After changing the cylinder head gasket. Problems after cylinder head gasket replacement

It leads to such unpleasant consequences as overheating of the engine, poor operation of the stove, the appearance of exhaust gases from under the hood of the car, the appearance of an emulsion in engine oil, the appearance of white smoke from the exhaust pipe, and some others. If any of the symptoms listed above or one of them occurs, check. There are several ways to do this. Next, we will look at why the cylinder head gasket breaks through, what consequences this leads to, and what to do if this trouble happens to your car's engine.

Signs that the cylinder head gasket has pierced

The task of the cylinder head gasket is to ensure tightness, and to prevent the penetration of gases from the cylinders back up into the engine compartment, as well as the mixing of coolant, engine oil and fuel with each other. In a situation where the cylinder head gasket is broken, the tightness of the block is broken. The following signs will tell the car owner about this:

Signs of a burnt cylinder head gasket

• Exhaust gas outlet from under the cylinder head. This is the simplest and most obvious sign. When the gasket burns out, it begins to let exhaust gases through, which will go into the engine compartment. This will be visible visually, as well as tangible by ear - loud sounds will be heard from under the hood, which are simply impossible not to notice. However, if the burnout is small, then you need to pay attention to other signs.
• Shooting between cylinders. External signs will resemble those that occur when the engine "troit". There is a mixing of the fuel mixture from one cylinder with the exhaust gases in another. As a rule, in this case it is difficult to start the engine, however, after warming up, it continues to work stably. To determine the breakdown, it is necessary to carry out. If this mixing occurs, then the compression value in different cylinders will differ significantly.

  

  Emulsion from under the cap of the expansion tank

• Exhaust gases entering the coolant. If the cylinder head gasket is pierced, then exhaust gases in a small amount from the cylinder block can enter the cooling system. In this case, it is enough to unscrew the cap of the radiator or expansion tank. In the event that gases enter the system in large quantities, the seething will be very active. However, if there are few gases, then improvised means are used for diagnostics - plastic bags, balloons, condom. We will discuss the diagnostic method in detail below.
• Antifreeze gets into one of the cylinders. As a rule, this occurs due to a gasket rupture in the place between the cooling jacket channel and the combustion chamber itself. Often this occurs, even in warm weather. And the level of antifreeze in the tank drops. The more antifreeze gets into the cylinders, the more white vapor will come out of the exhaust pipe.
• Oil leak out from under the cylinder head. These facts can also be signs of cylinder head gasket burnout. That is, there is a rupture of its outer shell. In this case, oil streaks can be seen near the junction of the cylinder head and the BC. However, their reasons may be different.

  

• Significant and rapid increase in engine temperature. This phenomenon occurs due to the fact that hot exhaust gases enter the cooling system, as a result, it does not cope with its tasks. In this case, in addition to replacing the gasket, it is also necessary to flush the cooling system. and with help you can read separately.
• Mixing oil and antifreeze. In this case, the coolant can get into the engine compartment and mix with the oil. This is very detrimental to the engine, because the properties of the oil are lost and the engine is forced to work in unsuitable conditions, which leads to significant wear. This malfunction can be diagnosed by the presence of oily stains in the expansion tank of the cooling system. To do this, open the oil filler cap and look at the inside of the cap. If there is an emulsion on its surface (it is also called “sour cream”, “mayonnaise”, and so on) of a reddish color, it means that the antifreeze has mixed with oil. This is especially true in the case when the car is not in a warm garage, but in the winter on the street. Similarly, you need to look for the presence of the mentioned emulsion on the dipstick to check the oil level.

  

  Wet candles

• Poor oven performance. The fact is that when the cylinder head gasket burns out, exhaust gases appear in the cooling “jacket”. As a result, the heat exchanger of the heater is aired, and, accordingly, the efficiency of its work is reduced. Often, the temperature of the coolant jumps sharply.
• Increase in pressure in the radiator pipes. In the event of gasket depressurization, exhaust gases will enter the cooling system through the nozzles. Accordingly, they will become very hard to the touch, this can be checked simply by hand.
• The appearance of significant soot on candles. In addition, they can literally be wet due to the presence of antifreeze or moisture in the cylinders.

