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What is a timing belt? Timing decoding
What is a timing belt? Timing decoding
Anonim

How the decoding of the timing sounds, for sure, many people know. Yes, this is a gas distribution mechanism. But here's what he does, and what properties he should have, not everyone will say. It is worth noting that this mechanism is the more difficult, the more valves are installed in the motor. For example, most budget cars are equipped with 8-valve engines. They are easier to operate, less power, and repairs are quite simple. Especially replacing the timing belt, since the system has only one camshaft. Fewer marks means more chance of accurate installation.

Camshaft in timing mechanism

timing decoding

So, it's worth starting from the most important node. Of course, according to the degree of importance, their separation is carried out purely conditionally, since even the smallest bolt or key plays a significant role. But still, the camshaft is the basis; without it, the gas distribution mechanism of the engine will not be able to work. With its help, the valves are shifted, they open and close in a timely manner,to let the air-fuel mixture into the combustion chamber, or to release exhaust gases from it.

Role of valves

operation of the gas distribution mechanism

They mentioned valves, but without them, the system would not be able to function either. They are installed in the cylinder head. There are pastels in the cylinder head against which the piston plates rest. It is necessary that the fit of the planes be as tight as possible. Only in this case can high engine power be ensured. The decoding of the timing indicates that the camshaft must be driven. For this purpose, a belt mechanism is used, which drives the camshaft pulley. And a special roller is used to adjust the belt tension.

What role do valves play in timing

timing gear drive

Now let's talk about the functions of the valves. In order to appreciate their work, you need to look at how the engine will function if they are not. For example, we can take two-stroke motors, which are still used on lawn mowers, chainsaws, and on some mopeds and motorcycles. Firstly, the noise level of the motor is significantly higher. This is due to the fact that the combustion chamber is not separated from the exhaust system in any way. Secondly, engine power is significantly lower, since the tightness of the combustion chamber is less.

It can also be noted that the correct operation of the gas distribution mechanism of a four-cylinder engine is the key to high power andtorque. And building a two-stroke four-cylinder engine is much more difficult, and sometimes even impossible. And is there any point if it is impossible to squeeze the maximum performance out of it? Also remember that two-stroke engines need oil to be added to the fuel. Will you constantly measure and add engine oil to the tank at the gas station? Probably not.

What happens if labels shift?

gas distribution device

And now turn on your imagination, because you have to imagine a difficult process that occurs when the labels are shifted. If the timing drive is installed and configured correctly, taking into account all marks, then the engine will work perfectly. But what happens if the belt suddenly slips a few teeth? Yes, this happens quite often, even a timing belt can slip on a pulley if it is loose.

And literally the following will happen: the movement of pistons in cylinders and valves will occur asynchronously. Timing decoding says that intake and exhaust must occur in a timely manner, depending on the position of the pistons. Therefore, the intake stroke will start earlier or later, similarly to the exhaust. The air-fuel mixture will not enter at the right time; at best, its ignition will occur in the middle position of the piston in the cylinder. In other words, sheer chaos begins in the motor. And all this is due to the fact that some belt jumped a few teeth.

How will the cliff endtiming belt?

gas distribution mechanism vaz

But if the timing belt broke, then not every engine is able to survive such an event. On most engines, this phenomenon is accompanied by deformation of the valves, which literally run towards the pistons, as if on a date. Sometimes such a romantic meeting ends with the valve breaking through the piston. The device of the gas distribution mechanism implies that it is impossible to do without a major overhaul. Well, if the cylinder block is not damaged.

The saddest ending is the appearance of cracks on the block. It will be a little easier if the crack goes along the cylinder head. Unfortunately, if the car is planned for sale, then some owners brew and grind these damages with argon. But this is not a way out, it is better to replace the cylinder head, even if it was used, but not deformed or damaged. And do not forget that the replacement of the gasket is also mandatory. In general, this element is always put in a new one, each time the cylinder head is removed.

How to install marks on an 8-valve engine?

system engine

Assume that all preparatory work has been completed. The alternator belt is removed and inspected for damage, the right side is raised and the wheel is dismantled, the crankshaft pulley bolt is unscrewed. In other words, access to the timing belt is completely open. Now the main thing is to do everything right.

First of all, remove the roller using the key at 17, but do not lose the washer, which is locatedunder him. With its help, the position relative to the belt was adjusted. Now you can remove the old belt, put a new roller. After that, simply install a new belt if the pulleys were not affected.

But if everything is done according to the "book", then you need to double-check whether the marks match, and for this you need to know in general terms the gas distribution mechanism of the VAZ. You need to focus on two marks - on the camshaft and on the flywheel. The first is installed opposite the plate, which is located on the cylinder head from the side of the windshield. You can see the second one after you remove the rubber plug from the clutch housing. There is a mark on the surface of the flywheel, it must be set clearly in the middle of the slot in the plate, which is attached to the engine block. The crankshaft is scrolled using a 19 key. Turn the bolt on the crankshaft pulley with it.

The task becomes more difficult: setting up a 16-valve engine

engine gas distribution mechanism

Too loud words, of course, but still, some motorists grab their heads when it comes to 16-valve engines. This behavior is justified by the fact that there are many shafts and marks that are very difficult to set up. Judging by the behavior of such individuals, even in a grove of three pines they are able to get lost and look for a way to the house for a long time. Nothing is impossible, especially when it comes to a car. You have already understood how the timing decoding sounds, considered its main functions and elements. There is nothing super complicated about it.

The only thing you need to install the timing belt onA 16-valve engine is to fix the relative position of the camshafts. For this purpose, you first need to set each according to its marks, after which, trying not to displace even a millimeter, fix the plate between them. It will help to get rid of accidental turning of the shafts. On the other hand, it is very difficult to rotate the camshaft - great efforts are needed to overcome the resistance of the springs. Therefore, such a measure is only advisory in nature. Much more important is to fix the crankshaft. That's all, now it remains to replace both rollers and install a new belt. After assembling the assembly, the car is ready for operation.

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