Page 1044 of 1449
35A-2
BASIC BRAKE
SYSTEM
CONTENTS
GENERAL INFORMATION 3..................
SERVICE SPECIFICATIONS 5.................
LUBRICANTS 6..............................
SEALANT 6..................................
SPECIAL TOOLS 6...........................
ON-VEHICLE SERVICE 7.....................
Brake Pedal Check and Adjustment 7............
Brake Booster Operating Test 8.................
Check Valve Operation Check 9.................
Proportioning Valve Function Test
9......................Bleeding 10....................................
Brake Fluid Level Sensor Check 11.............
Disc Brake Pad Check and Replacement 11......
Disc Brake Rotor Check 13.....................
Brake Disc Thickness Check 14.................
Brake Disc Run-out Check and Correction 14....
BRAKE PEDAL 16...........................
PROPORTIONING VALVE, MASTER
CYLINDER AND BRAKE BOOSTER 17........
Master Cylinder 19.............................
DISC BRAKE 20.............................
Page 1045 of 1449
BASIC BRAKE SYSTEM -General Information35A-3
GENERAL INFORMATION
The brake system offers high dependability and durability along with improved braking performance and
brake sensitivity.
SERVICE PRECAUTION
Take care not to contact the parts or tools to the caliper because the paint of caliper will be scratched.
SPECIFICATIONS
ItemsSpecifications
Master cylinderTypeTandem type
I.D. mm26.9
Brake boosterTypeVacuum type, tandem
Effective dia. of power cylinder mm205 + 230
Boosting ratio4.5 (Pedal depressing force: 230 N)
Rear wheel hydraulic
controlmethod
Vehicles with ABS Electronic brake-force distribution (EBD)
control methodVehicles without ABS Proportioning valves
Proportioning valves
VehicleswithoutABS
TypeSingle type¢2
Decompression ratio0.25
Front brakes
RS(standard)
TypeFloating caliper, 2 piston, ventilated disc
Disc effective dia.¢thickness mm227¢24
Wheel cylinder I.D. mm42.9 (¢2)
Pad thickness mm10.0
Clearance adjustmentAutomatic
Front brakes
Type4 opposed piston, ventilated disc
Disc effective dia.¢thickness mm263¢32
Wheel cylinder I.D. mm40.0 (¢2), 46.0 (¢2)
Pad thickness mm10.0
Clearance adjustmentAutomatic
Rear brakes
RS(standard)
TypeFloating caliper, 1 piston, ventilated disc
Disc effective dia.¢thickness mm237¢20
Wheel cylinder I.D. mm34.9
Pad thickness mm10.0
Clearance adjustmentAutomatic
Rear brakes
Type2 opposed piston, ventilated disc
Disc effective dia.¢thickness mm252¢22
Wheel cylinder I.D. mm40.0 (¢2)
Pad thickness mm9.0
Clearance adjustmentAutomatic
Brake fluidDOT3 or DOT4
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Page 1048 of 1449
BASIC BRAKE SYSTEM -Lubricants/Sealant/Special Tools35A-6
LUBRICANTS
ItemsSpecified LubricantQuantity
Brake fluidDOT3 or DOT4As required
Piston, wheel cylinder body
Piston boot, piston seal, shimRepair kit grease
Guide pin, lock pin, pin boot
Pad assembly
SEALANT
ItemsSpecified sealantRemarks
Fitting3M ATD Part No. 8661, 8663 or equivalentSemi-drying sealant
SPECIAL TOOLS
ToolNumberNameUse
MB991568Push rod adjusting
socketAdjustment of the brake booster push rod
protrusion amount
AMB990964
A: MB990520Brake tool setPushing-in of the disc brake piston
DDisc brake piston pushing-in
MB990998Front hub remover
and installerProvisional holding of the wheel bearing
Page 1051 of 1449
BASIC BRAKE SYSTEM -On-vehicle Service35A-9
CHECK VALVE OPERATION CHECK
1. Remove the vacuum hose. (Refer to P.35A-17.)
Caution
The check valve should not be disassembled from
the vacuum hose as they are united as one part.
2. Check the operation of the check valve by using a vacuum
pump.
Vacuum pump
connectionAccept/reject criteria
Connection at the brake
booster side (A)A negative pressure (vacuum) is
created and held.
Connection at the intake
manifold side (B)A negative pressure (vacuum) is
not created.
Caution
If the check valve is defective, always replace it as
an assembly unit together with the vacuum hose.
PROPORTIONING VALVE FUNCTION TEST
Caution
The proportioning valves are installed independently for
the right and left brake lines. Always measure each valve.
1. Connect two pressure gauges to the output port of the
master cylinder and output port of the proportioning valve.
2. Bleed the brake line and the pressure gauges. (Refer
to P.35A-10.)
