brake pads FORD SIERRA 1987 2.G Braking System Workshop Manual

System type
Conventional braking system (except P100 models) . . . . . . . . . . . . . . . Front discs and rear drums with vacuum servo assistance, dual
hydraulic circuit split front/rear, deceleration sensitive pressure relief
valve in rear hydraulic circuit. Cable-operated handbrake on rear
wheels.
ABS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Front and rear discs operated via electrically-driven hydraulic pump,
dual hydraulic circuit split front/rear, pressure regulating valve in rear
hydraulic circuit. Cable-operated handbrake on rear wheels
P100 models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Front discs and rear drums with vacuum servo assistance, dual
hydraulic circuit split front/rear, load apportioning valve in rear
hydraulic circuit. Cable-operated handbrake on rear wheels
Front discs
Type:
1.3 and 1.6 litre models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Solid
1.8 and 2.0 litre models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ventilated
Diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 240.0 mm (9.46 in)
Maximum disc run-out . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.15 mm (0.006 in)
Minimum pad friction material thickness . . . . . . . . . . . . . . . . . . . . . . . . 1.5 mm (0.06 in)
Rear discs
Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Solid
Diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 252.7 mm (9.96 in)
Maximum disc run-out . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.15 mm (0.006 in)
Minimum pad friction material thickness . . . . . . . . . . . . . . . . . . . . . . . . 1.5 mm (0.06 in)
Rear drums
Internal diameter:
1.3 and 1.6 litre Saloon and Hatchback models . . . . . . . . . . . . . . . . . 203.2 mm (8.0 in)
1.8 and 2.0 litre Saloon and Hatchback models and all Estate models .228.6 mm (9.0 in)
P100 models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 256.0 mm (10.1 in)
Minimum shoe friction material thickness . . . . . . . . . . . . . . . . . . . . . . . 1.0 mm (0.04 in)
Chapter 10
Braking system
Brake disc - examination, removal and refitting . . . . . . . . . . . . . . . . . .8
Brake drum - inspection and renewal . . . . . . . . . . . . . . . . . . . . . . . . .9
Brake fluid pipes and hoses - removal and refitting . . . . . . . . . . . . . .26
Brake hydraulic system (ABS) - bleeding . . . . . . . . . . . . . . . . . . . . . . .3
Brake hydraulic system (conventional braking system) - bleeding . . .2
Brake pedal - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . .30
Computer module (ABS) - removal and refitting . . . . . . . . . . . . . . . .21
Deceleration sensitive valve (Saloon, Hatchback and Estate models
with conventional braking system) - removal and refitting . . . . . . .23
Disc pads - inspection and renewal . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Fluid reservoir (ABS) - removal and refitting . . . . . . . . . . . . . . . . . . . .15
Front disc caliper - removal, overhaul and refitting . . . . . . . . . . . . . . .6
General information and precautions . . . . . . . . . . . . . . . . . . . . . . . . . .1
Handbrake cable - adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
Handbrake cable - removal and refitting . . . . . . . . . . . . . . . . . . . . . .27
Handbrake lever - removal and refitting . . . . . . . . . . . . . . . . . . . . . . .29Hydraulic unit (ABS) - removal and refitting . . . . . . . . . . . . . . . . . . . .16
Hydraulic unit accumulator (ABS) - removal and refitting . . . . . . . . .17
Hydraulic unit pressure switch (ABS) - removal and refitting . . . . . . .19
Hydraulic unit pump and motor (ABS) - removal and refitting . . . . . .18
Load apportioning valve (P100 models) - adjustment . . . . . . . . . . . .25
Load apportioning valve (P100 models) - removal and refitting . . . . .24
Master cylinder (conventional braking system) - removal, overhaul and
refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Rear brake backplate (drum brakes) - removal and refitting . . . . . . .11
Rear drum brake shoes - inspection and renewal . . . . . . . . . . . . . . . .5
Rear disc caliper - removal overhaul and refitting . . . . . . . . . . . . . . . .7
Rear disc splash shield - removal and refitting . . . . . . . . . . . . . . . . .12
Rear wheel cylinder (drum brakes) - removal, overhaul and refitting .10
Vacuum servo (conventional braking system) - removal and refitting .14
Valve block (ABS) - removal and refitting . . . . . . . . . . . . . . . . . . . . . .20
Wheel sensor (ABS) - removal and refitting . . . . . . . . . . . . . . . . . . . .22
10•1
Specifications Contents
10
Easy,suitable for
novice with little
experienceFairly easy,suitable
for beginner with
some experienceFairly difficult,
suitable for competent
DIY mechanic
Difficult,suitable for
experienced DIY
mechanicVery difficult,
suitable for expert
DIY or professional
Degrees of difficulty

8Open the bleed screw half a turn and have
your assistant depress the brake pedal slowly
to the floor and then, after the bleed screw is
retightened, quickly remove his foot to allow
the pedal to return unimpeded. Repeat the
procedure.
