Audi A4

Since 1994 of release

Repair and car operation



Audi А4
+ Running gear
+ Regular servicing
+ Engines
+ Turbo-supercharging
+ Exhaust system
+ Cooling system
+ Fuel tank and the fuel pump
+ The air filter and channels всасывания
+ Injection system
+ Coupling
+ Transmission and the main transfer
+ Suspension bracket of wheels and steering
- Brakes
   Independent work on brake system
   So the brake system works
   Check of brakes
   Brake liquid
   Check of level of a brake liquid
   Check of brake system on tightness and presence of damages
   Replacement of a brake liquid
   Disk brakes
   Measurement of a thickness of overlays of forward disk brakes
   Check of a condition of brake disks
   Replacement of overlays of disk brakes
   Back disk brakes
   Measurement of overlays of back disk brakes
   Manual brake
   Check of idling of the lever of a manual brake
   The main brake cylinder
   The brake amplifier
   Check of the brake amplifier
   Works on hydraulics of brake system
   Prorolling of brake system
   The help at malfunctions
   ABS and EDS
   What does ABS?
   Function of separate knots
   Electronic system of distribution of brake effort (EBV)
   Infringements in system ABS work
   Electronic blocking of differential (EDS)
+ Wheels and tyres
+ The electrotechnical equipment
+ Ignition system
+ Illumination
+ The alarm equipment
+ Tools and devices
+ Heating and ventilation
+ Body details
+ Salon
Search of malfunctions
Technical characteristics










Replacement of overlays of disk brakes

Always it is necessary to change simultaneously both overlays at the left and on the right. Use overlays only with Ava (the General permission to operation). If the manufacturer of a brake is Lucas at replacement of overlays two are used new самоконтрящихся a bolt. They are in a set of brake overlays more often – check up. If the manufacturer of a brake is ATE bolts are not necessary.

As in process of deterioration of overlays pistons all leave in brake supports at installation of new, thick overlays they need to be wrung out back further. Thus the brake liquid is wrung out through pipelines in a broad tank. If in this time interval the brake liquid surplus needs to be sucked away now was in vain added. Otherwise the brake liquid acting from a broad tank, will corrode the nearby varnished details in an impellent compartment. For отсасывания use absolutely pure pipette or an old syringe for injections – never suck away a liquid a mouth!

Overlay replacement in brakes АТЕ

Brake АТЕ: dismantle of the overlays, the first stage: wring out a screw-driver (2) fixing spring (1).

Brake АТЕ: dismantle of the overlays, the second stage: ослабьте bolts with internal шестигранниками in protective covers (1 and 2) after removal of caps.

The third stage: the external overlay (3) in the case of brake support АТЕ (2) is pasted, the internal overlay (1) is inserted with metal скобами (arrow) into an internal aperture of the brake piston.


The piston in a brake support is wrung out by a clamp. For protection we have laid between them a small plate. Brake support Lucas established here usually remains fixed above.


 PERFORMANCE ORDER

  1. Lift and fix a forward part of the car.
  2. Remove a wheel.
  3. Turn a wheel that overlays were well accessible.
  4. Remove a screw-driver fixing springs from an outer side on a brake support.
  5. Remove caps on an inside of brakes.
  6. Establish a key with internal шестигранником in already visible internal шестигранник directing fingers and ослабьте both fingers.
  7. Take out fingers, remove the case of a brake support.
  8. Suspend the case of a brake support on a wire on an amortisation rack.
  9. Take out overlays on the right and at the left from the case of a brake support: an internal overlay should be taken out with fixing скобами from the brake piston, the external overlay should be unstuck from a brake support, – if it is necessary, with force.
  10. Wring out pistons in a brake support by means of a clamp. That the piston has not warped or was not damaged, on an adjoining ring put a small plate.
  11. Carefully remove the rests of a gluing film on an adjoining surface of an external overlay.
  12. Clean a brake support, the rust should not be, first of all, on directing.
  13. Insert new overlays to paste an external support, remove a protective film from a gluing site.
  14. Establish a brake support.
  15. Tighten directing fingers on 25 Nanometers and again put on caps.
  16. After assemblage necessarily some times press a brake pedal so that overlays have lain down to brake disks. Otherwise there will be no brake effect!
  17. With new overlays – if it is possible – brake cautiously first 500 km.

