DAEWOO MATIZ 2003 Service Repair Manual

4C – 2 POWER BOOSTER
DAEWOO M-150 BL2
DESCRIPTION AND OPERATION
POWER BOOSTER
This booster is a single diaphragm, vacuum-suspended
unit. In a normal operating mode, with the service brakes
in the release position, a vacuum-suspended booster
operates with a vacuum on both sides of its diaphragm.
When the brakes are applied, air at atmospheric pres-
sure is admitted to one side of the diaphragm to pro-vide the power assist. When the brakes are released, at-
mospheric air is shut off from that side of the diaphragm.
The air is then drawn from the booster through the vacu-
um check valve by the vacuum source.
Important: If any hydraulic component is removed or
disconnected, it may be necessary to bleed all or part of
the brake system.

POWER BOOSTER 4C–3
DAEWOO M-150 BL2
DIAGNOSTIC INFORMATION AND PROCEDURES
POWER BOOSTER FUNCTIONAL
CHECK
1. With the engine stopped, eliminate the vacuum in the
booster by pumping the brake pedal several times.
2. Push the pedal down and hold it in this position.
3. Start the engine.
4. The booster is OK if the pedal drops further because
of extra force produced.
If the brake pedal does not drop, the vacuum system
(vacuum hoses, check valve, etc.) is probably defective
and should be checked.
If no defect is revealed by checking the vacuum system,
the defect is in the booster itself.
CHECK VALVE FUNCTIONAL CHECK
1. Remove the vacuum hose.
2. Suck the vacuum hose to power booster. And also,
suck the vacuum hose to engine.
3. If the air pass through the check valve or not, replace
the check valve. And if the vacuum hose to engine isonly sucked, the check valve OK.
D17A301B

4C –4 POWER BOOSTER
DAEWOO M-150 BL2
REPAIR INSTRUCTIONS
ON–VEHICLE SERVICE
D107A501
VACUUM HOSE AND CHECK VALVE
Removal Procedure
1. Remove the vacuum hose.

Disconnect the vacuum hose from the intake man-
ifold (1).
D17A502A

Disconnect the vacuum hose from the power
booster (2).
D107A503
Installation Procedure
1. Connect the vacuum hose to the power booster.
2. Connect the vacuum hose to the intake manifold.

POWER BOOSTER 4C–5
DAEWOO M-150 BL2
D107A519
POWER BOOSTER ASSEMBLY
(LEFT–HAND DRIVE)
Removal Procedure
1. Remove the master cylinder assembly. Refer to Sec-
tion 4B, Master Cylinder.
2. Disconnect the vacuum hose from the power booster.
3. Remove the power booster.

Straighten the cotter pin and remove it (1).

Remove the clevis pin (2).
D107A520

Remove the nuts (3).
D107A521

Remove the power booster (4).
D17A522A
Installation Procedure
1. Install the power booster with the new cotter pin, cle-
vis pin and nuts.
Tighten
Tighten the nuts to 16 Nm (12 lb-ft).
Important: Make sure the distance from the booster
to the center of the clevis bore should be 100mm
(3.94 in.).
2. Install the master cylinder assembly. Refer to Section
4B, Master Cylinder.
3. Connect the vacuum hose to the power booster.
4. Bleed the brake system. Refer to Section 4A, Hy-
draulic Brakes.

4C –6 POWER BOOSTER
DAEWOO M-150 BL2
D24C001
POWER BOOSTER ASSEMBLY
(RIGHT–HAND DRIVE)
Removal Procedure
1. Remove the master cylinder assembly. Refer to Sec-
tion 4B, Master Cylinder.
2. Disconnect the vacuum hose from the power booster.
3. Remove the instrument panel assembly. Refer to
Section 9E, Instrument/Driver Information.
4. Remove the evaporator unit mounting screws and
take off the evaporator unit a little. Refer to Section
7B, Manual Control Heating, Ventilation, and Air Con-
ditioning System.
5. Remove the power booster.

Straighten the cotter pin and remove it (1).

Remove the clevis pin (2).
D24C002

Remove the nuts (3).
D107A521

Remove the power booster (4).

POWER BOOSTER 4C–7
DAEWOO M-150 BL2
D24C003
Installation Procedure
1. Install the power booster with the new cotter pin, cle-
vis pin and nuts.
Tighten
Tighten the nuts to 16 Nm (12 lb-ft).
Important: Make sure the distance from the booster
to the center of the clevis bore should be 100mm
(3.94 in.).
2. Install the evaporator unit with the screws. Refer to
Section 7B, Manual Control Heating, Ventilation, and
Air Conditioning System.
3. Install the instrument panel assembly. Refer to Sec-
tion 9E, Instrument/Driver Information.
4. Connect the vacuum hose to the power booster.
5. Install the master cylinder assembly. Refer to Section
4B, Master Cylinder.

