How to determine when to change the timing belt and chain. When do you need to change the timing chain and what is a sign of the need to replace? How often the timing chain changes

Many car enthusiasts like to arrange disputes among themselves about. To establish the truth, you need to know what advantages the chain has in the engine, the disadvantages of the chain, as well as what it is for and what design features the chain drive has.

Read in this article

Materiel

In a car engine, a metal chain is used in one unit: c. To understand its purpose, it is worth remembering the operation of the mechanism itself.

So, during the operation of the internal combustion engine for many, the fuel-air mixture enters the cylinders through. The combustion chamber is separate from the manifold. After combustion, the exhaust gases are removed through, which also separates the cylinder from the manifold. The valves are closed by the valve springs. And they open under the influence of cams.

The cams are located on the shaft axis in such a way as to open some valves while others are closed. The position of the cams relative to the valves changes when the camshaft rotates. In turn, it rotates through. Therefore, it is necessary to somehow transfer rotation from one shaft to another.

The circuit in the engine fulfills this function. The chain has been replaced on many makes and models of machines. It is quite rare to find a hybrid drive in which a chain and a belt are installed at the same time. In addition, the drive can additionally consist of several gears.

The chain drive on the gas distribution mechanism has been used for a long time and is not at all a relic of the past, as inexperienced motorists mistakenly believe. The solution is still used today by such giants of the automotive industry as BMW, Toyota, Mitsubishi and many others. This is due to the following advantages:

Strength. The chain rarely gets mechanical damage;
Wear resistance. With proper care, the timing chain resource is from 100 to 200 thousand kilometers;
The chain life is not affected by low or high temperatures;
The chain does not stretch under load (chain stretching occurs, but only over time, as the resource is depleted);
Resistance to local sudden overloads;

Disadvantages of the timing chain drive

Increased weight. In some cases, this point will seem controversial, and sometimes weight does matter. For example, in racing cars.
The complexity of the design, more technological and costly production. That is, the higher cost of the spare part for the end user. In addition, the design of the entire timing drive itself becomes more complicated, since a damper, a chain tensioner is needed. These parts also fail and often create additional problems.

Difficulty of replacement. In order to replace or at least check the circuit in the car engine, you will have to remove a special cover on, the cover of the block itself (depending on the make and model of the car).

Some motorists cannot or do not want to perform these operations on their own, as a result they are forced to spend additional money in car services. In addition, when replacing, it will be necessary to correctly set the position of the crankshaft and camshaft, which adds to the hassle.

Noise. Even a new chain will make more noise when the engine is running than a belt.

How to understand when it is time to change the chain in the engine

The timing chain, despite its durability, also has to be changed. Most often this happens due to the fact that it is stretched.

That is, its length increases by several millimeters. As a result, the tension deteriorates, the chain often jumps by 1-2 teeth of the gear. All this can lead to extremely negative consequences. For example, a seized engine.

The most alarming signal that will attract the attention of even an inexperienced driver is the characteristic noise emitted by a stretched chain: the rattling and rubbing sound of the chain. This is audible even considering the general noise during engine operation. In this case, it is even possible that the engine stalls, since the chain jumps by 1-2 teeth and the gas distribution is disrupted.

But, it goes without saying that it is better not to bring to such symptoms, but to regularly check the chain tension. You can also focus on the mileage. A chain for an engine of one type or another has a certain average resource (depending on the model and brand of the car). As a rule, this is an indicator of 100 thousand kilometers. To calm your conscience, you can check or replace the timing chain earlier. For example, after 60-80 thousand km.

Why don't some manufacturers supply the chain?

Right now, the question seems to be hanging - why some manufacturers do not install them, but make belts? It's not practical, is it?

There are several answers:

This is noise. Whatever one may say, but even a perfectly tuned motor with a chain is still noisier than with a belt. Well, try to roll metal and rubber links on the asphalt yourself - you will understand what is noisier.

Design feature. The fact is that some engines, for the sake of silence, cannot use their "metal brother", because the belt drive is located outside the engine, that is, it rotates in the air. And so just taking and fixing the metal links will not work.
It is believed that the belt better grips the gears of the shafts, both camshaft and crankshaft. After all, the gear really has wide strips for engagement, but the chain has teeth, and even in oil! No, of course, they are also very effective in engaging the toe, and usually there are two rows of them. But as some manufacturers assure, they can jump over a tooth much faster than a belt.

