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.
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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),
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