Gas distribution mechanism

In the engines, a 16-valve gas distribution mechanism with two camshafts located in the cylinder head are applied. The shaft drive is carried out from the crankshaft of the belt transmission.

The head of the cylinder is cast from aluminum alloy, has four valves per cylinder; Hemispheric combustion chambers. The saddles and guide sleeves of the valves are pressed into the cylinder head. The housing of the camshaft bearings are processed in one integer with the head of the cylinder block and have removable covers. The correct position of the head on the cylinder block is fixed by two installation sleeves.

Fig.5

The gas distribution system is designed to provide the supply of an air-fuel mixture into the cylinders and output from the exhaust gas cylinders. All these functions are implemented due to the valve operation.

The valve is in a closed state under the action of the spring, and opens after pressing the rod. The spring is fixed on the rod with the help of superstrears and a special plates. Valve springs have strictly designated rigidity, allowing the valve very quickly during operation. To protect against resonant oscillations on the valves, several springs can be located with a different navill.

Fig.6.

The toothed belt is installed on the pulley of the crankshaft and the camshaft by tags.

Fig.7.

Lubrication system

This engine uses a lubrication system with full-flow oil and oil supply under the phenomenon to the main moving parts and engine nodes. The lubrication system includes: Oil pallet, oil pump, oil filter and different elements that provide oil supply to various motion engine parts. The oil from the pallet through the butter pump is injected into the oil filter.

After passing the oil filter, the oil is part of the oil along various channels in the cylinder block and through the holes is supplied to the native crankshaft bearings. By drills in the crankshaft, the oil enters the connecting rod crankshaft bearings. Lubrication of the walls of the cylinders and the bottom of the bottom of the pistons is carried out mainly by spraying. To lubricate the piston finger in the piston head of the rod and in the piston finger sleeve, a special hole is provided.

Some of the oil after passing the oil filter by drills in the cylinder block is sent to the cylinder head for lubrication:

Driven gear camshaft inlet valves;

Support necks of switchgears;

Cams;

Valve pushers and valve rods;

The leading gear of the camshaft of exhaust valves.

After performing its functions, oil under the action of gravity (samoter) returns to the pallet. To control the oil level in the crankcase, the measuring probe is installed.

Oil pump

Oil pump through an oil truck takes oil from the engine pallet and supplies it under pressure to various friction nodes. A mesh filter oil washed before the inlet nozzle of the oil pump. The oil pump itself belongs to the Trochoid type knasos.

Fig.8.

Inside its arranged Ivyvanovy Rotors with internally labeled, which rotate the water direction. Since wringing and driven rotors are displaced by another friend, spaces between both rotors change as they turn. The oil is suused by the VNSOS, when the space between rotors is rotated, and is injected, when the sprout between the rotors is narrowed.

Oil pressure regulator (reducing valve)

At high speeds of rotation, the amount of oil supplied by the oilosos is redundantly compared to its quantity necessary for lubricating rubbing steam. Oil pressure regulator (reduction valve) prevents excess oil supply. At low rotation frequencies, the valve of the regulator under the action of the spring overlaps the bypass channel. But at high speeds of rotation, the oil pressure increases sharply, the oil pressure force overcomes the spring force, and the valve of the regulator opens. Excess oil through the valve returns to the pallet.

Fig.9.

Oil filter - full-flow type with a replaceable paper filtering element. Metal particles (wear products), dirt particles, in the air, Nagar particles and other contamination particles can fall into oil in the process of use, which leads to an increase in engine wear or clogging (narrowing channels) of oil pipelines, preventing oil circulation. The oil filter mounted in the oil line allows you to delay these particles when the oil is passed through it. The filter is installed on the outer side of the engine, which allows you to relatively simply replace the filter element. The filtering element is installed with a bypass valve, which opens with an increase in pressure in front of the filter arising in the case of clogging the filtering element with polluting particles. The bypass valve opens when the oil pressure force exceeds the valve springs force. In this case, the oil passes through the bypass canal, bypassing the oil filter, and is directed directly to the engine's main oil housing line.

