Ford Orion. Manual - part 49

that is being handled. Finally, it is
hygroscopic (it absorbs moisture from the
air) - old fluid may be contaminated and
unfit for further use. When topping-up or
renewing the fluid, always use the
recommended type, and ensure that it
comes from a freshly-opened sealed
container.

1 The correct operation of any hydraulic
system is only possible after removing all air
from the components and circuit; and this is
achieved by bleeding the system.
2 During the bleeding procedure, add only
clean, unused hydraulic fluid of the
recommended type; never re-use fluid that
has already been bled from the system.
Ensure that sufficient fluid is available before
starting work.
3 If there is any possibility of incorrect fluid
being already in the system, the brake
components and circuit must be flushed
completely with uncontaminated, correct
fluid, and new seals should be fitted
throughout the system.
4 If hydraulic fluid has been lost from the
system, or air has entered because of a leak,
ensure that the fault is cured before
proceeding further.
5 Park the vehicle on level ground, and apply
the handbrake. Switch off the engine, then
(where applicable) depress the brake pedal
several times to dissipate the vacuum from
the servo unit.
6 Check that all pipes and hoses are secure,
unions tight and bleed screws closed.
Remove the dust caps (where applicable), and
clean any dirt from around the bleed screws.
7 Unscrew the master cylinder reservoir cap,
and top-up the master cylinder reservoir to
the “Maximum” level. Remember to maintain
the fluid level at least above the “Minimum”
level line throughout the procedure, otherwise
there is a risk of further air entering the
system.
8 There are a number of one-man, do-it-
yourself brake bleeding kits currently available
from motor accessory shops. It is
recommended that one of these kits is used
whenever possible, as they greatly simplify
the bleeding operation, and also reduce the
risk of expelled air and fluid being drawn back
into the system. If such a kit is not available,
the basic (two-man) method must be used,
which is described in detail below.
9 If a kit is to be used, prepare the vehicle as
described previously, and follow the kit
manufacturer’s manuals, as the procedure
may vary slightly according to the type being
used; generally, they are as outlined below in
the relevant sub-section.

10 Whichever method is used, the same
sequence must be followed (paragraphs 11
and 12) to ensure the removal of all air from
the system.

Bleeding sequence

11 If the system has been only partially
disconnected, and suitable precautions were
taken to minimise fluid loss, it should be
necessary to bleed only that part of the
system (ie the primary or secondary circuit).
12 If the complete system is to be bled, then
it is suggested that you work in the following
sequence:
a)

Right-hand rear wheel.

Left-hand rear wheel.

Right-hand front wheel.

Left-hand front wheel.

Bleeding - basic (two-man)
method

13 Collect a clean glass jar, a suitable length
of plastic or rubber tubing which is a tight fit
over the bleed screw, and a ring spanner to fit
the screw. The help of an assistant will also be
required.
14 Remove the dust cap from the first screw
in the sequence (if not already done) (see
illustration). Fit a suitable spanner and tube
to the screw, place the other end of the tube
in the jar, and pour in sufficient fluid to cover
the end of the tube.
15 Ensure that the master cylinder reservoir
fluid level is maintained at least above the
“Minimum” level throughout the procedure.
16 Have the assistant fully depress the brake
pedal several times to build up pressure, then
maintain it down on the final downstroke.
17 While pedal pressure is maintained,
unscrew the bleed screw (approximately one
turn) and allow the compressed fluid and air to
flow into the jar. The assistant should maintain
pedal pressure, following the pedal down to
the floor if necessary, and should not release
the pedal until instructed to do so. When the
flow stops, tighten the bleed screw again.
Have the assistant release the pedal slowly,
and recheck the reservoir fluid level.
18 Repeat the steps given in paragraphs 16
and 17 until the fluid emerging from the bleed
screw is free from air bubbles. If the master
cylinder has been drained and refilled, and air

is being bled from the first screw in the
sequence, allow at least five seconds
between cycles for the master cylinder
passages to refill.
19 When no more air bubbles appear, tighten
the bleed screw securely, remove the tube
and spanner, and refit the dust cap (where
applicable). Do not overtighten the bleed
screw.
20 Repeat the procedure on the remaining
screws in the sequence, until all air is
removed from the system and the brake pedal
feels firm again.

