Granta 4 new size
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about checking the chassis and transmission
check the steering
According to the maintenance regulations, we check the condition of the brake system every 15 thousand km.
We carry out the work on an inspection ditch or overpass.
To check the functionality of the vacuum brake booster when the engine is not running, press the brake pedal 5-6 times and, holding it down, start the engine. If the vacuum booster is working properly, after starting the engine the pedal should move slightly forward. If this does not happen or the braking is not effective enough (you have to press the brake pedal with great force), you need to check the tightness of the connections of the vacuum supply hose to the vacuum booster and the serviceability of the booster itself.
We check the condition of the brake pipes. The tubes must be securely fastened in the holders and have no dents, mechanical damage, deep corrosion, or signs of brake fluid leakage. If necessary, we tighten the connecting fittings or replace faulty parts.
We inspect the brake hoses; there should be no cracks, tears or abrasions on them.
We check the condition of each hose by creating fluid pressure in the brake system. To do this, the assistant must press the brake pedal firmly and hold it during the inspection. The appearance of rubber swelling or brake fluid leakage from the hose and its tips is not allowed. If damage is detected, replace the hoses as a set.
We check the condition and degree of wear of the brake pads and discs of the front wheels. To check, remove the front wheels one by one.
Removing fastening elements
So, let's start replacing the brake discs. First you need to loosen the wheel bolts. Then you need to lift the car using a jack. When the wheel nuts are safely unscrewed, you should remove the wheel itself and place it under the front suspension. This is necessary for safety reasons, otherwise you never know what could happen during the work. It is recommended to place a board between the wheel and the suspension.
The two fastening bolts, which are located on the back side, must be unscrewed using a socket or spanner. You first need to feel the second bolt with your hand, because you won’t see it right away. The next step is to unscrew the two guide pins. It’s worth warning right away that you shouldn’t even try to unscrew them using a simple ring wrench No. 7. In this case, it is best to take two keys, and ideally use a long 7-mm socket.
It would be useful to remind you that these pins are screwed into the hub. They simply pass through the brake disc and press it against the hub. They must also be installed when putting on the wheel during its replacement. It will be useful to treat these pins on both sides with WD. It is recommended to shed the fitting diameter of the braking distance on the hub.
Unscrewing the pins is not an easy task. If you have successfully completed this stage, you can consider that half of the work is already done. The level of difficulty in manipulating the pins depends on the mileage of the car. For example, if the indicator does not exceed 20 thousand kilometers, it will not be difficult to unscrew the pins. With a mileage of, for example, 55 thousand kilometers, difficulties may arise with dismantling parts.
Granta 41 1 new size
Through the caliper window we estimate the thickness of the brake pads.
We replace the brake pads of both front wheels if the thickness of the friction lining of any of the pads has reached the maximum permissible value - 1.5 mm.
Rotating the brake disc, inspect its working surfaces on both sides. There should be no cracks or deep grooves on the working surfaces of the disc.
Replacing front brake discs
The replacement algorithm includes the main steps:
- it is necessary to remove the wheel and jack up the car;
- the old brake pads are removed - to do this, the guide bolts are unscrewed and the caliper is folded back;
- The bracket is carefully hung on the suspension, after which you can begin to remove the disk - two nuts are unscrewed;
- if for some reason the disk cannot be removed from the bolts, you need to lightly hit it with a hammer from the reverse side;
- The new disk is carefully installed.
The nuts are screwed into place. It is advisable to pre-lubricate the threads with graphite lubricant. This will prevent souring. It is advisable to change the pads along with the discs.
Granta 41 2 new size
Using a caliper we measure the thickness of the disk, which should be at least 17.8 mm.
If, as a result of wear, a high shoulder has formed on the maximum diameter of the disk, which prevents an accurate measurement, remove the shoulder using a file or other method, or measure the thickness of the disk with a micrometer. We replace a brake disc with defects in the working surfaces or extreme wear.
The degree of wear of the brake pads of the rear wheel is assessed by the condition of the front pad, which wears out faster than the rear one.
