1998 JAGUAR X308 brake

Hydraulic B
rake Actuation -
Lubri
cants, Fluids, Sealants and Adhesives
Torques
Torques - Brembo Brakes
Brake Tube, Hoses and Bracket Torques
CAUTI
ON: Replacement of
nuts and bolts: Various thread-locking devices are used on nuts and bolts throughout the
vehicle. These devices restrict the number of times a nut or bolt can be used. See section 100-00 for information.


UnitS
pecification
Brake flu

id
ITT Supe
r Dot 4
Com

ponent
Nm
N

ut - master cylinder to brake booster
21
-29
Nu

t - brake pedal pivot-pin to pedal housing
17
-23
Nu

t - brake switch to pedal housing
3
Nu

t - pedal housing to body
15
-20
Nu

t - brake booster to pedal housing
22
-28
Com

ponent
Nm
Bleed n

ipple
12
-16
U

nion bolt - brake hose to caliper
22
-26
Com

ponent
Nm
Bleed n

ipple - front
4-
6
Bleed n

ipple - rear
8-1
1
Hose to fr

ont caliper
10
-14
U

nion to rear caliper - union bolt
30
-40
M1

0 hose locknut
15
-20
M10

brake tube female-nut
13
-17
M10

brake tube male-nut
13
-17
M12

brake tube male-nut
15
-20
M18

brake tube male-nut
22
-28
Brake tube clip retention

-bracket to body
4-
6

Hydraulic Br
ake Actuation -
Hydraulic Brake Actuation
Description and Operation

The hydraulic brake system is split in to two independent circuits: the primary ci rcuit operates the front brakes and the
secondary circuit operates the re ar brakes. This type of system prevents comple te brake failure in the event of a brake tube
fracture.
The hydraulic brake system consists of the following components:

Ite
m
Descr
iption
1Pedal Housi

ng / Booster - refer to 206-07
2Vacu

um Hose - refer to 206-07
3Mast
er Cyl
inder / Reservoir
4Primary Brake Circu
i
t
5Secon
dary Brake Circuit
6Hydrauli c
Pump / Motor Unit - refer to 206-09
7ABS/Traction

Control Control Modu
le (ABS/TCCM) - refer to 206-09
8Hydraulic Cont
rol Unit (HCU) - refer to 206-09
6/
7/
8
Br
ak
e Control Modulator
9Brake
Di
sc - refer to 206-03 or 206-04
10Brake
Cali
per - refer to 206-03 or 206-04
11W
h
eel Speed Sensor - refer to 206-09
12ABS Warning Lamp -
refer to 206
-09
13Brake F
l
uid Level Warning-Lamp

The t
andem master cylinder contains two in
dependent pistons, fluid pressure to each brake circuit is controlled by its own
individual piston. Brake fluid is supplied to the master cylinder by the reservoir, which is divided into two sections to preve nt
total fluid loss should one of the circuits fail. A port situated at the bottom of each section of the reservoir supplies the f luid
to each piston.
The fluid reservoir has a fluid-le vel indicator switch installed, which operates when the fluid level is low, causing the brake
fluid level warning-lamp to illuminate.
Bra
ke Caliper
The brake
calipers are of the single piston
type. The caliper carrier, which is secured to the vertical link by two bolts, carr ies
the single-piston caliper housing. The cali per housing is secured to the caliper carrier by two guide-pins and an anti-rattle
spring. When the brakes are applied, the caliper-housing piston pushes the brake pad in front of it, to wards the brake disc.
This movement forces the calipe r housing to move along the guid e-pins, in the opposite direction of the piston, to apply the
second brake pad.
Br
embo Brake Caliper
The four
cylinder brake caliper is rigidly attached to the vert
ical link via an anchor bracket. The caliper is a split assembly
with each side of the caliper, housing two pistons. The two-pairs of opposed pistons act direct ly on the brake pads mounted
one each side of the disc.