4C –8 POWER BOOSTER
DAEWOO M-150 BL2
SPECIFICATIONS
GENERAL SPECIFICATIONS

Application

Unit

Description
Type–

Vacuum–Suspended
Diametermm (inch)

177.8 (7) Power Booster
Servo Force Ratio–

3.7 : 1
Distance from the booster to
the center of the clevis boremm (inch)96(3.78)
FASTENER TIGHTENING SPECIFICATIONS

Application
Nm
Lb-Ft
Lb-In
Booster–to-Dash Panel Nuts

16

12

–
Master Cylinder Attaching Nuts 16 12 –

DAEWOO M-150 BL2
SECTION 4D
FRONT DISC BRAKES
TABLE OF CONTENTS
Description and Operation 4D-2. . . . . . . . . . . . . . . . . .
Disc Brake Caliper Assembly 4D-2. . . . . . . . . . . . . . .
Clearance Calibration 4D-2. . . . . . . . . . . . . . . . . . . . . .
Component Locator 4D-3. . . . . . . . . . . . . . . . . . . . . . . .
Front Disc Brakes 4D-3. . . . . . . . . . . . . . . . . . . . . . . . .
Diagnostic Information and Procedures 4D-4. . . . .
Front Disc Brake 4D-4. . . . . . . . . . . . . . . . . . . . . . . . . .
Lining Inspection 4D-5. . . . . . . . . . . . . . . . . . . . . . . . . .
Rotor Inspection 4D-5. . . . . . . . . . . . . . . . . . . . . . . . . . .
Repair Instructions 4D-6. . . . . . . . . . . . . . . . . . . . . . . . On-Vehicle Service 4D-6. . . . . . . . . . . . . . . . . . . . . . . . . .
Shoe and Lining 4D-6. . . . . . . . . . . . . . . . . . . . . . . . . . .
Caliper Assembly 4D-7. . . . . . . . . . . . . . . . . . . . . . . . . .
Rotor 4D-7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Unit Repair 4D-8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Caliper Overhaul 4D-8. . . . . . . . . . . . . . . . . . . . . . . . . .
Specifications 4D-11. . . . . . . . . . . . . . . . . . . . . . . . . . . .
General Specifications 4D-11. . . . . . . . . . . . . . . . . . . .
Fastener Tightening Specifications 4D-11. . . . . . . . . .

4D – 2 FRONT DISC BRAKES
DAEWOO M-150 BL2
DESCRIPTION AND OPERATION
DISC BRAKE CALIPER ASSEMBLY
This caliper has a single bore and is mounted to the
steering knuckle with two mounting bolts. Hydraulic
pressure, created by applying the brake pedal, is con-
verted by the caliper to a stopping force. This force acts
equally against the piston and the bottom of the caliper
bore to move the piston outward and to slide the caliper
inward, resulting in a clamping action on the rotor. This
clamping action forces the linings against the rotor,
creating friction to stop the vehicle.
D17B001A
Important:

Replace all components included in the repair kits
used to service this caliper.

Lubricate the rubber parts with clean brake fluid to
ease assembly.

Do not use lubricated shop air on brake parts, as
damage to the rubber components may result.

If any hydraulic component is removed or discon-
nected, it may be necessary to bleed all or part of the
brake system.

Replace the pads in axle sets only.

The torque values specified are for dry, unlubricated
fasteners.

Perform the service operations on a clean bench, free
from all mineral oil materials.
CLEARANCE CALIBRATION
When the hydraulic pressure is applied to the piston, the
piston moves leftward. The piston seal, which extent
considerable pressure against the piston, moves with
cylinder.
However, as a part of the piston seal is fixed into a grove
in the cylinder shape of the seal is as shown in below
figure, distorted toward the piston moving direction.
When the pressure is taken off from the brake pedal and
the hydraulic pressure is released from the piston, a re-
storing elastic force is generated at the seal and pushes
the piston rightward and back it in original position.
As the pads wear away and the clearance between rotor
and pads becomes larger, the piston moves larger.
The seal then could change in shape further, but since
end of the seal is fixed into the groove in the cylinder, the
distortion is limited to the same amount as previously
described.
The piston moves further to cover the distance of clear-
ance. As the piston returns by the same distance and
the rubber seal recovers its original shape, the clear-
ance between the rotor and pads is maintained in origi-
nal condition.
1. Piston
2. Piston Seal
3. Pads
a. Clearance
D107B002

FRONT DISC BRAKES 4D–3
DAEWOO M-150 BL2
COMPONENT LOCATOR
FRONT DISC BRAKES
D17B401A
1. Front Brake Caliper Assembly
2. Front Brake Boot Assemblies
3. Pins
4. Pin Boots
5. Front Brake Pads
6. Carrier
7. Pad Spring8. Piston Boot
9. Piston
10. Piston Seal
11. Cylinder
12. Bleeder Screw Cap
13. Bleeder Screw