VAZ 2108 - Gearbox: device mechanism and its repair

The article describes how to repair the gearbox in the car VAZ 2108. All items, details and nuances.

VAZ 2108 - CAT: device components, repair and improvement

The domestic car is a car with front-wheel drive, and the engine is placed transversely, it is used to move along the tracks. The body is made of metal in accordance with the type of hatchback, which has 3 doors. The back door is designed for loading and unloading luggage. During the transportation of long and oversized luggage, the rear row is folded - this moment increases the luggage compartment.

4-cylinder carburetor engines with a volume of 1.1, 1.3 or 1.5 liters. At the moment, some machines are installing fuel injection systems. Front-wheel drive guarantees improved handling of the car when cornering, even during a wet road. During the long use of the car, many parts wear out, the fasteners of the unit assemblies are loosened and the adjustable values are violated.

CAT is the most reliable element in the car. The breakdown of this mechanism happens quite rarely, in comparison with other parts. And with all, full or partial failure of its makes it completely unsuitable for further use of the car. It is simply impossible to exploit the car for its intended purpose. In addition, and to deliver the machine to repair the gearbox will need a tow truck.

Prevailing types of breakdowns

One of the types of breakage of the checkpoint on the VAZ 2108 It is considered the wear of the bearings or the lack of oil in the gear unit. And with all this damage is very simple to fix, by changing the oil or changing the bearings. Completely different, if it is a question of more serious breakdowns related to axial rearrangement of shafts, curvature of the handle of the gearbox, seizure, uncaused switching, disconnection of gears, wear of fasteners, various nuts, and springs by impairing the flexibility of balls - in such situations without full repair Do without.

Construction of the structure and further repair of the gearbox

Repair of the VAZ 2108 gearbox is a very difficult and time-consuming process, moreover, if the car has sufficient mileage. Despite the multiple SRTs, not all specialists can repair it. The reasons for this can be very many. For example, little experience, as well as lack of spare parts in stock. CAT - is considered a complex element of the car. It is able to change the tractive power of the driving wheels of the car due to the engagement of gears with different number of teeth.

In addition, it provides reverse and long-term disengagement of the motor (together with the clutch) with other transmission elements, while the car is either progressing by inertia. Engagement of gears with different number of teeth is realized by their movement. The drive shaft is connected to the driven clutch disk, while the driven shaft with other transmission elements.

The driven shaft in relation to the main shaft is able to rotate with a different number of revolutions. The transition shaft with a fixed set of gears through them is in constant engagement with the main shaft.

Dismantling gearbox

In some cases, this happens - the box breaks down, and the apparent cause is not immediately set. In order to identify it, the checkpoint should be dismantled. Not everyone and not always can immediately get to the SRT, and the removal of the box has to be done by yourself. For safety, its disassembly should be done together, as some parts with a significant mass in case of a fall can injure a person.

First, remove the "+" terminal from the battery and drain the liquid from the box. After this procedure, remove the pallet protection. On the crankcase there is a wire called the "mass" attached with a bolt. This wire should be removed and slightly pushed aside so that it does not tear, with the subsequent disassembly of VAZ 2108 gearbox. First take out the clutch cable. After separating the shoe from the starter relay. Remove the 3 bolts and disconnect the starter. Then we pass under the car. It is necessary to loosen the clamp and unhook the hinge from the thrust of the gear selector. Unscrew the speedometer drive cable and the rear speed lamp start-up wires.

After that, it is necessary to unscrew the nuts placed on the suspension arm. Unscrew the whole nut that connects the bracket and the extension. Next - turn the stretch to the sides, so as not to interfere with the continuation of disassembly. The cotter pin of the nut itself, which is responsible for securing the ball joint hinge to the turn handle, must be unscrewed and pulled out. The tie rod nuts should also be unscrewed.

Next - knock out the ball ball from the rack of the turn knob. Then unscrew the 2 bolts and detach the ball with the fist of the turn. With the first of the wheels of the driving wheels, the shank must be knocked out. Here you need to mount. One syllable was released, and the second should be released.

Then remove the crankcase cover. The tightening, located between it and the cylinder block, which is fastened on 3 bolts, should be weakened. Therefore, after they removed the checkpoint VAZ 2108 5 stup. The motor will remain without the bottom support, and then it is necessary to fix it. You need to do it like this:

• Take a powerful wooden beam, the length of which is about 1.5 m.
• Fasten the supports of the front pillars so that it is placed above the motor.
• Fasten the motor to the bar, using a chain or strong ropes.

