Car owners encountered the problem of valve bending even on the first G8 models. The 1300cc engine installed on them bent the valves when the belt broke.

This problem is associated with several reasons, such as jamming of the pump and tension rollers, wear or poor quality of the timing belt.

When the timing belt breaks camshaft stops in the position in which the break occurred, and crankshaft, continuing to rotate, pushes the pistons towards the open valves. As a result, they collide, leading to damage to the valves and pistons.

Such a collision can damage not only the pistons, but also the cylinder walls and connecting rods. In this case, car repairs will be very expensive and time-consuming.

On some types of VAZ car engines, this was avoided. In such engines, special recesses for the valves are cast on the pistons, so if the belt breaks, a collision does not occur.

Several types of engines were installed on the Lada. Let's look at which of them are dangerous and which are safe and why the valve on Kalina bends when the belt breaks.

Types of engines affected by this problem

1. Eight-valve, model 21116, volume 1.6 liters, equipped with a lightweight piston group. Due to the lightening, the pistons became very thin and there was simply no room left for the valve casting. When such pistons collide with a valve, the entire piston group usually suffers.
2. Sixteen-valve, model 21126, with a volume of 1.6 liters, is installed on the more expensive Kalina class of cars. On this engine, collision of pistons with valves is also inevitable.
3. The sixteen-valve model 11194, with a volume of 1.4 liters, is one of the most economical, but, unfortunately, is also susceptible to this problem.
4. Sixteen-valve, model 21127, volume 1.6 liters. This new engine, created on the basis of the previous model 21126. Installed recently. It is more powerful, but also remains on our “dangerous” list.

Types of engines not affected by this problem

1. Sixteen-valve, model 21124, with a volume of 1.6 liters, is considered one of the most reliable. It was installed on the twelfth model of Lada. With this engine you will not have any problems with the gas distribution mechanism.
2. Eight-valve, model 11183, 1.6-liter, proven engine, distinguished by its reliability, ease of maintenance and availability of spare parts. Also falls into the category of safe.

A few tips on how not to find out if the valves on Kalina are bent and not end up with expensive repairs

In order to try to avoid damage to the gas distribution mechanisms, it is necessary to promptly replace the timing belt.

It is not enough to change one belt. Be sure to change the tension rollers along with it and monitor the condition of the pump. If necessary, it must also be replaced.

Never skimp on spare parts. Choose your timing belt carefully. It should not have any irregularities, stripes or seams.

When purchasing a water pump and tension rollers, choose only well-known and trusted manufacturers.

By observing these simple rules, you will never know whether the valves on a Kalina car are bent, and how much it costs to overhaul the engine.

I would like to hope that this article will help avoid problems, usually associated with oversight technical condition car. With the correct attitude towards the operation of the elements of the gas distribution mechanism, such problems should not arise.

Details Category: News Published 07/27/2018

AVTOVAZ engines will receive a new piston, which will avoid bending of valves when the timing belt breaks.

As you know, one of the disadvantages of modern engines is the bending of valves when the timing belt breaks. It is quite difficult to predict the life of a belt, since it can break not only due to wear, but also if the pump or tension roller is jammed.

When the timing belt breaks, a modern engine usually bends the valves on the pistons. This leads to expensive repairs.

AVTOVAZ decided to eliminate this problem, reports CARscope.ru. The plant's supplier, Federal Mogul, has mastered the production of pistons with special recesses.

Thanks to this shape, both pistons and valves will remain intact even if the timing belt breaks.

The new piston group is designed for a range of engines. It's 8- valve VAZ-11186 with a power of 87 hp. s., as well as 16-valve engines VAZ-21126 (98 hp) and VAZ-21127 (106 hp), which are installed on the Kalina and Grant family of cars.

The 106-horsepower VAZ-21129 engine, intended for the Vesta and XRAY models, should also soon receive a version with new pistons. And here new unit VAZ-21179 with a volume of 1.8 liters and a power of 122 hp. With. until he gets a new piston.