9Observe the submerged end of the tube in
the jar. When air bubbles cease to appear,
tighten the bleed screw when the pedal is
being held fully down by your assistant.
10Top-up the fluid reservoir. It must be kept
topped up throughout the bleeding
operations. If the connecting holes to the
master cylinder are exposed at any time due
to low fluid level, then air will be drawn into
the system and work will have to start all over
again.
11Assuming that the complete system is
being bled, the procedure described in the
preceding paragraphs should be repeated on
the front right-hand caliper followed by the
rear right-hand and left-hand wheel cylinders.
12On completion, remove the bleed tube,
and discard the fluid which has been bled
from the system unless it is required for bleed
jar purposes. Never re-use old fluid.
13On completion of bleeding, top-up the
fluid level in the reservoir. Check the action of
the brake pedal, which should be firm and free
from any “sponginess” which would indicate
that air is still present in the system.
With one-way valve
14There are a number of one-man brake
bleeding kits currently available from motor
accessory shops. It is recommended that one
of these kits should be used whenever
possible, as they greatly simplify the bleeding
operation and also reduce the risk of expelled
air or fluid being drawn back into the system.
15Proceed as described in paragraphs 5
and 6.
16Open the bleed screw half a turn then
depress the brake pedal to the floor and
slowly release it. The one-way valve in the
bleeder device will prevent expelled air from
returning to the system at the completion of
each stroke. Repeat this operation until clear
hydraulic fluid, free from air bubbles, can be
seen coming through the tube. Tighten the
bleed screw.
17Proceed as shown in paragraphs 11 to 13.
With pressure bleeding kit
18These too are available from motor
accessory shops and are usually operated by
air pressure from the spare tyre.
19By connecting a pressurised container to
the master cylinder fluid reservoir, bleeding is
then carried out by simply opening each bleed
screw in turn and allowing the fluid to run out,
rather like turning on a tap, until no air bubbles
are visible in the fluid being expelled.
20Using this system, the large reserve of
fluid provides a safeguard against air being
drawn into the master cylinder during the
bleeding operations.21This method is particularly effective when
bleeding “difficult” systems or when bleeding
the entire system at time of routine fluid
renewal.
22Begin bleeding with reference to
paragraphs 5 and 6 and proceed as described
in paragraphs 11 to 13.
1Keep the fluid reservoir replenished
throughout the bleeding operations.
2Remove the dust cap where fitted, and
clean around the bleed screw on the left-hand
front caliper. Fit a bleed tube to the screw and
immerse the open end in a jar containing
clean hydraulic fluid.
3Open the bleed valve one full turn and have
an assistant depress the brake pedal fully and
hold it down.
4Close the bleed valve and release the brake
pedal. Repeat the procedure until fluid ejected
from the end of the tube is free from air
bubbles.
5Repeat the operations on the right-hand
front caliper.
6Fit the bleed tube to the left-hand rear
caliper and open the bleed valve one full turn.
7Have an assistant depress the brake pedal
fully and hold it down.
8Switch on the ignition to position ll.
9Allow the fluid to bleed from the tube for at
least 15 seconds, when the fluid should be
free from air bubbles.
10Close the bleed valve.
11Release the brake pedal and wait for the
hydraulic pump to stop.
12Fit the bleed tube to the right-hand rear
caliper and open the bleed valve one full turn.
13Have your assistant depress the brake
pedal through half its travel and hold it there.
Allow the fluid to bleed from the tube for at
least 15 seconds, when the fluid should be
free from air bubbles.
14Close the bleed valve.
15Release the brake pedal and wait for the
hydraulic pump to stop then switch off the
ignition.
16Top-up the reservoir with clean fluid.
17When the hydraulic system is being bled
for the purpose of renewing the fluid at the
specified interval, as each caliper is bled,
operate the brake pedal continuously until
clean fluid is seen to enter the jar.
18When the hydraulic pump is running its
note will be heard to change once fluid has
purged through it. Do not allow the pump torun continuously for more than two minutes. If
it does run for a longer period, switch off the
ignition and allow the motor to cool for ten
minutes.
19On completion, discard the fluid which
has been bled from the system unless it is
required for bleed jar purposes. Never re-use
old fluid.
20Check the action of the brake pedal,
which should be firm and free from any
“sponginess”, which would indicate that air is
still present in the system.
Front disc pads
1The disc pad friction material can be
inspected for wear without removing the
roadwheels. Working beneath the vehicle,
insert a mirror between the caliper and the
roadwheel and check that the friction material
thickness is not less than the minimum given
in the Specifications.
2If any one of the pads has worn below the
specified limit, the front pads must be
renewed as an axle set (4 pads).