Replacement of overlays in brakes Lucas

Brake Lucas: unscrew only the bottom fixing bolt (2) cases of a brake support. Directing finger wring out in an opposite side. The top fastening (1) remains untouched.


Brake Lucas: the case of a support (2) after easing of the bottom fastening leans back upwards. Overlays (3 and 4) in the directing. Further it is visible: 1 – a heat-shielding guard in the brake piston.


 PERFORMANCE ORDER

  1. Lift and fix a forward part of the car.
  2. Remove a wheel.
  3. Turn a wheel that overlays were well accessible.
  4. Unscrew only the bottom fixing bolt of the case of a brake support, thus wring out directing finger for шестигранник in an opposite direction.
  5. Cast away upwards the case of a brake support.
  6. Take out overlays on the right and at the left from the directing.
  7. Wring out a clamp the piston in a brake support. That the piston has not warped or was not damaged, on an adjoining ring put a small plate.
  8. Track correct position of the heat-shielding screen in the brake piston.
  9. Insert new overlays.
  10. Mount a brake support.
  11. Tighten a new (!) bottom fixing bolt on 30 Nanometers. The top fixing bolt do not tighten, otherwise will disappear самоконтрящийся effect. Use narrow рожковый a key for отжима in an opposite direction of a directing finger, differently it will be jammed also by the inhaling moment will be deformed.
  12. After assemblage necessarily some times press a brake pedal so that overlays have lain down to brake disks. Otherwise there will be no brake effect!
  13. With new overlays – if it is possible – brake cautiously first 500 km.

Dismantle of a forward brake support

Forward brake supports are attached to an amortisation rack by so-called ridge bolts. These bolts for шестигранной a head have the corrugated surface which is not supposing inadvertent easing of a bolt. In no event it is impossible to replace these bolts with usual bolts!

Here the support of a brake support (3) is visible at the dismantled case of a brake support. Figures "1" and 2 designate fixing bolts of a brake support (corrugated bolts).


 PERFORMANCE ORDER

  1. Unscrew a wheel.
  2. Dismantle brake overlays with brake supports (how it is described in the previous sections).
  3. The case of a brake support with the screwed brake hose suspend so that the hose has not been tense.
  4. Or unscrew a brake hose, or a tube. In this case wring out a pedal of a brake and hold it that the brake liquid has not flowed out.
  5. Unscrew fixing bolts of a brake support on a brake support.
  6. Before installation clean corrugated surfaces of ridge bolts.
  7. Tighten ridge bolts on 125 Nanometers.
  8. Again screw a brake hose or a brake tube.
  9. Pump over brake system in the event that the brake hose or a brake tube unscrewed.
  10. Before the first metres of movement some times wring out a brake pedal to adjust a normal backlash of a pedal.

Replacement of cuffs of the brake piston

If the cuff of the brake piston in a support it is necessary to take care as soon as possible of replacement is damaged, differently soon the piston will jam because of a dirt and corrosion. Cuffs are on sale only in gathering with прокладочным a ring of the brake piston. For installation of both details it is necessary to squeeze out the piston from a brake support. For the sake of safety this work needs to be spent in a workshop. Depending on circumstances dismantle also a brake support and carry it in repair.

Replacement of a forward brake disk

Brake disks need to be changed at once from both parties. Unilateral replacement can lead not-identical to effect of braking.

 PERFORMANCE ORDER

  1. Completely dismantle a brake support how it is described, and fix a wire on a body. The hydraulic hose remains connected.
  2. The brake disk can be removed from a wheel nave only manually.
  3. If it приржавел help itself strong blows of a hammer but only in the event that the disk will vary.
  4. Before installation of a new brake disk clear an adjoining surface on a wheel nave.