VAZ 2114: replacing the main brake cylinder - a necessary tool, choosing a new GTZ

Normal operation of the braking system is the most important component of safe movement in any vehicle. The design of the VAZ 2114 includes front disc and rear drum brakes. To ensure their operation, the design includes a brake master cylinder. Over time, it begins to deteriorate, which affects braking performance. In the article we will look at how to replace the master brake cylinder of a VAZ 2114.

Useful video:

Symptoms of a problem

With a calm driving style and regular maintenance of the brake system, the GTZ will serve without interruption for many years. Cylinder output increases with frequent vehicle use in city traffic.

Useful : Replacing brake hoses on a VAZ 2114

Frequent and prolonged stops accelerate the wear process of the turbocharger, which is reflected in the manifestation of the following symptoms:

• When you press the brake pedal, the car stops slowly, although the fluid level and the condition of the discs and pads are normal;
• To effectively brake, you have to press the pedal with serious force;
• Short brake pedal travel is another sign of a worn cylinder;
• Sudden failure of the pedal and “grabbing” of the brake at the end of pressing;
• Incomplete disengagement of the calipers, which leads to friction of the pads on the discs.

The listed symptoms of a faulty master cylinder manifest themselves in different ways, but always mean there are problems with the braking system. The braking system in your car requires regular maintenance. Despite the simplicity of the design and reliability, diagnostics of the design should be carried out every maintenance. Regular replacement of pads, installation of new brake discs, replacement of fluid, elimination of leaks from pipes - all this ensures the smooth operation of the system as a whole. The GTZ plays a crucial role in this design, because Braking efficiency directly depends on the correct operation of the cylinder. In addition to the GTZ located under the hood of the car, there are other elements in the system that are responsible for stopping the car. Often, in addition to the main brake cylinder, it is necessary to replace the front brake cylinder on a VAZ 2114. It is located on each caliper and is responsible for actuating the pads.

A faulty front brake cylinder on a VAZ 2114 leads to a wedge in the mechanism and friction of structural parts. If the front TC fails, the car begins to move to the side when braking, and extraneous noise comes from the wheel.

Examination

You should make sure that the master cylinder is the culprit for the malfunction of the brake system. This is easy to do; you don’t even have to go to a service center and spend money on it.

Unit location

1. Press the brake pedal with the power unit off.
2. Start the engine without taking your foot off the gas pedal.
3. During normal operation, the gas turbine engine fails under the influence of vacuum.
4. If the pedal does not fail, you will need to conduct more thorough diagnostics and restore the device to functionality.

Most likely, you will need to restore the tightness of the return regulator connection. It is located on the intake manifold amplifier housing.

Repair kit or new GTZ?

Many car owners face a question when the brake master cylinder fails: how exactly to repair the brake master cylinder. After all, there are two main options:

• Purchase a new GTZ;
• Use repair kit.

First, let's take a look at the price tags.

Purchasing a repair kit and using it to restore the functionality of the brake cylinder entails uneven wear of old and new elements, breakage of rings and a number of other problems. In this regard, we advise you to eliminate the breakdown by completely replacing the gas turbine engine, and not by using a repair kit.

Necessary tools and spare parts

Repairing your car yourself allows you to save money and gain experience in car maintenance. Having a minimum set of tools allows you to repair most components and parts of the “four”. To replace the GTZ you will need the following tools:

• Keys at 10, 13, 17;
• Pliers;
• Rags and brush to remove dirt;
• Device for unscrewing fittings;

• Brake fluid and syringe for pumping it out;
• New GTZ.

If there are problems with this element, it is recommended to change the assembly mechanism, because Repair kits when installed in an old cylinder body will not give the desired result, because development inside it will not allow the new part to return to efficiency.

How does GTZ work?

The operating principle of the GTZ is based on the ability of a liquid to maintain its “shape” under the influence of a certain pressure. In this case, the devices structurally consist of a 2-section main cylinder, each section of which has its own hydraulic circuit.

Front-wheel drive vehicles consist of circuits that connect the braking systems of the rear and front wheels in a criss-cross pattern. For example, the right rear wheel is connected to the left front, and the left rear is connected to the right front.

Things are different on rear-wheel drive cars, where the contours are formed differently. So, one of the circuits works on the two front wheels, and the second on the rear wheels.

The GTZ is mounted on the housing of the vacuum amplifier. In this case, the working fluid is poured into a 2-section tank located above the main cylinder. The connection of the tank with the GTZ is ensured thanks to special holes.

To simplify maintenance, the walls of the tank were made of translucent plastic, which allows you to visually keep the level of the working fluid under control. As soon as the level drops below the normalized value, the sensor gives a signal to the control panel and the light comes on.

