What compression should be in a VAZ 2110. Different compression in the cylinders: what to do and can you fix it yourself? VAZ engine compression

What is compression of the VAZ 2110, what working function does the compressor perform, what is the principle of its operation? Why does this device fail and what can be done in this case? Any car owner should know the answers to these questions.

Compression is the maximum amount of cylinder pressure resulting from the completion of the compression process. This value is measured in several ways. The most common unit of measurement is the atmosphere. Compression is not a constant value; it changes depending on the compression force, and also becomes less as parts wear. In addition, it may be different for different engine models and depends on the size of the power plant.

Every driver has probably heard about compression at least once, but it is often confused with another value, namely compression force. It’s worth saying right away that these are completely different things. Compression ratio determines the pressure throughout the entire compression period, while compression only determines the pressure at the end of the stroke.

Compression problems

Most common problem compression of the VAZ 2110 is a sharp drop in pressure. As a result, the engine refuses to work and parts wear out. Why does this happen? This happens due to a careless attitude towards the car, when filling with low-quality fuel and oil.

Poor fuel affects the deposition of salt residues, which, when the engine operates intensively, cause damage to parts, chips and scratches, leading to problems and malfunctions of the working system. To increase compression and restore normal operation of the power unit, you must first eliminate the problems that caused the failure, that is, carefully diagnose the system and replace defective parts.

As a rule, VAZ compression decreases due to piston wear. This means you need to pay attention to the condition of these parts. Wear of the piston system occurs due to the loose fit of its elements. This is a manufacturing defect that is rarely found in modern European cars, but is normal in domestic cars, especially the VAZ 2110.

What can be done in this case? It is necessary to purchase appropriate additives designed specifically for these purposes and increase the non-docking part to the required dimensions. Sometimes, with minor joining defects, thick motor oil helps.

But there is another problem, namely the occurrence of piston rings. Then the use of thick motor oil and increasing thickness due to additives is unacceptable; it is necessary to carry out comprehensive repairs to correct the problem. It also happens that the pistons jam. To resolve this problem and get the device working properly, you need to remove the spark plugs and add a little (about 100 ml) of engine oil.

The candles are set aside for an hour and put in place. Now you should let the engine run. What will happen? In an hour, the oil softened the scale on the spark plugs, and now (when starting the engine) it will easily be used up and will not slagging a part that is vital for the car. This means that the compressor on the VAZ will begin to operate in normal mode.

How to install a compressor with your own hands?

When the old device is faulty, you need to install a new one (see photo). The installation of a compressor on a VAZ is carried out in a short period. This is not a labor-intensive process, but requires extreme care and caution. To work you will have to equip yourself with the following equipment:

• set for compressor installation;
• keys;

Compressor installation diagram

• air filter system;
• pressure controller;
• paste based on abrasive components.

Before starting work, you should make sure that power unit completely cool, otherwise you may get burned. The work begins with dismantling the air duct and filter. The manifold clamps are removed. Now the fasteners of the part, which is popularly called a snail, are installed on the motor block.

We replace the drive belt with a belt taken from the compressor unit kit. It is more efficient, reliable and will last much longer. We adjust the belt so that it is not too tight, but not too loose. The next stage is the installation of the air duct and fastening of the pressure controller.

A filter is attached to the compressor outlet. The last stage of the work is to adjust the injector so that the power unit does not receive a lean mixture. It’s better to check this at a service center, since doing this operation yourself is problematic.

This is the entire list of work to replace the compressor. It may seem too complicated for a beginner, but in fact there is nothing difficult here. You should carry out the described work 1-2 times in the presence of a knowledgeable master, and this skill will be practiced to an automatic level.

The pressure created in the engine cylinders is otherwise called compression. If its level in the cylinder is too low, a large volume is occupied by the fuel-air mixture, which has a low concentration, which leads to slow ignition.
At the same time, heat transfer increases and the engine overheats. If the compression level is very high, rapid ignition of the fuel-air mixture occurs, due to the high concentration, detonation or explosion of the mixture occurs.
At this time, the engine experiences increased pressure, which has a destructive effect on its parts. There are situations when the compression in the cylinders on a VAZ 2110 is different.
In this case, ignition occurs faster in one cylinder, slower in the other, and the engine begins to operate unevenly. An imbalance is created in the operation of the pistons and shafts, which has a negative impact on their condition.

How to control compression in the cylinders of a VAZ 2110

Each method helps to more accurately determine node defects.Compression is most often measured with the throttles in the carburetor closed and open.
When the valve is fully open after measuring compression, the following defects can be detected:

• The presence of scoring or serious damage to the cylinder surface.
• No burnouts or valve deformations.
• Rings stuck or coked in the piston grooves.
• Piston failures or burnouts.