Enough actual question Which VAZ engines do not bend the valves will probably be of interest to every owner of a car from a legendary domestic manufacturer - old or new - without much difference. The fear of a broken belt for some drivers even turns into a kind of paranoia: they begin to carry a spare belt with them, at every opportunity to study the condition of the working one, and consult with all their friends and acquaintances who have at least some connection to the car industry. But can such actions always lead to the planned result?

On which VAZ engines the valves do not bend, you need to know for sure, and this data will strengthen your understanding: will it be necessary to repair, in addition to replacing the belt if it breaks, the engine? After all, this procedure can take a lot of effort and, most importantly, money.

A little history

Remembering engine modifications on models is not particularly difficult. But everything is in order! The first ones had 8-valve engines (1.5 and 1.6 liters). The valves didn't bend on them. And all for a simple reason: pistons in the intended design were not found in the event of an incident with the valves.

The developers pretty well avoided the problem that could arise, honor and praise to them for this (how many people this feature saved from unplanned and quite expensive repairs)! A little later, a new engine at that time.

With all the improvements and increase in quantity Horse power up to 92(from 76), which was a clear plus, this engine also had some, not immediately noticeable, shortcomings. The design of the mechanism has been changed thanks to a new head (16 valves). And as a bonus, the pistons meet the valves in the event of a timing belt break (at the most inopportune moment, as a rule)!

As a result– the valves were definitely bent on this model. And the car owner was in for quite an expensive repair that cost a pretty penny. The reason, in addition to a broken belt, is simple - the very design of the 1.5 liter engine with 16 valves: the pistons do not have special under-valve recesses and, as a result, hit the valves hard. There is a bending of these parts, popularly called: the valve is bent.

Correcting errors: But a few years have passed, and the designers have revised their concept. At 2112 they began to install new 1.6-liter engines, also 16-valve. In these modifications, little changed from the previous ones, but there were recesses for valves on the pistons, which made it possible to avoid the collision of these parts if the belt breaks, and therefore expensive repairs.

All repeats

Not many years have passed, the happy owners of these VAZ models have already begun to get used to good things. Moreover, if the belts break, the valves on the engine do not bend, injuring it from the inside. But it was not there! Domestic auto industry does not allow you to relax even for a minute. On the horizon appears the Priora (updated ten), a seemingly modern car, quite decent for many. Engine - 1.6 liters, 16 valves. Car enthusiasts thought that such annoying flaws would not happen to him.

However, as practice has shown, if the belt breaks on a Priora, the valves still bend (that is, they also meet the pistons, as on the original 16-valve mechanisms). And who, one might ask, needs this: additional repairs that cost a pretty penny in these days? After all, repairing a Priora engine will cost even more expensive than that of an ordinary ten.

One good thing is that the likelihood of such a flaw is still reduced to a minimum by the designers: the belt is much wider and it does not break so often. But sometimes it breaks! Or, for example, a defective spare part may come across, and the likelihood of a break will increase significantly. What to do then? We'll have to repair the engine too, and not just install new belt. Because it is not possible to predict when this might happen if there are hidden defects.

All that remains is to make a wish that this breakdown does not happen somewhere in an open field, where cars do not pass often, but in a city where your car can be towed.

By the way, to Kalina They also install engines similar to the methods of destructive action on valves, only 1.4 liters (16 valves). So, as they say, be vigilant and know: on which VAZ engines the valves do not bend, and on which ones they do! There you will have to constantly monitor and check the condition of the belt and take preventive actions to prevent timing breaks.

Once I wrote about the PRIOR engines, they asked me - “”, read it very informatively. In this article, I promised to talk about the very principle of why this happens on some engines and not on others. In general, about the breakdown process itself, today I will try to sort everything out, especially for you “newbies”. I won’t delay, let’s go...

So valves are part G azorasp R dividing m car mechanism (timing mechanism). It should be noted that this part is quite important, without them there would be no exhaust gases released, and compression would not be created in the cylinders during fuel injection and ignition. IN modern engines there are different numbers of them from 8 to 32. But most use options with, they are the most common of all.

