Booster HONDA CIVIC 2003 7.G User Guide

Component Location Index
FRONT BRAKESFront Brake Pads, Inspection andReplacement, page 19-1 1Front Brake DiscInspection, page 19'13Front Brake CaliperOverhaul, page 19-14
INDICATORBrake System Indicator CircuitDiagram, page 19-9Parking Brake SwitchTest, page 19 10Brake Fluid Level SwitchTest, page 19-10
BRAKE CABLE
BRAKE BOOSTERBrake BoosterTest, page 19-18Brake EoosterReplacement, page 19 19
Parking Brake CableReplacement, page 19 26
REAR DISC BRAKERear Brake Pads Inspection andReplacement, page l9-20Rear Brake DiscInspection, page 19'22Rear Brake Caliper Overhaul,page 19'23
PARKING BRAKE LEVERParkino BrakeCheck and Adjustment, page 19-7
BRAKE PEDALBrake Pedal and Erake Pedal Position SwitchAdjustment, page l9-6
BRAKE HOSES and LINESBrake Hoses and LinesInspection, page 19 24Brake HosesReplacement, page 19 25
MASTER CYLINDERMaster CylinderFl6^1.^6m6nr ^2^o 1O-18Master Cylinder Inspection, page 19-16Brake Booster Pushrod ClearanceAdjustment, page'19-16Brake System Bleeding, page 19-8
19-3

Gonventional Brake Components
ComponentProcedureAlso check for:
l\4aster CylinderLook for damage or signs of fluid leakage at;. Reservoir or reservoir grommets
. Line joints
. Between master cvlinder and booster
Brake HosesLook for damage or signs of fluid leakage at:. Line joints and banjo bolt connections. Hoses and lines. also inspect for twisting or
damaqe
Bulging, twisted or bent lines.
CaliperLook for damage or signs of fluid leakage at:. Piston seal. Banjo bolt connections. Bleeder screw
Seized or sticking caliper pins.
ABS l\ilodulatorLook for damage or signs of fluid leakage at:. Line joints
. Modulator
Brake System Inspection and Tests
Brake System Test
Brake pedal sinks/fades when braking
1. Start the engine, and let it warm up to operating temperature.
2. Attach a 2-inch pieceof masking tape along the bottom of the steering wheel, and draw a horizontal reference
mark across it.
With the transmission in Neutral, press and hold the brake pedal lightly, then release the parking brake.
While still holding the brake pedal, hook the end of the tape measure behind it. Then pull the tape up to the
steering wheel, noting where the tape measure lines up with the reference mark you made on the masking tape.
Apply steady pressure to the brake pedal for 3 minutes.
Watch the tape measure.
. if it moves less than 10 mm, the master cylinder is OK.
. if it moves more than 10 mm replace the master cylinder.
t-
3.
5.
6.
19-4

Rapid brake pad wear. Vehicle vibration {after a long
drivel, or High, hard brake pedal
1. Drive the vehicle until the brakes drag or untilthe
pedal is high and hard. This can take 20 or more
brake pedal applications during an extended test
drive.
2. With the engine running, raise the vehicle on a lift,
and spin all four wheels by hand.
ls there btake drag at any of the wheels?
YES Go to step 3.
NO Look for other causes of the pad wear, high
pedal, or vehicle vibration.I
3. Turn the engine off, pump the brake pedal to
deplete the vacuum in the brake booster, and then
spin the wheels again to check for brake drag.
ls therc brake dtag at any ot the wheels?
YES-Go to step 4.
NO Replace the brake booster.I
4. Without removing the brake lines, unbolt and
separate the master cylinder from the booster, then
spin the wheels lo check for brake drag.
ls there btake drag at any of the wheels?
YES Go to step 5,
NO-Check the brake pedal position switch
adjustment and pedal free play.I
5. Loosen the hydraulic lines at the master cylinder,
then spin the wheels to check for brake drag.
ls there brake drag at any of the wheels?
YES Go to step 6.
NO- Replace the master cylinder.l
6. Loosen the bleeder screws at each caliper, then
spin the wheels to check for brake drag.
Is there brake drag at any of the wheels?
YES Disassemble and repair the caliper on the
wheel(s) with brake drag.l
NO Inspect brake hose (s)/line (s).
19-5

