Chery A series. Manual - part 77

INDUCTION TO BRAKE SYSTEM

A15LHD is equipped with a diagonally split dual-circuit vacuum-assisted hydraulic brake
system, which consists of service brake and parking brake. A disc brake is used for the front
wheels, while a drum brake is for the rear wheels. And the servo system adopts the
high-performance vacuum booster and dual-circuit hydraulic master brake cylinder.

A15LHD is also equipped with an Anti-lock Brake System (ABS) which considerably
improves the direction control and brake performance of the whole vehicle when braking.
The ABS system is available to prevent the wheels from being locked up; what’s more, it can
maximize the longitudinal adhesion of tires. That is how the ABS system doesn’t only ensure
the steer ability of front wheels, but also avoids the sideslip of rear wheels, and therefore can
ensure the vehicle to be braked under the condition of maximum adhesion coefficient of road
surface.

And the parking brake control mechanism, which applies a cable featuring with the
protective cover and low frictional resistance to directly control the drum brake lever of the
two rear wheels, is located between the two front seats. The rear wheel brake also serves as a
parking brake, which features with the simple structure and high efficiency.

DIAGONALLY-SPLIT DUAL-CIRCUIT BRAKE

A15LHD adopts the diagonally-split dual-circuit brake system, the front chamber of master
brake cylinder of which is connected to the left front wheel brake and the rear right brake;
and the rear chamber of master cylinder to the front right and rear left wheel brakes. This
simple structure ensures 50% of normal brake force maintained in case of the failure of any
one of the two circuits, that is, no matter which any circuit fails, the basic brake requirements
are still met by the other circuit.

The A15 RHD brake system is shown in the figure below.

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Brake System of A15LHD

1 Brake master cylinder 

4 Brake pedal

7 Front disc brake

2 Brake fluid reservoir 

5 Brake pipeline

3 Vacuum booster

6 Rear drum brake

REGULAR BRAKE SYSTEM

AIR BLEEDING

Warning:

*   The proper fluid level shall be kept inside the brake fluid reservoir when air
bleeding.

Specified fluid type: DOT3 or DOT4

Caution: The brake system shall bleed air once one of brake pipelines disconnects. If

one of hydraulic pipes disconnects from the master cylinder, the air bleeding
starts from the wheel cylinder most away from the brake master cylinder, and
then from the next wheel cylinder till all the four wheel cylinders bleed air. If
the disconnection point is a point other than the one at the master cylinder, the
air bleeding shall start from the wheel cylinder nearest the disconnection
point, and then from the next cylinder till all the four-wheel cylinders bleed
air.

*   Remove the oil drain plug, and fix a vinyl insulating sleeve on the thread of oil drain plug

hole.

*   Put the other end of the vinyl insulating sleeve into a clean container available to fill the

fluid.

*   Step down the brake pedal several times, and then keep it in the position.

INSPECTION OF THE CHECK VALVE OF VACUUM HOSE

Check the following contents after air bleeding:

*   Operation of brake

*   Oily fluid leakage

*   Fluid Level

To Engine

Check Valve

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Inspection of the check valve of vacuum hose (power assisted brake unit)

*   Detach the clips and vacuum hoses

*   Pump the engine-side hoses and apply the pressure force on it, and verify that the air

blows only to this side.

*   If there are air flow in the both directions or not air flow at all, Replace the vacuum hose

.

ADJUSTMENT AND MAINTENANCE OF BRAKE PEDAL

*  Adjustment of Clearance between Brake

Pedal and Floor

-- Operate the brake pedal 7 with a 300 N force as

shown in the figure. The clearance between the
brake pedal 7 and floor 8 shall not be less than 80
mm.

-- If the clearance is less than the limit value, firstly

remove the spring locking piece 9 which is used
to connect the vacuum booster 4 with the brake
pedal 7, then pull out the pin 10, unscrew the lock
nut 6 and adjust the push rod fork 5 until the
requirement is met.

*   Adjustment of Brake Pedal Free Travel

-- Shut down the engine and step on the brake pedal several times to remove the vacuum

kept in the vacuum booster.

-- Press down the brake pedal by hand until the resistance is felt, in this case, the pressed

distance is the free travel of brake pedal, the required value of which is 3 to 6 mm.

-- In case the free travel is less than the required value, adjust the clearance between the

vacuum booster push rod and the master brake cylinder.

Caution: The free travel of brake pedal shall not be shortened due to the carpet laid on

the floor, otherwise the brake travel shortened may cause the brake
performance decrease, even disable the brake.

1. Nut

7. Brake pedal

2. Brake master
cylinder

8. Floor

3. Check valve
of vacuum hose

9. Spring
locking piece

4. Vacuum
booster

10. Pin

5. Push rod fork

11. Push rod

6. Lock nut

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*   Maintenance of Brake Pedal
-- Check the smooth operation of brake pedal, and remove it for inspection if its operation is

abnormal. Check whether the brake pedal is distorted or deformed, and replace it if any.

-- Check whether the brake pedal shaft is worn seriously or deformed, and replace it if any.

All shaft pins shall be lubricated when assembling.

DISASSEMBLY/ASSEMBLY AND INSPECTION OF FRONT WHEEL DISC BRAKE

REMOVAL AND INSTALLATION OF FRONT WHEEL DISC BRAKE

Removal:

-- Lift up the vehicle and remove the front wheel.

-- Loosen and remove the fixing bolt (where the

arrow points).

-- Detach the caliper housing and then remove the

brake lining.

Install it in the reverse order of removal.
Installation:

-- The brake lining with a larger friction surface shall

be installed outside when installing the brake
block.

-- The brake linings on both sides shall be replaced

at the same time with the products provided by the
same one manufacturer when replacing.

-- The tightening torque of securing bolt shall be

25±2Nm   (as shown in the figure).

-- The tightening torque of wheel bolt shall be

110±10Nm.

-- The brake disc shall be replaced when the wear

limit of 10 mm reaches. Remove the caliper
housing firstly before replacing the brake disc.
Remove the dirt and anti-rust oil on the friction
surface of new brake disc before it is installed.

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