Well, and actually the last one - tension. It is more difficult to tighten the chain mechanism than the belt. After all, the belt bends easily, and it is, again, in the air. But the opponent is inside in oil, and it is more difficult to pull it up - you cannot bend it properly!

Some write that it is also more difficult to change the chain mechanism, because you really need to disassemble almost half of the engine, but at the belt drive, I unscrewed the casing, removed and quickly put another one on! There is some truth in this, but in any case you will change the belt more often than the chain.

About engine maintenance

To begin with, I would like to say that the condition of the oil greatly affects the resource of the chain. It is inside, therefore, the better it is lubricated, the more the resource will grow. Also, indirectly, frequent replacement takes away from the engine any debris such as sand, dirt, etc., which breaks and wears out the chain mechanism, because sand can penetrate anywhere, including the connecting links. The new oil makes the pistons slide better, which relieves unnecessary stress on the chain mechanism.

In general, the result is this - in order to increase the resource, you just need to change the oil more often, at least by 1000 kilometers, but ahead of schedule. That is, the dealer claims 15,000 - change after 13 - 14,000, and ideally after 10,000, then the chain will last much longer.

Conventional engines

You know, I caught myself thinking that nowhere is there information about how long it takes to change the chain mechanism. That is, if you take a regular car with a conventional naturally aspirated engine (not a turbo - more about that below), the resource is often not limited by the manufacturer!

However, you can find information like this:

After a long mileage, about 150-200,000 kilometers, it is worth listening attentively to the operation of the engine, whether there is excessive beating and noise. If it manifests itself, you need to diagnose the circuit and, if necessary, change it.

That is, the main diagnostics for sound, and not after a certain mileage. Therefore, the resource differs from manufacturer to manufacturer, and from owner to owner.

However, if you knock out the numbers, it turns out:

Taking into account long maintenance (about 15,000 and more)

The chain serves about 150 - 170,000 kilometers.

Taking into account short maintenance (approximately 10-13000 km)

The chain can travel 300 to 350,000 kilometers.

If you take care of the car, then the chain mechanism is really the last thing you change! But wait, my friend changed in 15 - 20,000, what's the catch? YES, nothing, just your friend has an engine from VOLKSWAGEN, that is, a turbocharged, and even weak, volume of 1.2 - 1.4 liters.

Turbocharged engines

Quite different laws work here, turbocharged engines have much more torque and effort, respectively, more horsepower!

Therefore, it is not surprising that the chain mechanism has much less resource, the chain simply stretches here. Then it jumps to the tooth - the engine does not work normally - it consumes a lot of fuel, starts triplet, does not pull, or does not start at all.

Moreover, it manifests itself on weak engines, for example, such as 1.2 - 1.4 TSI. There was a constructive error, the width of the metal is dense - narrow.

Now think about the numbers with which VAG delighted the owners (albeit unofficially):

1.2 TSI engine - replacement after 30,000

1.4 TSI engine (122 HP) - 80,000

Engine 1.8 - 2.0 TSI - 120,000

That is, to call such races large - the language does not turn! However, just imagine how the timing belt would work in such conditions, in general, would it wear out after 10,000?

If you sum up the average figures for turbo engines:

The chain resource is about 120 - 150,000 kilometers. However, you need to read the maintenance regulations, some manufacturers have them strictly prescribed.

"I own a 2008 Honda Civic Hybrid. At the moment, the mileage is 195,000 km. The car has a timing chain mechanism, which does not require maintenance according to the manual. to a mileage of 200,000 km. So far, I have not seen any signs of a malfunction: no extraneous clanking sounds, etc. Is there any diagnostics of the timing chain mechanism? Are there any signs by which we can say about the need to replace the chain? replacing the chain just when a certain mileage is reached, as is the case with the timing belt?

The fact that, according to the factory instructions, the timing chain mechanism in the Honda Civic Hybrid engine does not require maintenance, does not mean that it is eternal and will never need to be replaced. Any mechanism wears out from work, and in the case of a chain, wear in the links of the links, multiplied by the number of links, causes elongation, or, as it is often called, stretching of the chain.

Until a certain time, the tension of the chain is compensated by the tensioner, which takes up the slack in one of the branches, but its rod cannot extend indefinitely. And the limiting position of the rod is, perhaps, the only sign of critical chain stretching, even to a layman, understandable during visual diagnostics of the timing mechanism without removing the chain. Further, the chain, which in principle should already be replaced by this time, requires immediate replacement, because the chain will continue to stretch in length, and the tensioner is no longer able to fulfill its task.