Bleeding - using a one-way
valve kit

21 As their name implies, these kits consist
of a length of tubing with a one-way valve
fitted, to prevent expelled air and fluid being
drawn back into the system; some kits include
a translucent container, which can be
positioned so that the air bubbles can be
more easily seen flowing from the end of the
tube.
22 The kit is connected to the bleed screw,
which is then opened (see illustration). The
user returns to the driver’s seat, depresses
the brake pedal with a smooth, steady stroke,
and slowly releases it; this is repeated until
the expelled fluid is clear of air bubbles.
23 Note that these kits simplify work so
much that it is easy to forget the master
cylinder reservoir fluid level; ensure that this is
maintained at least above the “Minimum” level
at all times.

Bleeding - using a pressure-
bleeding kit

24 These kits are usually operated by the
reservoir of pressurised air contained in the
spare tyre. However, note that it will probably
be necessary to reduce the pressure to a
lower level than normal; refer to the
manuals supplied with the kit.
25 By connecting a pressurised, fluid-filled
container to the master cylinder reservoir,
bleeding can be carried out simply by opening
each screw in turn (in the specified sequence),
and allowing the fluid to flow out until no more
air bubbles can be seen in the expelled fluid.
26 This method has the advantage that the
large reservoir of fluid provides an additional

9•14 Braking system

17.22 Bleeding a front brake using a one-

way valve kit

17.14 Rear brake bleed nipple and dust

cap (arrowed)

Hydraulic fluid is an effective
paint stripper, and will attack
plastics; if any is spilt, it
should be washed off

immediately, using copious quantities
of fresh water.

safeguard against air being drawn into the
system during bleeding.
27 Pressure-bleeding is particularly effective
when bleeding “difficult” systems, or when
bleeding the complete system at the time of
routine fluid renewal.

All methods

28 When bleeding is complete, and firm
pedal feel is restored, wash off any spilt fluid,
tighten the bleed screws securely, and refit
their dust caps.
29 Check the hydraulic fluid level in the
master cylinder reservoir, and top-up if
necessary (Chapter 1).
30 Discard any hydraulic fluid that has been
bled from the system; it will not be fit for re-
use.
31 Check the feel of the brake pedal. If it
feels at all spongy, air must still be present in
the system, and further bleeding is required.
Failure to bleed satisfactorily after a
reasonable repetition of the bleeding
procedure may be due to worn master
cylinder seals.

18 Vacuum servo unit - testing,

removal and refitting

Testing

1 To test the operation of the servo, depress
the footbrake four or five times to exhaust the
vacuum, then start the engine while keeping
the footbrake depressed. As the engine starts,
there should be a noticeable “give” in the
brake pedal as vacuum builds up. Allow the
engine to run for at least two minutes, and
then switch it off. If the brake pedal is
depressed again, it should be possible to
detect a hiss from the servo when the pedal is
depressed. After about four or five
applications, no further hissing will be heard,
and the pedal will feel considerably firmer.
2 Before assuming that a problem exists in
the servo itself, check the non-return valve as
described in the next Section.

Removal

3 Refer to Section 12 and remove the master
cylinder.
4 Disconnect the vacuum hose at the servo
non-return valve by pulling it free. If it is
reluctant to move, assist it by prising it free
using a screwdriver with its blade inserted
under the elbow flange.
5 Working inside the vehicle, move the front
passenger seat fully rearwards, then peel
back the footwell trim from the inner bulkhead
on that side, to gain access to the two servo
bracket retaining nuts. Unscrew and remove
the nuts.
6 Unscrew and remove the four nuts securing
the servo unit to the mounting bracket (see
illustration).
7 Withdraw the servo unit so that its studs are
clear of the bracket and pivot the inner
bracket to one side. Extract the clevis pin to
release the actuating rod from its shaft, then
remove the servo unit.
8 Note that the servo unit cannot be
dismantled for repair or overhaul and, if faulty,
must be renewed.

Refitting

9 Refitting is a reversal of removal. Refer to
Section 12 for details of refitting the master
cylinder.

19 Vacuum servo unit vacuum

hose and non-return valve -
removal, testing and refitting

Removal

1 Depress the brake pedal three or four times
to exhaust any remaining vacuum from the
servo unit.
2 Carefully pull free and detach the servo
vacuum hose from the servo unit (see
illustration). If the hose is reluctant to move,
prise it free with the aid of a screwdriver,
inserting its blade under the flange of the
elbow.
3 Detach the vacuum hose from its inlet
manifold connection. Depending on the fixing
(see illustration), undo the union nut and
withdraw the hose, or press the hose and its

retaining collar inwards, then holding the
collar in, withdraw the hose.
4 If the hose or the fixings are damaged or in
poor condition, they must be renewed.