With the throttle closed, after measuring the compression, the following is determined:

• Is there a stuck valve? If the design has a hydraulic tappet, the presence of defects in the camshaft cam profile is determined.
• Seat valve fit.

The compression of the cylinders of a VAZ 2110, a car without a hydraulic compensator (see), is measured with the dampers open.

Compression measurement

In order to avoid negative consequences, from the compression deviation in the cylinders, it needs to be measured. To carry out DIY work, a device called a compression meter is used.
Its price is small, relative to the funds that will be spent on engine repairs when a cylinder needs to be replaced in a VAZ 2110.
So:

• When choosing a device, you need to pay attention to the limit switch. It connects to the engine and can be rubber or threaded.

Tip: Preference should be given to an end cap with a thread. It is more convenient to work with it and you can do it without outside help.

• The engine is warming up.
• Everything is unscrewed and removed.

Tip: It is better to measure compression when the engine is warm, with a well-charged battery so that it provides rated power to the starter.

• The wires are disconnected from the ignition coils.
• The fuel pump turns off (see). With a mechanical device, you can disconnect the hoses supplying fuel or shut off its supply.
  With an electric fuel pump, the fuse is removed or the relay is turned off to stop the power supply.
• A compression gauge is connected to one of the cylinders, as shown in the photo.

• The starter is turned on, which cranks the engine crankshaft until the highest pressure is set. The crankshaft rotation speed should be between 200 rpm and 350 rpm.

Advice: Special attention need to pay attention to the position throttle valve, it should be completely open.

• The maximum reading of the device will correspond to the compression level in the cylinder.
• This is how compression is measured in the cylinders of a VAZ 21102, one by one in each cylinder. Details of the work can be seen in the video.
• The instructions indicate that the pressure in different cylinders should not differ by more than 0.1 MPa and its nominal value should be below 1.0 MPa.
• If on a VAZ 2110 there is no compression in one cylinder or it is low, this may indicate a loose fit in the valve seats, damage to the gasket, burning or breakage piston rings.
• To find out the reasons, you need to fill the cylinder in which the compression is low with approximately 20 cm2 of engine oil, and then measure the compression.

If the compression meter readings increase, it is most likely faulty. Maintaining compression values ​​indicates a loose fit of the valve plates to the seats or damage cylinder head gaskets.

Tip: You can find out the cause of insufficient compression by pumping compressed air into the cylinder. In this case, the piston must be installed in top dead compression stroke point.
To do this, remove the tip from the compression gauge and connect the compressor hose to it. The tip is inserted into the spark plug hole and air is supplied to the cylinder under a pressure of 0.3 MPa.
At that time crankshaft should not turn, it is fixed hand brake. Leakage of the intake valve is indicated by air leaking through the throttle assembly, and the exhaust valve is indicated by air leaking through the muffler.
Damage to the gasket is indicated by air escaping through the neck to expansion tank or into an adjacent cylinder, which is indicated by a characteristic hissing sound.

Compression is very important indicator for diagnosing engine parts without disassembling it. Based on the difference in values ​​found in different cylinders and its average, you can quite accurately determine how worn out the connecting rod and piston group of the engine is, and identify breakdowns in this group and parts in the valve mechanism.

For some reason, many car owners confuse concepts such as compression and compression ratio. However, despite their similarity, they are not one and the same. This is approximately the same as the angle of the closed state of the contacts and the ignition timing angle. It is enough to note that the compression ratio is a geometric value, expressed in absolute units (in other words, it is simply data that is not measured in any units), they are actually unchanged for engines of the same model, if they have not been modified, but are in standard configuration. Compression, in turn, is measured in pressure units (bar, MPa, atmospheres), its readings are very dependent on the measurement method and the technical condition of the car. At the moment we will tell you about what the compression of the VAZ 2110 engine is.

Compression is a physical quantity that determines the pressure that is created in the cylinder at the end of the compression stroke. It is measured in kg/cm2 or atmospheres; less often you can find measurements in kilopascals, bars and other units. As wear occurs, compression can vary greatly. It may depend on the compression ratio (good engine compression can be considered to be approximately the calculated value by multiplying the compression ratio by 1.5 atm - this is due to the effect of adiabatic compression). As a result, the corresponding compression values ​​for a standard VAZ 2110 engine will be approximately 7-9 atmospheres. (If the engine is forced, the compression may change to 11-13 atm.).

The meaning of compression is the technical condition of the engine and the entire machine as a whole, along with oil pressure. The higher the compression level, the fewer gases will break into the engine crankcase and, as follows, more gases will do useful work, and at the same time the power will also increase. Oil consumption, throttle response, engine stability, engine start-up speed, fuel consumption will all depend on the compression level. In addition to all this, the compression value can be affected by the state of the electrical equipment (battery, starter, connecting wires) when measuring it.