What consequences can the situation lead to when the stroke of the tensioner rod is completely selected, we described in detail in the article, which we recommend to read.

When the chain is stretched, the valve timing is violated. Experts answer in the affirmative to the possibility of detecting phase disturbances using computer diagnostics, but they warn that the chain will not necessarily be the unambiguous culprit.

If the phases are violated, fuel consumption may increase, however, since this parameter significantly depends on the driving style and operating conditions, and the process of chain wear is slow, the driver must have an idea of what fuel consumption was under similar conditions when the car was still practically new. And there are many culprits for the increased consumption, and the chain in their list is far from in the first place, which is why, in this case, there is no need to talk about an unambiguous indication of the chain.

Extraneous sounds from the timing drive can signal problems with the chain, but there are also nuances here. Firstly, the sounds can be short-lived only at the moment the engine is started, while the oil pump has not yet created sufficient oil pressure in the lubrication system for normal operation of the tensioner. Secondly, there are many cases when a worn-out chain jumped over the teeth of the sprockets, without first warning of an impending catastrophe with extraneous sounds and some other external signs.

There are engines in which it is advisable to start checking the timing chain, and, if necessary, change it long before the run named in the question sent, but the chain in the 1.3-liter Civic Hybrid engine, according to experts, is very durable and can withstand 200 thousand km ... However, how much she is still able to serve, no one undertook to predict. Thus, after the specified mileage, the owner of the Civic Hybrid will have to choose what to do - continue to drive at your own peril and risk, check the condition of the chain yourself or turn to knowledgeable specialists for help, or not hope at all, pay a "tax" on reliability and sleep calmly, without a shadow of doubt, replacing the chain according to the run, as is the case with the timing belt.

Price pulse

However, what is the price of peace of mind? The analysis shows that in our market, chains for the Civic Hybrid engine are offered at a price of 86 rubles.

It should also be borne in mind that in addition to the chain, the drive sprockets and tensioner and damper shoes in contact with it wear out, and for complete confidence that nothing extraordinary will happen during the subsequent run until the new revision of the timing drive, it is also necessary to replace the tensioner, on the performance of which much depends. The set costs from 220 rubles.

The desire not to change the original parts that were installed at the factory is understandable. It is not clear what prevents you from using original spare parts and installing them correctly? Of course, it will be more expensive than using a "non-original", albeit of the highest quality. For example, an original chain is unlikely to cost less than $ 100.

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In the engines of the classic Zhiguli series VAZ 2101-2107, the gas distribution mechanism (timing) is driven by a double-row chain. The service life of the part is quite long and amounts to at least 100 thousand km of run. If symptoms of critical wear appear, it is advisable to replace the chain drive entirely, along with the gears. The procedure is time consuming, but simple, a skilled car enthusiast will cope with the task without any problems.

Drive design at a glance

In order to independently change the chain and related elements, you need to know the structure of this part of the power unit. The mechanism that drives the camshaft of the VAZ 2106 engine includes the following parts:

a small drive sprocket is mounted on the crankshaft;
large idler gear;
the upper large gear is bolted to the end of the camshaft with a bolt;
double-row timing chain;
tensioner shoe, supported by a plunger rod;
damper - a metal plate with a wear-resistant pad;
chain runout pin is installed next to the lower sprocket.

In older versions of the "six", a mechanical tensioner plunger was installed, where the rod is extended under the influence of a spring. The updated modification of the car is equipped with a hydraulic plunger device.

During engine operation, the timing chain must be in a taut state, otherwise runout, accelerated wear and skipping of the links over the teeth of the gears will occur. A semicircular shoe is responsible for the tension, supporting the part on the left side.

After the camshaft sprocket (in the direction of rotation), a damper plate is installed, pressed against the chain drive. To prevent the element from jumping off the lower gear as a result of strong stretching, a limiter is installed next to it - a metal rod screwed into the cylinder block.

The drive mechanism is located at the front end of the engine and is closed by an aluminum cover, in which the front crankshaft oil seal is installed. The lower plane of the cover is adjacent to the oil pan - this feature must be taken into account when disassembling the unit.

Purpose and characteristics of the circuit

The timing drive mechanism of the VAZ 2106 motor solves 3 problems:

Rotates the camshaft, opening the intake and exhaust valves in the cylinder head.
It drives the oil pump by means of an intermediate sprocket.
Transmits rotation to the distributor shaft - distributor.