Master Cylinder Replacement
NOTE: Do not spill brake fluid on the vehicle; it may
damage the paint; if brake fluid does contact the paint,
wash it off immediately with water,
1, Remove the air cleaner assembly (A).
2, Disconnect the brake fluid level sensor connector
(A).
15 N.m{1.5 kgt.m, 11 lbt.ft)
3. Remove the clutch reservoir (B) andenginewire
harness clip (C)from the master cylinder mounting
base (D).
4. Remove the reservoir cap and brake fuid from the
reservoir.
5. Remove the reservoir (E) on the master cylinder
mountrng Dase.
6, Disconnect the brake lines (F)from the master
cylinder (G). To prevent spills, cover the hose joints
with rags or shop towels.
7. Remove the master cylinder mounting nuts {H) and
washers.
8. Remove the master cylinder from the brake booster.
Be careful not to bend or damage the brake lines
when removing the master cylinder.
9. Remove the rod seal (l) from the master cylinder.
10. Installthe master cylinder in the reverse order of
removal, and note these items:
. Replace all the rubber parts with new ones
whenever the master cylinder is removed.
. Check the pushrod clearance before installing the
master cylinder. and adjust it if necessary (see
page 19-16).. Use a new rod seal on reassemblY. Coat the inner bore lip and outer circumference
of the new rod seal {A) with the recommended
seal grease in the master cylinder set.
. Installthe rod seal ontothe master cylinder with
its grooved side (B)toward the master cylinder.
. Check the brake pedal height and free play after
installing the master cylinder, and adjust it if
necessary (see page 19-6).
19-15

Conventional Brake Components
Master Cylinder Inspection
NOTE:. Before reassembling, check that al I parts are f ree ofdust and other foreign particles.. Do nottryto disassemblethe mastercylinder
assembly. Replace the master cylinder assembly witha new part if necessary.. Do not allow dirt or foreign matter to contaminate thebrake fluid.
RESERVOIB CAPI unecK Ior otocKageof vent holes.
RESERVOIR
,--l RESERvOIR SEALCheck lor damaoe
RESERVOIR HOSESInspect hoses fordamage, leaks, anddeterioration.
r',,.J\+
v
MASTER CYLINDERCheck for leaks, rust, and damage
and deterioration.
STRAINERRemove accumulatedseotment.
19-16
Brake Booster Pushrod Clearance
Adjustment
SpecialTools Required
Pushrod adjustment gauge 07JAG-SD40100
NOTE: Brake booster pushrod-to-piston clearance mustbe checked and adjustments made, if necessarV, beforeinstalling the master cylinder.
1. Setthespecial tool (A) onthe mastercylinder bodv(B), push in the center shaft (C) until the top of itcontacts the end of the secondary piston {D) byturning the adjusting nut (E).
Without disturbing the center shaft's position,
installthe specialtool (A) backwards on the booster.
Install the master cylinder nuts (B), and tighten
them to the specified torque.
Connecl the booster in line with a vacuum gauge
{C) 0-101 kPa {0'-760 mmHg, 30 in.Hg) to thebooster's engine vacuum supply, and maintain anengine speed that will deliver 66 kPa (500 mmHg,20 in.Hg) vacuum.
15 N m {r.511 tbf.ftl

