1995 ISUZU TROOPER Workshop Manual

l·u·IINSTALLATION
5. Vacuum booster
I~EI Vacuum booster push rod adjustment
NOTE:
When replacing either master cylinder or vacuum
booster, be sure
to measure push rod, and adjust if
required.
~ Push rod gauge : J-39216
~ Vacuum pump : J-23738-A
Push rod
support: J-39241
• Remove retainer from vacuum booster front
shell using a small screwdriver. Then gently
draw plate and seal assembly out of the shell
inside (Fig. 5A1-4).
Fig.
5A1-4
• Set push rod gauge on vacuum booster, and
apply negative pressure by means of vacuum
pump so that the pressure in the vacuum
booster becomes
500 mm Hg. (Fig. 5A1-5).
NOTE:
Be sure to apply NEGATIVE pressure after
installing a push rod gauge on vacuum booster.
J-39216
Fig. 5A1-5
BRAKE BOOSTER SYSTEM 5A1-3
Fig. 5A1-6
• Measure dimension (b) (Fig. 5A 1-6)
~~~ Dimension (b) (Standard) mm I 0 ± 0.1
• If dimension (b) is out of the standard range,
adjust push rod using the
special tool (Fig. 5A 1-
7).
T·wrench
J-39241
Fig. 5A1-7
• Mount plate and seal assembly in vacuum
booster
front shell. Then install retainer.
4. Vacuum booster fixing nut
I~I ____ T_o_rq_u_e _______ N_·m __ (l_b·_ft_) __ ~_2_1_(_16_)_
3. Yoke clevis
2. Vacuum hose
• Make sure that the arrow on the hose points in
the direction
of the engine.
1.
Master cylinder
• Refer to "Master Cylinder Installation" in
Section 5A.

SA 1-4 EXTERI _ BRAKE BOOSTER SYSTEM OR COMPQ .• N,.=E~N~T_s ____ _
l;JJ!!
3 4 5 6 7
8 9
Removal steps. d
1 Master cylm er
2. Vacuum b.ooster
3. Yoke
clevis
4
: Lock n.ut .
5
Retainmg clip d
6: Valve body guar
7. Silencer
8. filter d spacer
9. 2 gas.kets an
10.
Retame~ seal assembly 11. Plate an
Installation s:~P.; the removal To install, fo o rse order. ·In the reve
steps
DREMOVAL
-----------FF:iigg. SA1-8-
1::1 1 • in
Section 1. Master cyl!.~::ter Cylinder Remova • Refer to
SA. t r I" in this
2 Vacuu "Vacuum m boos e Booster Remova · • Refer to
section.
Yoke
clevis 3. t Lock nu .
4. Retaining clop d
5. Valve body guar 6.
Silencer 7.
a. Filter d spacer
9 2 gaskets an tthe retainer.
1 0. Retainer a II screwdriver tol'::'a~~ssembly from • Use a sm II outthe plate an s Gently pu F' SA 1-9). the shell ( IQ.
11. Fig.
SA1-9
I assembly Plate and sea
•

[1!) INSPECTION AND REPAIR
Visual check:
'-"' Make necessary parts replacement if cuts, nicks,
excessive wear,
or other abnormal conditions are
found through inspection.
Check the following parts.
• Yoke clevis
• Valve
body guard
• Silencer
• Filter
• Plate
and seal assembly.
I••IINSTALLATION
11. Plate and seal assembly
1 0. Retainer
9. 2 gaskets and spacer
8. Filter
7. Silencer
6. Valve body guard
5. Retainer
4. Lock nut
20 (15) 1~1 Torque N·m (lb·ft) ----------1....---
3. Yoke clevis
2. Vacuum booster
• Refer to "Vacuum Booster Installation" in this
section.
'-"" 1. Master cylinder
• Refer to "Master Cylinder Installation" in
Section 5A.
• After installation, perform brake pedal check
and adjustment. Refer
to "Brake Pedal
Assembly" in Section 5A.
BRAKE BOOSTER SYSTEM 5A 1-5

5A 1-6 BRAKE BOOSTER SYSTEM
UNIT REPAIR
VACUUM BOOSTER
• The vacuum booster cannot be disassembled
for repair. Replace a defective vacuum booster
with a new one.
MAIN DATA AND SPECIFICATIONS
GENERAL SPECIFICATIONS
Vacuum booster diaphragm diameter
Front
Rear
Push rod stroke
Plunger diameter
Push rod diameter
TORQUE SPECIFICATIONS
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
13 (1131b·in)
Fig. 5A1-10
205 (8.07)
230 (9.06)
More than 32.0 (1.26)
10.25 (0.40)
27.4 (1.08)
N·m (lb·ft)
.............................................. ----------------------------------~ .

BRAKE BOOSTER SYSTEM 5A 1-7
SPECIAL TOOLS
ILLUSTRATION TOOL NO.
TOOL
NAME
0
J-39216
Push rod gauge
~
J-23738-A
Vacuum pump
r
J-39241
Push rod support

MEMO
•

DISC BRAKES 5A2-1
SECTION 5A2
DISC BRAKES
w CAUTION:
All brake attaching fasteners are an important attaching part in that they could affect performance of vital
parts and systems, and/or could result in major repair expense. They must be replaced with one of the same
part
number or with an equivalent part if replacement becomes necessary. Do not use replacement parts of
lesser quality or substitute design. Torque values must be used as specified during reassembly to assure
proper retention of these parts.
CONTENTS
General Description . . . . . . . . . . . . . . . . . . . . 5A2-1
Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5A2-1
Diagnosis
..................... See Section SA
On-Vehicle Service . . . . . . . . . . . . . . . . . . . . 5A2-2
Front Disc Brakes . . . . . . . . . . . . . . . . . . . . 5A2-2
Brake Pads
Inspection . .

. . . . . . . . . . . . 5A2-2
Brake Pads Replacement . . . . . . . . . . . 5A2-3
Servicing
the Rotor . . . . . . . . . . . . . . . . 5A2-4
Caliper Replacement . .

. . . . . . . . . . . . . 5A2-6
Rebuilding
the Caliper . . . . . . . . . . . . . 5A2-8 Rear
Disc Brakes .................... 5A2-1 0
Brake
Pads Inspection ............. 5A2-1 0
Brake Pads Replacement ........... 5A2-1 0
Servicing the Rotor ............... 5A2-12
Caliper Replacement .............. 5A2-14
Rebuilding the
Caliper ............. 5A2-17
Parking Brakes . . . . . . . . . . . . . . . .
See Section SC
Main Data and Specifications ........... 5A2-19
General Specifications ............... 5A2-19
Torque Specifications
............... 5A2-19
GENERAL DESCRIPTION
The disc brake assembly consists of a caliper, piston,
rotor, pad assembly and
support bracket. The caliper
assembly has a single bore and is mounted to the
support bracket with 2 mounting bolts. The support
bracket allows the caliper to move laterally against the
rotor. The
caliper is a one-piece casting with the
inboard side containing the piston bore. A square cut
rubber
seal is located in a groove in the piston bore
which provides the hydraulic seal between the piston
and the cylinder
wall.
NOTE:
• Replace all components included in repair kits
used
to service this caliper.
• Lubricate rubber parts with clean brake fluid to
ease assembly.
• If any hydraulic component is removed or
disconnected, it may be necessary to bleed all or
part of the brake system.
• Replace pads in axle sets only.
•
The torque values specified are for dry,
unlubricated fasteners.
• Perform service operation a clean bench free
from all mineral oil materials.
OPERATION
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 move (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.