And a clear sign of an engine overheating is the presence of condensate on its surface. This is also an indirect sign of a cylinder head gasket burnout or a crack in the cylinder block. First of all, it is necessary to carry out computer diagnostics of the engine. The presence of errors will indicate the direction and possible additional faults. As a rule, these errors are associated with problems in the ignition system.

Let us dwell again on mixing antifreeze and oil. As mentioned above, as a result of mixing them, an emulsion of a yellowish (most often) color is formed. If it appeared, then one replacement of the cylinder head gasket will not do the repair. Be sure to flush the system from this composition. Including sump and oil channels. And this can cost you additional costs, sometimes comparable to an overhaul of the engine.

We figured out the symptoms that occur when a cylinder head gasket is broken. Next, let's move on to considering the reasons why it can burn out.

Why breaks the cylinder head gasket

In most cases, the reason why there are problems with the cylinder head gasket is a commonplace overheat. Because of it, the cover of the block can “lead”, and the plane along which the gasket is adjacent to two contacting surfaces will be violated. As a result, there is a depressurization of the internal cavity with all the ensuing consequences. Change their geometry, mainly aluminum heads. Cast iron is not subject to such malfunctions, they are more likely to crack than bend, and even then in the most extreme cases.

Scheme of drawing cylinder head bolts on VAZs "classic"

Also, due to overheating, the gasket can heat up to temperatures at which it changes its geometry. Naturally, in this case, depressurization will also occur. This is especially true for iron-asbestos gaskets.

Another reason - bolt torque failure. Both a very large and a small value of the moment have a detrimental effect. In the first case, the gasket may collapse, especially if it is made of low-quality materials. And in the second - to let the exhaust gases out without interfering with them. In this case, gases, together with atmospheric air, will adversely affect the material of the gasket, gradually disabling it. Ideally, the bolts must be tightened using a dynamometer showing the torque value, in addition, the sequence of their tightening must be observed. Reference information on this can be found in the manual.

As a rule, the tightening sequence is that the central bolts are first tightened, and then the rest diagonally. In this case, the twisting occurs in stages. In particular, in VAZ cars of “classic” models the moment step is 3 kgf. That is, all the bolts in the specified sequence are tightened by 3 kgf, after which they are tightened up to 6 kgf, and up to 9 ... 10 kgf.

According to statistics, in about 80% of cases when the gasket failed, the reason for this was incorrect tightening torques or non-observance of its sequence (scheme).

And the most obvious reason low quality material from which the gasket is made. Everything is simple here. Try to buy products in trusted stores. When choosing, you must be guided by the rule of the "golden mean". Gasket, of course, is inexpensive, so you should not overpay, as well as buy frankly cheap garbage. The main thing is that you are confident in the store where you are making a purchase.

It is also possible that the head gasket simply burned out against material wear, because everything has its own service lines.

Examples of cylinder head gasket breakdown points

Also, sometimes the reasons for the operation of the gasket are problems with a violation of the combustion process of the fuel (detonation, glow ignition). Due to overheating, the cylinder head suffers greatly. Cracks may appear in it, which will also lead to depressurization of the described systems. The head is usually made of aluminium. And when heated, it expands faster than steel bolts. Therefore, the head begins to significantly put pressure on the gasket, and it experiences overload. This leads to hardening of the gasket materials, which in turn causes depressurization.

Often when a gasket fails, it burns along the edge or between the cylinders. In this case, erosion of the surface of the cylinder block and the edging itself often occurs near the damage. A change in the color of the gasket material near the edging may also indicate a high temperature in the combustion chamber. To eliminate the malfunction, it is often enough to set the correct ignition angle.

It is important for the driver to understand the difference between the concepts of “breakdown” and “burnout” of the gasket. Breakdown in this case implies significant damage to the surface of the gasket or its individual elements. In this case (and most often it happens), the driver is faced with a burnout. That is, there are minor damage, which are sometimes even hard to find on the gasket. However, they are the cause of the above unpleasant situations.

How to find out if the cylinder head gasket is blown

To understand if the cylinder head gasket is broken, you can use one of several methods. In this case, the diagnosis is simple, and anyone, even a novice and inexperienced driver, can handle it.