5. With a feeler gauge (A), measure the clearance
between the gauge body and the adjusting nut (B)
as snown,
lf the clearance between the gauge body and the
adjusting nut is 0.4 mm (0.02 in.), the pushrod-to-
piston clearance is 0 mm. However. if the clearance
between the gauge body and the adjusting nut is
0 mm, the pushrod-to-piston clearance is 0 4 mm
{0.02 in.) or more. Therefore it must be adjusted
and rechecked.
Clearance: 0-0./t mm (0-0.02 in.)
lf the clearance is incorrect, loosen the star locknut
(A). and turn the adjuster (B) in or out to adjust.
. Adjust the clearance while the specified vacuum
is appiied to the booster.. Hold the clevis (C) while adjusting.
A0 0.4 mm l0 -0.02 in.) 22N.n
07JAG-SO40100
7. Tighten the star locknut securely.
8. Remove the special tool (D).
9. Check the pushrod length (A) asshownifthe
booster is removed, lf the length is incorrect,
loosen the pushrod locknut (B), and turn the clevis
(C) in or out to adjust.
A116 mm {4.6 in.)
10. Installthe master cylinder (see page l9-15)
10 x 1.0 mm1.5 N'm11.5 kgf.m,11 lbf.ftl
19-17

Gonventional Brake Components
IBrake Booster Test
Functional Test
1. With the engine stopped, press the brake pedal
several times to deplete the vacuum reservoir, thenpress the pedal hard, and hold itfor 15 seconds. lfthe pedal sinks, either the master cylinder is
bypassing internally, or the brake system (master
cylinder, lines. modulator, or calipers) is leaking.
2. Start the engine with the brake pedal pressed. lf thepedal sinks slightly, the vacuum booster is workingproperly. lf the pedal height does not vary, thebooster or check valve is faulty.
3. With the engine running, press the brake pedal
lightly. lfthe brake pedal sinks more than 1O mm
{3/8 in, ) in 3 minutes, the master cylinder is faulty.A slight change in pedal height when the Ay'C
compressor cycles on and off is normal. (The A,/C
compressor load changes the vacuum available tothe booster.)
Leak Test
1. Press the brake pedal with the engine running, thenstop the engine. lf the pedal height does not vary
while pressed for 30 seconds, the vacuum boosteris OK. lf the pedal rises, the booster is faulty.
2. With the engine stopped, press the brake pedal
several times using normal pressure. When thepedal is first pressed, it should oe row.
On consecutive applications, the pedal height
should gradually rise. lfthe pedal position does notvarv, check the booster check valve.
19-18
3. Disconnect the brake booster vacuum hose (check
valve built-in) (A) at the booster side.
5.
4.Start the engine, and let it idle. There should bevacuum available. lf no vacuum is available, thecheck valve is not working properly. Repiace thebrake booster vacuum hose and check valve, andrelesI.
Reconnect the brake booster vacuum nose.
Start the engine, and then pinch the brake boostervacuum hose between the check valve and thebooster,
Turn the ignition switch OFF, and wait 30 seconds,Press the brake pedal several times using normalpressu re,
When the pedal is first pressed, it should be low.On consecutive applications, the pedal height
should gradually rise.
. lf the pedal position does notvary, replacethe
brake booster.. lf the pedal position varies, replace the brake
booster vacuum hose/check valve assembly.

Brake Booster Replacement
1.Remove the master cylinder (see page 19-15).
Remove the master cylinder brake lines {A) from
the brake line clip.
c
6x1.0mm9.8 N.m(1.0 kgf.m,7.2 tbf.ft)
Remove the vacuum hose mounting bracket (B).
Disconnect the vacuum hose {C) from the brake
booster.
'-/
.,.,....
alu
i '..
5. Remove the clip (A) and the joint pin (B). and
disconnectthe yoke from the brake pedal.
7.
{'l.3 kgf.m,9 lbf.ftl
Remove the brake booster mounting nuts (C).
Remove the brake booster (A)from the engine
comparlmenr.
INdAdEI. Be careful not to damage the booster
surfaces and threads of the booster stud
bolts.. Be careful not to bend or damage the
brake lines.
lnstallthe brake booster in the reverse order of
removal, and note these items:
. Adjust the pushrod clearance before installing
the brake booster (see page 19-16).. Use a new clip whenever installing.. After installing the brake booster and master
cylinder, fill the reservoir with new brake fluid,
bleed the brake system (see page 19-8), and
adjust the brake pedal height and free play (see
page 19-6),
19-19