Replacing the timing chain on a VAZ 2107

If the owner of the VAZ 2107 at some point began to notice that the car was behaving strangely, and its strange behavior was accompanied by a characteristic buzzing coming from under the hood, then you need to be careful. There is a high probability that the timing chain on the engine has weakened and needs to be urgently tightened or replaced. An experienced driver can change the chain himself. Let's try to figure out how to do it with the least effort and nerves.

The purpose of the timing chain and its length

In order to understand the purpose of the gas distribution chain, it is necessary to describe in general terms what the engines of the classic VAZ models are. All of these engines are top notch. That is, the timing shaft (also known as timing) is located at the top of the engine, above the crankshaft and above the oil pump shaft.

Timing chain - the main link of the VAZ 2107 engine

All these axles are equipped with sprockets on which the timing chain is placed. The task of the chain is simple: it must transmit torque from the timing shaft to the crankshaft and oil pump shaft. From the crankshaft, torque is transmitted to the chassis, and from there to the drive wheels. They start turning and the car moves forward. Therefore, the timing chain is the most important link among the three shafts of the engine, and the failure of this link will inevitably lead to serious engine malfunctions or its complete blockage when the chain breaks.

Timing chain length for VAZ engines

If the driver decides to replace the timing chain on his "seven", he will go to the parts store, where he will inevitably face the question: which chain to choose?

You need to know a simple rule: all VAZ "classic" engines are equipped with chains only. The difference is only in the length of the chains, or rather in the number of links:

• chains of 114 links. They are installed on VAZ 2102, VAZ 2101 and VAZ 21011 (these short chains are designed for small engines - from 1,2 to 1,3 liters);
• chains of 116 links. They are installed on VAZ models from 2103 to 2107 inclusive. The same chains are installed on the Niva (VAZ 21213). The need for a longer chain is due to the increased displacement of the engines, which varies from 1,5 to 1,7 liters.

Based on the above, the driver in the store will have to determine which chain to buy, short or long. There are two ways to do this:

• The first way is obvious: just count the number of links. If there are 116, then a chain was found on the VAZ 2107;
• the second way is easier - the chain needs to be folded in half, and then look at a pair of end links. If these links are symmetrical, then there are 116 links in the chain. If not, then the chain is short, 114 links.

It should also be noted here that lately fake retail chains have often been found on store shelves. Fortunately, fakes are made rather carelessly, so an attentive car enthusiast will immediately suspect something was wrong.

Video: how to recognize a fake timing chain

The main elements of the timing chain tensioner system

The timing chain on the engine rests not only on the three sprockets mentioned above. It is compatible with various other mainstream devices.

The timing chain tensioning system consists of several important elements.

Let's deal with them in more detail.

Timing chain stop pin

The timing chain on the VAZ 2107 engine is supported by a complex tension system. One of the elements of this system is the restrictive finger. This is a small cylindrical part screwed into the wall of the cylinder block. The pin is located next to the crankshaft sprocket. The purpose of the pin is as follows: If the timing chain tension suddenly loosens, the pin will prevent the chain from slipping off the crankshaft sprocket.

The design of the limiting pin is extremely simple - it is an ordinary bolt with a head truncated on the sides

At the same time, the chain with a characteristic tinkling will begin to touch the limiter, which will certainly attract the attention of the driver, since this sound will be heard even in the cabin. In the event of a chain break, the limiter will prevent it from completely flying off the sprocket and breaking the nearby sprockets of the oil pump and timing shaft. Under normal tension, the timing chain does not touch the limit pin, since in this case there is a constant gap of about 1,5 cm between it and the pin.

About timing chain tensioners

The purpose of the timing chain tensioner is easy to guess by its name. The chain must be constantly tightened, not allowing it to sink. If the chain has sagged at least half a centimeter, it can fly off one of the sprockets (although this happens very rarely, there are many more situations when the chain rests on the sprocket, but at the same time jumps a few teeth forward, as a result of which the uniformity of their tension is completely disrupted , and the distortion increases even more). At different times, different types of tensioners were installed on the VAZ 2107.

Mechanical tensioners

In a mechanical tensioner, the force required to press the idler shoe against the chain is generated by a conventional spring. Press the stem, it extends from the body and presses on the shoe. And the block, in turn, puts pressure on the chain, constantly damping its vibrations.