To check the integrity of the gasket, do one of the following:

How to check the cylinder head gasket with a condom

One of the effective and popular methods of testing is the method using a balloon or a condom. It is put on the neck of the expansion tank, after unscrewing the cap. The main thing is that the condom sits tightly on the neck and ensures tightness (a bag or a balloon can be used instead of a condom, but the diameter of the condom is usually ideal for the neck of the tank). After you put it on the tank, you need to start the engine and let it run for several minutes at a speed of 3 ... 5 thousand revolutions per minute. Depending on the level of depressurization, the condom will fill with gases quickly or slowly. It depends on the specific situation. In any case, if it began to fill with exhaust gases, this means that the cylinder head gasket is broken.

Condom check

Checking the gasket with a bottle

Another method of how to determine if the cylinder head gasket is broken, often used on trucks. To do this, it is enough to have a small bottle of water (for example, a volume of 0.5 liters). As a rule, expansion tanks have a breather (a tube that maintains the same pressure as atmospheric pressure in a closed container). The method is very simple. With the engine running, place the end of the breather in a container of water. If the gasket is broken, then air bubbles will begin to come out of the tube. If they are not there, then everything is in order with the gasket. If at the same time coolant began to appear from the breather, this also means that everything is in order with the gasket.

Checking the cylinder head gasket on trucks

Checking with a bottle

The two methods described above are suitable for diagnosing a malfunction when exhaust gases break through into the cooling jacket. These methods are very effective and have been used by motorists for decades.

What to do if the cylinder head gasket is pierced

Many drivers are interested in the question, Can you drive with a blown head gasket?? The answer is simple - it is possible, but undesirable, and only for short distances, in particular, to a garage or car service for repair work. Otherwise, the consequences of what pierced the cylinder head gasket can be the most deplorable.

If, as a result of the diagnostics, it turned out that the gasket was broken, then there is nothing to be done about it, except to replace it. It is also worth examining the adjacent surfaces, and most importantly, try to find out the true cause of the burnout ... The price of the gasket may be different and depends on the brand of the car and the manufacturer of the spare part itself. However, compared to other nodes, it is low. Repair work can cost you a little more than just buying a gasket. The point is to take into account the following points:

• If, during the dismantling of the cylinder head, it is found that the mounting bolts “led” and they do not meet the technical parameters, they will need to be replaced. And sometimes there are situations when, due to a change in the geometry of the cylinder head, the bolt cannot be unscrewed, and it simply has to be torn off. To carry out this unpleasant procedure, there is appropriate equipment. Often, bolts are installed on modern engines that operate at their yield strength. And this means that after removing the cylinder head (to replace the gasket or for other reasons), it is necessary to buy and install similar new ones.
• If the plane of the cylinder head is broken, then it will be necessary to grind it. For this, special machines are used, the work on which will also cost money. However, the working plane of the cylinder head “leads” not so often, but it’s still worth checking this parameter. If the surface has been polished, then a new gasket must be purchased, taking into account the thickness of the removed metal layer.

Before replacing the gasket yourself, it is necessary to clean the head from soot, scale and pieces of the old gasket. Next, you need to revise its surface. To do this, use a special measuring tool, usually a ruler. It is carried out over the surface, revealing the presence of gaps. The size of the gaps should not be more than 0.5 ... 1 mm. Otherwise, the surface of the head must be ground or completely replaced with a new one. Instead of a ruler, you can use a thick sheet of glass (for example, 5 mm thick). It is placed on top of the surface of the head and looked for the presence of possible air spots. To do this, you can grease the surface of the head with a little oil.

Cylinder head surface check

When replacing the gasket, it is recommended to lubricate its surface with graphite grease. So it will become softer and easier to find “its” place on the surface of the cylinder head. In addition, when dismantled, it will be easier to remove. The advantage of graphite grease in this case is that graphite is not squeezed out during operation, turning into ash.

After repair work, the car owner must monitor the behavior of the motor. Do the malfunctions described above reappear (white smoke from the exhaust pipe, emulsion or greasy spots in the coolant, oil at the junction of the cylinder head and BC, there is no engine overheating, and so on). And immediately after the replacement, you should not operate the engine at maximum power. It is better that the gasket “settled” and took its place.

What is the best gasket material

Gaskets from different materials

When replacing a gasket, many car owners have a reasonable question, which gasket is better - made of metal or paronite? Each of these materials has its own advantages and disadvantages. It should be understood that if the manufacturer recommends the use of gaskets from a certain material, then these requirements must be followed.