Principle of operation

The camshaft, which is located on top, in the cylinder head, “makes” them work by opening and closing.

It unwinds and, thanks to special ovals, presses on the valve - it opens, or releases it - it closes. In turn, the camshaft operates on a belt or chain drive from the crankshaft.

The camshaft and crankshaft are necessarily synchronized so that the opening of the valves and the movement of the piston coincide in a certain sequence - when the piston goes down, the valves open (“sink” into the chamber), when the piston rises up, they close (go up), thus creating pressure in combustion chamber, then the spark plugs ignite the mixture and the piston goes down under pressure. This cycle is repeated many times. Here is a short video clip of the work for understanding.

This is a perfectly working scheme, with proper maintenance (timely replacement) everything will travel many thousands of kilometers.

The reason why the valve bends

I would like to note that this can be either 8 or 16 valve engine. The reason is simple - it is a broken timing belt or chain. In fairness, it is worth noting that the “chain” very rarely breaks, mostly it stretches and the “hook” sprockets begin to jump, which may also be the reason.

When a break occurs, the camshaft stops abruptly, but the crankshaft continues to push the pistons. Thus, the valves go down and “sink” into the combustion chamber, the piston also goes up - which should not happen during normal operation. They meet in " top point"and the piston, having high energy, simply bends or breaks the valves. As you can see, everything is quite banal.

Such a breakdown is very expensive - you need to “half” the motor and pull out the bent elements, sometimes even the block head itself suffers (but rarely), so it will also need to be replaced. You can also encounter damage to the pistons (the valve pierces it), but here everything is even more serious, you will need to remove the camshaft and pistons with “connecting rods”.

Why does a belt break and how to protect yourself from it?

1) The most common reason is a simple failure to comply with the instructions for replacing the belt from the manufacturer. As a rule, if your car is under warranty, then the replacement will be under warranty, but if you service it yourself, then many people forget or save on replacement. It “comes out” sideways.

2) Poor quality belt, now there are just a lot of fakes, especially for our VAZs. In reality they don’t go even 5000 kilometers (it happened several times). company car), so take better proven options. Or exchange it at a service station with a guarantee.

3) The pump fails. In some car models, it is also engaged in the belt and if it fails, it simply jams and will wear out the belt in a matter of hours.

4) The camshaft itself wears out. It is made of metal and it is clear that after some time it will wear out (it may jam), although a lot of time should pass (high mileage).

5) The tension rollers of the timing system fail. They can fall off, they can jam - in any case, the belt will either break, or it will fly off - one end will bend the valves.

There is only one defense here guys. Change the belt on time, as well as the tension rollers and other elements of this system that are assigned to you according to the regulations. Buy “consumables” from official or trusted stores, because fakes sell much less than originals, here you risk every thousand kilometers, in general, a belt is not a spare part that is worth saving on.

Are there options that don't bend?

Of course there are, but now they are very rare. Once again I advise you - there are models of engines that were not bent before. However, unfortunately, there are practically no such people now. That’s why many people carry out such tuning of power units.

The point here is also banal, simple - instead of ordinary pistons they install . Then, even if a break occurs, the valves will simply fall into these holes and nothing bad will happen. It will be necessary to install a new belt and synchronize the camshaft and crankshaft.

“Great,” you say. BUT why then aren’t such pistons installed on all models? After all, this is 100% protection.

Again, everything is simple - such pistons eat up part of the engine’s power, and quite a lot. There is still debate about “how much”. Some say about 5 - 7%, but excuse me, this is DEcent! The thing is that such a piston is heavier, and the compression is not as effective. That is why many abandoned this decision. Many - but not all!

Often phrases flash in the conversations of car enthusiasts: “I got in for repairs, the belt broke, the valves were bent.” Of course, in such cases we are talking about the timing belt. In order to understand the causes of the “catastrophe”, let us consider general outline interaction of the connecting rod-piston group and the gas distribution mechanism.