The main element of the mechanical tensioner is a piston spring.

The spring in such a tensioner is regulated by a conventional plunger nut. If the rider needs to tighten the chain a bit, simply tighten the nut slightly to take up the slack.

Mechanical tensioners on the VAZ 2107 are reliable and simple in design

Automatic tensioners

Automatic tensioners were installed on later VAZ 2107 models. Unlike mechanical devices, this tensioner has a toothed bar with a ratchet.

The main element of the automatic timing chain tensioner is a toothed bar

The plunger spring presses on this rod, and the rod transfers this force to the shoe. The ratchet mechanism prevents the rod from returning to its original position. Thus, a constant tension of the timing chain is maintained.

Finding automatic tensioners for the VAZ 2107 for sale has recently become more and more difficult

Hydraulic tensioners

These tensioners were installed on the latest VAZ 2107 models. The main difference between these devices is the principle of their operation. The force on the hydraulic tensioner is not created by a spring, but by oil pressure. It is fed to the tensioner through a reinforced high pressure hose.

Oil is supplied to the hydraulic tensioner through a special reinforced hose

Timing chain guide

The timing chain guide is another essential element of the tensioning system, without which the timing chain cannot function smoothly. The damper is a metal plate that is attached to the wall of the cylinder block.

The timing chain guide on the "seven" is a simple metal plate held on by two bolts

This plate is located in front of the tensioner, that is, the damper acts on the second half of the chain. Since the tensioner presses very hard on the chain, the opposite side of this chain will inevitably begin to vibrate. A damper is needed to dampen this vibration. The chain, hitting the damping plate, loses some of its energy and the amplitude of its oscillations is significantly reduced. Without the restrictive action of the damper, the chain will stretch much faster.

Timing chain jump and its signs

The chain, like any other part of the car, wears out over time. Wear usually shows up as chain stretch. The cause of stretching is the so-called metal fatigue, which affects almost all parts that experience cyclic loads. When stretched, the chain begins to sag significantly. If the driver does nothing, then sooner or later a situation will arise when the chain on one of the sprockets jumps one or two teeth forward. After that, all valve timing in the engine, as well as its operation, will be violated. Here are the main signs of a timing chain jump:

• the engine runs intermittently and they occur even at idle;
• during movement, power drops appear, which most often occur when the car accelerates;
• the engine starts very poorly, and this does not depend on the outside temperature;
• a characteristic ringing sounds under the hood, which intensifies as the engine speed increases.

All these signs indicate that the timing chain has not only weakened, but also jumped. And the driver should replace it as soon as possible. If this is not done, the engine will sooner or later stall, after which an expensive overhaul will have to be carried out.

The procedure for replacing the timing chain on a VAZ 2107

Before starting the replacement, it is necessary to select all the necessary tools and consumables. We will need the following things:

• new original VAZ chain with 116 links;
• keys included;
• end heads and long neck;
• screwdriver;
• a piece of steel wire 20 cm long.

Sequence of operations

Since replacing the timing chain is a serious operation, it cannot be carried out without preliminary preparation. This preparation includes a complete drain of the coolant and removal of the radiator.

1. The valve cover is removed from the end head. Opens access to the sprockets on the crankshaft and camshaft. These sprockets have small notches, marks that must match the raised marks on the timing case.
   
   Before replacing the timing chain, it is necessary to align the marks on the shafts and the housing
2. After alignment, the car is engaged in fifth gear, and its wheels are securely blocked by a hand brake. Next, using a 38 open-end wrench, unscrew the crankshaft mounting bolt. To turn this bolt, you need to make a lot of effort. Therefore, it makes sense to screw a steel tube to the key and use it as an additional lever.
   
   To unscrew the crankshaft nut, you need a 38 wrench and a lot of effort
3. After unscrewing the crankshaft nut, access to the front cover of the engine opens. It is held on nine studs with 14 nuts, which are convenient to unscrew with a socket head with a long collar. In addition to the studs on the crankcase, there are three more mounting bolts that hold the cover in place. They must also be unlocked. The cover is removed.
   
