Like any engine, the car motor during work is heated, so it is necessary to constantly cool it. To do this, a cooling system is provided in the car's design. According to the principle of operation, they are two types: air and liquid. Liquid gained the greatest distribution, although they are more complex constructively. Air systems with their simplicity are much more prone to overheating.

Since all the motors are currently functioning with liquid cooling, a small plastic container with a lid is located in the motor compartment of any car, which is designed to fill antifreeze. It is called an expansion tank. In different engines, the expansion tank volume varies within 1.5-8 liters. About this further in the article.

Expansion tank of the car, where installed, why need

Why do you need an expansion tank? The bottom line is that any fluids during heating are increased in volume. Thus, when water is heated to 100 degrees Celsius, its volume will increase by 4.5%, toosol and antifreeze - up to 6%. So that the coolant does not splash out when heated from the system, an expansion tank is required, which is a kind of compensator or buffer.

In the last century, there were no expansion tanks under the hood, since ordinary water was used as a coolant, and the top tank of the radiator was applied as a compensator, which was not taped under the string. When the cooling fluids based on ethylene glycol appeared, that is, antifreeze, which have a greater extension coefficient than the water, additional expansion tanks appeared so that the radiator does not have to increase.

Thus, the expansion tank (hereinafter referred to as RB) is designed to compensate for the volume extension of the coolant with an increase in its temperature. Located RB in the engine compartment so that the fluid level is approximately in the middle of the height of the tank. In this case, fluids in the tank and the radiator are at one level. Since the RB is above the radiator, the role of the filler neck is played by the RB cover.

How does a car expansion tank running

The expansion tank of the lid, polypropylene housing and two nozzles for connecting the hoses of the liquid system. With the help of the lower hose, the device is connected to the cooling line, and the top will take the pair and air bubbles from the system. At modern models, float sensors of the coolant levels are not rarely mounted.

For this option, the RB is equipped with another throat, which is designed to mount the sensor. On the side of the tank are control risks: from the bottom min and to the top MAX. In this interval, there must be a level of coolant.

To understand how the device works, consider the temperature modes of the functioning of modern engines. As you can see, the motors are functioning in critical temperatures.

To raise the bar, the permissible temperature constructors increase the pressure in the coolant, due to which its booster temperature increases. For this, the system is sealed, and maintain overpressure in it. For different motors, this value varies in the range of 0.1-0.5 bar.

At the same time, a substantial vacuum in the free space of the expansion tank is unacceptable, since the air suits will occur in the system, which will lead to air traffic jams, which make it difficult to circulate the coolant and can lead to overheating. The pressure of the coolant supports a special regulator, which is in the filling lid.

In addition to protective function, the cover of the Republic of Belarus still performs the task of the pressure regulator. For this, two valves are collected in the lid: vacuum and safety. The latter is a rubber spring-loaded diaphragm, pressed outside and triggered when the pressure will exceed the spring force. Vacuum consists of rubber washers with a small spring, which is installed inside a large.

Expansion car car: causes of a plastic expansion tank breakdown

During operation, the car and its individual components acquire different defects. The Republic of Belarus is also susceptible to breakdowns, which lead to its depressurization with further leakage of the coolant as a result of such reasons:

• Strokes and other mechanical exposures.
• Long stay in boiling antifreeze tank.
• Plastic, from which the container is made, has an insufficient thickness, which leads to cracking of the walls.
• Increase pressure in the cooling system.

If you occur, you need to determine the location of the leakage and perform the repair of the expansion tank.

Ways to eliminate cracks of expansion plastic tanks

During the operation of the tank plastic undergoes multiple deformations: expansion and narrowing due to temperature differences. Functioning in conditions of limit pressure and temperature values \u200b\u200bentails cracking material.

Plastic, which is used in the manufacture of RB, is not able to join the reaction with glue of any brand, which is why it is impossible to perform high-quality gluing. The most widespread use of motorists have found such solvication of cracks:

• Plug the places of depressurization with special sealant, cold welding, epoxy resin.
• Seet the gaps in the RB housing using the reinforcement metal grid.

Epoxy resin and cold welding are used to close the gaps in the tank for a short time, for example, to get to a hundred or garage.

Tools, fixtures, consumables

To dismantle RB, materials and tools will be required:

1. Capacity for fusion of coolant.
2. Set of wrenches.
3. Screwdriver.

Dismantling of the expansion tank of the car (step by step)

Order of work:

1. First of all, loosen the fasteners that hold the plastic container.
2. Drain Oh
3. Disconnect the hoses and nozzles
4. Remove the tank.
5. Watch a problem space on the housing.

How to pour a crack in a plastic tank (in detail)

Order of work:

1. With the help of a napkin, carefully clean the plastic in the fracture site from the residues of the toosol.
2. Decrease the place of welding with acetone or solvent, dry.
3. Cut the brass mesh strip, which consists of small cells, the length of damage.
4. Take a mesh pay on the embedded junction.
5. Evenly solder the grid to the edges of the joint so that the reinforced layer is formed throughout the grid area.
6. We carry out the grinding of the seam.
7. We apply a putty, primer and perform staining.

What sealant can be eliminated to flow in a plastic tank

For soldering, a soldering iron is used with a power of at least 40 W. In the absence of a metal mesh and soldering iron, the masters are used to repair the body of the tank, a special red polyathhese sealant for plastic DONEAL.

This agent has high heat resistance and resistance to the effects of oil liquids. Before applying a polyathizing in place of the defect, you need to perform thorough operations on stripping and degreasing, as well as removing traces of substances used earlier.

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