As a rule, a metal gasket is stronger than its paronite counterpart. Therefore, it is advisable to put it on powerful turbocharged or forced engines. If you do not plan to tune the engine of your car, but simply operate it in a gentle mode, then the choice of material does not matter much to you. Accordingly, a paronite gasket is also quite suitable. Moreover, this material is more flexible, and is able to adhere more closely to work surfaces.

Also, when choosing, it must be taken into account that the material from which the gasket is made does not have a primary impact on its service life. A much more important indicator is how the gasket was installed. The fact is that there are very thin walls between individual groups of holes. Therefore, if the gasket is not installed exactly on the seat, then there is a high probability of burnout even for the strongest material.

The most obvious sign that the gasket was installed incorrectly is its rapid failure. Also, if you installed it incorrectly, the car may simply not start. In diesel engines, the sound of pistons can still be heard. This is due to the fact that the piston touches the edge of the gasket.

Conclusion

If you have a broken cylinder head gasket, then it is undesirable to drive a broken car. Therefore, we recommend that you replace the gasket immediately if it is found to be broken. In addition, it is important not only to discover the very fact that it is broken, but also the reason for this. In particular, why the engine overheats or other malfunctions occur.

During the replacement process, check the value of the moment on the mounting bolts. Timely replacement of the cylinder head gasket will save you from large financial expenses for the repair of more expensive components. The longer you drive a car with a blown cylinder head gasket, the more likely it is that other, more expensive and important engine components will fail.

Not always, after replacing the cylinder head gasket, the engine starts to work flawlessly - sometimes new problems appear. What unpleasant phenomena can arise, what are the reasons for their occurrence, and how to fix the problem that has arisen - we will tell in this article.

Possible malfunctions after replacing the gasket are as follows:

• engine breakdown,
• car won't start
• white smoke from the exhaust pipe
• the sound of hydraulic lifters.

Let's consider separately each of the faults.

Engine Trouble

If, after replacing the cylinder head gasket, the engine troit, then this may occur as a result of the following reasons:

1. If the gasket is not installed correctly, or the gasket itself is of poor quality. It is necessary to remove the installed gasket, inspect and make sure that there are no microcracks or other damage on it (). If the condition of the gasket is normal, then it should be reinstalled, otherwise, install another part.
2. Clogged or faulty nozzles, which, by the way, need to be changed during repairs related to the cylinder head. Among the new nozzles, defective specimens may come across - to exclude such a possibility, you can try to put, for the test, the old nozzles removed and then listen - the engine is troiting or has stopped.
3. An insufficient level of compression in the cylinders can cause the engine to triple after replacing the cylinder head gasket. Here you will learn -,.
4. Faulty hydraulic tensioners. Here, the recommendations are the same as in the case of injectors - with each repair related to the cylinder head, the hydraulic tensioners should be replaced with new ones.
5. The idle or ignition is not adjusted - this problem most often happens with old, domestic cars. Here you will learn -,.

Car won't start

Another problem that occurs after replacing the cylinder head gasket is the inability to start the car. Possible reasons are as follows:

• Gasket defective or not installed correctly. To check this, dismantling and inspection of the gasket is required.
• Insufficient compression level in the cylinders.
• Wear of oil scraper rings.
• Wear of the runner in the ignition distributor, as a result of which there is no ignition spark. Remove the distributor and inspect it for the integrity of all its components.
• Ignition not adjusted.

White exhaust smoke

If, after replacing the cylinder head gasket, white smoke comes out of the exhaust pipe, then this may be due to:

1. Cracks in the cylinder head. You can remove the crack only by welding in the service, if it is not large, otherwise the entire head may need to be replaced.
2. Thick white smoke coming out after the engine warms up can appear as a result of antifreeze entering the cylinder block - when coolant seeps through worn oil seals or a cylinder head gasket.
3. In the design of some older cars there is a valve with a vacuum hose for the engine. When white smoke comes out, this may be due to the fact that, through the said valve, oil flows from the gearbox. And then there is pollution of the spark plugs and the failure of one of the cylinders. To exclude such a development of events, you need to check this valve and, if necessary, replace it with a new one.

