Expansion tank VAZ-2110: possible malfunctions and their elimination

2024 Author: Erin Ralphs | [email protected]. Last modified: 2024-02-19 11:42

The expansion tank is one of the components of the car engine cooling system. Its role is to ensure that the coolant can expand without consequences when heated, as well as to maintain its operating pressure.

Experiencing constant stress, the expansion tank may fail over time. We will talk about its malfunctions, as well as methods for their elimination in this article.

What is an expansion tank

Consider the design of the expansion tank VAZ-2110. Its factory case is made of translucent soft plastic. It has two holes on top: a filler neck and a seat for a refrigerant level sensor.

The expansion tank VAZ-2110 is equipped with three fittings to which the corresponding hoses are connected. The steam outlet pipes of the main and heating radiators are connected to the two upper "nipples". A thick filling hose is connected to the lower fitting. Here, in principle, is the whole construction.

Secret cover

The cover of the expansion tank VAZ-2110 is a separate element of the systemby chance. It is she who prevents the boiling of the coolant, maintaining the necessary pressure. The expansion tank VAZ-2110 is equipped with a lid, the design of which includes a double-sided spring-loaded valve. It opens and releases vapors when the pressure inside the tank reaches 1.1-1.5 kgf/cm². Its opening in the opposite direction occurs at 0.03-0.15 kgf/cm^{2 (when the motor is cooling).}

Why you need to maintain pressure in the system

Both antifreeze and antifreeze boil at normal (atmospheric) pressure when heated to 100 ⁰C. But as we have already said, in the cooling system, the working pressure is 1.1-1.5 kgf/cm². Under such conditions, the refrigerant will boil at least at 130 ^{0C. It is to ensure that the coolant does not overheat before the radiator fan turns on that a valve cover is needed. So if the expansion tank of the VAZ-2110 boils at normal engine temperature, you can be sure that it is exactly her fault. Naturally, if the coolant temperature sensor is working.}

What can happen to the cistern

The expansion tank VAZ-2110 is not particularly reliable, and therefore often presents the owners of these machines with unpleasant surprises. The most common malfunctions include:

• damage to the container itself;
• wear of threaded connections of the neck or seat of the refrigerant level sensor;
• lid failure.

Damage to tank capacity

The most common tank failure is its damage. First, microcracks appear on its body, and over time it simply bursts like a balloon. The reasons for this phenomenon can be: manufacturing defects, natural aging of plastic and increased pressure in the system. With marriage, everything is clear - you can buy a new device, install it on a car, and in a few days it will fail. All you can do here is go buy a new tank, cursing the manufacturer.

When it comes to aging plastic, there is no one to blame. The material cannot but lose its properties over time and under the influence of hot coolant. Increased pressure in the system occurs for one reason - a malfunction of the cover, or rather, its valve. We will talk about it in more detail a little later.

When the capacity of the tank is broken, do not try to restore it by gluing. It is better to buy a new device, especially since it costs very little. The price of a plastic tank on average does not exceed 200 rubles. There are, of course, more interesting proposals. Now on sale are expansion tanks VAZ-2110 made of aluminum. They will never leak or burst. True, such devices are not cheap - about 5,500 rubles.

Wear of threaded connections

If the lid of the device does not twist or twists, but does not provide complete tightness, you can try winding some kind of seal under it. This also applies to the thread with which it is attached.coolant level sensor. Naturally, such "tuning" can be considered as a temporary measure. In the future, the tank will need to be replaced.

Detecting a lid malfunction

Noticing that in your VAZ-2110 the expansion tank boils at normal engine temperature, check the cap first. This can be done using a car compressor with a pressure gauge.

First, disconnect one of the upper thin hoses from the tank. Its end is tightly closed by bending. This is necessary so that the coolant does not leak out when we create pressure in the reservoir. We connect the hose from the pump to the released fitting and start pumping. The lid must be tightly screwed on. When pressure reaches 1.1 kgf/cm² listen to the cork. She should begin to hiss, which indicates her performance. If, when the pressure reaches 1.8 kgf/cm^{2, the cover does not begin to bleed air, you can safely throw it away. Otherwise, the tank will burst soon.}

If the lid, on the contrary, began to let air through before it was supposed to, throw it away. If the expansion tank in your VAZ-2110 is boiling, it is the reason.

Dismantling and replacing the tank on the "top ten"

To replace the device, you will need to drain the coolant if it has not flowed out before. The expansion tank VAZ-2110 is dismantled as follows:

1. Disconnect the negative cable from the battery.
2. Disconnect the wire from the refrigerant level sensor.
3. Use a Phillips screwdriver to unscrew the screws on the clamps of all hoses, loosening them.
4. Disconnect all hoses going to the tank.
5. Unfasten the rubber tank fastening strap and remove it.

Installing a new device is done in reverse order. Don't forget to add coolant to the correct level!

Some useful tips

To prevent an expansion tank malfunction from taking you by surprise, follow these guidelines:

• Constantly pay attention to the readings of the coolant temperature sensor. If you find that the permissible indicators are exceeded, immediately go for diagnostics or check the tank’s performance yourself.
• At least once a month, inspect the expansion tank when the engine is hot for damage.
• Keep an eye on the refrigerant level. If you find it has fallen, find and fix the cause of the leak.
• When the coolant boils in the tank, do not continue driving in any case - this will damage the engine.
• If you are going to replace the tank, buy products from trusted manufacturers in specialized stores.