Datsun 1968-1973 510 Owners Workshop Manual page 143

142
Chapter
9
Brakmg
system
13 Front
dnlm
brake backplate
ramoval and
replacement
1 To
remove
the
backplate refer
to
SectIon 11 and
rem e
the
drum
as
descrIbed
In
paragraphs
1 to 3 inclusIve
2 Refer
to
Chapter 11
and
rem e
the
front hub
assembly
3 Refer
to
SectIon 6
and
dIsconnect
the
flexIble hose
4 Bend back the lock IBb and undo and
remove
the four
securing
bolts and
lockwashers securing the backplate
to
the
SWIVel axle
5
The backplate essembly
may
now
be
lofted
over
the
stub
6
RefItting
IS
the
reverse sequence to
removal It WIll
be
necessary
to
bleed the
hydrauloc
system
as
described
In
SectIon
5
14 Rear drum brake shoes
InspectIon removal
end replacement
Refer
to
the
IntroductIon
of
SectIon 11
2 Chock the front
wheels Jack
up the
rear
of the
car
and
support
on firmly based stands
remove
the
road wheel
3
Refer
to
SectIon
4 and back off the
brake adjuster
4
The
drum may
now
be removed from the wheel studs If
It IS
tIght
use a
10ft faced hammer
and tap
outwards
on
the
circum
ference rotating
thedrum whIlst
completing
thIS
operatIon
5
Inspect the Ionlng thIckness
as
described
In
SectIon
11
paragraph 4
6 Where brake shoes
antI
rattle springs
are
fItted
use a
paIr of
ploers and
rotate the
retainer
through
900and loft away the
retamer spring seat and pm
7
521 modelL Carefully
open
out
the brake shoe
assembloes
with
a
screwdriver and
remove
the
extension
link
8 Make
a
note of
the locatIons of the shoe
return
springs
and
the way round
they
are
fItted
Carefully
ease
the shoes from the
slots
In
thewheel
cylonder
and
adluster
9
lIft the shoes and
return
springs from the backplate On 521
models
It
WIll be necessary to
unhook the
handbrake cable from
the
toggle
lever
I
10
Refer
to
SectIon
11
paragraphs
8
to 15
for
InformatIon
on
cleaning
and also
reassembly whIch
IS
the
reverse
sequence
to
removal
15
Rear
drum
brake wheel
cylonder
removal
InspectIOn
and
overhaul
510 models
1
Refer
to
the IntroductIon
to
SectIon 12
2 Remove the brake drum
and
shoes
as
deSCribed
In
Section 14
3
Clean
down the
rear
of the
backplate
uSing
a
stIff brush
Place
a quantItY
of
rag
under the backplate
to
catch
any
hydrauhc
flUId that may
Issue
from
the
open pIpe
or
wheel
cyhnder
4
WIpe
the top of the brake master cylonder
reservoir
and
unscrew
the cap
Place
a
pIece
of thick polythene
over
the
top
of
the
reservoir
and replace the cap ThIS
IS to
stop
hydraulic flUId
syphonlng
out
5
WIpe the
unIon
of the
rear
of the wheel cylinder and dIS
connect the
metal
pIpe
6
StraIghten
the
ears
and WIthdraw the split
Pin locking
the
handbrake cable
yoke
cotter pin
to
the lever
at
the
rear
of the
wheel cylinder Remove the
cotter pin
7 Ease off the rubber boot from the
rear
of the wheel cylinder
8
USing
a
screwdriver
carefully
draw off the
retaining plate
spring
plate and shIms from the
rear
of the wheel cylinder
9 The
wheel
cylinder
may
now
be lifted away from the
brake
backplate
Detach the handbrake lever from
the
wheel
cylinder
10 To dIsmantle
the wheel
cylinder
first
ease
off
the rubber
retaining
rmg WIth
a
screwdriver and the rubber dust
cover
Itself
11 WIthdraw
the pIston from the wheel cylinder body
and WIth
the fingers
remove
the
piston
seal from the piston noting which
way round
It IS
ttted Do
not use
a
metal screwdnver
as