In the GTZ housing itself there are two pistons, which are mounted one after the other. The first has a free location, and the other, on the contrary, is fixed and touches the rod part of the vacuum amplifier.

In order to increase reliability, the pistons are sealed with rubber cuffs. The pistons are returned to their original position using special springs. By the way, they are the ones who hold the pistons in their original position.

As soon as you press the pedal, the vacuum booster is pressed in through the rod. Moving along the cylindrical cavity, the rod closes the hole for compensation. As a result, the pressure in the 1st circuit increases, driving the 2nd piston. The result is an increase in total pressure in the 2nd circuit.

At the moment the pistons move, empty areas are formed, which are filled with the working composition. Brake fluid is supplied through a special hole. The movement of the pistons is carried out until the return spring fulfills its functions.

GTZ disassembled

In each of the circuits, the pressure level increases to a maximum, which brings the mechanism into working condition. After the car stops and the pedal is released, the pistons return to their original position. In this case, the pressure level in the circuit is equalized and becomes similar to atmospheric pressure.

The missing air is drawn in through a special hole for compensation. When the piston moves in the opposite direction, the working fluid is squeezed back into the tank.

The advantage of a loop system is that if one loop fails, the other continues to perform its functions. For example, if there is a leak, it will manifest itself as a deeper “sink” of the pedal, but the brake performance will still remain at a high level.

Replacing the main brake cylinder on a VAZ 2114

The process of removing a faulty part is carried out in several stages. Having prepared the necessary tools and disconnected the battery terminal, you can begin dismantling the gas turbine unit:

1. Disconnect the wires going to the fluid level sensor in the tank.

2. Use a metal brush to clean the sensor contacts from oxides.
3. After removing the cap from the tank, use a medical syringe or bulb to remove the liquid.
4. Unscrew all the tubes and move them aside to gain access to the cylinder itself.

5. Armed with a key set to “17”, unscrew the nuts securing the GTZ to the vacuum booster and remove the cylinder body from the seat.

The process of assembling the structure and installing a new part should be carried out in reverse order.

Important ! Upon completion of the work, you should bleed the brake system and make sure that the fluid does not leave the reservoir.

If there are signs of system malfunction after replacing the turbocharger, you should make sure whether the front brake cylinders need to be replaced. Their condition can be checked visually by removing the wheel and checking the movement of the piston. Symptoms of worn pistons and their jamming appear as follows: the rolling of the car has noticeably worsened; the car pulls to the side when driving on a flat road; fast heating of the disk; smell of burnt pads.

Expert advice

1. 
   Before installing the parts, it is advisable to wipe them with alcohol and wipe them with a rag.

2. It is undesirable to allow parts to come into contact with fuels and lubricants, as they corrode the seals.
3. After replacing the turbocharger, it is imperative to bleed the hydraulic brakes, since without bleeding the system, air will remain in it, which will negatively affect the operation of the car.
4. If the O-rings are in good condition, they should still be replaced during removal.

Which brake cylinder should I choose?

Before starting work to replace a worn part, you should decide on the choice of replacement. In addition to the original GTZ, there are other analogue parts.

Most often, 2114 owners prefer to buy factory spare parts, so first let’s look at the advantages of parts from LADA:

• Reasonable price – about 1700 rubles;
• Good quality. The factory version of the GTZ runs for 70-100 thousand kilometers.

The disadvantage is the large number of fakes. We recommend purchasing parts in packaging.

When choosing which brake cylinder to choose for the VAZ 2114, you should consider the option from HOFER. The German analogue differs from the factory version in the quality of the material and lower price. The part number is HF 244102. The price of the spare part is about 1200-1400 rubles. Reviews from owners of cars with an installed HOFER GTZ do not highlight the disadvantages of the spare part, so the option can be safely considered for purchase. Replacing a part is easy, so any of the GTZ options can always be replaced with a factory one. The abundance of analogue spare parts for VAZ allows you to choose parts in different price segments. For stock fans, we recommend taking the factory version from LADA.

Diagnostics and repair

From the signs listed above, it is easy to understand that in most cases there is only one source of problems - rubber products that have become unusable. The cuffs crack and swell, as a result they leak liquid and close the discharge holes. Hence the recommendation: all “rubber bands” of the brake system should be changed at intervals of approximately 100 thousand km, without waiting for critical wear.

Reference. Many auto mechanics express the opinion that after replacing the cuffs, the main hydraulic cylinder will not last long. The statement is true if the car owner purchased cheap, low-quality spare parts or installed new o-rings in the cylinder, where internal wear has formed in the walls.

