The importance of all fastening elements in the engine is very high. This is an axiom. Tightening the cylinder head bolts is no exception.

Features of tightening the cylinder head bolts

Cause? And it is simple. Just think about the stresses that all fastening elements are subjected to: constant vibration, extreme temperature fluctuations. As a result of the research carried out, the figure was 5000 kg. and higher. This is approximately the same full throttle breaking load for each bolt in the engine.

One of the main conditions that guarantee the correct action when or when is the compliance with the manufacturer's requirements. Different engine models have different cylinder head tightening torques. The order of tightening the cylinder head may also differ. There are recommendations in the manuals for each model, and they must be followed.

Having its own characteristics, in relation to different models, tightening the cylinder head bolts, has nuances that are applicable to the procedure for tightening cylinder head bolts in general, and are the same for everyone.

And it is advisable for you to know them, since no one guarantees that the service will do you competently and as for yourself.

The tightening torque of the cylinder head is influenced by:

• Lubrication of the threads of the holes and the bolts themselves. It is recommended to lubricate with non-viscous types of engine oil.
• The condition of the threads, both the hole and the bolt itself. Deformation and clogging of the thread before tightening are contraindicated, this can lead to a decrease in the compression force of the gasket with all the consequences ...
• New bolt or has already been used. The new bolt has higher resistance and the tightening torque may be distorted. It is desirable that when using new bolts, the cylinder head bolts are tightened after 2-3 bolt tightening and unscrewing cycles. It is recommended to tighten the bolts to 50% of the final tightening torque and loosen them.

Particular attention should be paid to the accuracy of the tool, namely the torque wrench, when tightening the bolts. Dial indicator keys are both convenient and accurate. But, they react sharply to falls and blows, like any precision instrument.

• Refer to the manufacturer's instructions, which clearly indicate the torque and order of tightening the cylinder head.

• The bolts must be in perfect condition. Do not economize, and in no case cut the thread. After all, you do it for yourself.

• Bolt threads and holes must be clean. The wire brush is in your hands.

• In the case of a "blind" bolt hole, try not to overflow with oil, otherwise the bolt will not fully fit. And it will be useful to lubricate the threads with a plastic sealant if the hole goes into the engine cooling system.

• Bolts of the TTY type (usually used in engines with aluminum cylinder heads) are strictly prohibited from retightening, as they may break. Their repeated use will also not be able to provide the necessary compression of the gasket, which means leakage.

• When installing the gasket, be sure to check with the gasket manufacturer's specification for the tightening torque. If you have past experience with replacing gaskets, forget about it. Each engine has its own specifics.

• Returning to the bolts of the TTY type, you need to emphasize that there is a clear degree for them, and not the tightening torque of the cylinder head bolts. That is, you need a tool with an angle indicator.

• Stretching or, if necessary, is made for engines: with cast-iron cylinder heads on a hot one, and with aluminum cylinder heads on cooled down to room temperature.

Good luck with your own hand tightening of the cylinder head.

Expert opinion

Ruslan Konstantinov

Automotive expert. Graduated from ISTU named after M.T. Kalashnikov with a degree in Operation of Transport and Technological Machines and Complexes. More than 10 years of professional car repair experience.

When tightening the cylinder head bolts, many, due to inexperience and ignorance, can make a lot of mistakes that can cause serious repair work in the future. Often, incorrect tightening leads to damage and deformation of both the cylinder head and the block. The most common mistakes are oil getting into the bolt wells, working with an unsuitable or worn sockets for a torque wrench or tightening without it at all, tightening the bolts, my violation of the tightening order, as well as using the wrong size bolts (long or short on the contrary).

Often, the wells where the bolts are screwed become covered with rust or clogged with dirt, it is not always possible to clean them. It is strictly forbidden to pour oil into them, just like screwing the bolts into the dirty holes, otherwise it is impossible to achieve the required effort. Oil can only be applied to the threads directly on the bolts. Often there were cases when, when these tips were ignored, the well collapsed, and this threatens to replace the cylinder block, since it is not always possible to repair it.

It is impossible to tighten without a torque wrench, under no circumstances, tightening the bolts "by eye" is almost always done with an excess of the permissible effort, this leads to breakage of the bolts and repair of the cylinder block. It is also recommended to always use new bolts, even if the old ones look perfect, the fact is that they tend to pull out after tightening.

Every car owner who is faced with the repair of the cylinder head, after completing the task, will have to put this element in place. This procedure implies. Failure to do this may compromise the tightness of the unit. Below we will analyze which torque of the VAZ 2106 block head is most important and what to consider when installing the device.

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When should you tighten?