Selection of viscosity engine oil (SAE).

The oil is selected according to the temperature range diagram corresponding to the operating conditions of the car until the next oil change.

Fig.10.

Monitoring the level of engine oil. Refueling capacity: with a filter replacement - 2.7l., Dry motor - 2.9 liters.

Fig.11 Oil level on SchUP.

The car owner periodically faces breakdowns. Some can be eliminated quickly, with others you have to tinker. The problem of which will be speaking today, refers to the second category. In order to change the timing chain, you will need serious technical skills. But this does not mean that independent replacement is non-profit.

Causes of the replacement of the chain of the gas distribution mechanism

It is subject to replacement in two cases:

1. In case of cliff.
2. In case of serious stretching.

Chain break is an emergency. If this happened on the go, all valves will be damaged in the engine almost guaranteed. They will have to be changed along with the chain, and the replacement (with the preliminary witch) will require the intervention of specialists and will cost the car owner very expensive.

The stretching of the chain is occurring much more often. As a rule, it is associated with the so-called metal fatigue. Typically, the chain is slightly stretched through 200-300 thousand km of mileage (but this applies only to the original, high-quality chains from the car manufacturer, less high-quality chains can be stretched through 80-100 thousand kilometers). Stretching leads to a violation of coherence in the work of the camshaft and crankshaft, which in turn affects the work of the entire motor. It becomes unstable, on small speeds, the engine loses her riser, jerks appear when touching from the place, etc.

How to determine wear

• the most reliable way is computer diagnostics. The car goes to the car service, is installed on a special stand, and the program accurately determines the degree of distance between the crankshaft and the camshaft, after which the car owner receives a graph of torque of these shafts, for clarity. This method is especially relevant for those who acquire a car with hands. It is no secret that unscrupulous sellers often twist the run meters on the machines, assuring buyers that the car has passed quite a bit. Their motifs are understandable: twist the kilometer is much simpler than to change the stretched part;
• second sign of wear: An error P0355 is constantly on the control panel. In the instructions it is written that it appears when the crankshaft sensor is faulty. But in practice, this may mean that the unscrupulous seller before selling has changed this sensor (or even the entire control unit) to mask another error, and the stretched chain is not doing anywhere;
• third sign of wear: advanced tensioner rod. To see it, the car owner will have to remove the front cover of the engine. If the tensioner moved 8-10 mm from its initial position - the chain is stretched, and it must be replaced;

Choice: what a spare part is better

Here the Council can only be one: it is necessary to buy a spare part released by the car manufacturer. And it is necessary to do this only in specialized service centers. In no case should not rely on products of third-party suppliers. Because it is too responsible engine detail, problems with which can lead either to a very expensive repair, or to the complete outlet of the motor. Yes, branded chains are expensive. Nevertheless, this is not the spare part on which to save.

Procedure for replacing the timing chain

Before changing the chain, you should decide on the tools that will be needed for this.

Tools and consumables

1. New chain from the car manufacturer.
2. Set of horn keys.
3. Set of attic keys.
4. Shutter with flat sting.
5. A hammer.
6. Chisel.
7. Mounting blade.
8. Cut wire (diameter 0.5 cm, length 30 cm).

Sequence of actions when replacing

1. The machine is installed on a neutral transmission. From the engine of the machine, the front cover is removed to provide access to shafts and gears.
2. The crankshaft manually turns until the label on the stack of camshaft does not coincide with the label on the engine housing. On the crankshaft itself there is also a label. And she should also coincide with the label on the housing.

   

   Tags installed on the camshaft and the GDM body must completely coincide.

3. The lock washer installed under the bolt of the stars of the camshaft, neatly extension with the help of a chisel and hammer.