After the motor is fixed, you can safely detach the rear, as well as the left support from the frame of the machine. Then, move the box in the opposite direction from the motor until the primary shaft is free of clutch. You should be careful not to break the petals, placed on the spring of the diaphragm of the clutch.

In principle, the entire procedure is completed, now the gearbox from the engine VAZ 2108 can be disassembled further for the replacement of worn out items.

Improving the gearbox by selecting gear ratios

Many techniques used in the transmission tuning have been tested in automotive sport. For any machine, the more sporting, the gearbox is an important element in implementing the dynamic qualities of the engine. Correctly selected transmission gear ratios VAZ 2108 Make a fast car with a fairly weak power unit.

Auto, which relate to serious training, use cam gears. They are determined by many advantages - they can withstand sufficiently large loads (using the shape of the tooth and the way the gear-cam clutch is engaged). They need less time to switch speeds (due to incomplete bonding or, in general, not squeezing), the more they do not destroy the synchronizers (which simply do not exist).

But still, the cam gears are practically unsuitable for normal trail travel, since they produce a lot of noise (thanks to the use of spur gear pairs), they have a "hard gear shift" and have a rather small resource. In addition, they are much more expensive than synchronized ones, and should be constantly professionally serviced.

From conventional gearboxes, synchronized differ only in gear ratios. Individual situations (VAZ of the eighth model) allow expansion to the sixth gear. Good work of the checkpoint is carried out by an effective selection of the gear ratios of the main pair of the reduction gear, the primary shaft and the driven gear of the secondary shaft. The choice of gear ratios is due to the power, as well as the instantaneous capabilities of the motor, the diameter of the wheels, and most importantly from the wishes of the motorist.

Below the gear ratio Gearbox VAZ 2108 Mean the ratio of the number of teeth on the driven gear to the number of teeth on the drive gear. If it is increased, the transmission will become "more powerful", also "shorter", in another way, the engine will wind the required number of revolutions. The speed of auto is also typed quickly, you only need to switch gears frequently. This moment will only be reflected in a certain decrease in the maximum speed of the transmission used.

On an example - we take driving on VAZ of the eighth model with the motor of 1.3 l. With the main pair 4.5. It feels as if something very powerful was placed in the engine room, not exactly VAZ. Although the driver needs to frequently switch the handle of the VAZ 2108 gearbox, but with every action, even at a traffic light, the car is the first. In sports cars gears are used the most "extreme" - 4.7, and on cross - very 5.1.

How to replace the gearbox with a VAZ 2108

Not all cases are reasonable repair of the gearbox VAZ 2108, the exchange in most situations is more reasonable and simpler. Buy PPC can be new or used in the past. The choice of the site is determined by the advantages, money possibilities of the motorist. Used box is advantageous to buy on parsing. In sales there are serviceable spare parts with development of opportunities less, than half. The advantages of the used units are obvious.

The checkpoint is parsed with a factory without a factory fault (passed the test by the route), it was diagnosed by the service center professionals before the sale, it is serviceable and efficient, and at all its cost is less compared to the new one. Actually for the checkpoint VAZ 2108 the cost is determined by the nodal type (4 or 5-band), the level of wear. By installing this checkpoint, you can save money, as well as time to repair.

It is possible to make a replacement for the gearbox VAZ 2108 With 4-step on 5-step. Then the car's capabilities will become several times larger, it will also depend on the type of engine. After all, it happens that with a 4-band transmission, the car seems to lack another speed.

In the event of a breakdown of the output shaft of the gearbox, it is necessary to correct it

