mechanism is plunger type, then before installing it on the engine, you must dump the plunger into the housing.

To perform this operation, the chain tensioners are gently clamped in the yew. Then, with a 13-inch wrench, loosen the lock nut. After this, under the influence of the spring, the mechanism will move out of the housing. To push it back, the tensioner gets out of the yew. Holding the part in the hand, with the second hand, press the plunger into the housing and, holding it in this position, tighten the lock nut. After this, you can install the control mechanism on the engine. In order for the element to work and tighten, loosen the nut, and then tighten it.

We change the shoe of the chain tensioner VAZ 'a

To change the shoe is a bit more complicated than the tensioner itself. Here, in addition to dismantling the mechanism itself, it is additionally necessary to remove the pulleys of the gas distribution gears located in the front of the power unit.

Then there will be a need to remove the protective metal cover of the drive, the drive camshaft gears and the shaft of the auxiliary mechanisms. Only after the dismantling work is done can you begin to remove the shoe. Despite the type of engine power supply system, the chain tensioners do not have a significant difference in terms of their replacement.

Installation of automatic tensioner

When deciding to replace the standard device with a more modern removal of the first one, it should be done as described above. On the example of the "seven", it can be noted that an automatic chain adjustment device can be installed on the engine. Very good for this purpose is the tensioner chain "Pilot". As a rule, this mechanism is already sold with a working rod inserted into the housing, which has a fixation (pin) on the front side of the device. To begin with, you must install the automatic device on the motor, which occurs in the same way as the installation of the standard controller.

After installation, you need to pull out the lock pin with the pliers, and the spring will press the bar. Then screw the bolt into the end part of the body, which prevents the spring from falling out. Often this bolt comes complete with a tensioner device.

As you can see, the processes of replacement and installation of different types of tensioners are not very different in the sequence of execution, and you can make repairs yourself.

Tensioner for VAZ-21213

Previously, cars of this model were equipped with engines with tensioners, in the design of which a spring was provided. At present, these models are equipped with hydraulic tensioners drive. The plunger rod of the device is driven by the pressure of the oil. This type of device is also fully automatic and does not require human intervention to adjust the degree of tension of the clamp.

But, like any detail of the machine, the hydraulic chain tensioner ("Niva" is not an exception) can become clogged and damaged during operation, and it will have to be replaced.

The process of removal is carried out as on all VAZ cars up to the seventh model, with only one difference - the need to remove the hydraulic oil supply pipe, the supply of which is from the end of the part. To ensure that the oil does not flow out of the pipe later, it must be plugged with a piece of rag or a suitable bolt.

It is important to note that after dismantling the details it is worth checking for its further suitability, perhaps it's just clogged up. The oil that comes to the tensioner can carry soot, elements of metal and rubber parts, therefore the plunger rod can be jammed.

For cleaning, place the part in a small container of gasoline, allow it to stay in it for a while, then rinse it thoroughly and drain it with compressed air.

Inspect carefully the body and the plunger part of the mechanism for defects in the form of scratches and dents. In the absence of such tests, we perform an operation check of the device. We take it in hand, and the second we try to move the plunger in the body. The plunger rod must move smoothly and without any seizure. If the plunger movement is difficult, repeat the rinse again. When and after that nothing will change - replace it with a new one. Installation of the hydraulic part is carried out in the reverse order to removal.