   

   The locking washer camshaft is elegted with a chisel and hammer

4. Now the car is installed on the fourth speed, after which the handbrake is turned on.
5. The fastening bolt of the camshafts of the camshaft is weakened by the key.

   

   The nut on the camshaft is weakened by the on-line key on 17

6. After that, the timing of the timing chain is unscrewed and extracted (it is most convenient to remove it with a wire hook):

   

   Soothing chain is removed and removed by a wire crochet

7. Then the tensioner shoe is removed (it is designated on the photo number 1). For this, the bolt 2 bolt 2 is fully dismissed by the horn key on 14, after which the shoe with the tensioner is removed from the engine:

   

   The tensioner shoe is designated on the photo of a number 1, a bolt that holds it - digit 2

8. Now the starrel of the auxiliary units is unscrewed by the key, but not completely. It is slightly relaxed, but remains on its shaft.

   

   Auxiliary stars weakened, but not removed

9. Since the tension of the chain weakened, it engages with a wire crochet and removed from the engine:

   

   Old timing chain is extracted with a wire hook

10. The new detail is put on the removed starrel of the camshaft. And only after that the stars is installed in place:

    

    The new chain is put on the stars of the camshaft, which is then installed in the engine

11. After that, it is checked, whether the labels on the stars and shafts coincide, if not, the neutral transmission is turned on, and the crankshaft manually scrolls until the coincidence. After that, it is naked (but in no case is not delayed) the bolt on the stars of the camshaft.
12. Now the chain calm and the tension shoe is installed on the regular place.
13. Next, nuts on the stars of two shafts are tightened, after which the crankshaft turns 3-4 times. At the same time, the coincidence of labels on the stars and the case is monitored. If there is no discrepancies - the new parts is abundantly lubricated with engine oil, after which the front cover of the engine is installed on the regular place.

Video: installation chain do it yourself

Replacing the timing chain is a complex process. Even experienced masters, he takes hours 5. The car owner who decided to spend this procedure on his own, should clearly imagine what it does, since the consequences of improper repair can be very serious. Special attention should be paid to the correct location of the labels. It is necessary to achieve perfect coincidence and ideal synchronicity, because without this, the replacement cannot be considered successful.

The strap of the gas distribution mechanism is one of the most important parts of the car: when the breakage will stop the timely supply of the working mixture and the removal of spent gases. In case of damage to the valves of expensive overhaul of the motor can not be avoided.

If the car is used, then you should not wait for a time to replace the passport.

When to change the timing belt and why there is a break - in the material "AIF-Chelyabinsk".

Toothed rim

Externally, the timing belt is a rubber gear rim. With the longitudinal arrangement of the engine, this part is between the engine cylinder block and the radiator. In the transverse, as a rule, on the right side (from the opposite side of the gearbox).

"Determine when changing the timing belt, with an accuracy of a kilometer is impossible. Not every belt serves as much as the manufacturer measured him. Therefore, once every 3 months should control its external state. It should not have obvious traces of destruction - microcracks and detachalies. It is important that the belt is always in a stretched state. You can check it as follows: if it scrolls with your fingers by more than 90 degrees, it means that it must be pulled, but do not drag, "says auto mechanic Andrei Yeremin.

Modern automakers recommend changing the belt every 50-80 thousand mileage kilometers or every 4-5 years. More accurate values \u200b\u200bcan be found in the car operating manual, since each model has its own specific resource. Specialists suggest that it is impossible to install the belt and forget about it for the next 80 thousand kilometers of the mileage. It can break into 10, and 40 thousand, and can serve and longer than the specified period.

Fatigue material

The belt break occurs most often due to the worniness or poor-quality assembly of the product itself.

"There is such a concept as material fatigue. With each day, the timing belt loses its former elasticity, peels off, cracks appear on it. He also rushes due to the jammed pump and stretch rollers. Less frequently, this situation takes place when the encinsing of one or more camshafts, "the car mechanic continues to tell.