To begin with, let's consider in what cases it is required to pull the bolts of the cylinder head of the engine of a VAZ 2106 car:

1. If engine oil comes out from under the cylinder head. The problem indicates damage or natural wear of the head gasket. It is necessary to remove and replace the seal. The leak can also be attributed to loosening of the cylinder head bolts. The presence of a problem is indicated by oil stains that have appeared at the junction of the head with the motor block.
2. After repairing the power unit. If you removed the fasteners in a Niva car or any other and went over the engine, then for a successful assembly, you should take into account the order of the constriction and the scheme, as well as the tightening force of the screws.
3. For prevention purposes. Experts recommend tightening the bolts on the cylinder head every 2-3 thousand kilometers. When the engine is operating under vibrations, the screws may loosen and must be checked periodically and tightened with proper torque.

Channel Ilyich's Garage published a video that will allow you to understand the process of tightening the bolts of the block head on the "six".

How to tighten correctly?

You can stretch the bolts with the help of specialists or yourself. If you have never encountered the need to complete this task before, then below we will analyze how tight the screws should be tightened and in what sequence to do it.

Observe the tightening torque precisely, as overtightening the head bolts will crack and damage the cylinder head. If this happens, the car owner will have to overhaul the unit. The working surface of the hole, as well as the screw thread connection, must be as clean as possible. An iron wire brush can be used to clean the cylinders. If during the course of the task you find "blind" holes for the head screws, then use lubricant carefully. If the volume of the substance is more than required, it will be difficult to install the pin until it stops.

Before tightening, it is necessary to perform a visual diagnosis of the condition of the bolts. If the fastening elements are damaged or worn out, their quality is generally low, then it is better not to tighten these screws, it is recommended to replace them with new ones.

Tools and materials

To tighten the cylinder head, prepare only one tool - a torque wrench, which will determine the tightening force of the screws. It is best to buy a key in a specialized store or rent it from a service station, since this tool can only be used for tightening and tightening. Using a regular wrench will not determine how many kilograms of tightening force is.

Channel "Engine Repair! And interesting! " released a video that describes all the nuances of the stretching process.

Algorithm of actions

Sequence and force needed when pulling the cylinder head bolts:

1. Use a torque wrench to tighten all bolts according to the diagram below. The tightening torque on the first circle of fastening tightening will be about 3.5 - 4.1 kgf / m. First, the bolts are tightened, which are located in the center of the block head - above and below. Then the two upper and lower fasteners are screwed down, mounted on the side of the screws located in the center. Then the two extreme bolts are tightened. Note that tighten the left pins first, then the right pins. The screw number 11, located at the bottom left, does not need to be touched.
2. This is the first stretch circle. In the second step, the bolts are tightened in a similar manner. Only the force with which the fastening elements are pulled by the tool will be 10.5 - 11.5 kgf / m.
3. At the third stage, the bolt is tensioned, which is marked with number 11 in the diagram. The tightening force of this screw should be 3.5 - 4.0 kgf / m.

Greetings to you friends on the do-it-yourself auto repair site. The cylinder head (cylinder head) is an important element of the power unit, which only at first glance seems simple.

The mechanism includes spark plugs, gas distribution valves, combustion chamber blocks, and so on.

In this case, the cylinder block itself and its head are separated by a special gasket made of a special material (usually steel asbestos).

The head and block are fixed using special bolts, which are always tightened with a certain effort.

Do you need a cylinder head broach?

On new cars, broaching the cylinder head is not necessary for prevention purposes.

Previously, manufacturers obliged to do this work already at the first MOT, but in new machines this need has disappeared.

If you are the owner of an old VAZ, Moskvich or UAZ, then you will have to do this work much more often.

The need for broaching can arise in several cases:

If an oil leak appears in the place where the cylinder block and the head are connected. Such a malfunction may indicate a loosening of one or more bolts or a malfunction of the gasket itself;

after renovation. There are situations when mistakes in broaching are made by "specialists" at the service station. In this case, you have to redo everything;

periodic check. After 1-2 thousand kilometers after repairing the cylinder head, it is advisable to unscrew the cover and check the tightening torque. There are times when the bolts are loosened during operation.

How to do the job?

Please note that in order to do the job well, you should carefully study the repair manual for your car.

The rules for tightening the cylinder head are clearly described there, namely:

• Bolt pulling diagram;
• required tightening torque;
• the types of bolts to be used for this job.

You may need this information if one or more bolts need to be replaced.

And in general, the issue of bolts for the cylinder head needs detailed consideration. It is no secret that today manufacturers use better quality products with better characteristics.

So, on new motors, so-called spring bolts are increasingly used, which it is enough to tighten once and not touch any more. Moreover, if this rule is violated, then the fastening, on the contrary, will be loosened and the bolt may be damaged.

Many experienced car enthusiasts install high-quality gaskets that do not shrink over time. In this case, the likelihood of loosening the broach can be minimized.

If you decide to check the tightening torque of the bolts, then take into account the order of pulling the cylinder head and use a working torque wrench.