Non-return valve testing

5 Examine the non-return valve for damage
and signs of deterioration, and renew it if
necessary (see illustration). The valve may
be tested by blowing through its connecting
hoses in both directions. It should only be
possible to blow from the servo end to the
manifold end.

Refitting

6 Refitting is a reversal of removal. If fitting a
new non-return valve, ensure that it is fitted
the correct way round.

20 Handbrake shoes (disc

brake models) - renewal

Warning: The dust created by
wear of the shoes may contain
asbestos, which is a health
hazard. Never blow it out with

compressed air, and don’t inhale any of it.
An approved filtering mask should be worn
when working on the brakes. DO NOT use
petroleum-based solvents to clean brake
parts - use brake cleaner or methylated
spirit only.

Braking system 9•15

19.3 Servo vacuum hose detachment from

the manifold

Hose secured by union nut

B Hose secured by retaining collar

19.2 Detaching the vacuum hose from the

servo unit

18.6 Underside view of the servo unit (A)

mounting bracket nuts (B) and the

actuating rod connection (C)

19.5 Non-return valve in the servo vacuum

hose

1 Remove the rear brake disc as described in
Section 11.
2 Note the fitted positions of the springs,
adjuster and handbrake shoes (see
illustration).
3 Release the handbrake cable from the relay
lever, referring to Section 23 if necessary.
4 Remove the shoe steady springs by
depressing and turning them through 90º.
Remove the springs and pins.
5 Pull the lower ends of the shoes apart to
release the adjuster, then disconnect the
lower pull-off spring from both shoes (see
illustration).
6 Detach the upper ends of the shoes from
the handbrake cable relay lever, then
disconnect the upper pull-off spring and
remove the two handbrake shoes.
7 Renew the handbrake shoes if they are
significantly worn or in any way contaminated.
8 Clean the adjuster and its associated
components.
9 Clean the backplate, then apply a little high-
melting-point grease to the shoe contact
points.
10 Refitting the handbrake shoes is a
reversal of removal.
11 Repeat the procedure on the remaining
rear brake.
12 On completion, adjust the handbrake as
described in Chapter 1.

21 Handbrake lever -

removal and refitting

Removal

1 Chock the roadwheels to secure the
vehicle.
2 Remove the front seats as described in
Chapter 11.
3 Where applicable, remove the centre
console as described in Chapter 11.
4 Peel back the carpet from the area around
the handbrake lever to provide suitable
access the lever and fittings (see illustration).
Release the handbrake.
5 Detach the handbrake warning light lead
from the switch.
6 Prise free the retaining clip and remove the
primary cable pin (see illustration).
7 Undo the two retaining bolts, and remove
the handbrake lever and spreader plate.

Refitting

8 Refit in the reverse order of removal. Ensure
that the retaining bolts are securely tightened.
Check the handbrake adjustment as
described in Chapter 1 to complete.

22 Handbrake primary cable -

removal and refitting

Removal

1 Release the primary cable from the
handbrake lever, as described in the previous
Section.
2 Chock the front roadwheels, then jack up
the vehicle at the rear and support it on axle
stands.
3 Where applicable, detach the exhaust
system and remove the heat shields from the
underside floorpan to allow access to the
primary cable connections underneath the
vehicle (see Chapter 4).
4 Release the spring clip securing the pin,
and extract the equaliser/cable pin. Detach
the equaliser from the primary cable (see
illustration).
5 Detach the cable guide from the floorpan,
then withdraw the cable rearwards from the
vehicle.

Refitting

6 Refit in the reverse order of removal. Ensure
that the cable guide is secured in the floorpan,
and lubricate the pivot pin with a liberal
amount of high-melting-point grease.
7 Refit the exhaust system and heat shields
with reference to Chapter 4 (where
applicable).
8 Refer to Chapter 1 for details, and adjust
the handbrake as required before lowering the
vehicle to the ground.