Automakers do not release universal belts. They are selected to each machine separately. Experts advise to buy original products that the manufacturer puts. When the belt is cut, the machine will stall, and start the engine will not work.

GRM chain drive

If the timing belt is a rubber tape with teeth, then the chain is already a metal part that is made in the form of roller connectors.

"At one time cars were produced with a chain that could serve for a very long time. But the era of such cars has long ended. Modern machines with chain drive drives are practically also vulnerable as vehicles with belt drive. If the belt is broken, the internal combustion engine is easily saved from overhaul, replacing the part to a new one in a timely manner. If the chain calm is wearing, it threatens with a complete failure. This material is explained by the material that is much massive belt. Chain slippage most often leads to expensive engine repair, because the insides of the motor is damaged, "says the car mechanic.

Pros and cons

1. The chain is not afraid of frosts and heat, dust.
2. Not stretched under load - only with time due to wear.
3. There is no need to seal the device from the engine oil.
4. High accuracy of gas distribution phases.
5. Roller compounds of the chain have less flexibility, no more noisy during rotation.
6. The cost of manufacturing engines with such a drive is higher than the motor with the belt.

On some cars, the chain withstands the entire passport period, it does not withstand 60 thousand kilometers on others. Experts argue that the case in defect - the manufacturer violated the quality standards of lubrication, its abundance.

The chain drive should pay a separate issue of oil replacement. Lubrication should be carried out at least than once every 15 thousand mileage kilometers.

"You need to carefully treat the noises of different kinds, knocks. Especially relevant to pay attention to noises arising immediately after starting the engine or in the process of long-term operation of the engine at idle. It is possible that these are initial signs of the timing fault, "experts advise.

How to determine belt wear and timing chains:

• The appearance of the product - cracks, detachal.
• Deviation from the specified position of the tensioner roller and the stars of the shaft.
• Increased temperature or malfunction of the roller bearing.
• Belt elongation.

• Rough work of a motor at idle.
• Unusual noise, knocks.
• The optimally allowable arrangement of the tensioner is noticeable after removing the protection cover.

The chain drive of the gas distribution mechanism is associated with most motorists with reliability, durability and reliability. Such beliefs are confirmed by practice, although exceptions are also found. On some brands of cars, it is drawn pretty quickly, and sometimes even rushes. If this did not lead to serious consequences, then the owner of the car is completely able to replace the timing chain on its own, although the disassembly procedure is quite long and time consuming.

How to determine the chain drive malfunction

Unlike the timing belt transferred beyond the engine, the chain with gears is located inside the power unit and is completely hidden from the eyes. On the one hand, this is a plus: the mechanism is less than noise and is abundantly lubricated with engine oil, which increases its resource. On the other hand, without removing the valve cover it is impossible to visually evaluate the technical condition of the node.

The first sign of the chain transmission problem is a roofing sound that is coming from under the cover when the power unit is operational. The rake of a weakened chain will not be confused with anything, it is heard from the side where the gas distribution mechanism is located.

Hearing a similar sound, the car owner must check the actuator status in order not to encounter big trouble associated with the repair of the motor. There are 2 ways: immediately go to the diagnosis in the nearest car service, or remove the valve cover on your own and make sure the chain section is ascent near the camshaft gear. The deterioration of tension causes such reasons:

• due to stretching to such a length that the tensioning device is unable to choose a slack;
• due to the fault of the tensioner;
• the sedative plate is worn or torn out;
• due to the large mileage of the car, all parts of the mechanism - a chain, gear, tensioner and a calm was worn.

If a mechanical tensioning device of an old sample is installed in the auto engine, then when described symptoms appeared, the first action is to pull the chain with it. To do this, it is enough to loosel out the outer nut holding the spring of the plunger, and manually turn the crankshaft for 1-2 turns. After that, the nut is tightened again.

Modern hydraulic tensioners of automatic action are not designed for manual adjustment and in case of breakdowns are subject to replacement. Ensure that the element has failed, it is possible only by removing it or disassembling the entire GD assembly. The same applies to the sedative - on most cars, its wear can be estimated only with the disassembled mechanism.

