If the VAZ 2107 boils: what are the reasons and how to eliminate them

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For what reasons does the VAZ 2107 boil, or more precisely, the liquid in the engine cooling system? We will try to figure this out by explaining everything as simply as possible. The cooling system is the most “nasty” part of the car.

It can cause a lot of trouble for a motorist. And sometimes getting rid of shortcomings turns out to be very difficult. And very often it happens that the antifreeze is thrown out of the tank, or it simply boils, while the needle inexorably strives at the speed of a marathon runner towards the red zone.

Why is this happening? On old cars, for example, very often when replacing one component it turns out that it is necessary to go through almost the entire system. And if the engine boils, then it is quite possible that significant repairs will have to be carried out. But if this happened in a traffic jam on a hot summer day, then most likely there is a malfunction in the electric fan or its activation sensor.

For example, the thermostat is broken. We started removing it and discovered that the pipes had become unusable. And along with them, the clamps. And these are just flowers, because it is unknown what is going on inside.

It is quite possible that the antifreeze is boiling because something is hindering its movement. For example, a large amount of deposits on the walls of the cylinder block. And now in more detail about what could be the reasons why antifreeze boils.

Pump drive problem!

A (with a force of 10 kgf) = 10..15 mm;
B (at the same force) = 12..17 mm The circulation of coolant in the system directly depends on the water pump. The higher its performance, the better the cooling process. To improve performance, they use “tuned” pumps with a larger number of blades on the impeller.

This is reasonable and correct, especially in cases where the engine has been modified and improved. And if the tuned engine does not boil when working with the original cooling system, then this is something out of the ordinary.

If you open the hood of a VAZ 2107, you will definitely see one feature - the liquid pump and generator are driven by one belt. Hence the conclusion - if it breaks or weakens, then the antifreeze moves through all channels at a lower speed, cooling worsens significantly.

The way out of this situation is to replace the belt or tighten it. On a VAZ 2107 car, like on most others, this is done in literally two movements. And with this we are just beginning to consider the reasons why the engine began to boil. Further more interesting.

Air conditioner

I would also like to mention when the engine gets hot when the air conditioning is turned on. The situation with the air conditioner is ambiguous. The increase in load on the engine has already been taken into account by the factory, but if it is in poor condition and the cooling system is faulty, this is still possible.

Dirty air conditioner radiator

The second reason related to air conditioning is dirty radiators. The air conditioning radiator is installed in front of the cooling radiator and in hot weather, if heat is not removed from it well, it heats up itself, and a “dirty” main one leads to overheating of the engine.

Is the problem in the expansion tank?

There may also be a malfunction in it. Please note a few points:

Are there any cracks in the tank?
Does the cork allow air to pass freely?
Are the clamps tightened securely?
Is the fluid level within acceptable limits?

Only by answering all these questions will it be possible to talk about whether there are any defects in the expansion tank. If there are cracks in it, then antifreeze will leak through them. These are the reasons for the rise in temperature. Injector or carburetor - it doesn’t matter, the expansion tank must be in perfect condition.

The consequence is that you constantly need to top it up, as the level in the expansion tank will begin to drop. A drop in level is the first step towards overheating. Try to keep it between O and MIN.

In this case, only the antifreeze will circulate normally through the system. The reasons for boiling often lie in the little things. For example, the engine boiled after the driver failed to monitor the antifreeze level.

Radiator fan

As you understand, the engine operates in a variety of modes. Sometimes he pulls the car along the highway at high speed, and sometimes through a traffic jam. And in the latter case, the speed is lower than that of pedestrians.

What's the difference? And the fact is that the radiator on a VAZ 2107 car is blown in these two modes with different amounts of air. In the first case, the flow is enough to maintain the temperature balance, but in the second it is not enough. And it doesn’t matter whether it’s an injector or a carburetor, the radiator must be blown normally.