The length and number of links of the main drive element - the chain - depends on the type of power unit. On the "sixth" models of "Zhiguli", the manufacturer installed 3 types of engines with a working volume of 1.3, 1.5 and 1.6 liters. In the VAZ 21063 engine (1.3 l), the piston stroke length is 66 mm, on modifications 21061 (1.5 l) and 2106 (1.6 l) - 80 mm.

Accordingly, two sizes of chains are used on power units with different displacement:

1.3 liter engine (VAZ 21063) - 114 links;
motors 1.5-1.6 liters (VAZ 21061, 2106) - 116 links.

How to check the chain length at the time of purchase without recounting the links? Pull it out to its full length, placing both pieces close to each other. If both ends look the same, this is a 116 link part for long stroke engines (1.5-1.6L). On a short chain for a VAZ 21063, one extreme link will turn at a different angle.

Signs of critical wear on a part

During operation, the car is slowly stretched. Deformation of metal joints does not occur - the reason for the phenomenon lies in the abrasion of the hinges of each link, the formation of gaps and backlash. Within 1-2 bushings, the output is small, but multiply the gap by 116 and you will get a noticeable elongation of the element as a whole.

How to determine the malfunction and the degree of deterioration of the chain:

Once, in the process of diagnosing the "six" motor, I had to observe the following picture: the lengthened chain not only broke the damper, but also made a deep groove in the cylinder head housing. The defect partially affected the valve cover contact plane, but no cracks or leaks of engine oil were formed.

A chain stretched by 1 cm or more is capable of jumping 1-4 links along the gears. If the element "jumped" one section, the valve timing is violated - the motor vibrates strongly in all operating modes, significantly loses power and often stalls. A clear symptom is shots into the carburetor or exhaust pipe. Attempts to adjust the ignition and adjust the fuel supply are useless - the "shaking" of the engine does not stop.

When the chain moves 2-4 teeth, the power unit stalls and will no longer start. The worst-case scenario is a piston hitting the valve discs due to a large valve timing shift. Consequences - disassembly and expensive motor repair.

Video: determining the degree of wear of timing gears

Replacement instructions

To install a new chain drive, you need to purchase a set of spare parts and consumables:

double-row chain, suitable for a specific type of engine;
3 gears - two large and one small (sold as a set);
tensioner shoe;
damper plate;
power unit front cover gasket;
high temperature silicone sealant.

If, when diagnosing a problem, you find oil drips under the crankshaft pulley, you should purchase a new oil seal built into the front cover. The part is easy to change during the disassembly of the timing drive.

for a long period, while the chain was stretched, the teeth of the sprockets also had time to wear out;
for the same reason, the damper and tensioner linings were worn out;
the repair operation is very time consuming, it is impractical to repeat it because of each worn out drive element.

Tool and conditions of work

Of the special tools, you will need a 36 mm box wrench to unscrew the nut (ratchet) holding the crankshaft pulley. Since the ratchet is recessed, it is much more difficult to grip it with an open-end wrench.

The rest of the toolbox looks like this:

a set of open-end wrenches and sockets with a ratchet and a crank;
flat screwdrivers - regular and reinforced;
mounting blade;
pliers;
hammer;
rags, protective gloves.

It is most convenient to replace the timing chain on a viewing ditch in a garage. In an extreme case, an open area is suitable, but then you will have to lie down on the ground under the car to disassemble the unit.

Preliminary disassembly

The purpose of the preparatory stage is to provide easy access to the front cover of the power unit and the timing drive. What needs to be done:

Place the car on the inspection hole and turn on the handbrake. For ease of disassembly, allow the engine to cool down to 40-50 ° C.
Go down into the ditch and remove the sump guard. Immediately unscrew the 3 front bolts connecting the pallet to the end cover, loosen the nut on the bottom generator mounting.
Open the hood and remove the air filter box attached to the carburetor.
Disconnect the tubing over the valve cover. Disconnect the starter drive cable (in common people - suction) and accelerator thrust.
Dismantle the valve cover by unscrewing the fastening bolts with a 10 mm wrench.
Disconnect the electrical cooling fan connector.
Loosen and unscrew the 3 bolts holding the electric fan to the main radiator, pull the unit out of the opening.
Use a spanner wrench to unscrew the nut on the generator mounting bracket. Using a pry bar, slide the housing towards the engine, loosen and remove the drive belt.

In addition to the parts listed, you can remove other items such as the battery and main radiator. These steps are optional, but will help increase access to the chain mechanism.

