service DAEWOO LACETTI 2004 Service Manual Online

SECTION : 4C
POWER BOOSTER
TABLE OF CONTENTS
SPECIFICATIONS4C–1 . . . . . . . . . . . . . . . . . . . . . . . . . .
Fasrener Tightening Specifications 4C–1. . . . . . . . . .
DIAGNOSIS4C–1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Power Booster Functional Check 4C–1. . . . . . . . . . . .
MAINTENANCE AND REPAIR4C–2 . . . . . . . . . . . . . . . ON–VEHICLE SERVICE 4C–2. . . . . . . . . . . . . . . . . . . . .
Vacuum Hose 4C–2. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Power Booster Assembly 4C–2. . . . . . . . . . . . . . . . . . .
GENERAL DESCRIPTION AND SYSTEM
OPERATION4C–6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Power Booster 4C–6. . . . . . . . . . . . . . . . . . . . . . . . . . . .
SPECIFICATIONS
FASRENER TIGHTENING SPECIFICATIONS
ApplicationNSmLb–FtLb–In
Booster–to–Bracket Nuts (Right–Hand Drive)2216–
Booster–to–Dash Panel Nut (Left–Hand
Drive)2216–
Booster Hex Nut and Pushrod Clevis1813–
Brake Line Fittings1612–
DIAGNOSIS
POWER BOOSTER FUNCTIONAL
CHECK
1. With the engine stopped, eliminate vacuum in the
booster by pumping the brake pedal several times.
2. Push the pedal down and hold in this position.
3. Start the engine.4. The booster is OK if the pedal drops further be-
cause of extra force produced.
If the brake pedal does not drop, the vacuum system (vac-
uum 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.

4C – 2IPOWER BOOSTER
DAEWOO V–121 BL4
MAINTENANCE AND REPAIR
ON–VEHICLE SERVICE
VACUUM HOSE
Removal Procedure
1. Spread the clip on the vacuum hose connection at
the intake manifold and move the clip slightly to-
ward the brake booster.
2. Pull the hose from the union nut connection. If the
hose does not remove easily or is deteriorated, pry
off and discard the hose.
3. Spread the clip on the vacuum hose connection to
the brake booster, and move the clip clear of the
booster.
4. Remove the vacuum hose.
Installation Procedure
1. Mount the vacuum hose and ensure the connec-
tions are tight on each end.
2. Check the function of the booster. Refer to the
”Power Booster Functional Check” in this section.
POWER BOOSTER ASSEMBLY
Removal Procedure
1. Remove the master cylinder. Refer to Section 4B,
Master Cylinder Assembly.

SECTION : 4D
FRONT DISC BRAKES
TABLE OF CONTENTS
SPECIFICATIONS4D–1 . . . . . . . . . . . . . . . . . . . . . . . . . .
Fastener Tightening Specirications 4D–1. . . . . . . . . .
DIAGNOSIS4D–1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lining Inspection 4D–1. . . . . . . . . . . . . . . . . . . . . . . . . .
Rotor Inspection 4D–1. . . . . . . . . . . . . . . . . . . . . . . . . .
MAINTENANCE AND REPAIR4D–3 . . . . . . . . . . . . . . .
ON–VEHICLE SERVICE 4D–3. . . . . . . . . . . . . . . . . . . . .
Shoe and Lining 4D–3. . . . . . . . . . . . . . . . . . . . . . . . . . Caliper Assembly 4D–3. . . . . . . . . . . . . . . . . . . . . . . . . .
Rotor 4D–4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Splash Shield 4D–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
UNIT REPAIR 4D–6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Caliper Overhaul 4D–6. . . . . . . . . . . . . . . . . . . . . . . . . .
GENERAL DESCRIPTION AND SYSTEM
OPERATION4D–9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Disc Brake Caliper Assembly 4D–9. . . . . . . . . . . . . . . .
SPECIFICATIONS
FASTENER TIGHTENING SPECIRICATIONS
ApplicationNSmLb–FtLb–In
Brake Hose Inlet Fitting–to–Caliper Bolt4030–
Caliper Bleeder Valve8–71
Caliper–to–Steering Knuckle Mounting Bolts9570–
Retaining Frame–to–Caliper Housing Bolts2720–
Rotor–to–Front Wheel Hub Detent Screw4–35
Splash Shield–to–Steering Knuckle Screws4–35
DIAGNOSIS
LINING INSPECTION
1. Raise and suitably support the vehicle.
2. Remove the front wheels. Refer to Section 2E,
Tires and Wheels.
3. Visually check the linings for minimum thickness
and wear.
4. Measure the thickness.
Important : The minimum thickness of the inner or the
outer pad is 7 mm (0.28 inch).
5. Install the brake pads in axle sets only.
6. Install the front wheels. Refer to Section 2E, Tires
and Wheels.
7. Lower the vehicle.ROTOR INSPECTION
Thickness variation can be checked by measuring the
thickness of the rotor at four or more points around the cir-
cumference of the rotor. All measurements must be made
at the same distance in from the edge of the rotor.
A rotor that varies by more than 0.01 mm (0.0004 inch) can
cause pedal pulsations and/or front end vibration during
brake applications. A rotor that does not meet these speci-
fications should be refinished to specifications or re-
placed.

