What is the pressure in the engine cooling system?

During operation, the internal combustion engine is heated to a high temperature. With the heat removal function, the cooling system of the motor must be controlled. This is necessary for efficient operation of the power unit. If there is no circulation of the coolant, then the internal combustion engine will overheat very quickly, with all the ensuing consequences. Let's talk about what should be the pressure in the cooling system and how to eliminate typical faults on their own.

Briefly about the main

The first thing to do is to decide what is the pressure in the cooling system. It would seem that the banal circulation of the coolant should be sufficient to remove heat. It used to be so when water was poured into the radiator. But it was also the norm to meet on the roadside a car, from under the hood of which the steam is pouring. This was due to the fact that the water did not have time to cool, and since the temperature of its boiling is equal to 100 degrees, it quickly boiled.

Modern antifreezes, most of which are made on an alcohol basis, boil at about 115 degrees Celsius. But it is worth remembering the school course of physics, where you can find out that an increase in pressure leads to a shift in the boiling point of the liquid. This also applies to antifreeze, which circulates through the ICE systems.

What is the norm in the engine cooling system?

Here much depends on the design features of the car. But usually it is 1.2-1.4 atm. For cars. For example, on the VAZ-2110 a normal indicator can be considered 1,2 atmosphere. The critical pressure in the system is reached when the antifreeze is heated and its boiling point is reached. At this time, the pressure in the system must be reset. This is done so that the radiator or any other weak point does not break.

For pressure relief, the expansion tank cap is responsible. Its device is extremely simple. There is a metal case with two holes. Inside is a ball of diameter larger than the holes. When a certain temperature is reached, it rises. This leads to the fact that air is vented into the atmosphere. On many cars 1,5 atm. Is the pressure at which the reset occurs.

Check Valve Performance

While the antifreeze has not heated up, the ball inside the lid closes the bottom hole, while the upper one remains open. It is necessary for the influx of air from the atmosphere and rapid warming up of the coolant. I would like to note that periodically it is necessary to check the operability of the cover. After all, it often happens that she podklinivaet in one of the provisions. Because of this, the engine either warms up for a long time or pressure does not hold.

Checking the cover of the VAZ-2110 expansion tank is very simple. For this, it is enough to unscrew it and shake it. If you hear how the ball dangles inside the case, then the system works and it does not jam. Excessive pressure in the engine cooling system, as already noted above, can lead to fatal consequences. Therefore, on modern cars, the lid has two valves: intake and exhaust. Now on sale you can find covers that work at a certain pressure. But it is strongly recommended not to change the parameters laid down by the manufacturer.

Increased pressure and methods of struggle

The cooling system is arranged in such a way that the expansion tank cap is responsible for the pressure in it. Although there are different designs. For example, on some American cars, the expansion tank serves as a settler, and the lid itself is installed on the radiator tee. Nevertheless, the essence of the work remains the same.

The pressure in the VAZ-2110 engine cooling system should be in the range from 1.2 to 1.5 atm, while the fall or excess of these indicators can already be considered a serious deviation. Quite often, motorists are faced with increased pressure. The cause will be the same cover, the valve of which stuck in the closed position. In this case, the system will warm up, the pressure will increase, and its reset will not occur. Because of this, steam-air plugs are formed, which prevent normal circulation of the coolant through the system.

Replacement of a failed node

The cover of the cooling system can serve more than the engine of the car, and you can buy a new one that will be defective. Guessing is difficult here. But in any case, do not try to repair it. It is worth it for most penny models and is non-repairable. In case of a malfunction, it is simply changed to a new one.

In this case, it is strongly recommended not to shorten the springs, changing the moment of operation of the cover. After all, many motorists do this, which in most cases does not lead to anything good. Of course, if you tuned the cooling system and the engine, it is possible that you need to achieve greater pressure in the system or, conversely, less. In other cases, it is worth buying only the original or a decent analog with the same parameters. Remember that a lot of pressure in the engine cooling system can lead to local overheating of the ICE and the failure of certain nodes.