Disassembly of the injector "six" is carried out in the same way, only together with the air filter housing it is necessary to dismantle the corrugated pipe leading to the throttle, the crankcase ventilation pipes and the adsorber.

Video: removing the electric fan and radiator VAZ 2106

Removing and installing a new chain

If this is your first time disassembling a camshaft chain drive, strictly adhere to the sequence of work:

Unscrew the ratchet nut with a 36 mm wrench. To loosen, fix the pulley in any convenient way - with a mounting spade, a powerful screwdriver, or a pipe wrench.
Remove the pulley from the crankshaft by prying from different sides with a flat screwdriver.
Remove the 9 front cover bolts using a 10mm wrench. Use a screwdriver to separate it from the mounting flange and set it aside.
Bend back the edges of the lock washers on the bolts of the two large sprockets. Grasping the flats on the end of the crankshaft with a wrench and keeping the mechanism from rotating, loosen these bolts with another 17 mm wrench.
Align the notch on the top gear with the lip on the camshaft bed.
Dismantle the damper and the tensioner plunger by unscrewing 2 each 10 mm wrench fixing screws.
Finally unscrew the bolts and remove both sprockets by carefully lowering the chain down.
Unscrew the stopper, remove the chain and small lower gear without losing the keys. Unscrew the tensioner shoe.

During the disassembly process, you may encounter a situation when the chain stretched over the norm has destroyed or cut the damper, and the debris fell into the crankcase. Ideally, they should be removed by dismantling the pallet. But since the oil pump is equipped with a screen, and waste always accumulates in the crankcase, the problem is not critical. There is almost no chance of residual parts interfering with the oil intake.

When replacing the chain on my father's "six" I managed to drop a piece of plastic damper into the crankcase. Attempts to retrieve through a narrow opening were unsuccessful, the debris remained in the pallet. Result: after the repair, my father drove more than 20 thousand km and changed the oil, the plastic is in the crankcase to this day.

Installation of new parts and assembly is carried out in the following order:

Clean the mating surfaces of the cover and cylinder block by covering the crankcase with a rag.
Lower the new chain into the cylinder head opening and secure with a pry bar to prevent it from falling.
Since you aligned all the marks before removing the chain, the keyway on the crankshaft should be opposite the mark on the block wall. Fit the small sprocket carefully and slide on the chain.
Install a new damper, stop pin, and tensioner shoe. Bolt the intermediate and upper gear with a chain.
Install the plunger and use the spring mechanism to tension the chain drive. Check the position of all marks.
Apply sealant to the cylinder block flange and screw on the cover with the gasket.

Further assembly is carried out in the reverse order. After attaching the pulley, it is recommended to re-check that the marks are in the correct position. The notch on the bead of the pulley should face the long strip on the front cover.

Video: how to properly change the chain on a VAZ 2101-07

Is it possible to shorten an extended chain

Theoretically, such an operation is quite possible - it is enough to knock out the cotter pin of one or more links and reconnect the chain. Why such repairs are very rarely practiced:

It is difficult to assess the degree of elongation of the element and the number of links removed.
There is a high probability that after the operation the marks will no longer be aligned by 5-10 mm.
The worn-out chain will definitely continue to stretch and will soon start rattling again.
The worn gear teeth will allow the links to jump easily when the chain is pulled out again.

Economic expediency plays an important role. A set of parts is not so expensive as to waste time and effort trying to repair the part by shortening it.

Replacing the timing chain drive will take an experienced craftsman approximately 2-3 hours. An ordinary car enthusiast will need twice as long without taking into account unforeseen breakdowns. Set aside a part of the day off for repairs and get the job done without rushing. Do not forget to match the marks before starting the engine and make sure that the mechanism is assembled correctly.

The car owner periodically encounters breakdowns. Some can be eliminated quickly, while others will have to tinker. The problem we are going to talk about today belongs to the second category. In order to change the timing chain, serious technical skills are required. But this does not mean at all that independent replacement is impossible.

Reasons for replacing the timing chain

It must be replaced in two cases:

In the event of a break.
In case of severe sprain.

An open circuit is an emergency. If this happened on the fly, all valves in the engine are almost guaranteed to be damaged. They will have to be changed along with the chain, and replacement (with preliminary lapping) will require specialist intervention and will cost the car owner a lot.