FRONT DISC BRAKES 4D – 3
DAEWOO V–121 BL4
MAINTENANCE AND REPAIR
ON–VEHICLE SERVICE
SHOE AND LINING
Removal Procedure
1. Raise and suitably support the vehicle.
2. Remove the front wheels. Refer to Section 2E,
Tires and Wheels.
3. Remove the lower bolt of the caliper assembly re-
taining frame.
Important : Caliper assembly removal is not necessary to
service the brake pads.
4. Pull the caliper piston housing up.
5. Remove the brake pads.
Installation Procedure
1. Measure the minimum lining thickness. Refer to
”Lining Inspection” in this section.
2. Install the brake pads into the caliper.
3. Push the piston inward, if needed.
Notice : Take care not to damage the piston seal when the
piston housing frame is pulled down.
4. Pull down the caliper piston housing and secure it
to the retaining frame with the lower bolt.
Tighten
Tighten the retaining frame–to–caliper housing bolts
to 27 NSm (20 lb–ft).
5. Install the front wheels. Refer to Section 2E, Tires
and Wheels.
6. Lower the vehicle.
CALIPER ASSEMBLY
Removal Procedure
1. Raise and suitably support the vehicle.
2. Mark the position of the front wheels relative to the
wheel hubs and remove the wheels. Refer to Sec-
tion 2E, Tires and Wheels.
3. Remove the bolt and the washers attaching the
brake hose to the caliper.
4. Disconnect the brake hose, and plug the openings
in the caliper and the brake hose to prevent fluid
loss and contamination.
5. Remove the caliper mounting bolts from the steer-
ing knuckle, and remove the caliper assembly.

FRONT DISC BRAKES 4D – 9
DAEWOO V–121 BL4
GENERAL DESCRIPTION
AND SYSTEM OPERATION
DISC BRAKE CALIPER ASSEMBLY
This caliper has a single bore and is mounted to the steer-
ing knuckle with two mounting bolts. Hydraulic pressure,
created by applying the brake pedal, is converted 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 ve-
hicle.Important :
S Replace all components included in the repair kits
used to service this caliper.
S Lubricate the rubber parts with clean brake fluid to
ease assembly.
S Do not use lubricated shop air on brake parts, as
damage to the rubber components may result.
S If any hydraulic component is removed or discon-
nected, it may be necessary to bleed all or part of
the brake system.
S Replace the pads in axle sets only.
S The torque values specified are for dry, unlubri-
cated fasteners.
S Perform the service operations on a clean bench,
free from all mineral oil materials.