3To renew the pads, slacken the front
roadwheel nuts, apply the handbrake, then
jack up the front of the vehicle and support on
axle stands (see “Jacking and Vehicle
Support”). Remove the roadwheels. On P100
models, mark the position of the roadwheels
in relation to the wheel studs before removal.
4Proceed as follows according to model:
Girling caliper (1.3 and early 1.6 litre
models)
5Where applicable, disconnect the wiring to
the disc pad wear sensor.
6Unscrew and remove the bolt from the
upper caliper guide pin while holding the pin
stationary with a spanner (see illustration).
7Swing the caliper downwards and lift out
the disc pads. If the outboard pad is stuck to
4Disc pads -inspectionand
renewal
3Brake hydraulic system (ABS)
- bleeding
Braking system 10•3
10
4.6 Unscrewing the bolt from the upper
caliper guide pin - Girling caliper
Caution: Refer to the
precautions in Section 1.
Caution: The rear brake
hydraulic circuit may be under
considerable pressure, take
care not to allow hydraulic fluid
to spray into the face or eyes. Refer to the
precautions in Section 1.

the caliper, free it using a screwdriver with the
guide pin bolt fitted, as shown (see
illustration). Do not use a screwdriver to free
the inboard pad, as this may damage the
piston dust seal. The inboard pad can be
freed by hand after lowering the caliper.
8Brush all dust and dirt from the caliper,
pads and disc, but do not inhale it as it may
be injurious to health. Scrape any corrosion
from the disc.
9As the new pads will be thicker than the old
ones, the piston must be pushed squarely into
its bore to accommodate the new thicker
pads. Depressing the piston will cause the
fluid level in the reservoir to rise so to avoid
spillage, syphon out some fluid using an old
hydrometer or a teat pipette. Do not lever
between the piston and disc to depress the
piston ideally a spreader tool, applying equal
force to both sides of the caliper, should be
used (see illustration).
10Further refitting is a reversal of removal
bearing in mind the following points.
11If disc pads with wear sensors are fitted,
the pad with the sensor wire should be fitted
inboard.
12Ensure that the anti-rattle clips are
correctly located on the caliper.
13Repeat the procedure on the opposite
front brake.
14On completion, apply the footbrake hard
several times to settle the pads, then check
and if necessary top-up the fluid level in the
reservoir. 15Avoid heavy braking, if possible, for the
first hundred miles or so after fitting new
pads. This will allow the pads to bed in and
reach full efficiency.
Teves caliper (Later 1.6, 1.8 and 2.0
litre models)
16Prise the retaining clip from the caliper.
Hold it with a pair of pliers to avoid it causing
personal injury.
17Unclip the pad wear sensor from the
caliper, and disconnect the wiring plug (see
illustration).
18Using a 7 mm Allen key, unscrew and
remove the two guide bolts securing the
caliper to the carrier bracket, and withdraw
the caliper (see illustration). Support the
caliper on an axle stand to avoid straining the
hydraulic hose.19Withdraw the disc pads from the caliper
(see illustration). It may be necessary to prise
the outboard pad with a screwdriver to
release it from the caliper. Do not use a
screwdriver to free the inboard pad, as this
may damage the piston dust seal.
20Proceed as described in paragraphs 8 to
15 inclusive, but in addition ensure that the
clip on the back of the inboard pad fits into
the piston recess (see illustration), refit the
caliper retaining clip, and ignore the reference
to the anti-rattle clips (see illustration). On
P100 models align the previously made marks
on the roadwheels and wheel studs.
Late model modification
21On some later models, slightly revised
front brake components are used. A new type
of retaining clip is used to secure the pads in
10•4Braking system
4.7 Correct and incorrect methods of freeing stuck outboard disc pad. Guide pin bolt (A)
must be in position - Girling caliper
4.9 Using a spreader tool to depress the
caliper piston into its bore
4.19 Withdraw the disc pads from the
caliper - Teves caliper4.18 Withdrawing a caliper from its carrier
bracket - Teves caliper
4.17 Disconnect the pad wear sensor
wiring plug - Teves caliper

the caliper, and the caliper body is modified
accordingly. Also, plastic covers are fitted to
the caliper guide bolts (see illustrations).
22Procedures are unchanged from those
given above.
Rear disc pads
23Slacken the rear roadwheel nuts, chock
the front wheels, then jack up the rear of the
vehicle and support on axle stands. (see
“Jacking and Vehicle Support”). Remove the
roadwheel.
24The disc pads can be inspected through
the top of the caliper after removal of the
blanking spring clip. Check that the friction
material thickness is not less than the
minimum given in the Specifications.
25If any one of the pads has worn below the
specified limit, the rear pads must be renewedas an axle set (4 pads).
26To renew the pads, proceed as follows.
27Release the handbrake, and free the
handbrake cable from the suspension lower
arm by bending back the tangs.
