Audi 80/Avant (B4)

Since 1991-1995 of release

Repair and car operation

Audi 80/Avant
- The description
   The chassis
   15-inch wheels
   Brake system
   Passive safety
   Full drive
   Distributive Torsen-differential
   Dynamics of movement at a dry road covering
   Instructions on operation for all-wheel drive cars
   Blocking of differential of the back bridge
   Motor compartment
   Regular servicing
   The workplace organisation
   Lubricant works
   The oil expense
   Correct choice of engine oil
   Replacement of engine oil and the oil filter
   Check of level of a working liquid of the amplifier of a wheel
   Check of level of oil of a mechanical transmission
   Check of level of oil in a drive of the back bridge
   The control of level ATF in an automatic transmission
   Check of level of oil in the main transfer of an automatic transmission
   Replacement ATF
   Greasing тросовых drives, hinges and locks
+ Engines
+ System of release of the fulfilled gases
+ Cooling system
+ Fuel tank and the fuel pump
+ The air filter and воздухозаборные channels
+ Injection system
+ Coupling
+ Transmission and transmission
+ Suspension bracket and steering
+ Brake system
+ Antiblocking system of brakes
+ Wheels and tyres
+ Kuzovnaja electrosystem
+ Ignition system
+ Illumination
+ Signalling devices
+ Devices and auxiliary devices
+ Heating and ventilation
+ Body elements
+ Search of malfunctions
+ Specifications


Full drive

On an illustration the distributive Torsen-differential in a cut is presented.

1 – a leading gear wheel (a drive to the forward bridge);
2 – a hollow shaft (a drive from the transfer mechanism);
3 – the differential case;
4 – a flange/kardannyj a shaft (for a drive of the back bridge);
5 – a worm of the main transfer of the back bridge;

6 – cylindrical gear wheels;
7 – an axis of worm wheels;
8 – worm wheels;
9 – a worm of the main transfer of the forward bridge.

If will establish authorship of any firm in a question on introduction of a full drive for serial cars in a decent society it, undoubtedly, will give Audi.

The identikit of car Audi 80 quattro demonstrates transmission to the back bridge with карданным shaft, the main transfer of the back bridge and leading semiaxes of the back bridge.

The off-road car VW Iltis, developed by request of the Bundeswehr firm Audi for Volkswagen, most likely, has served as a germinal cage for idea quattro (a full drive). The legend says:

During a winter trip to Northern Sweden one modest Iltis has far overtaken much more powerful and fast front-wheel Audi. After that the head of tests of a running gear of that time has wished to have the all-wheel drive car with sufficient capacity as the daily car. And as it is known that there is nothing more strongly the idea which time has come (and this idea, appear, was such), over the concept worked until has been presented legendary Audi quattro.

Concepts of a full drive

Connected full drive

Until recently the concept of "the all-wheel drive car was almost inseparably linked with concept of "the off-road car. The concept of a full drive of the last was simple enough: to a standard drive (the engine ahead, the drive back) has been simply attached one more drive, namely to the forward bridge one more transmission through a distributing box and additional карданный conducted a shaft.

Trips were carried out usually with a standard drive and only in the event that it was demanded by position on road, the forward drive was connected. This design with a connected full drive and is today usual for cars of the raised passableness (off-road cars).

Lack of similar system: at trips on a firm covering the full drive should be disconnected, because on turns forward wheels pass longer way, than back. Various frequency of rotation of wheels lead to difficulties with management.

Constant full drive

So, if the idea has come to a head to create the constant full drive constantly operating on all four wheels it is necessary to create the device preventing проскальзывание of wheels. This problem is solved by so-called interaxal differential.

Differentials in motor industry are known for a long time. They distribute a twisting moment between right and left driving wheels.

There too it is necessary to counterbalance forces because, as it is known, the external wheel takes place on turns longer piece of a way, than internal. The balance weight role incurs axial differential. He allows to transfer the moment on both drivers wheels depending on angular speed of each of them.

The Torsen-differential design is based on a worm gear principle. The worm gear can be calculated in such a manner that it will possess the big or smaller factor of blocking.

1 – a worm, 2 – a worm wheel.

In the winter, for example, happens so: the wheel standing on ice is turned, and the opposite wheel on a rough covering does not transfer any force and consequently costs. Clearly one: the similar differential is not necessary for a role interaxal because it is necessary to achieve opposite effect. Force should be transferred there where wheels can move the car. Namely there, where the road covering possesses good coupling. And as the driver never it foreknows, distribution should occur automatically.

After various development cycles, including interaxal differential blocked manually, all-wheel drive models Audi quattro today are completed by so-called Torsen-differentsialom.