SECTION : 4E1
REAR DISC BRAKES
TABLE OF CONTENTS
SPECIFICATIONS4E1–1 . . . . . . . . . . . . . . . . . . . . . . . . .
Fastener Tightening Specifications 4E1–1. . . . . . . . . .
DIAGNOSIS4E1–1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lining Inspection 4E1–1. . . . . . . . . . . . . . . . . . . . . . . . .
Rotor Inspection 4E1–1. . . . . . . . . . . . . . . . . . . . . . . . . .
MAINTENANCE AND REPAIR4E1–3 . . . . . . . . . . . . . .
ON–VEHICLE SERVICE 4E1–3. . . . . . . . . . . . . . . . . . . .
Shoe and Lining 4E1–3. . . . . . . . . . . . . . . . . . . . . . . . . . Caliper 4E1–4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Rotor 4E1–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Hub and Parking Brake Shoe/Backplate 4E1–6. . . . .
UNIT REPAIR 4E1–10. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Caliper Overhaul 4E1–10. . . . . . . . . . . . . . . . . . . . . . . .
GENERAL DESCRIPTION AND SYSTEM
OPERATION4E1–12 . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Disc Brake Caliper Assembly 4E1–12. . . . . . . . . . . . . .
SPECIFICATIONS
FASTENER TIGHTENING SPECIFICATIONS
ApplicationNSmLb–FtLb–In
Brake Hose Inlet Bolt and Ring Seals3224–
Caliper Mounting Bolts5641–
Lower Caliper Mounting Bolt2720–
Parking Brake Shoe Hold–Down Spring As-
sembly Screw4–35
Rotor Detent Screw4–35
Hub Bolts6548–
DIAGNOSIS
LINING INSPECTION
1. Raise and suitably support the vehicle.
2. Remove the rear wheels. Refer to Section 2E, Tires
and Wheels.
3. Visually check the brake shoe linings for minimum
thickness and wear.
4. Measure the thickness.
Important : The minimum discard thickness of the brake
shoe lining is 2 mm (0.08 inch).
5. Install the shoes in axle sets only.
6. Install the rear wheels. Refer to Section 2E, Tires
and Wheels.
7. Lower the vehicle.
ROTOR INSPECTION
Brake rotors are manufactured with close tolerances for
thickness variation, flatness, and lateral runout, but pits
and grooves are created in rotors during usage. Lack of
uniformity of the braking surfaces of the rotor can cause
inadequate braking and a pulsating pedal during braking.
The surface finish of the rotor is also important because
an unsuitable surface finish can cause pulling and rapid
wear of the brake shoe lining. If a rotor does not meet the
specification, it should be refinished to specification or re-
placed. Refinishing of the rotor should only be done with
precision equipment.
Thickness variation can be checked by measuring the
thickness of the rotor at four or more points around the cir-
cumference of the rotor. All measurements must be made
at the same distance from the edge of the rotor. A rotor that
varies by more than. 1.0 mm (0.04 inch) can cause pedal

REAR DISC BRAKES 4E1 – 3
DAEWOO V–121 BL4
MAINTENANCE AND REPAIR
ON–VEHICLE SERVICE
SHOE AND LINING
Removal Procedure
1. Raise and suitably support the vehicle.
2. Remove the rear wheels. Refer to Section 2E, Tires
and Wheels.
3. Remove the lower caliper guide pin bolt.
Important : Caliper removal is not necessary to service
the brake pads.
4. Pivot the caliper upward.
5. Remove the brake shoes.
Installation Procedure
1. Measure the minimum brake shoe lining thickness.
Refer to ”Lining Inspection” in this section.
2. Install the brake shoes into the caliper.
3. Push the piston inward, if needed.

4E1 – 12IREAR DISC BRAKES
DAEWOO V–121 BL4
GENERAL DESCRIPTION
AND SYSTEM OPERATION
DISC BRAKE CALIPER ASSEMBLY
The caliper has a single bore and is mounted to the steer-
ing knuckle with two mounting bolts. Hydraulic pressure,
created by applying the brake pedal, is converted 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 ve-
hicle.S Replace all components included in the repair kits
used to service the caliper.
S Lubricate the rubber parts with clean brake fluid to
ease assembly.
S Do not use lubricated shop air on brake parts, as
damage to the rubber components may result.
S If any hydraulic component is removed or discon-
nected, it may be necessary to bleed all or part of
the brake system. Refer to Section 4F, Anti–lock
Brake System.
S Replace the shoes in axle sets only.
S The torque values specified are for dry, unlubri-
cated fasteners.
S Perform the service operations on a clean bench,
free from oily material.

