6.4 Hydraulic Brake

6.4.1 Specifications
6.4.1.1 Fastener Tightening Specifications

Applications

Model

Specifications

Metric (Nm)

US English (lb-ft)

Brake Master Cylinder
Retaining Nut

M8

20-30

14.8-22.2

Brake Master Cylinder Tube
Connecting Nut

M10

11-21

8.1-15.5

Brake Hose Connecting Nut

M10

11-21

8.1-15.5

Vacuum Booster U-shape Clip
Locking Nut

M10

15-25

11.1-18.5

Vacuum Booster Retaining Nut

M8

20-25

14.8-18.5

Clutch / Brake Pedal Assembly
Lower Retaining Bolt

M8 × 16

20-25

14.8-18.5

Clutch / Brake Pedal Assembly
Upper Retaining Bolt

M8 × 15

20-25

14.8-18.5

Clutch / Brake Pedal Assembly
Retaining Nut

M8

16-26

11.8-19.2

Pedal Installation Screw

M10 × 130

30-40

22.2-29.6

Pedal Installation Nut

M10

30-40

22.2-29.6

Brake System

Hydraulic Brake

6-29

6.4.2 Description and Operation
6.4.2.1 Description and Operation

Hydraulic  braking  system  includes  the  following
components:

Brake Pedal:Receives, amplifies and transmits braking system
input from the driver.

Brake Pedal Putter:Transmits amplified brake pedal input force
into the vacuum booster.

Vacuum  Booster:Braking  system  input  force  is  amplified
through the brake pedal and passed to the vacuum booster,
boosted by the vacuum brake booster and then transmitted to
the master cylinder. Vacuum booster boosts the braking force
by vacuum to help reduce the driver braking effort.

Vacuum  Hose:Used  for  transmission  of  the  vacuum  booster
required vacuum source.

Brake Master Cylinder Tank:Filled with the hydraulic brake fluid
used by the system.

Brake  Master  Cylinder:Converts  the  mechanical  input  to
hydraulic output pressure. Hydraulic pressure from the master
cylinder output assigned to the two hydraulic fluid channels,
providing braking fluid pressure to diagonal wheels.

Hard  brake  pipe  and  brake  hose:Pass  brake  fluid  flow  to
hydraulic brake system components.

Brake Wheel Cylinder:Converts the hydraulic input pressure to
mechanical output force.

System Operation

The mechanical force from the brake pedal is converted to fluid
pressure  by  the  master  cylinder,  through  the  hydraulic
electronic control unit (ie HECU) , and through the brake pipes
and hoses transferred to the braking cylinder. Brake Cylinder
then converts the hydraulic pressure to the mechanical force.
So the brake pad presses the brake disc to achieve the vehicle
braking.

Brake Fluid Level Low Warning Lamp

Instrument  cluster  detects  the  low  brake  fluid  level  (signal
circuit  low  voltage),  and  lights  up  the  brake  fluid  level  low
warning lamp.

6-30

Hydraulic Brake

Brake System

6.4.3 Component Locator
6.4.3.1 Component Locator

3

1

2

FE06-1004b

Legend

1. Brake Master Cylinder Tank
2. Vacuum Booster

3. Brake Master Cylinder

Brake System

Hydraulic Brake

6-31

6.4.4 Diagnostic Information and Procedures
6.4.4.1 Diagnostic Notes

1. Be careful when replacing various components, it may affect the brake system performance and lead to driving danger. Use

Geely genuine parts.

2. When servicing the brake system, keeping venues and parts clean is very important.

3. If  brake  fluid  leakage  is  found,  must  disassemble  components.  If  any  unusual  circumstance  is  found,  replace  with  new

components.

4. When removing brake components, wrap brake pipe joints to prevent dust, dirt and other impurities entering into the pipe.

5. When removing or installing brake pipes, do not damage or deform the brake pipes.

6. When installing brake pipes or brake hose, make sure do not distort or bend.

7. Brake hose must be away from the shock absorber oil, grease and so on.

8. After installing brake hardware, the pipes and brake hoses should not interfere with other components.

9. Do not let brake fluid adhere to the surface of the body such as painting. If the brake fluid leaks to the paint surface, promptly

remove it.

6.4.4.2 Fault Symptom Table

Symptoms

Suspected Parts

Measures / Refer to

Brake Warning Lamp Always On

1. Brake Surface

Refer  to 

6.4.4.3

 

Brake  Warning  Lamp

Always On

2. Brake Fluid Level Sensor

Refer  to 

6.4.4.3

 

Brake  Warning  Lamp

Always On

3.  Brake  Fluid  Level  Sensor  Wiring
Harness

Refer  to 

6.4.4.3

 

Brake  Warning  Lamp

Always On

Brake System Noise

1.  Brake  Pads  (Broken,  Twisted,  Dirty,
Smooth)

Refer  to  the  front  and  rear  brake
Diagnostic Information and Procedures in
the

6.2.4.1

 

Brake Pad Inspection

2. Brake caliper bracket bolts (Loose)

Check the brake caliper bracket bolts

3. Brake caliper bolts (Loose)

Check the brake caliper bolts

4. Brake disc (Front)

Refer  to 

6.2.4.5

 

Brake  Disc  Surface  and

Worn Inspection

5. Brake Disc Guide (Loose)

Refer  to  the  front  and  rear  brake
Diagnostic Information and Procedures in
the

6.2.4.3

 

Brake Guide Inspection

6. Brake Caliper Floating Pin (Worn)

Refer  to  the  front  and  rear  brake
Diagnostic Information and Procedures in
the

6.2.4.4

 

Floating  Brake  Caliper  Pin

Inspection

Brake Deviation

1. Piston (Fixed, and Block)

Refer  to  the  front  and  rear  brake
Diagnostic Information and Procedures in
the

6.2.4.2

 

Brake Caliper Inspection

6-32

Hydraulic Brake

Brake System