Knock of hydraulic lifters

It happens that after replacing the cylinder head gasket, hydraulic lifters begin to knock. Some reasons for knocking:

• If the knock of the hydraulic lifters occurs only during engine start, then this is possible as a result of the fact that engine oil is leaking somewhere. This is normal if, after replacing the cylinder head gasket, the car has not been used for a long time and has stood. The leak usually stops on its own.
• If the knock of the hydraulic lifters occurs only during the warming up of the car, and when the speed increases, it disappears, then the cause may be either contamination or wear of the check valve. You can fix the problem, respectively, either by cleaning or replacing the hydraulic compensator. When cleaning, you need to change the engine oil at the same time.
• If the knock of the hydraulic lifters occurs only on a hot engine, and everything is normal on a cold one, then the plunger pair has probably failed, and it needs to be replaced.

Why do hydraulic lifters knock: causes and troubleshooting - this is dedicated to

Here you see a bunch of iron in front of you, which is assembled into a very necessary and convenient mechanism for you - your car. Look and think about the fact that people have created such a unit, but suddenly it may happen that because of some small detail the car will stop driving. Information about when the cylinder head gasket will need to be replaced will not be superfluous for any car owner. Even though you will not repair your car, you need to know what it can lead to if you do not replace the cylinder head gasket at the right time.

What is the cylinder head gasket for?

This part is used to seal the place where the cylinder block and cylinder head are connected. Don't compare head gasket and cylinder head cover gasket, which is made of rubber. Although these concepts are almost the same, there are differences.

The cylinder head gasket does three things at the same time - this is the seal of the engine cooling system (channels), the seal of the engine oil system (channels), and the seal of the gas distribution system of the engine (cylinder cavities). It is because of this that the requirements for this part are high. Do not forget and try to somehow save money on repairing the cylinder head or cylinder block. A gasket is a part that is used only once, and with any engine repair, it must be replaced with a new one.

What types of cylinder head gaskets exist:

1. Non-asbestos- such gaskets are characterized by low shrinkage and high material recovery.

2. Asbestos- this type of gaskets is similar in characteristics to non-asbestos gaskets, they have such properties as: elasticity, heat resistance and elasticity. This type of gaskets is most often used as repair kits.

3. Metal- this type of gaskets is considered the highest quality and most effective. When using this type of gaskets, a more uniform distribution of the specific surface pressure occurs at the junction along the entire plane of the cylinder head and block.

When is a head gasket replacement needed?

Replacement of this part may be needed at any time, and how long it will last is not known. There are some signs of cylinder head gasket failure and failure, which we will list below:

1. At the junction of the cylinder head and the block, external leakage of engine oil or coolant is possible.

2. When checking the oil on the dipstick, a whitish liquid is noticeable - this may possibly appear due to the ingress of coolant through a failed gasket.

3. If white smoke is emitted from the exhaust pipe all the time, except for warming up the car, then most likely the coolant has entered the cylinder.

4. If there are oil stains while checking the expansion tank or on the surface of the liquid in the radiator, then most likely the engine oil is entering the cooling system due to a bad gasket.

5. And the last sign of a faulty gasket is the ingress of exhaust gases into the cooling system, this is evidenced by the appearance of bubbles in the radiator or in the expansion tank. All these signs of a faulty gasket are not an accurate confirmation. But still, you can’t ignore them, since soon this part will still need to be replaced. No matter how we avoid this moment.

The sequence of work when replacing the cylinder head gasket

On almost all brands of cars, the work of replacing the cylinder head gasket is the same. But there are some features, such as the order in which the cylinder head bolts are tightened and the setting of the tightening torque of these bolts. These figures are indicated in the owner's manual for your vehicle. If you do not have a manual, you can use the Internet to find this data. It is extremely important before starting to unscrew the cylinder head mounting bolts, to clean them so that the keys do not break off, in order to prevent the formation of a defect in the bolt slot and the inability to unscrew it. Unscrew the fastening bolts starting from the middle or first turn all the bolts evenly by 0.5-1 turn.

Before starting work, you must disconnect all attachments. And the dismantling procedure itself is best marked or indicated schematically. After unscrewing the bolts, it is necessary to remove the block head and replace the cylinder head gasket. To center the gasket itself and the block head, there are usually bushings on the block itself. After that, install the cylinder head and all attachments in the reverse order. Especially for this moment, you sketched a diagram. It is necessary to tighten the cylinder head bolts in strict order with the drawing for this block and at the same time it is necessary to observe all the torque parameters specified by the manufacturer. To do this, you need to use a torque wrench.