SECTION : 4E2
REAR DRUM BRAKES
TABLE OF CONTENTS
SPECIFICATIONS4E2–1 . . . . . . . . . . . . . . . . . . . . . . . . .
Fastener Tightening Specifications 4E2–1. . . . . . . . .
DIAGNOSIS4E2–1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lining Inspection 4E2–1. . . . . . . . . . . . . . . . . . . . . . . . .
Drums 4E2–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
MAINTENANCE AND REPAIR4E2–3 . . . . . . . . . . . . . .
ON–VEHICLE SERVICE 4E2–3. . . . . . . . . . . . . . . . . . . .
Brake Adjustment 4E2–3. . . . . . . . . . . . . . . . . . . . . . . . Shoe and Lining 4E2–4. . . . . . . . . . . . . . . . . . . . . . . . .
Wheel Cylinder Assembly 4E2–7. . . . . . . . . . . . . . . . .
Backing Plate 4E2–8. . . . . . . . . . . . . . . . . . . . . . . . . . . .
UNIT REPAIR 4E2–10. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Wheel Cylinder 4E2–10. . . . . . . . . . . . . . . . . . . . . . . . .
GENERAL DESCRIPTION AND SYSTEM
OPERATION4E2–12 . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Drum Brakes 4E2–12. . . . . . . . . . . . . . . . . . . . . . . . . . .
SPECIFICATIONS
FASTENER TIGHTENING SPECIFICATIONS
ApplicationNSmLb–FtLb–In
Brake Line1612–
Brake Wheel Hub/Backing Plate–to–Rear
Axle Nuts2821–
Wheel Cylinder–to–Backing Plate Bolt8–71
DIAGNOSIS
LINING INSPECTION
1. Raise and suitably support the vehicle.
2. Remove the wheel. Refer to Section 2E, Tires and
Wheels.
3. Release the parking brake.
4. Remove the drum. Refer to ” Drum” in this section.
5. Measure the lining thickness. The minimum lining
thickness is 0.5 mm (0.02 inch).
CAUTION : To avoid injury when servicing brake
parts, do not create dust by grinding or sanding the
brake linings or by cleaning the wheel brake parts
with a dry brush or with compressed air.
Important : Replace the shoe and lining assembly in axle
sets only.
6. Install the drum, if removed. Refer to ”One–Piece
Drum” or ”Two–Piece Drum” in this section.
7. Install the wheel, if removed. Refer to Section 2E,
Tires and Wheels.
8. Lower the vehicle.
DRUMS
Whenever brake drums are removed, they should be thor-
oughly cleaned and inspected to see if the drums are
cracked, scored, deeply grooved, or beyond the specified
out–of–round limit.
S A cracked drum is unsafe for further service and-
must be replaced. Do not attempt to weld a cracked
drum. Smooth out any slight scores.
S Heavy or extensive scoring will cause excessive
brake lining wear and may require refinishing the
drum braking surface.
S If the brake linings are slightly worn but are still re-
usable and the drum is grooved, polish the drum
with a fine emery cloth but do not refinish it. Elimi-
nating all grooves in the drum and smoothing the
ridges on the lining would remove too much metal
and lining. If left alone, the grooves and ridges
match, and satisfactory service can be obtained. If
the brake linings need to be replaced, refinish a
grooved drum. A grooved drum, used with a new

REAR DRUM BRAKES 4E2 – 3
DAEWOO V–121 BL4
MAINTENANCE AND REPAIR
ON–VEHICLE SERVICE
BRAKE ADJUSTMENT
Removal Procedure
1. Release the parking brake.
2. Operate the brake at least 10 times until the jump-
ing of the adjustment spring on the adjustment nut
can no longer be heard on either brake drum.
3. Raise and suitably support the vehicle.
4. Remove the rear wheels. Refer to Section 2E, Tires
and Wheels.
5. Remove the drum detent screw.
6. Remove the brake drum.
7. Using the rear brake adjuster nut, turn the adjuster
assembly in until there is a sufficient amount of
drag on the brake drum.
8. Make sure that the parking brake lever stops are
against the edge of the shoe web. If they are not,
loosen the parking brake cable at the equalizer. Re-
fer to Section 4G, Parking Brake.