What is the timing chain? Which is better: timing chain or belt?
Now there is a lot of controversy about whichthe timing control is better - the timing belt or chain. The VAZ used to be equipped with the last type of drive. However, with the release of new models, the manufacturer switched to the belt. Now many companies are switching to the use of such a transfer. Even modern units with the layout of the V8 cylinders are equipped with a belt drive. But many motorists are not happy with this decision. Why is the timing chain a thing of the past? Let's look at its features, advantages and disadvantages.
The timing chain (VAZ including) serves to transfer forces from the crankshaft to the distributor.
Thanks to it, the correctgas distribution - valves open and close in time. There are labels on the pulley. They allow you to correctly position the crankshaft relative to the distributor. Until the 90s, the chain was the main drive for ICE. Few of the automakers then imagined that in the 2000s it would be massively abandoned.
Previously, this type of drive was indeedreliable and trouble-free. It was used on gasoline and diesel engines. Often manufacturers used not one, but several rows of links. By the way, on engines ZMZ 405 and 406 apply at once two chains.
To tear such a detail, unlike a belt, is extremelycomplicated. Now there is a huge number of cars from the 80's, which without problems "ran" more than 400 thousand kilometers without changing the chain. Classical motors are really ten times safer than modern TSIs and others.
Practice shows that this transfertime is stretched. Because of this, the timing chain marks do not match. For 10 years it can stretch to 1-2 centimeters. Yes, its length is much greater. But this is quite enough for it to jump on one or several links.
On Ford vehicles, the GRM chain nurses an order of magnitude200 thousand kilometers. Further there are characteristic sounds from under the hood. But this rumble is completely curable - it is enough to purchase a repair kit with a new chain and tensioner. The problem will disappear for the next 200 thousand kilometers.
It is several times heavier than the strap. Modern manufacturers make cars lighter, more eco-friendly, and compact. In order for the car to meet the new emission standards and spend less fuel, they switch to the use of a belt drive.
As for the circuits themselves, their construction onthis moment has become much simpler. If previously used for three links, now they use only one. Also removed and the movie. Plate chains are now in place. Previously, the gears with metal sprockets included. Now this function is performed by plastic spikes. But, as the responses of car owners say, the resource of such a system has decreased at times. Together, this drive has become lighter by 5 kilograms (with lightweight housing included). But is it worth it so much to sacrifice for the sake of weight?
A lot of space under the hood
You probably noticed that the younger the car, the less space under the hood.
Manufacturers equip machines with a lot ofadditional options and mechanisms. In view of this, it is rational to use the engine compartment. The belt drive does not take up as much space as the timing chain. "Nissan" and other foreign manufacturers switched to the belt precisely because of this. By the way, on cars with a transverse arrangement of the engine and at all the chain is not applied.
What's the result?
As a result, all manufacturers switched toThe use of belt transmission, which does not take up much space under the hood and does not affect the consumption and environmental friendliness of the car. But there is one "but". Such a mechanism has the property of breaking. And it is extremely difficult to determine this, because it is closed in a plastic protective cover. The chain, when stretched, begins to emit a characteristic roar, which can be heard even with the best sound insulation.
About the resource
Because of the ease of construction and applicationthe plastic circuit resource components fell to 100-150 thousand kilometers. There are also problems when replacing it. Because of the design features, it is difficult to get and replace. In the service centers for the service to install a new chain ask from 10 to 30 thousand rubles. The more cylinders in the engine, the higher the price tag. It becomes clear why 6-and 8-cylinder engines began to equip with belt transmission.
What is better - timing chain or belt?
To begin with, we note the positive side of the chain drive:
- High resource (concerns old engines, where two and three rows of links are used).
- High resistance to external factors. The GRM chain rotates in an enclosed space. It is not afraid of water, moisture, dust and temperature changes. For a belt drive, these factors can be critical.
- Accuracy of adjustment. Unlike a belt, on a chain it is possible to expose more precisely timing marks. Due to this, the camshaft rotates with the required force. Precise adjustment is the more rational control of intake and exhaust valves. Accordingly, they do not burn out and are not crooked, even with the extension of the links.
- Grease. The timing chain is constantly in oil. The belt works "on dry". This greatly reduces its resource.
- Resistance to loads. The chain perfectly withstands high revs. With a workable tensioner, it will not jump to the tooth ahead, no matter what mode of operation.
It would seem that this is the most technologically advanced transmission in the State Russian Museum. But it is worth considering the shortcomings.
The first factor is a resource. It concerns only modern engines. For example, on cars "Volkswagen" with the motor 1,2 chain nurses no more than 50 thousand kilometers. This is less than a belt drive. The latter serves about 80 thousand. Plus, everything is expensive repairs. You can replace the belt yourself.
But to remove the chain in the absence of experience will beextremely difficult. The next drawback is noise. Such aggregates are much more orderly, even when the chain is not stretched. The belt is made of rubber-fabric materials. It is more gently attached to the pulley and works silently. Now about the hydraulic tensioners that are used in the chain drive. These parts are very demanding on the quality and oil level. If your engine eats up a lubricant, it is more often to check the probe, otherwise the liquid will not go into the tensioner and the chain will jump to the tooth. The more quality the oil, the longer it will last.
Have honest producers remained?
Speaking of modern engines with a chaindrive, it is worth noting that not all manufacturers switched to "lightweight" options. Plastic chains do not install on the engines of the popular Hyundai Solaris and its fellow Kia Rio. Even on the last generations.
Here we use a roller chain with two-row links. Its resource ranges from 150 to 200 thousand kilometers. With a timely replacement of oil, the chain also lasts longer.
So, we have found out the features of both types of drive. To answer the question "what is better - timing chain or belt" is quite difficult. We need to build on the design. If this is a classic two- or three-row chain with real, metallic (rather than plastic) asterisks, this engine is definitely worth attention. When buying a car with a timing belt, remember that it can tear and in the engine bends the valves (the latter does not apply to the engine with SOHC layout). This is fraught with expensive repairs.