Reasons for replacing spare parts
One of the main reasons for replacing brake discs is natural wear and tear. In addition, it is recommended to install new parts instead of old elements in the following cases:
- premature failure of discs, which can be determined by deterioration in the quality of braking of the car;
- damage to product surfaces;
- deformation of spare parts.
Attention! In any of these cases, it is recommended to replace the brake discs to avoid a dangerous situation while the vehicle is moving.
Video - When to change brake discs
Granta 41 5 new size
...and through the window we assess the condition of the front brake pad lining.
If the lining thickness is less than 1.5 mm, the brake pads of both wheels must be replaced.
To check the condition of the wheel cylinders and brake drums of the rear wheels, remove the drums (see “Replacing the brake pads of the rear wheels”).
There should be no cracks or chips on the drums. If the working surface is severely worn, or if there are grooves, we replace the brake drum.
To check the condition of the wheel cylinder sealing collars, one by one on each side...
Granta 42 2 new size
We inspect the pressure regulator in the brake mechanisms of the rear wheels and its drive.
The regulator and drive must not be damaged; brake fluid must not leak from the regulator and brake pipes. The regulator piston should not be jammed - when the brake pedal is pressed, the regulator rod should move.
Inspect the parking brake cables. There should be no damage to the sheaths on the cables. Cables in sheaths must move freely, without jamming. We replace defective cables with new ones. You also need to replace the cables if they are stretched so much that the parking brake cannot be adjusted.
We check the functionality of the parking brake. If necessary, adjust the parking brake .
The parking brake should hold the vehicle on a 23% grade.
The full travel of the parking brake lever should be from 2 to 4 teeth (clicks) of the lever ratchet device.
To adjust the parking brake, place the car on an inspection ditch or overpass and lower the parking brake lever.
How does the Lada Granta brake system work?
The working brake system is dual-circuit. This was done to ensure fault tolerance. If one of the circuits malfunctions, the second will perform braking, albeit with less efficiency. The first circuit is located on the front right and left rear wheels, and the second circuit is on the front left and right rear wheels.
The front brake discs on the Lada Granta are ventilated discs. When you press the brake pedal, the pressure in the system increases, the piston moves, pressing the pad against the disc.
To reduce cost, the rear brakes are drum brakes. They have a mechanism for automatically adjusting the gap between the drum and the pads. The disadvantage of this design is instability to moisture and souring of the brake cylinder. Only replacement helps. The Lada Granta Sport uses rear brake discs, but they are not ventilated.
The engineers took the handbrake from the VAZ-2109 car and did not modify it in any way. It also doesn't hold well and needs to be tightened frequently. To do this, there is an adjusting nut on the handbrake lever. The design is very primitive - a cable runs from the lever to the rear drum brakes.
Granta 42 4 new size
Holding the adjusting nut of the cable end with a 13mm wrench, use a head of the same size to unscrew the locknut.
Rotate the adjusting nut clockwise to tighten the cables.
It is convenient to adjust the tension of the cables with a high head with a ratchet and an extension. In this case, we do not completely unscrew the locknut, but, having aligned its edges with the edges of the adjusting nut, put on the high head “13” and rotate both nuts at once.
Use a locknut to secure the adjusting nut. When the lever is lowered, the suspended rear wheels should rotate freely.
More information about the design, maintenance and repair of Lada Granta can be found in our Wikipedia (link)
Lada Granta: checking the brake system
Replacing rear brake discs
The algorithm for replacing rear brake discs is as simple as the front ones. The process is similar. Its main stages:
- it is necessary to remove the wheel to gain access directly to the part - the car is raised on a jack or lift;
- the caliper is removed along with the pads - you can place it side by side or hang it on a spring;
- use an open-end wrench to unscrew two nuts;
- a new disk is installed.
Assembling the caliper, installing the pads - everything is done in the reverse order. It is necessary to ensure that the thickness of the brake disc corresponds to that specified by the manufacturer. If you have difficulty removing the pads, you need to press in the cylinder with a screwdriver. If difficulties arise with unscrewing threaded connections, you need to use WD-40.
Serviceable brake discs affect the driving comfort, vehicle speed and safety. It is necessary to carry out timely inspection and repair of the main components of the brake system.
Source zapchasti.expert