When compression drops in any of the VAZ 2110 cylinders (maybe this happens in all cylinders at once) or compression levels are different in all cylinders, the engine will need to be repaired. Often the main reason for a drop in compression is worn out piston rings, for example, after overheating. In second place are valves. Then a breakdown of the cylinder head gasket. There may also be exotic conditions, such as a piston pin that has come out, or a burnt piston that has “milled” the liner. In order to find the cause of the drop and imbalance of compression, oil is poured into the cylinder, after which the compression is determined again. If at the same time it increases significantly, then the rings are almost always to blame. If not, the problem is most likely in the valves or head.

The main significant problems that low compression causes are a drop in power, a decrease in top speed, deterioration in acceleration dynamics, and an increase in the amount of fuel and oil absorbed - sometimes this is very noticeable.

To measure the compression of a VAZ 2110 you need to use a special device - a compression meter, which looks like an ordinary pressure gauge, with which the tire pressure will be measured. This device has a special adapter that needs to be screwed into the candles, or simply pressed tightly against the hole with a rubber ring. The adapter has a nipple or spool that allows you to save the instrument readings for comfortable reading. Such compression meters can be purchased at any auto market.

Compression is often determined in two ways: advanced - with closed valves in the carburetor, very ordinary - with open valves. To obtain clearer results, professional mechanics measure compression using 2 proposed methods. At the same time, they do not even unscrew the spark plugs in other cylinders, taking measurements on a cool engine, with the carburetor valves open or closed. Any of the methods gives its results and helps to find flaws more accurately.

If the damper is one hundred percent closed, a small amount of air enters the cylinders. The maximum pressure in the cylinder will not be huge, about 7-8 atm, because the pressure in the manifold is also not high (1 atm with a 100% open throttle, instead - 0.5-0.6 atm). When the damper is closed, leaks are small, and there are practically no pressure drops. The pressure in the cylinder is very sensitive to leaks - even for a minor reason, the pressure can drop a couple of times.

When the throttle is one hundred percent open, this will not happen. Significantly more air will enter the cylinder, which will lead to increased compression, while leaks will be significantly less than the air supply. As a result, even with severe deficiencies, the compression may not drop to a low level (for example, the low compression of a VAZ 2110 engine will be 9-10 atmospheres).

Based design features various options for measuring compression, we will give some advice on their use.

With the throttle one hundred percent open, compression measurements allow you to find:

• scoring (severe damage) to the cylinder surface;
• burnout or deformation of valves;
• coking (hanging) of the rings in the piston grooves;
• burnouts and piston failures.

With the throttle closed one hundred percent, compression measurements allow you to find:

• valve hanging (in designs with hydraulic tappets - shortcomings in the camshaft cam profile;
• unsatisfactory fit of the seat to the valve.

Thus, for cars without hydraulic compensators, such as the VAZ 2110, it makes sense to determine the compression with the dampers open.

Many VAZ-2110 owners wonder why their cars have different compression? Typically, compression is injected as the piston moves from the bottom to the top. In this case, a certain pressure is created in the cylinder. Good compression can only happen if all gaskets, pistons, rings or valves are in good condition. It is because of these elements that the air in the system is compressed.

Normal compression on a VAZ-2110

Typically, compression is checked using a special device. It is recommended to do this regularly.

This helps determine the degree of wear of the motor and rings, as well as the piston itself. The normal pressure in the cylinder on a VAZ-2110 with 8 valves should be from 10 to 12 atmospheres .

Normal compression in the cylinder.

It is also worth noting that sometimes the pressure in different cylinders may differ . If this 0.5-0.7 atmospheres , then this phenomenon is normal and should not cause concern.

Abnormal compression

This happens when the cylinder has much more or less atmosphere than the others.

Such an engine will not be able to operate normally. He needs to mandatory carry out repairs.

Causes

Burnout of the gasket between the block and the head is a fairly common defect.

There can be many reasons why there may be a difference in compression. Experts highlight the main ones. This:

1. The head and block gaskets are burnt out. It just needs to be changed.
2. The head is not tightened. The gasket may burn out here.
3. The rings don't hold. The reason here is the wear of the rings or their breakage. If the pressure drops in one cylinder, this often indicates a broken ring. This will require piston repair.
4. Coked rings. They will need to be cleaned.
5. Block wear. Happens rarely.
6. Motor overheating.
7. The piston is broken or burnt out. There is no compression at all.
8. Valves not adjusted.

Repair

As can be seen from the above, there are many reasons for different compression in the cylinders. In this case, it is not always possible to carry out repairs yourself, especially if you do not have the skills. In this case, it is recommended to contact specialists at a service station.

Traditional methods of increasing compression

It is noted that the methods described below cannot be a 100% guarantee that compression in the cylinders will increase.