The main points when replacing the cylinder head gasket

Regardless of any features associated with a particular engine, the type of gaskets and mounting bolts, there are rules and regulations that should be followed. The rules that you need to know when replacing the cylinder head gasket, regardless of the brand of car. We will not bore you with the details of which bolt and how to tighten. All the subtleties of replacing the cylinder head gasket are listed in the manual specifically for your type of motor. Read them before starting repairs. It is very important to try to fulfill all the described requirements of the manufacturer, which relate to the collection and disassembly of the cylinder head.

1. When disassembling, you must hold a marker in your hands. When disconnecting all attachments, in particular pipelines, you do not need to be lazy and rely on memory, you need to mark everything. It will be much easier to collect later.

2. When buying this replacement part, be sure to make sure that it is suitable for exactly the torque that the engine manufacturer writes to tighten the cylinder head bolts.

3. Before unscrewing the mounting bolts, they must be very well cleaned of plaque. If a key break occurs, then you may get injured, or you will get a break in the slot of the bolt, which will then have to be drilled.

4. The untwisting of the fastening bolts starts from the middle by 0.5-1 turn. Need it to relieve stress.

5. After you have done all the necessary work related to replacing the cylinder head gasket, you can begin to assemble everything back. Everything must be done carefully and carefully.

6. Tightening the cylinder head bolts must be done only using a torque wrench, while observing all the rules and parameters.

After you have assembled the cylinder head, then all attachments must be put in their places, according to your scheme. After the repair, for some time you need to focus on the above signs. If all is well, then you replaced the cylinder head gasket correctly.

Features to be aware of when replacing gaskets

As with any other work on your car, you will need a lot of attention and care. In some brands of cars, there may be different fastening and docking technologies, but in general, all actions must be almost the same and similar (universal for all cars):

1. Of course, first you need to disassemble everything, while marking every detail, no matter what, this is necessary in order not to forget anything and there are no extra details.

2. When buying a new gasket, you need to make sure that it meets all the specifications, and in particular the torque that is suitable for your motor.

3. After the old gasket has been replaced with a new one, the cylinder head must be installed with precision along the guides.

4. How to unscrew and tighten the bolts must be very careful not to strip the threads and gradually distribute the stress on all the bolts.

5. And finally, the main thing is not to forget, to fix all the details correctly.

We replace the cylinder head gasket ourselves

We already mentioned the moments of replacing the cylinder head gasket earlier in this article, but now we will clarify something again. In fact, replacing the cylinder head gasket is not difficult. You just need to do everything very carefully so as not to damage anything. Bolts cannot be torn off, because they will not hold the cylinder head later. No one wants this kind of trouble. Before starting work, you must read the operating instructions for the machine, find out everything that can be useful. If there is no instruction, then you can read the information on various automotive forums.

Let's talk a little about bolts. Before spinning the bolts, they must be cleaned of dirt, burning and other deposits. After that, start unscrewing, as described earlier. The dismantling of the cylinder head must not be started when the attachments are turned on. It is necessary to disconnect all belts, filters and devices. But do not forget to sketch everything, write it down or take pictures on your phone. As soon as the head is lifted, the gasket can be replaced. According to the bushings, you will put the gasket evenly.

All that needs to be done is to put the cylinder head in place and all other equipment, and then tighten the bolts. It is advisable to do this using a torque wrench. If you are not confident in yourself, then the best option for you would be to contact the workshop, where everything will be done quickly and efficiently. The cost of such work is rarely very high. We wish you success!

Many people call the engine the heart of the car. In fact, this is how it is. It is the motor that drives the car. ICE is the most expensive unit in any car. This node consists of several components. In addition to attachments, there is a block and a cylinder head. Each detail has its own device and purpose. And today we will look at what a cylinder head is in a car, and why the car may not start after replacing its gasket.

Characteristic

Cylinder head stands for cylinders. This is one of the most critical components in a car engine.

It is the cylinder head that is responsible for controlling the combustion of fuel, as well as for the removal of exhaust gases.