Ignoring the grinding noise published by the chain, sooner or later will lead to a breakdown of the motor. The seriousness of the consequences depends only on your luck.

Consequences of faults

Mercing chain transmission leads to such problems:

1. A stretched and weakened chain jumps into several teeth. As a rule, this happens at the time of engine start.
2. The chain, working with an increased free course, often breaks down the calm and even "breaks out" the groove in the head of the cylinder block made from the aluminum alloy.
3. In some brands of cars, where a single-row chain is applied in the power units, it can occur.

Note. Chain transfer of the timing assembly is one - and double row. The first are not so reliable and durable, as the second, and often break after a run of 50-80 thousand km. Double-row drives are harvested extremely rare, even when the owner of the car does not pay due attention to it.

The consequences of the listed problems may be such:

1. The most harmless option is the shift of the phases of the gas distribution due to the retelling of the chain by 1-2 teeth. The motor is badly started and vibrates greatly when working, the power loss is clearly felt on the go. With a sharp press on the accelerator pedal, the shots in the intake manifold or exhaust pipe are heard.
2. When there is a displacement of 3 tooth, the engine will not be started. Another thing is that in practice such situations are rarely found, too free chain accesses much stronger. The result is a piston piston in the valve that has opened not on time.
3. From strong wear or cliff of the sedator, the chain transmission is relaxing even stronger, which is why the consequences described above are the consequences.
4. The damage to the gap of the single-row chain depends on the type of engine and the moment when it happened. If all valves are closed, then pistons that continue to move will not get to their plates.

In the power units on 8 valves, the meeting with the piston happens quite rarely due to the technological gaps provided for by the design (except for individual motors). But open at the time of the cliff or the circuit of the engine valve 16V almost always gets a blow from the piston. As a result, its rod and the valve remains in the open position. In particularly severe cases, the consequences are:

• even the saddle of the valve and the guide sleeve is damaged;
• through the upper part of the piston, a cross-cutting hole appears;
• on the plane of the cylinder head near the combustion chamber appears, the dent appears, which is why it is necessary to change it entirely.

The chain that cropped or broken on the go makes itself felt a sharp power loss or a complete engine failure. If you managed to hear a metal knock, meaning a piston and valve meeting, then you should prepare for the serious repair of the power unit.

What is the service life of the regulations on the regulations and the frequency of replacement

On average, the timing chain transmission serves from 200 to 350 thousand km of car run. The indicator varies depending on the style of driver driving and the quality of the engine oil used, which are lubricated by the links and gears. It depends on it and the operation of the hydraulic tensioner.

Reference. In cars leading German and Japanese manufacturers, a two-row chain often operates 450-500 thousand km, and even more.

In contrast to German brands, the two-row drives of Korean small-caps from Kia and Hyundai manufacturers are surprisingly not enough. It was often noted that cases of stretching and replacing chains when running 60-90 thousand km on Hyundai Solaris models (in Ukraine - Hyundai Accent) and Kia Ceed, which is comparable to the resource of the timing belt. From here and recommendations for the timing of the chain transfer:

1. On Korean small car, it is necessary to listen and check the condition of the drive starting from 60 thousand km of mileage. With a good outcome, the replacement is performed in the range of 120-150 thousand km.
2. The same applies to the single-row chains installed on many European economy machines, for example, Peugeot, Opel and small diesel engines from Audi.
3. Double-row transmissions of other brand cars should be paid to 150 thousand km after periodically checking their condition. The replacement is made as wear, but on average, no earlier than 200 thousand km.

To avoid troubles related to breakdowns of the GD drive, you need to carefully examine the instructions for the operation of the car and the manufacturer's recommendations for the maintenance of a particular car.

