Stop any machine is due to friction. It occurs between the pads and the metal surface of the disc or drum. On VAZ cars of the Samara series, disc brakes were installed on the front axle, and drum brakes on the rear axle. The latter have a high service life due to the fact that they account for about 30% of the total load when the car stops. But still they need to be constantly checked and changed. We will tell you how to replace the rear brake pads on the VAZ-2109 in our article.
When is replacement performed
Usually replace the rear brake pads on a VAZ-2109 car in such cases:
- If the friction linings are completely worn out, while the layer thickness is less than 1.5 mm.
- If there are traces of oil on the clutch surface.
- The pads have a lot of free play, with the base theyvery loosely connected.
- There are chips, cuts and other signs of deformation on the pads.
Design and features of pads
On VAZ-2109 cars, like on most budget models, drum brakes are installed at the rear.
Their design is not very complicated, just a few components can be distinguished:
- Metal base.
- Friction lining. It is connected to the base with the help of an adhesive composition. Rivets are sometimes used.
Rear Pad Features:
- In total, two pairs of pads are placed on the rear axle.
- Metal parts coated with anti-corrosion layer.
- The friction pad is glued to the base. This is done at a temperature of 100 degrees.
- Due to additional processing, the necessary roughness is given to the surface. This speeds up the grinding of elements.
- Please note that the force acting in the system is very large. So, when braking from a speed of 80 km / h, the following indicators are relevant: the force on the pads is 320 Nm; pressure in the brake system - 40 bar. The pads may move off the surface of the base. To do this, they need to be affected by a force of 210 N/cm2.
- The materials from which the pads are made are fully ISO 9001 certified.
- Due to the use of modern means during braking, the noise level is reduced. This, of course, affects the comfort of people,in the cabin.
- The elements have very high wear resistance. Their resource under normal conditions is 70-90 thousand km. But it all depends to a greater extent on what kind of driving style the motorist has. Not the last role is played by the quality of the road surface on which the car moves.
It is imperative to timely replace the rear brake pads on the VAZ-2109. With your own hands, all the work can be done fairly quickly, but you will have to take into account some points. Most importantly, stick to the sequence.
How to remove pads?
Before replacing the brake pads on the VAZ-2109, you need to remove them. It is recommended to thoroughly clean the entire surface under them: dirt and metal chips usually accumulate there. Disassembly sequence:
- Handbrake lever needs to be pushed down.
- Shift into first gear at the gearbox.
- Install chocks under the front wheels.
- It is recommended to raise the entire rear of the machine by placing it on stands.
- Next, remove the wheel and completely clean the entire mechanism. Please note that do not use gasoline, diesel or mineral type solvents for cleaning.
- If there is a lot of liquid in the expansion tank (close to the maximum mark), then you need to pump it out a little. Otherwise, the liquid may splash out during the replacement.
- Unscrew the two pins and carefully remove the brakedrum.
- Use the pliers to remove the lower and upper springs. You also need to remove the guide spring, which is located on the front shoe (in the direction of travel).
- First remove the front shoe, then remove the expander bar and guide spring. Disconnect the drive lever from the handbrake cable.
- Remove the cotter pin and remove the support washer.
- Remove the rear pad and remove the support washer.
How to install new pads?
Before replacing the rear brake pads on the VAZ-2109, you need to make sure that this is necessary. Visually inspect the condition of the element, use a ruler to measure the thickness of the clutch. Brake pads are installed in reverse order. It is recommended to press the piston cylinders with a hand vise. It is also necessary to machine the drums and center them. If the thickness of the drum is small, then you need to put new ones.
When removing and replacing the rear brake pads on the VAZ-2109, it is not necessary to bleed the system. This will have to be done if you are replacing the cylinder or line tubes.