   The motor cover is held on by nine external screws and three screws on the tray, which must not be forgotten
4. The oil pump sprocket has a lock nut. This key must be bent with a flat screwdriver and removed. After that, you can loosen the fixing nut. This is done with a 15 key. The camshaft pin is removed in the same way. Your sprocket also becomes weaker after you remove the cotter pin.
   
   To straighten the keys on the shafts, you must use a hammer and screwdriver
5. Now unscrew the chain tensioner nut. The tensioner is removed and the chain becomes very weak.
   
   The tensioner nut will have to be unscrewed, since without it it will not be possible to loosen the chain
6. A loose chain can be easily removed from the axle sprockets. It is removed and replaced with a new one.
   
   After loosening the tensioner, the timing chain sags a lot and can be removed manually

About assembling the timing and installing the chain on the marks

As mentioned above, the timing has a marking system that allows you to correctly install the drive sprockets and timing chain after replacement.

1. If the timing chain was changed on the carburetor "seven", then the oil pump sprocket, which was weakened above, is pulled up first. In this case, the mark on the sprocket is aligned with the protrusion on the body (and if the “seven” is a nozzle, then this element does not play a significant role).
2. The chain guide and tension shoe return to their place.
3. The crankshaft sprocket is now in place. It also has a recess mark, which should also be aligned with the protrusion on the timing case, and only then tighten the lock nut on the sprocket and install the cotter pin in its place.
4. After adjusting the crankshaft sprocket, a new timing chain is put on according to the marking.
5. Now it remains to install the camshaft sprocket in its place. The asterisk is not stretched. Put a timing chain on it. In this case, the sprocket must be rotated so that the risk on it coincides with the risk on the cylinder block. If it does not match, remove the chain from the teeth and turn the sprocket in the correct direction until the marks match completely.
   
   Before tightening the sprocket on the camshaft, carefully align the marks
6. If the risks coincide, it is necessary to check the coincidence of the marks on the remaining asterisks. If there is no discrepancy between the marks, you can tighten the camshaft sprocket and install a key to it.
7. Now it remains to replace the timing cover, and then put it on the previously removed radiator.

Video: how to install the timing chain on the marks on the "classic"

About replacing a single-row chain with a double-row one

On the first VAZ 2107 models, mainly double-row timing chains were installed. This technical solution had its advantages:

• the distribution of mechanical load along the length of the chain was more uniform, which significantly extended its service life. Double-row timing chains cover 100-120 thousand km, while there are no signs of stretching on such chains;
• double stranded chains are more secure. If for any reason a link in such a chain fails, the chain will not be completely broken. This gives the driver the opportunity to stop the car in time, having heard the characteristic sound of a half-broken chain coming from under the hood. A timely stop, in turn, prevents engine jamming and costly repairs.

The main disadvantage of a two-row chain was its heavy weight. That is why in later models of the VAZ 2107 they decided to abandon it. However, drivers concerned about engine safety and reliability can always return a two-turn chain. To do this, you will need to replace not only the chain itself, but also the entire tensioning mechanism, from sprockets to the shock absorber and tensioner shoe. Shoes, as you might guess, should be wider, that is, with the expectation of two rows of bindings. Shaft sprockets must also be double row.

To install a double-row chain on the "seven", you will need to install special double-row sprockets

Previously, all these parts could be purchased in one set. Now these kits are becoming rarer and rarer, so drivers have to buy everything separately. The company's products "Kedr" is in great demand. This manufacturer produces not only chains, but also double-row sprockets.

The chains of the company "Kedr" are in great demand among the owners of "sevens"

The sequence for installing a double-row chain on a VAZ 2107 is no different from the previous one. There is only one feature: instead of single-row stars, double-row ones are installed. The same is true for the tension shoe. The procedure for installing a double-row chain using markings is no different from that described above.

Thus, the timing chain is the most important part of the engine. The consequences of failure of this part can be catastrophic. In especially severe cases, a jammed motor cannot be restored at all. It is for this reason that the motorist must carefully monitor the condition of the circuit and change it at the slightest suspicion of a malfunction. Replace the chain according to the forces and the novice car owner. Despite the apparent complexity of this procedure, there is nothing wrong with it. The main thing is to correctly install the chain according to the marking, and there will be no problems with its further operation.