How to choose a new spare parts set

Like other car parts, the timing chains are fake with handicraft and Chinese manufacturers, after which they fall on sale. Clear delints constantly come up with new ways of deception of buyers, for example, laid their poor-quality products in original packaging of famous brands from Western Europe. In order for the details when you buy, do not run into a fake spare part, follow these recommendations:

• buy a chain from official sales representatives, dealers either in stores positively proven themselves among other users;
• do not try to save, considering products of unknown manufacturers;
• check the detail for the presence of labels and deflection in a horizontal position;
• consult with a familiar car mechanic, which brand is better to choose for your car brand;
• make a visual inspection of the product on a careless manufacturer or other signs - burrs, the backlash between the links and so on.

The chain is tested for the deflection: they take it in one end and hold the plafhmy. The second end must be saved no more than 10 mm. If you succeed, then check the toughness of the metal, gently pushing it with supfil. Steel in high-quality products is hardened, and therefore it is characterized by increased hardness and cannot be equipped with a file.

Council. The main technical characteristics of the chain are its size and number of links, on them and need to pick up the item. If you are overcome doubts, do not buy a new spare part without removing the old one with which it can be compared.

If you update the chain transmission with a significant range of cars (150-200 thousand km), you will have to change all the accompanying elements - gears, tensioner and sedative. When the chain stretched out after a run of 50-100 thousand km, then the gear changes are optional, but the tensioning device needs to be checked for performance. Also do not forget to buy consumables - gaskets of covers, sealing rings and heat-resistant sealant.

Replacing the timing chain

The complexity of the procedure is to dismantle the attachments and disassembling the power unit, which takes up to 3 hours. Removing and installing a new drive is quite simple. If you need to replace all the elements, then before performing the work, you must be perfectly inserted into the machine drive device of your car. Example: On the same KIA CEED, the gear applied to the crankshaft under heating, so at home you cannot dismantle it. Then the engine disassembly loses its meaning, because it will be possible to replace one chain.

From special tools You will use the device for fixing camshafts on a 16-valve motor (conductor). The rest of the toolkit is standard:

• a set of horn keys and heads with an extension nozzle;
• jack, wooden stands and balloon key;
• capacity for draining motor lubrication and antifreeze;
• plumbing tools - hammer, dumping, passatia;
• rag.

To work, you will need an observation ditch and a portable lamp (flashlight). Put the front-wheel drive car to the pit in such a way as to provide access to the front wheel from the MRM knot. The rear-wheel drive car is placed as convenient, there the wheels do not have to remove.

Disassembly and removal of stretched chain

The first thing is the following preparatory operations:

• fix the auto with the counter-type;
• disconnect the heating nozzle of the throttle and drain the cooling fluid from the engine shirt;
• in the rear-wheel drive car, you need to empty the radiator;
• merge engine oil;
• dismantle the lower protection of the motor and mudguards that prevent further disassembly;
• disconnect the nozzles and the cable from the gas pedal, which prevents the removal of the valve cover.

Note. It is not always necessary to drain the oil, it depends on the brand of the car. For example, when replacing the chain on the VAZ 2101-07, the lubricant remains safely in the crankcase and does not interfere with the management of work.

In the front-wheel drive, you will have to remove the front wheel from the gas distribution mechanism and opened the car onto a wooden stand. The jack will be needed later, for the lifting of the power unit.

The order of disassembly makes sense to consider on the example of the Korean car Hyundai Solaris 16V, in the other machines with the front-wheel drive, the principle of work is not very different:

Note. When disassembling the rear-wheel drive version, the car does not need to remove the wheel, lift the engine and spin the pillow. Instead, you will need to dismantle the radiator together with the fan.

After disassembly, it is necessary to clean the planting flange of the cylinder block and the lid from the residues of the old gasket and the sealant, and also wipe the flow of oil and coolant. Then by turning the crankshaft to combine all the labels, knocked out on the gears, with risks on the motor housing or other benchmarks specified in the car documentation.