• It is necessary to clamp the secondary shaft of the gearbox VAZ 2108 in the vice with metal soft lining on the lips.
• By means of 2 mountings, the ball bearing behind the secondary shaft must be pressed.
• Remove the thrust washer.
• Remove the driven gear of 4th speed.
• After removing the needle bearing of the driven gear of 4th speed, and be sure to mark.
• Then remove the spacer from the secondary shaft.
• By means of 2 mountings through the gear of the third speed, move the synchronizer of the 3rd and 4th speed from the splines of the secondary shaft.
• Remove the needle bearing bush of 4th speed.
• Then remove the synchronizer of the 3rd and 4th speeds with the lock washer of the 4th speed. Mark the synchronizer locking washer with respect to the synchronizer coupling.
• Then remove the lock from the secondary shaft. Washer of synchronizer of gear of 3rd speed, after marking with regard to synchronizer clutch.
• Remove the 3rd speed gear from the secondary shaft.
• Remove the needle bearing of the 3rd gear from the secondary shaft, then mark the needle bearing.
• Remove the thrust washer of the abutting rings.
• Remove from the secondary shaft 2 stop half rings.
• Remove the ball that secures from the hole on the secondary shaft.
• Remove the 2nd speed gear from the secondary shaft.
• Remove the needle bearing of the gear of the 2nd gear, then mark it.
• Remove the lock washer from the secondary shaft (spring washer).
• Position the secondary shaft of the 1st gear gear on the lips of the vice, then hit the end of the secondary shaft with a wooden kyanite, compress the 1st and 2nd speed synchronizer from the splines of the secondary shaft.
• Remove the synchronizer 1 and 2 speed from the secondary shaft with the lock. Washer of the 2nd speed synchronizer.
• Next, remove the ring from the secondary shaft that blocks the 1st speed, after marking the synchronizer locking washer with respect to the synchronizer clutch.
• Remove the gear of the first speed.
• Remove the locking ring.
• Slightly release the lock of the needle bearing of the 1st speed and remove it, pushing the latter along the length of the secondary shaft. After marking the needle bearing.
• Turn the secondary shaft by means of 2 large screwdrivers to press the inner washer of the bearing in front of the secondary shaft. After removing the washer.
• Clean, rinse and dry the secondary shaft elements well. It's good to inspect them.
• Check the condition of the shafts. If the bearings are worn, they must be replaced. Slots of shafts must be without dents and all kinds of defects.
• To check up position of a gear wheel of check point VAZ 2108. In case of chips of teeths, any other damages, gears need to be changed.
• Check the bearings in which situation, and in case of damage, change them.
• The radial clearance of the existing ball bearings must not be more than 0.05 millimeters. Check this indicator with the indicator.
• Next, check the position of the lock. Rings synchronizer. If there are nicks and all kinds of chips, you should change them.
• Next, check the clearance between the gears and the locking rings. The smallest clearance should be 0.6 millimeters. In the case of a smaller gap, the lock. The ring should be changed.
• If there are taunts and dents on the thrust washers, as well as locking rings, you must change them.
• Collect the secondary shaft in the same way as it was removed. Locking rings must be placed with marks marked first. The newest rings put in such a way that they are combined with the grooves of the hub.
• The ball bearing on the rear of the secondary shaft is pressed through the required mandrel, making the over-force, to the ring inside the bearing
• After you have collected, you should check the operation of the synchronizers. Moving their couplings manually to the position of enabling the proper speeds.
• In general, this way the bearings of the gearbox are removed from the car VAZ.

Existing series of checkpoints

The series of the checkpoint VAZ 2108: 1 - 3.42, 2 - 2.11, 3 - 1.35, 4 - 0.96, 5 - 0.78, 6 - 0.69

They are also called "commercial", because for many years they were considered quite famous, and also sold by the ranks. In general, this is true at the moment. The elongated first speed, the second and fourth - are shortened. Any changes are minimalized (five percent each), and this is enough to correct the shortcomings of the staffing series. In most cases, it is put with GP 4.1. Pleases that it stands within the norm. Gives improved overclocking.

KP front-drive VAZ

The first VAZs of the eighth model, descended from the assembly line in 1984 of the last century. They were equipped with 2-shaft gearboxes, which were combined in 1 case with a differential. Since then, the gearboxes have been updated in every way. But since there have been some changes in the elements, they are not completely interchangeable. In the first VAZ of the eighth model four VAZ-2108 checkpoints were installed, as well as 5-band checkpoints without a feeler gauge.

At the moment, there are practically none. In the 4-band, the main pairs 4.1, also 3.9 were put. In the five-band 3.9, also 3.7. A big choice in the concern decided not to spoil and used the main pair only one - 3.7. As for the gear ratios, they were, as they were, and are still only one for all cars.

Tips for replacing the gearbox

Many drivers for replacing the VAZ 2108 4-band transmission at the checkpoint 5-band. Thus, the speed probabilities of the car are increasing, the acceleration dynamics are being improved. Nevertheless, the 4-speed transmission is already the last century. And to modernize your car just fit 5, and in some cases, they even put a 6-speed gearbox, for which the same VAZ 2108 gearbox bearings are suitable.

A few words in conclusion on all the above

KPP VAZ eighth model realizes the reform of torque, transmitted from the motor in size and direction. This moment is necessary for maintaining the required speed, well, and patency of the car, for the greatest economy of the engine and advancement of the car in reverse. In addition, the gearbox separates the engine and transmission for stopping and parking the car, and even during the inertia with the engine running. For all this, you need a gearbox.