Mast
er Cylinder and Reservoir

Hydraulic Br
ake Actuation
- Brake Fluid Reservoir
Remo
val and Installation
Remov
a
l
• C
A
UTIONS:
Replacement of nuts and bolts: Various thread-locking de vices are used on nuts and bolts throughout the vehicle.
These devices restrict the number of times a nut or bolt can be used. See section 100-00 for information.
Remove brake fluid spilla ge immediately from paint work, with clean water.
1. Position vehicl
e on a four-post lift.
2. Open engine compartment and fit paint work protection covers
to fenders.
3. Disconnect battery ground cable (IMPORTANT, see operation
86.15.19 for further information).
4. Remove engine compartment rear cover. Refer to operation
76.11.35.
5. Remove pedal housing, brake booster and master cylinder
assembly. Refer to operation 70.35.39.
6. Remove reservoir filler cap and empty residual brake fluid into
a container. Refit cap.

7. Re
move fluid reservoir from master cylinder.
R
e
move locating pin.
Pull reservoir

from master cylinder.

8. Install plugs into f
luid reservoir ports.
9. Remove and discard seal s from master cylinder.

I
nstallation


10
.
Install plugs into master cylinder ports.
11. Clean components and mating surfaces.

1. Inst
all seals into master cylinder.
Re

move plugs.
Lubricate seals with
cl
ean brake fluid.
Inst

all seals.

2. Install
reservoir to master cylinder.
Re

move plugs.
Install

reservoir, making sure
reservoir is fully seated.
Inst
all locating pin.
3. Install pedal housing, brake booster and master cylinder
assembly. Refer to operation 70.35.39.
4. Install engine compartment rear cover. Refer to operation
76.11.35.
5. Reconnect battery ground cable (IMPORTANT, see operation

8
6
.15.15 for further information).
6. Bleed brake system. Refer to operation 70.25.03.
7. Remove paint-work protection covers and close engine
compartment.

Hydraulic B
rake Actuation
- Brake Master Cylinder
Re
moval and Installation
Remov

al
• C
AUTIONS:
Replacement of nuts and bolts: Various thread-locking de vices are used on nuts and bolts throughout the vehicle.
These devices restrict the number of times a nut or bolt can be used. See section 100-00 for information.
Remove brake fluid spilla ge immediately from paint work, with clean water.
1. Position vehi
cle on a four-post lift.
2. Open engine compartment and fit paint work protection covers
to fenders.
3. Disconnect battery ground cable (IMPORTANT, refer to
operation 86.15.19 for fu rther information).
4. Remove engine compartment rear cover. Refer to operation
76.11.35.
5. Remove pedal housing, brake booster and master cylinder
assembly. Refer to operation 70.35.39.
6. Place assembly on a work bench.

7. R
emove nuts securing master cylinder to brake booster.

8. R
emove master cylinder from brake booster.
Re

move master cylinder.
Remove an

d discard seal.
9. Remove filler cap and empty residual brake fluid into a
container. Fit cap.
10. Remove fluid reservoir from master cylinder.
R
emove locating pin.
Pull

reservoir from master cylinder.

Lubricate seals with cl
ean brake fluid.
Inst

all seals.

2. Install
fluid reservoir to master cylinder.
R

emove plugs from reservoir
Install

reservoir, making sure
reservoir is fully seated.
Inst
all locating pin.

3. Inst
all master cylinder to brake booster.
Inst

all seal.
Inst

all master cylinder, make sure master cylinder rod
locates brake booster rod.

4. Inst
all and tighten nuts to 21-29 Nm.
5. Install pedal housing, brake booster and master cylinder
assembly. Refer to operation 70.35.39.
6. Install engine compartment rear cover. Refer to operation
76.11.35.
7. Connect battery ground cable (IMPORTANT, see operation
86.15.15 for further information).
8. Bleed brake system. Refer to operation 70.25.03.
9. Remove paint-work protection covers and close engine


com

partment.