You have to create an artificial flow using an electric fan. In earlier VAZ 2107 cars (and indeed in the “classic” series) impellers were used that were mounted on the axis of the liquid pump. With the help of these mechanisms, the radiator is subjected to airflow. An electric fan may not perform its functions for the following reasons:

The impeller has been destroyed.
The sensor responsible for turning on the fan has failed.
The motor winding burned out.
Destruction of electrical wiring (breakage, contact failure, oxidation).
Failure of a relay, fuse, button (if these elements are present in the design).

The last point applies mostly to VAZ 2107 cars, in which the fan switching circuit has been modified by installing a button in the passenger compartment. With its help, the driver can forcefully start the fan.

If it doesn’t start even from the button, you need to find out the reasons. To do this, connect the wires from the fan to the battery terminals. If it doesn’t work, the motor winding is damaged.

Please note: for better airflow, use a diffuser! This is a small plastic element that will force more air to flow to the radiator. And if there are no breakdowns in the fan, then be sure to install a diffuser, the radiator will thank you.

What to do?

Some useful tips:

any increase in temperature will indicate a decrease in the efficiency of the antifreeze supply devices - here it is important to be able to properly cool the installation;
the simplest solution to lower the temperature is to turn on the cabin stove at full power;
If a low level of anti-freeze is detected, it needs to be replenished - this is only allowed when the engine has cooled down.

First of all, the engine’s ability to overheat is indicated by the temperature arrow on the instrument panel approaching or moving into the red zone.

Temperature gauge on the dashboard

If the refrigerant temperature rises, the owner needs to act quickly. First of all, you need to stop the car. Then turn on the heater to maximum, which will make it possible to remove some of the engine heat into the cabin. Next, let the engine idle for a few minutes, then turn it off.

However, such instructions are not always useful - especially if smoke is constantly pouring out from under the hood and the stove is blowing cold air. Here you will have to dismantle the thermoelement. You can drive like this, but you shouldn’t delay with qualified repairs. In the cold season, the absence of a part will not allow the engine to warm up to operating standards.

On the other hand, temperature fluctuations are also observed. It can change while idle in summer in traffic jams and when traveling at low speeds.

Normally, a fan should handle the increased heat. Therefore, the scale needle will first rise, and then, after turning on the cooler blades, it will automatically fall again.

It's a traffic jam!

The cooling systems used in the eighth VAZ family and higher use a slightly different design. The formation of traffic jams is almost impossible (but possible). But in a VAZ 2107, an air plug can appear at any time. And there can be a lot of reasons for this, but most often it is a violation of the tightness of the system.

Carefully inspect all pipes for cracks and damage. Using a socket on “6” or “8”, check the tightness of all clamps. After this, inspect the radiators (including the one used in the heater) to see if there is damage to the cells. If the antifreeze is thrown out of the tank, then you have the most unpleasant breakdown; we will talk about it a little later.

Bleeding the system

On VAZ 2107 cars and its analogues (models 2101-2106), you can remove the traffic jam very simply. It is enough to remove the pipe that goes to the carburetor to heat the damper. If an injector is installed, then remove the pipe going to the throttle assembly.

Then fill the radiator with antifreeze. And do not forget that the stove tap must be opened. When it is full, you need to squeeze all the pipes with your hands (or rather, the top and bottom). The antifreeze should go away.

Add the missing amount and start the engine. Warm it up and carefully monitor the level, sometimes add antifreeze. You will have to add about three liters. And watch when fluid comes out of the tube connected to the carburetor.

When this happens, you need to put it in place and tighten the clamp. Of course, if you stop there, you won’t be able to get rid of the breakdown. The antifreeze still boils, the temperature rises. And why does this happen? Do a few more procedures and everything will return to normal.

Put on a glove and continue to slowly crimp the pipes. In this case, you need to install a plug on the radiator, and there should be antifreeze in the expansion tank between the two marks. That's all, there is no air, circulation occurs normally.