This interaction is strictly coordinated, otherwise normal operation of the engine cannot be ensured.

Operating principle of the valve-piston system

Let's take the compression stroke as an example. When the piston, compressing the combustible mixture, approaches the top dead center, it comes almost close to the combustion chamber (on diesel engines - to the surface of the head). If at this moment any of the valves are not closed, then loss of compression will be the lesser evil. Most likely, the valve, the rod of which is rigidly held by the rocker arm (or camshaft cam) from above, will take the impact of the piston.

The valve bends in the event of a collision between the valve and the piston

In very rare cases, the manufacturer provides recesses in the piston crown to avoid collision. From what has been said, I hope it is clear why the valve bends when the timing belt breaks: the camshaft stops rotating, some of the valves remain in the open position, being a “convenient target” for pistons moving by inertia.

The coherence of the timing with the crank mechanism is ensured by the precise installation of gears or sprockets. To do this, installation marks are made on them and on certain points of the engine.

According to the type of torque transmission, the gas distribution mechanism drive can be:

• Belt
• Chained
• Geared

Let's look at their common malfunctions, which can lead to bending of the valves.

Timing drive device

Consequences of a broken timing belt

Some inquisitive motorists are interested in the question: is it possible to bend the valves with a starter? The answer is easy! Just do not install the sprockets or gears according to the markings - and the key is to start! If the engine starts, you will immediately learn to recognize the symptoms bent valves. Although, if you don’t “miss” too much, then everything can be corrected by assembling the timing drive according to the rules.
If just one valve is bent, the engine will run rough. Even if it is a V-shaped “six”, you will hear it.
If, after restoring the camshaft drive, the engine runs smoothly and develops the same power, then you are lucky and the manufacturer prudently supplied pistons with sufficient recesses in the bottoms. But, unfortunately, this is not always possible. First of all, when designing a motor, the designer strives to combine many seemingly contradictory qualities of his “brainchild”. For example, such as efficiency and power. This may to some extent justify the fact that at 16 valve motors Often the valve bends when the timing belt breaks.

Such problems are especially acute for the creators of diesel engines, in which compression and the necessary swirl fuel mixture set power characteristics. Therefore, the combustion chamber is located at the bottom of the piston and often has a whimsical shape.

On diesel engines valves bend more often than on gasoline ones

However, behind this lies the precise calculation and modeling of vortex flows on a computer. Such chambers are called undivided and making recesses for the valves is impractical from the point of view of high-quality atomization and maximum efficient combustion of the fuel mixture. The piston is almost close to the head of the block. Therefore, it is not yet known for certain whether there are diesel engines on which “the valves do not bend.” Although, perhaps, human genius dealt with this disaster.

Repair

Bent car engine valves

Never try to repair bent valves in any way!
Replacement, and only replacement!

If you straighten the valve “by eye,” you risk getting yourself into even more trouble. A valve restored by hand is unlikely to be aligned with the guide bushing and will press tightly against the seat. And if you want to “just a little” straighten the rod, it will work like a pump, pumping oil into the combustion chamber - no cap will hold it.
It would be prudent to troubleshoot other parts as thoroughly as possible. After all, an impact can damage guide bushings and valve seats. There are known cases when connecting rods were bent. Breakage of rocker arms is also not uncommon.

Models VAZ engines, the valves of which are not “afraid” of timing belt breakage:

VAZ 2111 1.5l; VAZ 21083 1.5l; VAZ 11183 1.6l (8 valve); VAZ 2114 1.5l and 1.6l (both 8 valve)

It is known that old 8-valve “Opel” engines (such as those on DAEWOO Nexia And Chevrolet Lanos), also calmly endure this trouble.

As a rule, if a person has bent at least one valve on his favorite car, even just once, such a person already begins to understand that even “hardware” does not have iron patience and will try to become a good owner of his “horse”.

In conclusion, it would be useful to add - keep an eye on your car, do not doubt whether there is a reason to “look under the hood”.