28Where applicable, disconnect the wiring
to the disc pad wear sensor (see illustration).
29Unscrew and remove the bolt from the
forward caliper guide pin, while holding the
pin stationary with a spanner (see
illustration).
30Swing the caliper rearwards and lift out
the disc pads (see illustration). Do not
depress the brake pedal with the caliper
removed.
31Brush all dirt and dust from the caliper,
pads and disc, but do not inhale it as it may
be injurious to health. Scrape any corrosion
from the disc.32As the new pads will be thicker than the
old ones, the piston must be retracted into its
bore to accommodate the new thicker pads.
Retracting the piston will cause the fluid level
in the reservoir to rise, so to avoid spillage,
syphon out some fluid using an old
hydrometer or a teat pipette. Retract the
caliper piston by turning it clockwise. Ford
tool No 12-006 is designed for this purpose,
but a pair of circlip pliers or any similar tool
can be used instead (see illustration).
33Remove the backing paper from the new
pads, and fit them to the caliper.
34Further refitting is a reversal of removal,
bearing in mind the following points.
35If disc pads with wear sensors are fitted,
the pad with the sensor wire should be fitted
inboard.
36Repeat the procedure on the opposite
rear brake.
37On completion, switch on the ignition and
apply the footbrake hard several times to
settle the pads. Switch off the ignition, then
check and if necessary top-up the fluid level in
the reservoir. Check the operation of the
handbrake.
38Avoid heavy braking, if possible, for the
first hundred miles or so after fitting new
pads. This will allow the pads to bed in and
reach full efficiency.
Braking system 10•5
10
4.21a Later type front disc pad retaining
clip
4.32 Retracting the piston using circlip
pliers4.30 Lift out the disc pads
4.28 Rear disc pad wear sensor wiring clip
(arrowed)
4.29 Unscrewing the forward caliper guide
pin bolt
4.21b Removing a caliper guide bolt cover
- later type
4.20b Refitting the caliper retaining clip -
Teves caliper4.20a The clip on the back of the inboard
disc pad fits into the piston recess - Teves
caliper

neck with a rubber band, or by refitting the
cap. This will reduce the loss of fluid during
the following procedure.
3Disconnect the flexible fluid hose from the
rigid brake pipe under the wing of the vehicle,
or alternatively unscrew the flexible hose from
the union on the caliper. Take care not to twist
the hose, and plug the open ends to prevent
fluid loss and dirt ingress.
4Remove the disc pads.
5On models fitted with Girling calipers (1.3
and early 1.6 litre models) (see illustration),
unscrew and remove the bolt from the lower
caliper guide pin, while holding the pin
stationary with a spanner, then remove the
caliper.
6On models fitted with Teves calipers (later
1.6, 1.8 and 2.0 litre models) (see
illustration), remove the caliper from the
vehicle.
7If required, the caliper carrier bracket can
be unbolted and removed from the hub
carrier.
Overhaul
8Brush away all external dirt and dust, but
take care not to inhale any dust as it may be
injurious to health.
9Pull the dust-excluding rubber seal from the
end of the piston.
10Apply air pressure to the fluid inlet union,
and eject the piston. Only low air pressure is
required for this, such as is produced by a
foot-operated tyre pump. Position a thin piece
of wood between the piston and caliper body
to prevent damage to the end face of the
piston in the event of its being ejected
suddenly.
11Using a suitable pointed instrument, prise
the piston seal from the groove in the cylinder
bore. Take care not to scratch the surface of
the bore.
12Clean the piston and caliper body with
methylated spirit and allow to dry. Examine
the surfaces of the piston and cylinder bore
for wear, damage and corrosion. If the piston
surface alone is unserviceable, a new piston
must be obtained, along with seals. If the
cylinder bore is unserviceable, the complete
caliper must be renewed. The seals must be
renewed regardless of the condition of the
other components.
13Coat the piston and seals with clean
brake fluid, then manipulate the piston seal
into the groove in the cylinder bore.
14Push the piston squarely into its bore.
15Fit the dust-excluding rubber seal
between the piston and caliper, then depress
the piston fully.
Refitting
16Refit the caliper and where applicable the
carrier bracket by reversing the removal
operations. Tighten the mounting bolts to the
specified torque.17On P100 models, when refitting the
roadwheel align the previously made marks
on the roadwheel and wheel stud.18On completion, bleed the front brake
circuit.
Braking system 10•9
10
6.6 Exploded view of Teves front disc caliper
A Guide bolts
B Caliper carrier bracket
C Caliper retaining clipD Disc pads
E Dust-excluding seal
F Piston sealG Piston
H Caliper
6.5 Exploded view of Girling front disc caliper
A Caliper
B Guide pin and dust
bootC Piston seal
D Piston
E Dust-excluding sealF Disc pads
G Caliper carrier bracket