GREAT WALL SO COOL 2006 Service Manual

BR-10Brake System
Vacuum Booster
Vacuum booster
Disassembly of Vacuum Booster
1. Take apart the master cylinder
2. Tear down the vacuum hose from the vacuum booster
3. Tear down the return spring
4. Tear down the clamping pin and U-shaped clamping pin
5. Tear down the vacuum booster, sealing washer and U-
shaped clamping head
U-shaped clip head
shock pad
adjusting shim
shock pad
vacuum booster
front three-way valve master cylinder bodybracket
one-way valve
sealing liner
Disassembly of Vacuum Booster

BR-11Brake System
Vacuum Booster
Inspection on Vacuum booster parts
Operation for one-way valve inspection
(Gasoline engine)
(a) Tear down the one-way valve;
(b) Check the air to see whether it flows from the vacuum
booster side toward the engine side.
(c) Check the air, change the one-way valve if the air flows
from the side of engine toward the vacuum booster.
(d) Mount the one-way valve in the right place.
(a) Tear down the one-way valve from the vacuum pipe.
(b) Check the air to see whether it flows from the side of
vacuum room to the hose.
(c) Check the air, and change the one-way valve if the air
flows to the hose to the vacuum room.
air
engine side booster side
air airless
air
hose side vacuum side
airairless
Mount of Vacuum Booster
1. Adjust the length of vacuum booster pushrod:
(a) Mount the sealing washer on the master cylinder;
(b) Put SST on the sealing washer and descend the pin rod
until it contact lightly the piston with its top;
(c) Put top of SST downward ,and mount it on the vacuum
booster.
(d) Check the clearance between the vacuum booster pushrod
and the head of pin on SST.
(e) Adjust the length of vacuum booster pushrod until the
pushrod touches the pinhead.
2. Mount the vacuum booster, sealing washer and Ushaped
clip head.
(a) Mount the vacuum booster and sealing washer.
(b) Mount the U-shaped clip head.
(c) Mount and tighten the assembling nuts of vacuum booster.
3. Connect the U-shaped clip head and the brake pedal:
Encase the U-shaped clamping pin in the hole of U-shaped clip
head and the brake pedal, and then mount the spring pin on the
U-shaped clamping pin.SST
washer
SST
(Diesel engine)

BR-12Brake System
Vacuum Booster
4. Mount the pedal return spring.
5. Mount the brake master cylinder
(see Page BR-8)
6. Connect the hose and the vacuum booster.
7. Fill the oil cup with brake liquid and exhaust the air in
braking system.
(see page BR-6)
8. Check the liquid leakage;
9. Check and adjust the brake pedal
(See page BR-5)
10. Check the operation
(See Page BR-6)

BR-13
Front Brake
Element figure
No. 2 lock plate of brake padNo. 1 lock plate of brake pad
silent pad cluster
brake pad assembly
silent pad cluster
caliper body
No. 2 lock plate of
brake pad No. 1 lock plate of
brake pad
long sliding caliper liner
sliding sleeve dust cover
caliper body
rectangular sealing ring
piston piston dust cover
piston dust cover
snapping spring
sliding sleeve dust cover
short sliding caliper linershort sliding caliper sleevesliding sleeve dust cover vent screwvent screw dust cover
long sliding caliper sleeve
sliding sleeve dust cover
DrBraking System
Front Brake (Dr)

BR-14
Brake pad change
Remark: Check the thickness of the friction material of brake
pad through the observation hole on caliper body after the
vehicle covers thirty thousand; if the thickness fails to fall
within the specified range, change is required. (If the brake is
used often, the thickness of friction materials of brake
pad is required to check whether it is within the specified
range after the vehicle covers more than ten thousand,
if not, change it.
1. Tear down the front wheel;
2. Check the thickness of friction material of brake pad:
Check the thickness of friction material of brake pad through
the observation hole on caliper body, if it fails to be within the
specified range, change it.
Min thickness: 2.0mm
3. Raise the wheel-brake cylinder:
(a) Tear down the short bolts of sliding sleeve;
(b) Uplift the wheel brake pump and hang it with rope to
protect the brake oil pipe.
Remark: Do not loosen the brake oil pipe and the bleeding plug.
4. Tear down the following parts:
(a) Two braking pads;
(b) Two silent pad clusters;
(c) Four braking pad lock plates.
Braking System
Front Brake (Dr)

BR-15
5. Brake disc measurement
(See page BR-17)
6. Measure the radial run-out of the brake disc;
(See BR-18)
7. Mount the lock plate of brake pad.
8. Mount the new brake pad.
(a) Mount the silent pad cluster on brake pads of both the
inner and outer sides;
Remark: Pollution of oil stain or coat is not allowed on the
work faces of brake pad or brake disc.
(b) Draw out a little brake liquid from the liquid container to
prevent the brake liquid overflowing from the liquid
container;
(c) Press in the piston with the hammer lever or similar tool.
9. Mount the wheel-brake cylinder;
Mount and screw up the hex bolts (the hex bolts shall be coated
with the thread locking sealing agents.
Fastening torque
(38-50)N
m
Remark: only one brake pad can be changed in one time so as
to prevent the piston of other wheel being shot out.
Braking System
Front Brake (Dr)

