MG MGB User Manual

Ma
THE
BRAKING SYSTEM
Section
Ma.1
PEDAL FREE
MOVEMENT
A
free
movement
of
%in. (3.2
mm.)
measured
at
pedal pad
must
be
maintained
on
the brake
pedal.
To adjust
the
free
movement,
slacken the
stop
light switch
locknut
and
turn
the
switch clockwise
to
decrease
or
anticlockwise
to
increase
the
clearance. Tighten
the
stop
light
switch locknut.
Section Ma.2
TANDEM
MASTER
CYLINDER
Removing
1.
Remove
the
four
screws
securing
the
master
cylinder
cover
and
remove
the
cover.
2.
Drain
the
fluid from
the
reservoir
as
follows:
a.
Attach
a
rubber
tube
to
one
of
the front brake
calliper
bleed
screws.
~
b.
Attach
a
rubber
tube
to
one
of the
rear
wheel
brake cylinder
bleed
screws.
c.
Slacken
both
bleed
screws
one
complete
turn.
(1. Depress
the brake
pedal,
hold
it in
the down
position
and tighten
the bleed
screws.
e.
Repeat
the operations in
(d.)
until
the
reservoir
is
empty.
3'.
Drain
the
clutch
master
cylinder reservoir
by the
same
method
on
the brakes
from the slave
cylinder
bleed
screw.
4.
Disconnect
the
pipes
from the brake
master
cylinder
and plug
the
pipe
ends.
5. Disconnect
the
pipe
from the
clutch
master
cylinder
and plug the
pipe
and connection.
6. Remove
the split
pin
and clevis
pin
from
the
push—rod
and disconnect
the
pedal lever.
Disengage
the
clutch and
brake
pedal
return
springs.
Remove
the
left-hand
lower
fascia
panel.
9.
Unscrew
the
two
bolts
securing
the
pedal box
to
the
toe-plate.
10.
Unscrew
the
nut
retaining
the
pedal
pivot
bolt,
withdraw
the
bolt,
remove
the
centre
spacer
and
temporarily re■t
the bolt.
11.
Unscrew
the
six
bolts securing
the
pedal box
to
the
bulkhead
and
remove
the
pedal box
complete
with
master
cylinders and
pedals.
12.
Unscrew
the
two
bolts
securing
the
brake
master
cylinder
and
remove
the
master
cylinder.
90>!
Dismantling
13.
Ensure
that
the
pipe
connections
are
securely plugged
and the
reservoir
cap
is
fitted and
thoroughly
clean
the
exterior
of the
assembly.
14.
Detach the rubber
boot
and withdraw
the
push-rod.
15.
Grip
the cylinder
body
in
a
soft-jawed
vice
with the
mouth of the bore
uppermost.
Q
‘_
Ma.2
.4‘
a
$024
2W
Fig. Ma.l
Brake
pedal adjustment
1
Switch locknut.
2.
Stoplight switch.
A
=
e
in. (3.2 mm.).
16. Compress the
return
spring
and
remove
the Spirolox
ring
from
its
groove
in
the
primary piston,
taking
care
not to
distort
the coils of the
ring
or score
the
bore
of
the
cylinder.
17.
Using tool 18G
1112,
remove
the
piston retaining
circlip.
18. Move
the
piston
up
and down
in
the bore
to
free the
nylon guide bearing and
cap
seal;
remove
the guide
bearing and
seal.
19. Remove
the plain washer.
20. Using tool 18G
1112,
remove
the
inner
circlip.
21. Withdraw the
primary
and
secondary
piston
assembly
complete with
stop
washer.
22. Remove
the
stop
washer.
23.
Compress the
spring separating
the
two
pistons
and
drive
out
the roll-pin
retaining
the
piston
link.
24.
Note the
positions
of
the rubber
cups
by
their
moulded identations and
remove
the
cups
and washers
from the
pistons.
25. Unscrew
the four bolts
securing
the plastic
reservoir
to
the body and
remove
the
reservoir.
26. Remove the
two
reservoir
sealing
rings.
27.
Unscrew the front brake
pipe'connection
adaptor and
discard the
copper
gasket.
28.
Withdraw the
springs
and
trap
valves
from the
connection
ports.
Inspection
29.
Clean all the
parts
thoroughly
using
the recommended
brake
■uid
and dry them with
clean
lint-free
cloth.
30.
Examine
the
metal
parts
for
wear
and damage;
inspect
the rubber
components
for swelling, perishing,
distortion
or
any
other
signs
of
deterioration. Renew
all
worn,
damaged,
or
suspect parts.
Reassembling
31. Dip all the internal
components
in
the recommended
brake ■uid and assemble them while
wet.
MGB.
Issue2. 25729

MG MGB Specifications

General

Brand	MG
Model	MGB
Category	Automobile
Language	English