How to control the quality of work?

Be sure to check the tightening torque to ensure the quality of the work performed (use a torque wrench for this).

When doing the job, you must wait until the bolt reaches its "yield point". It's easy to diagnose. Once you set the required torque, it will not change.

There are two important points to keep in mind. If you increase the torque to a level of 20 kgcm, and the bolt does not turn, then it must be changed.

The reason is too much strength. If it is impossible to tighten the bolt and the moment decreases all the time, then it should also be replaced.

Finally, let's highlight the main tips that are important to consider when doing this kind of work:

There is no point in listing them, since they may differ for each model.

2. When pulling the bolts, use only a working torque wrench. Do not rely on your "eye" and "good old" wrench.

3. If there is any suspicion of poor quality of the bolt, replace it. Here the “yes, it will” principle can lead to many problems in the future.

Before tightening the bolts, be sure to check the cleanliness of the thread and its condition.

Please note that reuse of spring bolts is prohibited - you will still not achieve proper pulling.

As a result, after a few hundred kilometers, the oil will begin to squeeze out from under the gasket.

4. Pay special attention to the choice of the gasket - it must indicate the permissible torque (it is not advisable to exceed it).

In doing so, make sure that the numbers on the product at least approximately correspond to the manufacturer's recommendations.

5. If there is a "blind" mounting bolt, carefully fill in oil. Otherwise, it can be "overdone" and the bolt simply will not tighten to the desired moment.

If there is a through hole, it is advisable to treat the thread with a special sealant.

Remember that it is not difficult to stretch the cylinder head. The main thing is to strictly follow the manufacturer's requirements and take into account the recommendations in the article. Good luck on the road and, of course, no breakdowns.

Periodically, the cylinder head gasket may fail due to wear of its material or its burnout. The main signs that it is time to replace the gasket with a new one are the appearance of local leaks of oil and coolant at the point of contact between the cylinder head and the motor.

It should be remembered that when replacing the gasket, not only the tightening torque of the cylinder head of the VAZ 2114 is important, but also the entire sequence of operations - after all, the replacement itself is a very important and serious procedure, mistakes during which can lead to engine malfunction.

Required tools and process

In order to do it correctly, you will need:

• set of socket heads;
• extension;
• ratchet / crank;
• torque wrench.

The replacement process itself should be carried out according to the following scheme:

1. Disconnect the wires suitable for the emergency oil level and coolant temperature sensors.
2. Drain off coolant.
3. Dismantle the thermostat.
4. Remove the air filter housing.
5. Disconnect the inlet exhaust pipe from the manifold.
6. Remove the casing, as well as the camshaft belt itself.
7. Disconnect both damper rods from the carburetor.
8. Disconnect the wires suitable for the cylinder head.
9. Disconnect hoses suitable for cylinder head by loosening their clamps.
10. Remove the cylinder head.
11. Remove worn gasket.
12. Clean the contact surface of the cylinder head from the remnants of the gasket material.

The installation of the gasket and the installation of the cylinder head in its place is carried out in exactly the same sequence, but in the reverse order. At the same time, it is worth paying close attention to such a factor as the tightening torque of the cylinder head of the VAZ 2114 8 valves - we will talk about it below.

How to tighten the cylinder head bolts correctly?

Before proceeding with the installation of the block head, you should first pay attention to the condition of its bolts. They must have good threads and be in accordance with the required standards in length.

The normal overall length of the cylinder head bolt is 135.5 mm. If the bolts removed during the replacement of the gasket meet this parameter, then they can be reused. If the bolts have lengthened during engine operation, then they can no longer be used and new ones should be purchased.

Having dealt with the bolts in this way, and having installed them in place, you should proceed to tightening. It is performed without fail only with a torque wrench. Tightening the bolts "by eye" can lead to very serious consequences, up to and including damage to the engine itself.

And so, how to stretch the head on the VAZ 2114 correctly? First, remember to start tightening the bolts from the center outward.

This diagram looks like this:

• 7 3 1 4 9
• 8 6 2 5 10

Secondly, tightening should be performed in four stages (each of which is performed in exactly the same sequence as indicated in the diagram above).

At the first stage, we tighten each of the bolts with a torque wrench with a force equal to 2 kgf / cm2.

At the second stage, we tighten all the bolts with a force of 8 kgf / cm2.

At the third stage, we tighten the bolts, turning each of them at an angle of 90 degrees.

At the fourth stage, we again turn each of the bolts (still adhering to the diagram at the beginning) through an angle of 90 degrees.

After all four stages are completed, the tightening of the cylinder head bolts can be considered complete.

Tightening the cylinder head bolts should be taken as seriously as possible. It is necessary to perform all its stages strictly in the same order and with equal effort on each of them. Failure to observe this rule can lead to rapid wear of the gasket and the appearance of oil and coolant leaks.

