7 Unscrew the master cylinder reservoir cap,
and top up the reservoir to the “MAX” level
line. Do not invert the cap or hydraulic fluid
may short out the cap contacts causing the
warning light on the instrument panel to flash.
Refit the cap loosely, and remember to
maintain the fluid level at least above the
“MIN” 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
wherever 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 instructions, 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 correct
sequence must be followed (paragraphs 11 to
15) to ensure the removal of all air from the
system.
Bleeding sequence
11 If the hydraulic system has only been
partially disconnected and suitable
precautions were taken to minimise fluid loss,
it should only be necessary to bleed that part
of the system (ie the primary or secondary
circuit).
12 If the complete system is to be bled, then
it should be done in the following sequence:
Non-ABS models
(a) Left-hand front wheel.
(b) Right-hand rear wheel.
(c) Right-hand front wheel.
(d) Left-hand rear wheel.
ABS-models
13 Two types of ABS system may be fitted to
models covered by this manual. Although
generally similar in operation, the bleeding
sequence is different for each, and it is
necessary to identify the system being
worked on before proceeding.
14 The easiest way to distinguish between
the two types is to locate the hydraulic
modulator unit in the engine compartment
and note the arrangement of the hydraulic
pipe connections. On the early type modulator
there are six pipe connections; four on the
upper face and two on the front face. On the
later modulator there are also six pipe
connections but all are on the front face of the
unit.
15 Having identified the unit fitted, the
bleeding sequence is as follows:
Early type modulator
(a) Left-hand front wheel.
(b) Right-hand rear wheel.
(c) Right-hand front wheel.
(d) Left-hand rear wheel.
Later type modulator
(a) Left-hand front wheel.
(b) Right-hand front wheel.
(c) Left-hand rear wheel.
(d) Right-hand rear wheel.
Bleeding - basic (two-man)
method
16 Collect a clean glass jar and a length of
plastic or rubber tubing, which is a tight fit
over the bleed screw, and a ring spanner to fit
the screws. The help of an assistant will also
be required.
17 If not already done, remove the dust cap
from the bleed screw of the first wheel to be
bled and fit a spanner and tube to the screw.
18 Immerse the other end of the bleed tube
in the jar, which should contain enough fluid
to cover the end of the tube.
19 Ensure that the master cylinder reservoir
fluid level is maintained at least above the
“MIN” level line throughout the procedure.
20 Open the bleed screw about half a turn,
and have your assistant depress the brake
pedal with a smooth steady stroke down to
the floor, and then hold it there. When the flow
of fluid through the tube stops, tighten the
bleed screw and have your assistant release
the pedal slowly.
21 Repeat this operation (paragraph 20) until
clean brake fluid, free from air bubbles, can
be seen flowing from the end of the tube.
22 When no more air bubbles appear, tighten
the bleed screw, remove the bleed tube and
refit the dust cap. Repeat these procedures
on the remaining bleed screws in sequence
until all air is removed from the system and
the brake pedal feels firm again.
Bleeding - using a one-way
valve kit
23 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
incorporate a translucent container, which
can be positioned so that the air bubbles can
be more easily seen flowing from the end of
the tube.
24 The kit is connected to the bleed screw,
which is then opened. 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.
25 Note that these kits simplify work so
much that it is easy to forget the master
cylinder fluid level; ensure that this is
maintained at least above the “MIN” level line
at all times.
Bleeding - using a pressure-
bleeding kit
26 These kits are usually operated by the
reserve of pressurised air contained in the
spare tyre. However, note that it will be
necessary to reduce the pressure to a lower
level than normal; refer to the instructions
supplied with the kit.
27 By connecting a pressurised, fluid-filled
container to the master cylinder reservoir,
bleeding is carried out by opening each bleed
screw in turn (in the specified sequence) and
allowing fluid to run out, rather like turning on
a tap, until no air bubbles can be seen in the
expelled fluid.
28 This method has the advantage that the
large reservoir of fluid provides an additional
safeguard against air being drawn into the
system during bleeding.
29 Pressure bleeding is particularly effective
when bleeding “difficult” systems, or when
bleeding the complete system at the time of
routine fluid renewal.
All methods
30 When bleeding is completed, check and
top up the fluid level in the master cylinder
reservoir.
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 indicated.
Failure to bleed satisfactorily after a
reasonable repetition of the bleeding
operations may be due to worn master
cylinder seals.
32 Discard brake fluid which has been bled
from the system; it will not be fit for re-use.
3 Front brake pads -
renewal
2
Warning: Disc brake pads must
be renewed on both front
wheels at the same time - never
renew the pads on only one
wheel as uneven braking may result. Dust
created by wear of the pads may contain
asbestos, which is a health hazard. Never
blow it out with compressed air and do not
inhale any of it. DO NOT use petroleum-
based solvents to clean brake parts. Use
brake cleaner or methylated spirit only. DO
NOT allow any brake fluid, oil or grease to
contact the brake pads or disc. Also refer
to the warning at the start of Section 2
concerning the dangers of hydraulic
fluid.
Note: New caliper lower guide pin bolts will be
required for refitting.
1 Apply the handbrake, remove the front
wheel trim and slacken the wheel nuts. Jack
up the front of the car and support it on axle
stands. Remove the front roadwheels.
2 Where fitted, disconnect the pad wear
warning light wiring plug (left-hand caliper
only) and using a spanner, unscrew the lower
Braking system 9•3
9
1380 Rover 800 Series Remake
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