One small piece of advice: when refueling the system, it is advisable to position the car so that its front is higher than its rear. This will ensure that the system is completely filled. As a result, the antifreeze does not bubble or boil, the car runs like a watch.

The thermostat is the boss

Not a very pleasant breakdown, especially if it happens on the road. And if the engine is boiling due to a faulty thermostat, then there is only one way out - to change this element of the system. True, at first you can slightly “reanimate” him; for this you need to apply several sharp blows to his body with something heavy.

But such a “rough” solution may not always help. There will be much more trouble if liquid leaks out of the tank. The thermostat allows the system to switch the circulation of liquid between two circles - large and small. These circles differ in that in the first one a radiator is connected to the cooling process. And if it does not connect, then the liquid boils.

On VAZ 2107 cars, and indeed on all cars of this manufacturer, the thermostat fails in such a way that the antifreeze continues to circulate in a small circle. And even if you turn on the radiator fan with the button, this will not save the situation.

The car still drives poorly, the antifreeze boils, and you won’t be able to immediately understand why this is happening. And the answer is very simple - to increase the life of the thermostat, do not pour running water into the system. Use any antifreeze, in particular antifreeze. The water leaves a large amount of scale, which interferes with the movement of the thermostat element.

If the VAZ 2107 boils: what are the reasons and how to eliminate them

More serious damage

A car is an expensive pleasure and any breakdown costs a pretty penny.

Among the “expensive” breakdowns of the cooling system are the following:

Radiator clogged.
Destruction of the head gasket.

Moreover, the second reason turns out to be more significant, much worse when liquid is thrown out of the tank. Although a clogged radiator is difficult to clean properly. But if you arm yourself with the experience of US police officers, you will find a way out.

Pour black carbonated water into it (we won’t advertise), let it sit for a while. And that's it, the insides are perfectly clean. Or you can simply replace the radiator. It’s much worse if you start to notice that the liquid is bubbling in the expansion tank.

This is a clear sign that there is a breakdown somewhere in the gasket. It needs to be changed immediately to prevent this breakdown from progressing. Otherwise, repairs can cost a pretty penny.

But why does the liquid bubble? Look carefully at the operation of the engine in this mode. Antifreeze seeps into the cylinder through the crack. And it can get into both the lubrication system and the combustion chambers. Symptoms:

Presence of white smoke from the exhaust pipe.
Traces of antifreeze in the oil, an increase in the level.

That's the whole problem, it's outrageously simple. The antifreeze is seething, boiling, the temperature is constantly rising. And this causes a lot of problems. The liquid boils due to the formation of air pockets. But it bubbles because air under high pressure enters the cooling system from the combustion chamber. There is only one way out - replace the gasket. And if liquid is thrown into the tank under strong pressure, you immediately need to blame the cylinder head gasket.

What not to do when the engine is boiling

When the engine is boiling, the following actions on the part of the driver are strictly prohibited:

increase engine speed, increasing the load on the internal combustion engine;
stopping the car abruptly - it is better to turn on the interior heater to maximum heating;
dilute the boiling liquid with cold water or antifreeze - this will easily lead to damage to the cylinder block, especially cast iron;
check the condition of the antifreeze on a hot engine - it is important to allow time to cool, otherwise the boiling liquid may get on the skin and lead to severe burns;
leave the car hood closed - after turning off the ignition, you must immediately lift the lid, ensuring a flow of fresh air to the engine;
pour cold water on the motor - a sharp temperature change can cause cracks and breakages of the BC.

Experienced motorists begin diagnostics right on the spot. They competently check the pipes, pump, thermostat, and cooling fan.

Checking the cooling system pipes

If there is not enough experience for such actions, the car should be taken to the nearest service center. Highly qualified technicians and the availability of stationary equipment will allow them to quickly and correctly determine the cause of boiling. The problem is always fixed on the spot, following diagnosis.