Isuzu Trooper (1998-2002 year). Manual - part 217

5C – 20 POWER ASSISTED BRAKE SYSTEM

Front and Rear Brakes

N·m (kg·m/lb·ft)

74(7.5/54)

Front disc brake

Rear disc brake

35(3.6/26)

74(7.5/54)

155(15.8/115)

35(3.6/26)

104(10.6/77)

44(4.5/32)

8(0.8/69 Ib

･in)

8(0.8/69 Ib

･in)

POWER ASSISTED BRAKE SYSTEM  5C – 21

SPECIAL TOOLS

ILLUSTRATION

PART NO.

PARTNAME

Primary piston holder

5-8840-2306-0

(including master cylinder attach-

(J-39242)

ment and master cylinder plug)

5-8840-0277-0

Radiator cap tester

(J-24460-01)

5-8840-2300-0

Push rod gauge

(J-39216)

5-8840-0279-0

Vacuum pump

(J-23738-A)

5-8840-2305-0

Push rod support

(J-39241)

5C – 22 POWER ASSISTED BRAKE SYSTEM

GENERAL DESCRIPTION

MASTER CYLINDER

The master cylinder contains two pistons that supply
the hydraulic pressure for a dual-circuit braking
system. The primary piston provides the fluid
pressure to the front brakes, while the secondary
piston provides the fluid pressure to the rear brakes.
If the pressure is lost from either system, the
remaining system will function to stop the vehicle.

CAUTION:
1) The master cylinder is not repairable. If found

defective, it must be replaced as complete
assembly.

2) If any hydraulic component is removed or

disconneted, it may be necessary to bleed all or
part of the brake system.

3) The torque values specified are for dry,

unlubricated fasteners.

4) Perform service operations on a clean bench free

from all mineral oil materials.

330RW013

POWER ASSISTED BRAKE SYSTEM  5C – 23

VACUUM BOOSTER

This booster is a tandem vacuum unit with a diaphragm effective diameter 205 mm + 230 mm (gasoline
engine model) / 180 mm + 205 mm (diesel engine model).  In normal operating mode, with the service
brakes in the released position, the tandem vacuum booster operates with vacuum on both sides of its
diaphragms.  When the brakes are applied, air at atmospheric pressure is admitted to one side of each
diaphragm to provide the power assist.  When the service brake is released, the atmospheric air is shut
off from the one side of each diaphragm.  The air is then drawn from the booster through the vacuum
check valve to the vacuum source.

CAUTION:
1) If any hydraulic component is removed or disconnected, it may be necessary to bleed all or part of

the brake system.

2) The torque values specified are for dry, unlubricated fasteners.
3) The vacuum booster is not repairable and must be replaced as complete assembly.