There are 2 ways to weaken the chain for further removal:

• to unscrew 2 bolts of the hydraulic machine and remove it;
• press the latch of the lock in the tensioner, pressed on the plastic shoe and weaken the chain.

After weakening, the chain transmission is freely dismantled manually, the main thing is not to confuse the label position.

Video disassembly mechanism timing

Installing a new part on the engine

Before assembling the mechanism, make sure that you have all the consumables:

• gasket under the timing cover;
• pump gasket;
• new rubber sealing rings;
• new hydraulic machine;
• shoes for tensioner and sedative (if necessary);
• high temperature sealant.

If you need to replace the wear shoes of the tensioner and the calm, it is done before the chain drive assembly. This is not a problem, they are attached to 2-3 bolts (depending on the brand of the machine).

For convenience and error-free installation, manufacturers are often affixed on the links of the label chain, combined with risks on the gears of camshaft and crankshaft. The first two are drawn yellow, third - black or other color. Therefore, the chain is put on the gears taking into account these tags, after which it stretches.

How to change the timing chain correctly: video

How to replace the tensioner

The hydraulic tensioning device is recommended to be changed along with the chain drive. It holds on two bolts that need to be unscrewed to replace the part. The new tensioner is equipped with a check fixing the plunger in the initial state. When the chain is installed on the labels, and its slab is chosen towards the stretch shoe, the check is twisted and the spring pushes the rod by pressing the shoe with the guide. Thus, the chain is stretched.

Note. While the engine is not started and the oil pressure in the system is missing, the chain transmission will be tensioned only with a spring force. Therefore, the stretch will be released too strong.

After installing and adjusting the timing chain drive, turn the crankshaft for 2-3 turns and depart the position of the labels again. Specially lubricate the links of the chain is not necessary, it will happen automatically after the motor start. Then the reverse engine assembly is performed with the installation of new gaskets on the sealant.

How the hydraulic tensioner works: video

The operation of the engine depends on the reliability and durability of the timing chain, so its condition needs to be monitored to replace and avoid deposits. It is equally important to change the engine oil in a timely manner, lubricating the drive and creating additional pressure in the tensioner. When the motor lubricant does not perform the function assigned to it, the chain is pulled out faster, and the dirt interferes with normal operation accumulates in the hydraulic casing.

Typical text of a merchant selling a car with a chain drive timer looks like this: "There is a chain, not a belt. So, it disappears the need to spend time and money on the replacement of the timing belt. Many buyers come across this trick. Ultimately, the chain turns out to be torn, and the engine needs overhaul. Remember: the era of chains that can serve more than a million kilometers, it has long been over with old Mercedes!

The rupture of the timing belt is a serious incident, however, in most cases there is hope to save the engine. A similar situation with the timing chain can end much worse. The chain is a much massive belt and in the event of a break, as a rule, "River and mosques" engine, "Having done with you" whole pieces of metal. In addition, pistons and valves are very damaged. Very rarely after breaking the timing chain, the engine manages to reanimate with low blood.

All thing in oil

The approximate resource of the modern chain is a minimum of 200-250 thousand km. However, it often does not stand so long. Cases of chain breakdown when running 100,000 km, and even 60,000 km. The fact that this happens only with certain models of cars, speaks of congenital defect. And not always the "catastrophe" occurs due to the poor quality of the chain and tensioner. Sometimes the problem is caused by a lack of lubricant. This happened to the first PEUGEOT-CITROEN 1.6 THP (Euro 4) gasoline engines (Euro 4) and a 2-liter Diesel engine BMW (BMW 3 E90, 320D N47).

So, non-compliance with the manufacturer's recommendations regarding the amount, the type of oil and replacement intervals many times increase the likelihood of malfunction. Do not forget that almost every chain is held in tension tensioner, the efficiency of which is directly depends on the pressure in the stroke system. A typical example is a Fiat 1.3 Multijet turbodiesel, which is used in Opel models with 1.3 CDTI. With frequent movements in urban conditions, the oil level is highly dropped. If this is not noticed in time, the pressure in the system, and, consequently, the tension of the chain begins to decline.