Chain stretching is much more common. As a rule, it is associated with the so-called metal fatigue. Usually the chain stretches slightly after 200-300 thousand kilometers (but this only applies to original, high-quality chains from the car manufacturer, lower-quality chains can stretch even after 80-100 thousand kilometers). Stretching leads to a violation of the coordination between the camshaft and crankshaft, which in turn affects the operation of the entire motor. It becomes unstable, at low revs the engine loses throttle response, jerks appear when starting off, etc.

How to determine wear

the most reliable way is computer diagnostics. The car is sent to a car service, installed on a special stand, and the program accurately determines the degree of desynchronization between the crankshaft and the camshaft, after which the car owner receives a graph of the torques of these shafts, for clarity. This method is especially relevant for those who buy a car from hands. It's no secret that unscrupulous sellers often twist the mileage counters on cars, assuring buyers that the car has passed quite a bit. Their motives are clear: twisting the mileage is much easier than changing a stretched part;
second sign of wear: the P0355 code is constantly on on the control panel. The instructions say that it appears when the crankshaft sensor is faulty. But in practice, this may mean that an unscrupulous seller changed this sensor (or even the entire control unit) before the sale in order to mask another error, and the stretched chain did not go anywhere;
third sign of wear: extended tensioner rod. To look at it, the car owner will have to remove the front engine cover. If the tensioner has moved 8-10 mm from its original position, the chain is stretched and must be replaced;

Choice: which spare part is better

There can be only one advice here: you need to buy a spare part produced by the car manufacturer. And this should be done only in specialized service centers. You should never rely on third party products. Because this is a too critical engine part, problems with which can lead either to very expensive repairs or to complete failure of the engine. Yes, branded chains are expensive. However, this is not a spare part that should be saved on.

Timing chain replacement procedure

Before changing the chain, you should decide on the tools that you need for this.

Tools and supplies

New chain from the car manufacturer.
Open-end wrench set.
A set of spanner keys.
Flat blade screwdriver.
Hammer.
Chisel.
Mounting blade.
A piece of wire (diameter 0.5 cm, length 30 cm).

Replacement Sequence

The machine is put into neutral. The front cover is removed from the machine engine to provide access to shafts and gears.
The crankshaft is manually rotated until the mark on the camshaft sprocket matches the mark on the engine housing. There is also a mark on the crankshaft itself. And it must also match the mark on the case.
The marks installed on the camshaft and the timing case must completely match
The lock washer, located under the camshaft sprocket bolt, is gently unbent with a chisel and hammer.
The camshaft lock washer is unbent with a chisel and hammer
The car is now set to the fourth speed, after which the handbrake is applied.
Use a spanner wrench to loosen the camshaft sprocket mounting bolt.
The nut on the camshaft is loosened with a spanner wrench by 17
After that, the timing chain damper is unscrewed and removed (it is most convenient to remove it with a hook from the wire):
The chain guide can be removed and removed with a wire hook
Next, the tensioner shoe is removed (it is indicated in the photo with the number 1). To do this, bolt 2 is completely unscrewed with a 14 open-end wrench, after which the shoe, together with the tensioner, is removed from the engine:
The tensioner shoe is marked in the photo with the number 1, the bolt that holds it - with the number 2
Now the sprocket of auxiliary units is unscrewed with a spanner wrench, but not completely. It weakens slightly, but remains on its shaft.
Helper sprocket is weakened but not removed
As the chain is loose, the chain hooks into the wire hook and is removed from the engine:
The old timing chain is retrieved with a wire hook
The new part fits over the previously removed camshaft sprocket. And only after that the asterisk is set in place:
The new chain slides over the camshaft sprocket, which is then installed in the engine.
After that, it is checked whether the marks on the sprockets and shafts match, if not, the neutral gear is switched on, and the crankshaft is manually scrolled until the match. After that, the bolt on the camshaft sprocket is profitable (but in no case is it tightened).
Now the chain damper and the tensioner shoe are installed in their original place.
Then the nuts on the sprockets of the two shafts are tightened, after which the crankshaft is turned 3-4 times. In this case, the coincidence of the marks on the asterisks and the body is monitored. If there are no discrepancies, the new spare part is abundantly lubricated with engine oil, after which the front engine cover is installed in its original place.

Video: DIY chain installation

Replacing the timing chain is a complex process. Even with experienced craftsmen, it takes 5 hours. A car owner who decides to carry out this procedure on his own must clearly understand what he is doing, since the consequences of improper repairs can be very serious. Particular attention should be paid to the correct placement of the marks. Perfect match and perfect synchronicity must be achieved, because without this the replacement cannot be considered successful.