Chrysler PT Cruiser. Manual - part 422

Both brand master cylinders offer two master cyl-

inders depending on whether or not the vehicle is
equipped with antilock brakes (ABS). Vehicles with-
out ABS use a standard compensating-port master
cylinder, while vehicles equipped with ABS use a cen-
ter-valve design master cylinder. The bore diameter
for all applications using a Bosch master cylinder is
23.82 mm (0.937 in.). The bore diameter for all appli-
cations using a Continental Teves master cylinder is
22.2 mm (0.874 in.).

All non-ABS master cylinders are a four-outlet

design (one for each wheel brake). There are two
ports at each piston. One feeds a front wheel brake
while the other feeds the opposite side rear wheel
brake. The rear wheel brake ports are drilled and
threaded to accept screw-in proportioning valves (Fig.
80). One valve is threaded into the bottom of the
master cylinder housing at the primary piston and
the other is threaded into the right side of the mas-
ter cylinder housing at the secondary piston.

All ABS master cylinders are a two-outlet design

and the brake tubes from these primary and second-
ary outlet ports lead directly to the integrated control
unit (ICU) before going to each wheel brake (Fig. 76).

All master cylinders mount to the power brake

booster in the same manner.

The master cylinder body is an anodized aluminum

casting. It has a machined bore to accept the master
cylinder pistons and also has threaded ports with
seats for hydraulic brake tube connections.

The master cylinder has the brake fluid reservoir

mounted on top of it which gravity feeds brake fluid
to the master cylinder when it is required. The res-
ervoir is made of see-through plastic and it houses
the brake fluid level switch. A removable brake fluid
level switch is mounted in the left side.

OPERATION

When the brake pedal is pressed, the master cylin-

der primary and secondary pistons apply brake pres-
sure through the proportioning valves (on non-ABS
vehicles) and chassis brake tubes to each brake
assembly. The brake fluid reservoir supplies the
brake hydraulic system with the necessary fluid to
operate properly.

The non-ABS master cylinder’s primary outlet

ports supply hydraulic pressure to the right front
and left rear brakes while the secondary outlet ports
supply hydraulic pressure to the left front and right
rear brakes. ABS equipped master cylinder outlet
ports supply hydraulic pressure to the ABS Inte-
grated Control Unit (ICU) where it is distributed to
the individual wheel brakes.

The master cylinder reservoir cap diaphragm is slit

to allow atmospheric pressure to equalize on both
sides of the diaphragm.

STANDARD PROCEDURE - MASTER CYLINDER
BLEEDING

(1) Clamp the master cylinder in a vise.

NOTE: Depending on master cylinder type (Bosch
or Continental Teves, with or without ABS) refer to
steps 2 - 5 for proper Bleeder Tube installation.

NOTE: On vehicles without ABS this procedure is
designed to be performed with the proportioning
valves installed in the master cylinder.

(2) Bosch Master Cylinder without ABS – Attach

four Bleeder Tubes, Special Tool 8358-1, to the four
ports of the master cylinder (proportion valves
installed) and tighten to 17 N·m (145 in. lbs.) torque
(Fig. 70). Flex the Bleeder Tubes and position the
open ends into the master cylinder reservoir so their
outlets are below the surface of the brake fluid in the
reservoir when filled.

(3) Bosch Master Cylinder with ABS – Attach a

Bleeder Tube, Special Tool 8358-1, to the primary
port of the master cylinder and tighten to 17 N·m
(145 in. lbs.) torque (Fig. 71). Attach a Bleeder Tube,
Special Tool 8358-2, to the secondary port of the mas-
ter cylinder and tighten to 17 N·m (145 in. lbs.)
torque. Flex the Bleeder Tubes and position the open
ends of the tubes into the master cylinder reservoir
so their outlets are below the surface of the brake
fluid in the reservoir when filled.

Fig. 70 Bleeding Master Cylinder - W/O ABS

1 - WOODEN DOWEL
2 - MASTER CYLINDER

5 - 40

BRAKES - BASE

MASTER CYLINDER (Continued)

NOTE: Continental Teves Master Cylinder without
ABS – In the following step the last substep states
to submerge the ends of the Bleeder Tubes in a jar
filled with brake fluid instead of the master cylinder
reservoir. That is because all four Bleeder Tubes
will not fit through the slot at the base of the reser-
voir neck (Fig. 72), sufficiently below the fluid level.

(4) Continental Teves Master Cylinder without

ABS – Attach the special tools for bleeding the mas-
ter cylinder in the following fashion (Fig. 73):

(a) Thread Adapter, Special Tool 8822-1, into the

primary outlet port of the master cylinder without
a proportioning valve. Tighten Adapter to 17 N·m
(145 in. lbs.) torque.

(b) Thread Adapter, Special Tool 8822-2, into the

secondary outlet port of the master cylinder with-
out a proportioning valve. Tighten Adapter to 17
N·m (145 in. lbs.) torque.

into each Adapter. Tighten Tube nuts to 17 N·m
(145 in. lbs.) torque.

(d) Thread a Bleeder Tube, Special Tool 8358-2,

into each proportioning valve. Tighten Tube nuts to
17 N·m (145 in. lbs.) torque.

(e) Flex and place the open ends of the Bleeder

Tubes into a clear jar containing enough fresh
brake fluid to submerge the ends on the Bleeder
Tubes. Do not completely fill the jar with fluid or
fluid being bled from master cylinder will overflow
jar.

(5) Continental Teves Master Cylinder with ABS –

Attach the special tools for bleeding the master cyl-
inder in the following fashion (Fig. 74):

(a) Thread Adapter, Special Tool 8822-1, into the

primary outlet port of the master cylinder. Tighten
Adapter to 17 N·m (145 in. lbs.) torque.

