Datsun 1968-1973 510 Owners Workshop Manual page 156

Chapter
9
BraklRg
system
155
3
Withdraw
the spring pon and cotter pin whIch
connects
the
control
gUIde
wIth the control bracket lower the
assembly
and
11ft away from inside the
car
4
Refitting the control
IS
the
reverse
sequence to
removal
lubricate all moving parts wIth
a
little lithIum based grease It
may be necessary
to
adjUst
the handbrake
as
deSCribed
In
Section
28
32 Check valva
removal and
raplacemant
On models fitted wrth
a vacuum servo Unit
a
small check
valve
IS
fItted
on
the
vacuum
lone and attached
to
the bulkhead
If
ItS
operation be suspect the
car
should be taken to the local
dealer for
a
pressure
test
To
remove
the valve undo and
remove
the securmg bracket
retaonong
screws
and 11ft away the
bracket Slacken the
two clips
and detaCh the
two
hoses
Refitting
the check valve
IS
the
reverse
sequence
to
removal
33 HydraulIC
p
and hoses
1
Penod callV
all
brake pIpeS
pIpe
connect OnS
and
umons
should be carefully
examined
2
First
examine
for
s
gns of
leakage
where the Pipe
unions
occur
Then
examine
the fleXible hoses for signs of
chafing and
fraymg and of
cause
leakage ThiS
IS
onlV
a
prellmmary part of
the fleXible
hose Inspection
as
exterior condition does not
necessarily Indicate the
fOtenor
condlt
on
whIch will be
considered
later
3 The
steel pIpes
must
be examIned
carefully
and
methodIcally
They
must
be cleaned off and examined for
any signs of dents
or
other damage
and
rust
and
corroSIon
Rust and
corrOSion
should be scraped off and If the
depth of
pItting In
the pIpeS
IS
20 Fault
finding
sIgnIfIcant they will
need replacement ThIS
IS
partIcularly
likely
on
those
areas
underneath
the
cer body
and
along the rear
axle
where tha
pIpes ara
exposed
to
full face of road and weather
conditions
4 If any
sectIon
of pIpe
IS to
be taken
off forst wipe
and then
remove
the
flUId reservoor
cap
and place
a
pIece of
polythena
OYer
the
reservoor
Refit the cap ThIS WIll
stop lyphonong durong
subsequent operatIOns
5 RIgId
pIpe removal
IS usually
qUite
straIghtforward The
unions
at each end
are
undone the Pipe and
unton
puUed
out
and
the
centre
sectIons of the
pIpe removed from tha
body clips
where the pIpes
are
exposed
to
full force
or
road
and weather
sometImes
be very
tIght
As
ona can only use an
open
ended
spanner and the
unIons are not
large burrong
of tha flats
IS
not
uncommon
when
attemptong
to
undo them
For thIS
reason a
self
Iockong
gnp
wrench
mole
IS
often the only
wey
to remove
a stubborn
uOlon
6
Removal
of fleXIble hoses
IS
descrobed
In
SectIon 6
7
WIth
the
fleXIble
hose removed
examlna
the ontamal
bore If
It IS
blown through flm
It
should be
posslbla to
see
through It
Any specks
of
rubber
whICh
come
out
or
Signs of restrictIOn
In
the bore
means
that the rubber lining
IS
breakong
up
and tha
pIpe
must
be replaced
8 R
Ig d pIpes
which
need
replacement
can
usually
be
purchased
at
any garage where they have the
pIpe umons
and
specIal
tools
to make them up All
they
need
to know IS the
total
length
of
the pIpe
the type of flare used
at
each end WIth the
unIon
and
the
length
and
thread
of the
unIon
9
Replacement
of pIpe
IS
a
straIghtforward
revenal
of
the
removal procedure If the rlgld pIpes have been
made up
It
beSt
to get all the
sets
tbends
In
them
before tryong
to
onstall them
Also If
there
are any acute
bends ask
your
supplier
to
put
th
on
for
you
on a
special
tube bender
Otherwosa
you mey
kink tha
pIpe and thereby decrease the bore
area
and flUId
flow
10 W th
the pIpes
replaced
remove
the
polythane
from the
reservoor
cap and bleed the system
as
descrobed
on
SectIon 5
Symptom
Reason
s Remedy
PEDAL TRAVELS ALMOST TO flOOR BEFORE
BRAKES
OPERATE
leaks and
air
bubbles
In
hydraulic
Brake flUId level
too low
system
Wheel cylinder
Or
caloper leakong
Master cylonder leakong bubbles
In
master
cylinder flUId
Brake
flexIble
hose
leakIng
Brake
hne fractured
Brake system
unions
loose
Normal
wear Linings
over
75
worn
Brakes badly
out
of adjustment
BRAKE PEDAL FEELS SPRINGY
Brake
Ilnmg renewal
New
IImngs not
yet bedded
on
Excessive
wear or damage
81 ake drums
or diSCS badly
worn
and weak
or
cracked
Master cylinder
securrng nuts
loose
L ck of
rnalntenanre
BRAKE PEDAL
FEELS
SPONGY
AND SOGGY
leaks
or
bubblps m hydrauliC
system
Wheel cylinder
or
caliper leakmg
Master
cylinder lpakmg
bubbles
In master
cylmder
reservoir
Top
up
m
cylinder
reservoir
Check for
leaks
DIsmantle wheel
cylinder
or
IIper clean
fIt
new
rubbers and bleed brakes
DIsmantle master cyllnoar
clean end
frt
new
rubbers Bleed brakes
Examone and fIt
new
hose
If old hose leak
g
Bleed
brakes
Replace WIth
new
brake pIpe Bleed
brakes
Check all
unions n
brake system
and
tlghten
as
necessary Bleed
brakes
It
replacement shoes and braka IInongs
or
pads
Jack lip
car
and adjust brakes
Use brakes gently until sprongy pedal
feeling
leaves
F
It
new
brake drums
or
din
T
ghten
master
ryllnder securong nuts
En
sure
prmg washers
are
fitted
D smantle wheel
cylinder
or caliper
clean
fIt
new
rubbers and
bleed
brakes
Dismantle
mastpr
cylinder clean and fit
new
rubbers and bleed brakes
Replace
cylinder
If ternal walls
scored