Correct operation with a torque wrench

A tool such as a torque wrench, which allows bolts to be tightened with equal torque, requires great care and skill.

The approximate sequence for tightening the bolts with such a wrench is as follows:

• set the holder to the "zero" position;
• start a smooth rotation of the instrument, while monitoring its readings;
• if the rotation of the tool (especially at the initial stage of tightening) occurs without changing the torque on the indicator, then this may indicate a slight internal tension of the fasteners. This is completely normal and the rotation of the instrument should be continued;
• when reaching the tightening torque corresponding to the required, the movement of the tool should be stopped.

Instead of a torque wrench, you should not use any other tool (including a mechanized one with the ability to normalize the tightening force). After all, only a key can achieve absolutely precise and smooth tightening of the bolts, due to which the gasket will be evenly pressed over the entire surface of the block. This will help to maximize its service life, to avoid burnouts, oil leaks and coolant leakage.

Useful video

You can find additional useful information from the video below:


Well, at the end, it should be reminded once again that before starting the tightening, you need to check the length of all the bolts (it should be equal to 135.5 mm). If the length differs from the indicated one, especially in a larger direction, then there will be no sense even from the most careful tightening of such bolts.

Repair of the cylinder head (cylinder head) is an important process that determines the operation of the engine and the car. And tightening the cylinder head is one of the key points in the overall repair of the unit. Reliable, correct and economical operation of the engine depends on the high-quality and correct tightening of the cylinder head.

What does the tightening of the cylinder head affect?

A similar work (tightening) is done when the reverse process is carried out to assemble a car engine. And how correctly, reliably and tightly the cylinder head bolts are tightened can greatly affect the operation of the combustion chamber, gas distribution mechanism and the engine as a whole.

In the event that the cylinder head is tightened incorrectly, or in the wrong sequence, or weakly, this can lead to a breakdown of the gasket, which is installed between the cylinder head and the cylinder block. After damaging the gasket, the consequences are difficult to predict correctly. Most often, after this, water from the cooling system enters the engine oil. The result is an emulsion that lubricates engine parts much worse than engine oil, and therefore the engine can quickly "jam".

In addition to water entering the engine oil, the engine power may sharply decrease, the sound of the engine may sharply increase, etc. In any case, there will be nothing good after an incorrect tightening of the cylinder head.

To tighten the cylinder head bolts with sufficient force, be sure to use a special tool, in this case a torque wrench. It has a special scale that will allow you to determine the force with which you need to tighten the cylinder head bolts. Each motor has its own tightening parameters, you will learn them from the repair manual for the motor of this machine.

Next, we will try to explain in detail and demonstrate in the photo the key points of how to properly and securely tighten the cylinder head bolts in order to ensure reliable and correct operation of the car engine for a long time.

Tightening instructions for cylinder head bolts

As mentioned above, we only use a torque wrench to tighten the cylinder head. It is impossible to tighten the cylinder head with the required force with open-end wrenches or box wrenches, even if you use additional tools, a crowbar or a pipe.

The dynamometer located near the handle shows how much force was applied when tightening, and this requirement must be met accurately. A slight deviation from the requirements is allowed, of the order of 0.5 kg / m.

After taking the torque wrench, remember the second requirement - the order of tightening the bolts (nuts) of the cylinder head. The order is a certain scheme that must be strictly followed.

The central nuts (bolts) are tightened first, and then gradually move to the edge of the cylinder head.

There are several schemes for tightening the head, and they are all correct. The main thing is to observe the "iron" rule: tighten the bolts (nuts) in pairs from the center to the edges. And do not try to tighten completely at once, this can distort the head. Tighten in three stages: first tighten the bolts (nuts) slightly, then tighten strongly, and then finally tighten strongly. For the first tightening, set the wrench dynamometer to the 3 kg / m position, then more. Intermediate puffs should be "sounded" by the characteristic crackling sound. This sound means the nut (bolt) has been tightened correctly. Experienced locksmiths recommend tightening bolts (nuts diagonally).

After that, tighten the cylinder head completely, and the motor can be operated. The torque wrench is set to the maximum position required by the repair manual for this vehicle.

Important! After clicks, during the final tightening, pull the bolts (nuts) no further! This will break the threads.

After tightening the cylinder head, let it "settle". In order not to waste time, you can fasten the collector and other equipment removed during disassembly for now, tighten the chain, etc. After waiting 30-40 minutes, take a test puff.

The fact is that the gasket, which is placed between the cylinder head and the engine block itself, has the property of "shrinking", that is, filling irregularities and grooves that are on the surfaces of the cylinder head and the block, although they are not visible to the naked eye. If the test tightening is ignored, then in the near future the gasket will "push through", and the engine repair will have to be repeated.