23 Handbrake cable -

removal and refitting

Removal

1 Chock the front wheels, then jack up the
rear of the car and support it on axle stands.
Fully release the handbrake lever, and remove
the rear wheel(s).
2 Refer to the previous Section for details,

9•16 Braking system

Equaliser

B Primary cable
C Cable guide

D Equaliser pin and

spring clip

Relay lever

B Upper pull-off

spring

C Steady spring
D Brake shoe

Adjuster

Lower pull-off
spring

G Steady spring
H Brake shoe

22.4 Handbrake cable equaliser

components

21.6 Handbrake primary cable-to-lever pin

and retaining clip (arrowed)

21.4 Prise back the carpet for access to

the handbrake warning light switch lead

connection and lever mounting bolts

20.5 Handbrake shoe upper pull-off

spring (A), adjuster (B) and lower pull-off

spring (C)

20.2 Handbrake shoe components (rear

disc brake models)

and release the handbrake primary cable from
the equaliser.
3 Disengage the right/left-hand cable(s) from
the equaliser (as required).
4 Remove the lockpin from the adjuster, and
the spring clip from the cable guides on the
side concerned, then detach them from the
underbody (see illustration).

Drum brake models

5 Remove the rear brake drum(s) and shoes
as described in Sections 5 and 6 respectively.
6 Compress the handbrake cable retainer
lugs and release the cable from the backplate,
then pull the cable through. Release the cable
from the underbody fixings, and remove it
from the vehicle (see illustrations).

Disc brake models

7 Detach the handbrake return spring, then
disconnect the cable end from the handbrake
shoe relay lever.
8 Extract the circlip securing the handbrake
outer cable to the support bracket, and
withdraw the cable.
9 Release the cable from the underbody
fixings, and remove it from the vehicle.

Refitting

All models

10 Refitting is a reversal of the removal
procedure. Where applicable, refer to the
appropriate Sections for details on the
refitting of the brake shoes and drums.

11 When the cable is fully refitted (but before
lowering the vehicle rear wheels to the
ground) check and adjust the handbrake as
described in Chapter 1.

24 Brake pressure control

valves - removal and refitting

Warning: Hydraulic fluid is
poisonous; wash off immediately
and thoroughly in the case of
skin contact, and seek immediate

medical advice if any fluid is swallowed or
gets into the eyes. Certain types of
hydraulic fluid are inflammable, and may
ignite when allowed into contact with hot
components; when servicing the hydraulic
system, it is safest to assume that the fluid
IS inflammable, and to take precautions
against the risk of fire as though it is petrol
that is being handled. Hydraulic fluid is
also an effective paint stripper, and will
attack plastics; if any is spilt, it should be
washed off immediately, using copious
quantities of fresh water. Finally, it is
hygroscopic (it absorbs moisture from the
air) - old fluid may be contaminated and
unfit for further use. When topping-up or
renewing the fluid, always use the
recommended type, and ensure that it
comes from a freshly-opened sealed
container.

Removal

1 The pressure control valves are located in
the engine compartment, fixed to the left-
hand inner wing panel (see illustration).
2 To remove the valve assembly, first detach
the rigid brake pipes from the valves. As the
pipes are disconnected, tape over the
exposed ends, or fit plugs, to prevent the
ingress of dirt and excessive fluid loss.
3 Unscrew and remove the valve support
bracket retaining nut (under the wheel arch),
and remove the valve assembly from the
vehicle.
4 To remove the valves from the bracket,

slide free the retaining clips and detach the
valve(s).
5 Check the general condition of the
insulators; if necessary, renew them before
refitting.

Refitting

6 Refitting is a reversal of the removal
procedure.
7 On completion, bleed the complete
hydraulic system as described in Section 17.

25 Light-laden valve

(Van models) -
removal and refitting

Warning: Hydraulic fluid is
poisonous; wash off immediately
and thoroughly in the case of
skin contact, and seek immediate

Removal

1 For this operation, the vehicle must be
raised for access underneath at the rear, but
must still be resting on its wheels. Suitable
ramps (or an inspection pit) will therefore be
required. If positioning the vehicle on a pair of
ramps, chock the front roadwheels.

Braking system 9•17

23.6B Release the handbrake cable from

its locating clips

23.6A Compress the handbrake cable

retaining lugs to release the cable from the

brake backplate

23.4 Handbrake cable adjuster nut (A)

locknut (B) and lockpin (C)

24.1 Brake pressure control valves

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