3. Depress the brake pedal gradually. Then check that the
split point, where the output fluid pressure begins to drop
in proportion to the output fluid pressure, is at the standard
value.
Standard value: 2.70 - 3.19 MPa
4. Depress the brake pedal more strongly than at the above
step. Then check that the output fluid pressure is at the
standard value when the input fluid pressure is 6.86 MPa.
Standard value: 3.68 - 4.17 MPa
5. Measure each output fluid pressure at both valves, and
check that the difference between the two is at the limit
value or less.
Limit: 0.49 MPa
6. If the measured pressure exceeds the limit, replace the
proportioning valve.
ValveSpring
Booster
sideA
B
Intake
manifold
side
Pressure gauge (A)
Proportioning valve
Output port
Output port
Pressure gauge (B)
gauge (B)>
Input pressure
Output
pressureSplit point
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BASIC BRAKE SYSTEM -On-vehicle Service35A-10
BLEEDING
Caution
Specified brake fluid: DOT3 or DOT4
Always use the specified brake fluid. Avoid using a
mixture of the specified brake fluid and other fluid.
MASTER CYLINDER BLEEDING
The master cylinder used has no check valve, so if bleeding
is carried out by the following procedure, bleeding of air from
the brake pipeline will become easier. (When brake fluid is
not contained in the master cylinder.)
1. Fill the reserve tank with brake fluid.
2. Keep the brake pedal depressed.
3. Have another person cover the master cylinder outlet
with a finger.
4. With the outlet still closed, release the brake pedal.
5. Repeat steps 2 - 4 three or four times to fill the inside
of the master cylinder with brake fluid.
BREMBO DISC BRAKE BLEEDING
Caution
Take care not to contact the parts or tools to the caliper
because the paint of caliper will be scratched. And if
there is brake fluid on the caliper, wipe out quickly.
Connect a vinyl tube to the outer end of the air bleeder screw
to bleed the circuit of air. Then, connect the vinyl tube to
the inner end and bleed the circuit of air. Except for these,
the conventional procedures shall be followed. After the circuit
has been bled of air, tighten both air bleeder screws securely.
BRAKE PIPE LINE BLEEDING
Bleed the air in the sequence shown in the figure.
Air bleeder screw
( ): R.H. drive vehicles
4 (2)
1 (3)
2 (4)
3 (1)
( ): R.H. drive vehicles
4, 6 (1, 3)
2 (5)
1, 3 (4, 6)
5 (2)
Vehicles with ABS
Vehicles without ABS
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BASIC BRAKE SYSTEM -On-vehicle Service35A-11
BRAKE FLUID LEVEL SENSOR CHECK
The brake fluid level sensor is in good condition if there is
no continuity when the float surface is above “MIN” and if
there is continuity when the float surface is below “MIN”.
DISC BRAKE PAD CHECK AND REPLACEMENT
NOTE
The wear indicator contacts the brake disc when the brake
pad thickness reaches approximately 2 mm and emit a
squealing sound to warn the driver.
1. Check the brake pad thickness through the caliper body
check port.
Standard value: 10.0 mm
Limit: 2.0 mm
2. When the thickness is less than the limit, always replace
the pads at an axle set.
3. Remove the pin bolt. Pivot the caliper assembly and hold
it with wires.
Caution
Do not wipe off the special grease that is on the pin
or allow it to contaminate the pin.
4. Remove the following parts from the caliper support.
1. Pad and wear indicator assembly
2. Pad assembly
3. Clip
4. Outer shim
5. In order to measure the brake drag force after pad
installation, measure the rotary-sliding resistance of the
hub with the pads removed. (Refer to P.35A-21.)
6. Install the pads and caliper assembly, and then check
the brake drag force. (Refer to P.35A-21.)
14Z0017
Front Rear
Front Rear
Front Rear
12 34
3
1
2 3
4
3
Page 1054 of 1449
BASIC BRAKE SYSTEM -On-vehicle Service35A-12
Caution
Take care not to contact the parts or tools to the caliper
because the paint of caliper will be scratched. And if
there is brake fluid on the caliper, wipe out quickly.
NOTE
The wear indicator contacts the brake disc when the brake
pad thickness reaches approximately 2 mm and emit a
squealing sound to warn the driver.
1. Check the brake pad thickness through the caliper body
check port.
Standard value: 10.0 mm , 9.0 mm
Limit: 2.0 mm
2. When the thickness is less than the limit, always replace
the pads at an axle set.
(1) Holding the cross spring with one hand, pull the pin
out of the caliper.
(2) Remove the pad from the caliper.
(3) To measure brake drag force after new pads have
been installed, use a spring balance to measure the
turning sliding resistance of the hub with the pads
removed. (Refer to P.35A-21.)
(4) Clean the piston and, using the special tool, push
the piston into the cylinder.
Pads
Front Rear
Pads
MB990520