thiS
ratch the
s to
12 Inspect
the inSIde of
the
cylinder
for
ore
marks caused by
ImpurItIes
In
the hydraulic flUId
NOTE
If the
wheel cyhnder
requires
renewal always enSUre
that the
replacement
IS
exactly
IndentlCal
to
the
one
removed
13 If the
cylinder IS
sound
thoroughly clean
It
out WIth fresh
hydraulic flUId
14 The
old
rubber seal WIll
probably
be swollen
and VISIbly
worn
Smear
a new
rubber 1 WIth
hydraUlic flUId and refIt the
correct
way round to the pIston
15
I
nsert
the
pIston
Into the bore taking care not to
roll the lip
of the seal and fIt
a new
dust seal
and retaining
ring
16 USing brake
grease
smear
the
backplate
where the wheel
cylindEr slides and refIt the handbrake lever
on
the wheel
cyhnder
ensurong that
It IS
the correct way round
The spindle of
the lever
must engage
In the
recess on
the cylinder
rims
17
Slide
the shIms and spring
plate
between
the wheel cylinder
and backplate
The
retaining
plate
may now
be Inserted between
the
spring
plate and wheel
cylinder
taking
care
the pIpS of the
sprong
plate
engage WIth the holes of the
retaining plate
18 Replace the rubber boot and reconnect the
handbrake
cable
yoke
to the
handbrake
lever Insert the cotter
pin head upwards
and lock With
a new
spIlt
pin
19
Reassembling
the
brake
shoes
and drum
IS
the
reverse
sequence
to
removal
Finally
bleed the
hydraulic
system
as
J
descrobed
In
SectIon
5
I
16
Rear drum
brake wheel
cylinder
removal
InspectIOn
and
overhaul
521 models
1
Refer to
the Introductlon to
Sectton 12
2
Remove the brake drum and shoes
as
descrobed
In
SectIon
14
3 Clean down the
rear
of the
backplate
uSing
a
stIff brush
Place
a
quantIty of
rag
under the backplate
to
catch
any
hydrauhc
flUid that may
Issue
from
the
open pipe
or
wheel
cylinder
4 WIpe the
tOP
of
the
brake master cyhnder reservoir
and
unSCrew
the cap Place
a
pIece of polythene
over
the top of the
reservoir
and replace the cap
ThIS
IS to
stop
hydrauhc flUId
syphonlng out
5
WIpe the
Union at
the
rear
of thewheel cylinder and
unscrew
the
connector bolt
lIft
away the
two
washers
one
each SIde of
the
connector
6
Undo and
remove
the four
nuts and
sprong
washers that
secure
the wheel cylinder
to
the
backplate
loft away the wheel
cylinder
7 To dIsmantle the wheel cyhnder fIrst
remove
the
two
dust
covers
Withdraw the
two
piston
leads and then the pistons
Remove the seal from
each piston noting which way round
It IS
fItted
8
Inspect
the wheel cylinder
as
descrobed
In
SectIon 15 para
graphS
12
and
13
9 The old rubber seals Will probably be swollen and VISIbly
worn
Smear
the
new
rubber
seals With
hydraulic
flUId and refIt
to
the
pistons making sure
that the lips face Inwards when
assembled
10 I
nsert
the
pIstons
Into
the bore
takIng
care
not to
roll the
lop
of the
seal Replace
the
two
pISton heads and then the dust
coverS
11
Refitting
the wheel
cylinder IS
the
reverse
sequence to
remOY
al
12
When the shoes
and
drum have been
replaced
bleed the
hydraulic
system
as
deSCribed
In
Section 5
17 Rear drum brake ad5uster
assembly
510 models
rem al mspectlon
and
re
Remove the brake drum and shoes as
deSCribed
In
SectIOn 14
2 Remove rubber boot adjuster shim
lockp1ate
and spring
lIft
the
adjuster
away from the
backplate
3 Remove the adjuster head and
ItS
shim and slide
out
the
adjuster
wheel and
scr a e blY
Re Tl9
Jhe
rew
from the