• Buy a quality valve cleaning fluid and pour it into the oil.
• Pour this liquid into the cylinders overnight.

conclusions

Knowing these points, you should not worry about the difference in compression in different cylinders on a VAZ-2110, if it is small. When the norm exceeds the permissible values, repairs will be required.

If, over time, your engine feels like it was more dynamic when it first started, the loss of power may be due to mechanical wear. The most common causes are high wear between the pistons and cylinders, worn piston rings, leaking or burnt valves, and a damaged head gasket or spark plug. At the end of the compression stroke, high compression pressure is created, which then increases like an avalanche during the combustion of the air-fuel mixture. This means high thermal and mechanical stress for pistons and piston rings, cylinder walls, valves, valve seats, valve train gaskets and cylinder head gaskets. As a rule, engines with reduced power already signal their technical condition. Symptoms include erratic behavior during cold starts or uneven engine operation, increased oil and fuel consumption, a plume of white or of blue color, increased coolant temperature, poor exhaust gas performance and reduced engine power. To get a clear picture it is necessary at every second visit service center check compression. This applies equally to diesel engines.

Compression reference values

The compression values ​​for your vehicle vary slightly depending on the compression ratio. Presented in table. 4.2 guideline values ​​are valid for engines in perfect technical condition. When analyzing compression, greater importance is given not to the absolute highest values, but to the same values ​​in all cylinders. Deviations up to a maximum of 2 bar are allowed. If deviations exceed the permissible value, it is necessary to find out the reason for this deviation. As a first step, your specialist will advise you to take a pressure loss measurement.

Older engines create less compression

In older engines, compression decreases significantly, and this is normal due to natural engine wear. Therefore there is no particular cause for concern, it depends less on the absolute highest pressure reading and more on identical values in all cylinders. Only when the measured values ​​reach the maximum permissible values, it is necessary to think about the upcoming repair of the engine or replacing it with another. If the difference in values ​​is more than 3 bar, practice indicates the following reasons:

– wear of pistons or piston rings;

– jamming of worn piston rings in the piston grooves, caused by the deposition of combustion products;

– damage to the working surfaces of the cylinders as a result of slight jamming of the pistons or jamming of the piston rings;

– residues of combustion products and oil in the form of deposits on the valve mechanism or on the working surfaces of the valve seats;

– cracked valves;

– burnout of valves due to insufficient valve clearance or thermal overload.

You can measure compression yourself. First of all, for this you need an assistant who turns the crankshaft with a starter, and a device for measuring pressure. In well-equipped auto repair shops, a compression tester is part of the basic equipment. First, remove all spark plugs (in diesel engine- fuel injectors) from the cylinder head and ensure that the valve clearance is correctly adjusted. During the test, the assistant must fully press the clutch and accelerator pedals; you use the device to check the compression in each cylinder. Since diesel engines draw in the same amount of air at all times, there is no need to press the accelerator pedal. Start measuring with the first cylinder and then sequentially measure in all other cylinders. Count the number of revolutions of the crankshaft before creating maximum pressure, this amount will be the criterion for subsequent cylinders: the faster the compression is created, the “healthier” your engine is. In a “healthy” engine, compression should be created after 6–8 revolutions of the crankshaft.

The basis for a reliable measurement is a functioning starter and a fully charged accumulator battery

Despite the fact that this is an elementary truth, we still remind you once again that the basis for measurement is a starter with good traction force and a fully charged battery. If the crankshaft rotates very slowly, compression in the cylinder also occurs slowly - measuring compression loses its meaning. If you get large deviations in the measurement results, perform a pressure reduction test. Handling the device for measuring compression reduction requires some experience, so we recommend that you leave the test for measuring compression reduction to a specialist.

You can find out the reason for the decrease in pressure as follows.

· If compression is low, inject a little engine oil into each cylinder through the spark plug hole (in a diesel engine, into the injection nozzle hole), then repeat the test. The oil improves the seal between the mating surfaces of the pistons and cylinder walls.

· If the compression has increased slightly, the leak is occurring through the valves or the cylinder head gasket. Leakage through valves can be caused by burnt-out valve seats and/or valve lips, as well as deformed or cracked valve stems.

· If after the introduction of oil the compression increases, then we can clearly conclude that the piston rings are worn out.

Compression measurement

SEQUENCE OF WORK

1. Before measuring, warm up the engine until operating temperature. This creates optimal clearances between all moving parts.

2. Turn off the ignition (terminal “15”), remove the tips from the spark plugs and remove all spark plugs.

3. Tighten parking brake, set the gear shift lever to neutral, press the clutch and accelerator pedals.

4. Firmly insert the rubber cone plug of the compression tester into the spark plug hole (in a diesel engine, into the spark plug hole). fuel injector). If necessary, use a suitable adapter device (