Leakage of the system

An even more popular problem in the circle of motorists is the lack of pressure. This can happen because of:

• The jammed air valve;
• The presence of leaks in the cooling system.

Accordingly, to identify the problem will not be difficult. The first thing you can look at the level of antifreeze on a cold engine. If it does not change from trip to trip, then there are no leaks in the system. The second point is to change the air valve to a new one. After that, the pressure should be normalized, and the antifreeze will not overheat. Very often high pressure in the engine cooling system leads to the fact that it then falls. This is due partly to the wedge valve. He then works, then no. As a result, the pressure is pumped, which can lead to leakage at a weak point, and then leakage disappears.

How to find a leak?

To begin with, it's worth starting with a visual inspection. It is worth a look under the car, it is likely that under it a pool of antifreeze. But even here one must understand that often a breach is manifested only when a certain pressure is reached, so it will not be possible to find it on a cold one. Nevertheless, there are special devices for pressurizing the system, and the engine must be cold to avoid burns.

Such a device can be a conventional pump and a manometer. Everything can be done in garage conditions. First of all, detach the upper branch pipe, which is suitable for the expansion tank. It is desirable to insert a suitable diameter bolt in the hole. Next we connect a pump with a pressure gauge to the branch pipe and pressurize it. When reaching 1.5 atm. The air valve must be activated. At the same time, we are looking for a leak.

Nuances of the cooling system

Much also depends on the coolant used. To fill up water, for example, is not necessary even in old cars, it is better to buy an inexpensive antifreeze, there will be fewer problems. Nevertheless, modern engines require high-quality cooling. The manufacturer in the manual indicates the recommended brands of coolant. It is advisable to adhere to these tips and do not dilute the antifreeze if you do not have a concentrate.

Modern cooling fluids have different service life and boiling point. For example, G12 boils later than G11, and G12 ++ has an increased resource, but it also costs more. In any case, in order to avoid boiling of the engine, it is recommended to fill only with a high quality coolant.

Original spare parts

Very often the high pressure in the engine cooling system is formed due to the malfunction of the air valve, we have already dealt with this. Another thing is that this valve has insufficient resource, or even a new one may turn out to be non-working. This applies to other elements of the cooling system, such as a thermostat, a water pump, nozzles, sensors, radiators, etc. To sleep peacefully, it is better to acquire an original, the life of which is often quite large. Of course, such spare parts are much more expensive, but they almost 100% guarantee the functioning of the site as a whole. Indeed, the failure of such an insignificant element as a lid can cause a major overhaul of the engine.

As for the Chinese components, this is a lottery. Some of them can be quite high quality, while others do not go 100 kilometers. It is better not to take risks, because the miser pays twice.

Serious consequences

We have already considered that in the engine cooling system pressure is created. It's quite normal. Another thing is that very often there is a malfunction, which is extremely difficult to determine. For example, antifreeze leaves, but there is no visible leak. In this case, it is possible that the coolant gets into the crankcase of the engine. It is recommended to check the oil level regularly. If the coolant really goes into the motor, the level will rise. Most likely, it says about the broken cylinder head gasket, which is equivalent to the bulkhead of the power unit.

Every detail has its own specific resource, when it is reached, there is no guarantee that it will continue to function properly. There are often cases when even the new cover of the surge tank turns out to be inoperative. And it's not about the Chinese part, but about the original one. Unfortunately, this can not be avoided.

Let's sum up the results

So we figured out why pressure in the engine cooling system, why it can be excessively high or, conversely, low. In self-checking, there is often nothing complicated, although much depends on the car. For example, it happens, the coolant temperature sensor goes out of action. He can give incorrect data to control devices, thereby misleading the driver. It can show both the high temperature of the power unit, and, conversely, low. But this will not say that the system is working incorrectly.

With any breakage in the cooling system, they must be eliminated as soon as possible. It is advisable not to operate the car with a jammed cover or thermostat. After all, for some engines, overheating is deadly, and major repairs are quite expensive. In general, it is worthwhile to regularly check the level of coolant in the system, make sure that there are no leaks and other defects. It is also recommended to periodically clean the radiators of dirt, as this may cause an increased engine temperature.