Chery A15 / 480 LHD model. Instruction - page 66

—Install the brake shoe and parking brake lever, and

reassemble the return spring, as shown in the
figure.

—Fix the parking brake cable on the parking brake

lever, and install the brake shoe on the brake
wheel cylinder.

—Install the lower return spring, and adjust the

return spring and the spring of wedge-shaped
block.

—Install the brake drum and rear wheel hub bearing.

—Forcefully step on the brake pedal several times to

make the friction lining of brake in place.

REPLACEMENT OF FRICTION LINING OF BRAKE

—Check whether there are some oil stains on the

surface of friction lining of brake, and use an
abrasive cloth to grind off it, if any. Replace the
friction lining of drum brake in case it is worn to
its limit, and replace it together with the brake
shoe when replacing.

Caution: The friction lining of brake shall be

from the same manufacturer and with
the same quality when it is replaced
with new one.

INSPECTION OF REAR WHEEL DRUM BRAKE

—Measure the inner diameter of brake drum, as

shown in the figure.
Standard inner diameter: 200 mm
Service limit:
201 mm

In case there are some scratches and indentions on
the inner circle of brake drum after use, reprocess
the inner circle on a lathe.

Caution: The inner diameter shall not be greater

than the service limit when the inner
circle is reprocessed on the lathe.


—Measure the thickness of friction lining, as shown

in the figure.

Caution: The service limit is 2 mm.


—Check the contact between the friction lining of

brake and the brake drum, as shown in the figure.



MAINTENANCE OF BRAKE WHEEL CYLINDER

—Check the oil leakage of brake wheel cylinder, and

the damage of dust boot.

— Detach the brake wheel cylinder, and check

whether there are some scores on piston or
cylinder wall, whether the spring is broken, and
whether the oil seal is damaged. Replace the brake
wheel cylinder if any of the above is found.

MAINTENANCE OF SPRING

— Check the breakage, deformation or elastics

weakening of the spring, and replace it, if any.

STRUCTURAL DIAGRAM OF REAR WHEEL DRUM BRAKE

A15LHD

adopts the non-balanced drum brake (leading trailing shoe brake) for its rear

wheels, as shown in the figure below.

Structural Diagram of Rear Wheel Drum Brake

The piston of brake wheel cylinder pushes out the brake shoe with the force of brake

fluid to rotate it outward around the contact point of the brake shoe and the support plate
when braking, and thus the friction lining of brake shoe is pressed towards the brake drum,
which creates the brake torque to brake the vehicle.

The braking pressure disappears when the braking is released, and the brake shoe

returns back to its original position with the help of the return springs 3, 4 and 11.

1 Brake back plate

9 Support plate

2 Pin shaft

10 Rivet

17 Brake shoe with wedge-shaped

adjusting plate assy.

3 Return spring

11 Lower return spring

18 Friction lining

4 Brake shoe fixing spring

12 Tension spring

19 Wedge-shaped regulating plate

5 Push rod

13 Inspection hole

20 Wedge-shaped regulating block

6 Parking brake lever

14 Compression spring

7 Brake shoe assy.

15 Clamping pin

8 Support

16 Spring seat

21 Brake wheel cylinder

The braking clearance of rear brake is adjusted automatically. In case the braking

clearance exceeds the set value due to the shoe plate wear, the wedge-shaped regulating
block 20 located between the lever and brake shoe will move downwards with the help of
spring force of tension spring 12 to compensate the clearance increase between the lever and
wedge-shaped regulating block so as to make the brake shoe further open toward the brake
drum to compensate the friction lining wear.

RELATED PARAMETERS OF VACUUM BOOSTER AND MASTER BRAKE
CYLINDER

A15LHD series vehicle’s braking equipment adopts the 228.6mm (9in) vacuum booster and
tandem type master brake cylinder, which realizes the booster effect using the vacuum
produced by the operating engine. The vacuum chamber of the booster connects to the air
intake pipe of engine via the vacuum hose and check valve.

The master brake cylinder adopts the tandem type master brake cylinder, which consists of
the cylinder body, piston, spring, spring seat, cup and etc. The master brake cylinder
connects with the front part of the booster using two bolts. A brake fluid reservoir is installed
on the upper part of master brake cylinder. Two working chambers (primary chamber and
secondary chamber) at the front and rear are connected serially in the master cylinders.

Main technical parameters of the A15LHD brake system are:

Master brake cylinder: φ22.2 mm

Vacuum booster: Φ228.6 mm (9in)

Vacuum booster boost ratio: 3.9:1

Travel of primary chamber: 16 mm

Travel of secondary chamber: 18 mm

Diameter of wheel cylinder of front wheel disc brake: Φ 54 mm

Outer diameter of brake disc: Φ256 mm

Thickness of brake disc: 13 mm

Thickness of front friction lining: 14 mm

Diameter of brake drum of rear drum brake: Φ200 mm

Diameter of wheel cylinder of rear drum brake: Φ17.46 mm

Brake shoe of rear drum brake: Φ200 mm×40 mm ×5 mm

Front and rear braking power distribution ratio: 65% for front wheel, and 35% for rear wheel

Parking brake: Acting force of parking braking control rod (38mm from terminal) < 400 N
when parking on a ramp, with 20% full load

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