(b) Thread Adapter, Special Tool 8822-2, into the

secondary outlet port of the master cylinder.
Tighten Adapter to 17 N·m (145 in. lbs.) torque.

into each Adapter. Tighten Tube nuts to 17 N·m
(145 in. lbs.) torque.

(d) Flex each Bleeder Tube and place open end

into the neck of the master cylinder reservoir,

Fig. 71 Bleeding Master Cylinder - W/ABS

1 - WOODEN DOWEL
2 - MASTER CYLINDER

Fig. 72 Master Cylinder Reservoir Neck

1 - RESERVOIR NECK
2 - SLOT

Fig. 73 Bleeding Master Cylinder - Without ABS

1 - WOODEN DOWEL
2 - ADAPTER 8822-1
3 - TUBE 8358-1
4 - ADAPTER 8822-2
5 - PROPORTIONING VALVE
6 - TUBE 8358-2

BRAKES - BASE

5 - 41

MASTER CYLINDER (Continued)

down through the slot at the base of the neck (Fig.
72). Position the open ends of the tubes into the
reservoir so their outlets are below the surface of
the brake fluid in the reservoir when filled.

NOTE: Make sure ends of the Bleeder Tubes stay
below the surface of the brake fluid in reservoir at
all times during the bleeding procedure.

(6) Fill the brake fluid reservoir with fresh Mopar

Brake Fluid DOT 3 Motor Vehicle, or equivalent.
(Refer to 5 - BRAKES/HYDRAULIC/MECHANICAL/
FLUID - SPECIFICATIONS)

(7) Using an appropriately sized wooden dowel as

a pushrod (Fig. 70) (Fig. 71) (Fig. 73) (Fig. 74), slowly
press the pistons inward discharging brake fluid
through the Bleeder Tubes, then release the pres-
sure, allowing the pistons to return to the released
position. Repeat this several times until all air bub-
bles are expelled from the master cylinder bore and
Bleeder Tubes.

(8) Remove the Bleed Tubes and Adapters from the

master cylinder and plug the master cylinder outlet
ports.

(9) Install the fill cap on the reservoir.
(10) Remove the master cylinder from the vise.
(11) Install the master cylinder on the vehicle.

(Refer to 5 - BRAKES/HYDRAULIC/MECHANICAL/
MASTER CYLINDER - INSTALLATION)

REMOVAL

REMOVAL - LHD WITH ABS

NOTE: Before proceeding, (Refer to 5 - BRAKES -
WARNING) (Refer to 5 - BRAKES - CAUTION).

CAUTION: The vacuum in the power brake booster
must be pumped down before removing the master
cylinder to prevent the booster from sucking in any
contamination. This can be done by pumping the
brake pedal while the engine is not running until a
firm brake pedal is achieved.

(1) With the engine not running, pump the brake

pedal 4-5 strokes until the pedal feel is firm.

(2) Unclip the air cleaner cover (two clips) and

move the cover aside.

(3) Remove the air cleaner housing by pulling

straight up.

(4) Disconnect the negative (ground) cable from

the battery and isolate the cable.

(5) Unlatch the power distribution center, lift it

up, and move it to the side.

(6) Remove the vehicle wiring harness connector

from brake fluid level switch in master cylinder
brake fluid reservoir (Fig. 75).

Fig. 74 Bleeding Master Cylinder - With ABS

1 - WOODEN DOWEL
2 - TUBE 8358-1
3 - ADAPTER 8822-2
4 - ADAPTER 8822-1

Fig. 75 Master Cylinder

1 - POWER BRAKE BOOSTER
2 - BRAKE FLUID LEVEL SWITCH
3 - MASTER CYLINDER

5 - 42

BRAKES - BASE

MASTER CYLINDER (Continued)

(7) Disconnect the primary and secondary brake

tubes at the master cylinder outlet ports (Fig. 76).
Install plugs at all of the open brake tube outlets on
the master cylinder.

(8) Continental Teves Master Cylinder Only – If

equipped with a manual transaxle, remove the clamp
and slide the clutch actuator hose off the reservoir
port (Fig. 77).

(9) Clean the area around where the master cylin-

der attaches to the power brake booster using a suit-
able brake cleaner such as Mopar

t Brake Parts

Cleaner or an equivalent.

(10) Remove the two nuts attaching the master

cylinder to the power brake booster (Fig. 78).

(11) Slide the master cylinder straight out of the

power brake booster.

REMOVAL - LHD WITHOUT ABS

NOTE: Before proceeding, (Refer to 5 - BRAKES -
WARNING) (Refer to 5 - BRAKES - CAUTION).

(1) With the engine not running, pump the brake

pedal 4-5 strokes until the pedal feel is firm.

(2) Unclip the air cleaner cover (two clips) and

move the cover aside.

(3) Remove the air cleaner housing by pulling

straight up.

(4) Disconnect the negative (ground) cable from

the battery and isolate the cable.

(5) Unlatch the power distribution center, lift it

up, and move it to the side.

Fig. 76 Primary And Secondary Brake Tubes To ICU

1 - MASTER CYLINDER
2 - HCU
3 - LEFT FRONT CHASSIS BRAKE TUBE
4 - SECONDARY BRAKE TUBE
5 - PRIMARY BRAKE TUBE

Fig. 77 Clutch Actuator Hose At Master Cylinder

1 - RESERVOIR
2 - HOSE CLAMP
3 - CLUTCH ACTUATOR HOSE

Fig. 78 Master Cylinder Mounting Nuts

1 - MASTER CYLINDER
2 - POWER BRAKE BOOSTER
3 - MOUNTING NUTS

BRAKES - BASE

5 - 43

MASTER CYLINDER (Continued)

Content .. 420 421 422 423 ..