Material

For many years, the head was made from the same material as the block. It was cast iron. But since the 1980s, cast iron has been replaced by aluminum. It is from this material that 90% of all heads are made.

But not all engines have the ability to use aluminum cylinder heads. The reason is the high temperature regime, in which deformation and thermal shrinkage of the metal is possible. Therefore, cast-iron cylinder heads are still used on such engines.

Device

Structurally, this node combines:

• Carter. This is the block head housing.
• Spark plug. For them, special threaded holes are provided in the head. Candles are involved in the ignition of the fuel mixture. There are none on diesel engines.
• Nozzles. Designed to supply fuel under pressure.
• gas distribution mechanism. It consists of pulleys, (maybe several) and valves. The latter are further divided into two types. So, there are intake and exhaust cylinder head valves. What is a valve in a car? These elements are responsible for the timely injection of fuel and the removal of gases from the chamber, which are formed after the ignition of the mixture.
• combustion chamber. Each cylinder has its own. Its volume may be different, depending on the configuration of the cylinder head.

Between the head housing (we have already found out what a cylinder head is in a car) and the block, an asbestos gasket is necessarily placed. Also in the design of the head there are non-removable parts. They are installed by hot pressing into the cylinder head crankcase. What is it in the car? Non-removable parts are valve seats. They are installed in the place where the block head contacts the closed inlet or outlet valve. Saddles are a massive steel ring with a conical profile. If they are defective, you must use a special tool for replacement. At home, such an operation is not performed.

How to install

The cylinder head is superimposed on the engine block from above. It is fastened with long bolts or threaded studs. Since the landing area is large, during installation, the sequence of tightening the bolts is observed. This will eliminate structural deformations and possible breakdowns, as well as gas breakthrough.

Note that on in-line power units, the cylinder head covers the entire block. And on V-shaped motors, each row has its own head. But regardless of the type of layout of the cylinder block, a reinforced gasket is installed between the head and it. What is a cylinder head gasket in a car? This is a sealing element. The gasket is made of a hard refractory material that prevents the coolant from mixing with exhaust gases and oil. Such a part is installed on all internal combustion engines. The only exceptions are some sports internal combustion engines. Here the head is ground so evenly and smoothly that its contours completely coincide with the cylinder block.

Car won't start after head gasket replacement

Sometimes it happens that this element loses its tightness. In simple words, the gasket burns out. In this case, when the engine is started, the car smokes. After replacing the cylinder head gasket, everything should return to normal. But if the labels are set incorrectly, then the car may not start at all. But when replacing or repairing the head of the block, you will definitely come across such a mechanism as the timing. It is driven by a belt or chain. The torque comes from the crankshaft of the engine. When dismantling a belt or chain, be sure to mark the location of the pulleys. When installing the drive, it is important to observe the accuracy of the marks. The slightest deviation can cause the car to not start after replacing the cylinder head.

A more serious outcome is a failure of the gas distribution phases. This is fraught with bent valves and damaged pistons. By turning the starter only once, you can fly into a large amount of repairs.

How to solve a problem

Consider the process of labeling on the example of a VAZ-2109 car. For work, we need a good flashlight, a slotted screwdriver, as well as keys for 17 and 19. After installing the timing belt tensioner pulley, you need to turn the camshaft pulley. You need to twist it until the mark matches the bar that is on the engine block. After that, leave the camshaft alone.

Let's move on to the crankshaft. Here, too, there are labels. A bolt must be screwed onto this shaft. This makes labeling faster. Turn the shaft until they are in a vertical position. Next, remove the rubber plug in the clutch housing. After that, we will have access to the flywheel. Why do we need it? There is also a mark here, which ideally should coincide with the slot of the bar that is attached to the cylinder block. If these designations match, then we have correctly set the position of the timing elements. After that, you can safely install the belt. First, it is put on the crankshaft pulley, and then the camshaft.

Finally

So, we found out what a cylinder head is in a car. The head of the block is a very important unit in any engine. At the slightest malfunction, problems arise with the operation of the entire power unit. If the gasket is broken in the engine, do not hesitate to replace it. Otherwise, gases will penetrate the cooling system and mix with antifreeze. And the latter will enter the combustion chamber, due to which thick white smoke will come out of the exhaust when the engine is running.