But, of course, it does not do without errors in the design of the design of chains themselves and tensioners. A vivid example is the gasoline engines of the concern VW 1.4 TSI and 1.2 TSI.

Terms and symptoms

Most manufacturers do not indicate the hard limits for replacing the timing chains, as in the case of gear belts. Circuit wear is determined by symptoms. As a rule, this is an increased noise and shift phases of gas distribution (detected using a diagnostic computer). Good motorists easily recognize malfunction. Some engines allow you to evaluate the state of the chain to output the string rod.

Buying a used car with a timing chain drive, monitoring the state of the chain should be entrusted with the mechanics. Unlike engines with a belt, you should not be guided by the Rule of Replacement "Just in case". If the inspection shows the need to replace the chain, then you will have to prepare from 500 to several thousand dollars. This is a serious reason to bargain with the auto seller on the secondary market. In any case, the replacement is not worth it.

During the operation of the vehicle with a chain drive of the timing, a pedantry in matters relating to engine oil should be taken. We must only use high-quality oil. Regular replacement is another important element of care not only by the engine, but also the chain drive of the timing. As a rule, the change of lubricant should occur at least once every 15,000 km. If the car is operated mainly in urban traffic conditions (frequent launches, a large proportion of idle work time), then the replacement interval is better to reduce up to 10,000 km.

It is necessary to pay attention to unusual sounds (noise, knock), especially appearing immediately after launching or during long-term work at idle. Finding the characteristic signs of "malaise", it is worth visiting the auto service. Perhaps this is the first symptoms of improper operation of the timing of timing, which cannot be ignored.

Two ways to place the timing chain in the engine

In the engine, two types of timing is used in the engine. Conditionally let's call them front and rear. "Front" when the timing of timber is located on the same side as the drive belt of hinged units. "Rear" when the GDM drive is located on the side of the flywheel and gearbox. Typically, manufacturers use the front arrangement of the timing of the GDM, since with such a scheme it is easier to access and repair the system. However, for several years already have companies such as Audi and BMW, practice the timing of timing timing on the back of the engine: Audi A6 C6 3.0 TDI, BMW 320D E90 (N47), BMW 530 F10. This greatly complicates the maintenance of the timing. Fortunately, such bold solutions are applied only in some motor chain drive, and never apply in engines with a toothed belt.

Timing chain wear symptoms

Coarse and uneven work at idle (the result of changing phases of gas distribution);

Drying and rustling - especially at idle when the oil pressure is very low;

Maximum tensioner output (seen after removal of the lid);

Wear of stars teeth (seen after removal of the lid);

The corresponding parameters removed from the phase sensor (using the diagnostic tester).

What you need to know about the chain drive timing

In most new cars, the chain service life is less than the service life of the engine;

Pay attention to unusual noises, especially after launch;

Avoid an increase in the life of the oil replacement - the more often the better;

Normal oil pressure ensures the operation of the chain tensioner;

If you change the chain, then definitely replace the gears (asterisks) and guides - they also wear out;

When replacing the original components, or high-quality substitutes. Complimentary components such as FEBI, Ruville, SWAG have proven well.

Reliable and unreliable timing timers

However, manufacturers still produce cars with a timing chain that can work out the entire service life of the engine. As a rule, problems with such timing does not occur for several hundred thousand kilometers. However, this does not exempt the owner from responsibility to regularly check the status of the timing chain drive.

Cars with durable chain timing: Ford Mondeo 1.8 TDCI, Mercedes C 200 CDI W202, Mercedes W124, Toyota Yaris 1.4 D-4D.

Cars with a short chain timing: Audi A8 3.0 TDI (D3), Mazda CX-7 2.3 Turbo, Skoda Fabia 1.2 TSI, BMW 118D (N47), Peugeot 207 1.6 THP, VW Golf V 1.4 TSI.