BR-16
10. Mount the front wheel;
Screw up the fixing nut of wheel.
Fastening torque
(135
150)N
m
Disassembly of Wheel-brake Cylinder
1. Take apart the brake pipeline.
(a) Tear down the brake pipeline. And block the outlet with
a clean cork.
(b) Tear down the brake oil pipe bracket from the wheel-
brake cylinder.
2. Tear down the wheel-brake cylinder from the caliper
bracket.
Tear down the two hex bolts and the wheel-brake cylinder.
3. Tear down the brake pad:
(a) Two brake pad;
(b) Two silent pad cluster;
(c) Four brake pad lock plate.
Pump Disassembly of Wheel brake
1. Take apart the following parts:
(a) Two sliding sleeve;
(b) Four sliding sleeve dust cover;
(c) Two sliding liner.
Braking System
Front Brake (Dr)

BR-17
2. Tear down the piston dust cover snapping ring and the
piston dust cover;
Tear down the piston dust cover snapping ring and the piston
dust cover with screwdriver.
3. Tear down the piston from the wheel-brake cylinder:
(a) Put a wooden plate between the piston and the caliper
body.
(b) Tear down the piston from wheel-brake cylinder with the
compressed air.
Warning: Do not put your finger in front of the piston when
using the compressed air.
4. Tear down the piston sealing ring from the caliper body.
Tear down the piston sealing ring with bent needle.
Notice: the tools used shall not be sharp so as not to
scrape the piston sealing ring.
Check the front brake parts
1. Measure the thickness of brake pad liner;
Standard thickness
10.0mm
Min thickness
2.0mm
If the thickness is less than the min thickness or is unevenly
worn; change the brake pad.
2. Measure thickness of brake disc
Standard thickness
25.0mm
Min thickness
23.0mm
If the brake disc is scraped, repair it, if the brake is serious
worn to the degree that its thickness is less than the min thickness,
brake disc requires to be changed Braking System
Front Brake (Dr)

BR-18
3. Measure the bouncing value of the brake disc face;
Remark: verify the bearing is aligned correctly before
measuring.
The bouncing value of max face: 0.11mm
4. Change the brake disc according to the requirements
(a) Tear down the calipers body from the steering knuckle.
(b) Tear down the hub and the brake disc (See Page SA-11).
(c) Mount the new brake disc and screw up the connecting
bolts according to the specified torque.
Fastening torque
(60
79)N.m
(d) Mount the hub and brake disc assembly (see page SA-12);
(e) Mount the caliper bracket on the steering knuckle and
screw up the bolts according to the specified torque.
Fastening torque
(85
105)N.m
Cylinder Assembly of Wheel-brake
1. Preparation
All parts shall be washed, dried and cleared away the alien
materials before the assembly. And coat moderate vacuum
silicon base grease on the work faces of sliding sleeve dust
cover, sliding sleeve and the sliding liner; and plaster the
moderate rubber lubricant on the work faces of piston, piston
dust cover and the rectangular sealing ring.
2. Encase the piston sealing ring and piston in the caliper body;
(a) Screw the vent screw in the vent hole of calipers.
Fastening torque
(8
13)N.m
(b) Coat moderate rubber lubricant on the work face rectan-
gular sealing ring and encase the caliper body in groove.
(c) Encase the piston in the caliper body.
3. Encase the piston dust cover and the dust cover
snapping ring in the wheel-brake cylinder.
Braking System
Front Brake (Dr)

BR-19
4. Mount the sliding liner, sliding sleeve dust cover and
sliding sleeve.
(a) Encase the sliding liner and sliding sleeve dust cover in
the wheel-brake cylinder.
(b) Ensure the sliding sleeve dust cover in the ring groove of
wheel-brake cylinder hard.
(c) Encase the sliding sleeve in the sliding sleeve dust cover.
(d) Ensure the sliding sleeve dust cover in the ring groove of
sliding sleeve.
Mount of Brake Calipers
1. Mount the brake pad;
2. Mount the wheel-brake cylinder:
(a) Mount the wheel-brake cylinder;
(b) Mount and tighten the two assembling bolts (the bolts
shall be coated with the thread locking sealing agent).
Fastening torque
(38
50)N.m
3. Connect the brake pipeline.
Connect the brake pipeline with the calipers.
Fastening torque
(21
2)N.m
4. Observe the height of brake liquid level and, if
necessary, add in the brake liquid and exhaust the air
in braking system.
Notice: prevent the brake liquid from spraying on the
brake disc when exhausting air.
5. Check to see whether there is leakage of brake liquid. Braking System
Front Brake (Dr)