Before checking the GTZ for operability, make sure there are no other faults:

1. Inspect the wheel assemblies from the inside for leakage of brake fluid from the working cylinders.
2. Check the integrity of the expansion tank and the fluid level in it.
3. Start the engine and at idle speed, press the vacuum take-off pipe to the amplifier. If the engine speed has increased noticeably, there is an air leak and the master cylinder is most likely working.

A clear symptom indicating a breakdown of the main hydraulic cylinder is drops of brake fluid on the body . If you discover a leak, feel free to dismantle the unit and disassemble it to look for the cause. Another common problem - fluid flowing through the seals - is diagnosed as follows:

1. Open the cover of the expansion tank and place an assistant in the driver's seat.
2. Listening to sounds in the tank, give the command to an assistant to press the pedal.
3. If the pedal moves easily and gurgling is heard in the reservoir, liquid is entering there. The reason is that worn cuffs are unable to create pressure in the circuits; liquid seeps through the leaks and enters the container.

Also, problems with the GTZ are indicated by jamming or too little pedal travel. Sit behind the wheel, press it several times, and start the engine while holding the pedal with your foot. If it sinks to the floor or does not budge, disassemble the hydraulic cylinder.

Obvious symptoms

There are a number of specific signs that allow us to make a final conclusion that the master brake cylinder is faulty, and, therefore, begin diagnostics:

• Once the brake pedal is pressed, stopping occurs like a slow-motion movie. The reason is the loss of tightness of the piston cuffs. They can crack and “float”.
• Slowing down occurs only if you press the brakes hard. This is all due to swelling of the piston seals.
• The brake pedal has a short stroke. It is possible to block the passage between the already swollen seal. Due to the fact that the brake fluid does not find a way out, it is worth rechecking the compensation hole.
• Also, “cylinder disease” refers to situations when the brake is active at the end of the stroke. When the cuffs are completely worn out, fluid seeps behind the piston and the cylinder “re-bleeds.” The liquid goes straight into the expansion tank.
• The pads do not want to separate from the drums and brake discs, and heating is possible. A similar phenomenon occurs when the piston or bypass hole is malfunctioning. Often it's a matter of blockages.

BRAKE SYSTEM DEVICE

Like any other mechanism in your car, the brake system consists of several elements that work together. The VAZ brake system is no exception. It is much simpler both in structure and functionality than in popular foreign cars, but it also deserves attention.

Its main elements are:

• Front wheel brake structures;
• Pipelines (both sides);
• Hydraulic drive main cylinder;
• Tank;
• An amplifier that has a vacuum structure;
• Braking mechanisms located on the rear wheels;
• Two pressure control levers;
• The hydraulic system also has a regulator that controls the pressure;
• Pedal;
• Hoses made of flexible material.

The system is designed so that if one of the circuits fails, the second will provide safe braking. This is done in order to make driving as safe as possible. The brake system of the VAZ 2115 works on the same principle.

• Lever with locking button;
• Cable in a protective sheath;
• Adjustment nuts;
• Equalizer;
• Locknuts;
• Protective cover.

The weak point of the handbrake is the cable . It requires constant attention. Its stretching or rupture can lead to disastrous consequences. It is also worth remembering that the pads are constantly worn out (especially with active use). It is important to pay attention to the brake force regulator of the VAZ 2113.

Diagram of the brake system of a front-wheel drive VAZ car (device)

These are the elements that make up the brake system of the VAZ 2114. Everything is quite simple, both in repair and in preventive maintenance. Any adjustments are also made without much effort. For example, you can adjust the handbrake in half an hour yourself, and adjusting the brake pressure regulator of the VAZ 2114 will not cause stupor even for a beginner. These are the key features of the domestic automobile industry - everything is easy and simple.

The process of replacing the turbocharger and brake fluid

When the tools, new mechanism and fluid are prepared, you can begin dismantling the old VAZ 2114 spare part:

The first step is to disconnect the negative terminal from the battery. Replacing the master cylinder involves completely removing the old brake fluid - this is best done with a syringe;

Advice! When assembling the system, motorists often confuse brake pipes. To make your work easier, it is recommended to sign them with a marker. This applies to any parts in the VAZ 2114 car.

1. Once the threads have been removed, dismantling the main unit can begin. Using the “18” socket, you need to remove the nuts that attach the main cylinder to the amplifier;

The vacuum booster may also need to be replaced. In this case, remove the fitting and turn the main unit to the side. After this, you need to unscrew the hose and go into the interior of the VAZ 2114 car, where the pin locking bracket is located. After removing all the fasteners, you can install a new fluid pressure booster.