General Brake Service; Diagnosis And Testing - Ford Thunderbird 1964 Shop Manual

PART 2-1
GENERAL
BRAKE SERVICE
PART 2-2
BRAKE SYSTEM
PAGE
.
2-1
PART 2-3
SPECIFICATIONS
PAGE
.2-21
2-6
PART
2-1
GENERAL BRAKE SERVICE
Section
Page
1 Diagnosis
and
Testing
2-1
2 Common Adjustments
and
Repairs 2-3
Section
3
Cleaning
and
Inspection
Page
. .2-5
DIAGNOSIS AND TESTING
PRELIMINARY TESTING
1.
Check
the
fluid level in
the
master cylinder, and add
FoMoCo
heavy-duty
brake fluid if
required.
2. Push
the
brake
pedal
down
as
far
as
it
will go while
the
engine
is
running
or vacuum
is in
system and
car
is
standing
still.
If
the
pedal
travels
more
than halfway
between
the
released position and
the floor,
check
the
brake
adjustment and
the
automatic adjusters.
To
check adjuster
operation,
check
the
shoes
and
the
adjuster com
ponents
for
binding
or
improper in
stallation and
follow
the
procedure
described
under
"Brake Shoe Ad
justments"
in Part
2-2,
Section 2.
Make
several reverse
brake
stops
to
ensure uniform adjustment at all
wheels.
3. With
the transmission
in
neu
tral,
stop
the
engine and
apply
the
parking brake.
Depress
the
service
brake
pedal several
times to
exhaust
all vacuum
in
the
system.
Then,
de
press
the
pedal and
hold it in
the
applied position.
Start
the
engine.
If
the
vacuum system
is
operating,
the
pedal will
tend to
fall away
under
foot
pressure and
less
pressure
will
be
required
to
hold
the
pedal
in
the
applied position.
If
no action
is
felt,
the
vacuum
booster
system
is
not
functioning. Follow
the
procedures
in
the
"Booster Diagnosis
Guide."
4. With
the
engine shut
off,
ex
haust
all vacuum
in
the
system.
De
press
the
brake
pedal and
hold it in
the
applied position.
If
the
pedal
gradually
falls
away
under
this
pres
sure,
the
hydraulic
system
is leaking.
Check
all tubing,
hoses,
wheel cylin
ders,
and
connections
for leaks.
If
the
brake
pedal movement
feels
spongy,
bleed
the
hydraulic
system
to
remove air
from
the
lines
and
cylinder.
See
"Hydraulic System
Bleeding,"
Section 2.
Also,
check
for
leaks
or
insufficient fluid.
5. Should
one of the
brakes be
locked
and
the
car
must
be
moved,
open
the
brake
cylinder
bleeder
screw
long
enough
to
let
out a
few
drops
of
brake fluid. This
bleeding
operation
will release
the brakes,
but it
will not correct
the
cause
of
the trouble.
ROAD TEST
The
car
should
be
road
tested
only
if the brakes
will
safely stop
the
car.
Apply
the
brakes
at a speed
of
25-30
mph to
check
for
the
exist
ence of
the
trouble
symptoms
listed
in Table
1,
with the
exception
of
brake
chatter
and
those
symptoms
resolved
in
the
preliminary tests.
For
each
of
the symptoms
encountered,
check and
eliminate the
causes which
are also
listed in
Table
1. To
check
for brake
chatter or
surge,
apply
the
brakes
lightly
at
approximately
50
mph.
For booster
removal
and
installa
tion
procedures,
refer to
-Part
2-2,
Section
3. For
disassembly
and
as
sembly procedures,
refer
to Part
2-2,
Section 4. For
cleaning
and
inspec
tion
refer
to
Part
2-1,
Section
3.