Ford Thunderbird 1967 - Page 9

2-2
GROUP
2-Brakes
specification,
make
several
additional
forward
and
reverse stops
as
outlined
above.
6. If
the
second
series
of stops
do
not
bring
the
brake pedal
travel
with
in
specification,
remove
the brake
drums
and
check
the
brake
adjusters
to
make
sure
they
are
functioning.
Check
the
brake linings for
wear or
damaged parts
and
non-functioning
ad
justers.
Adjust
the brake
lining
out
side
diameter
to the
approximate in
side diameter
of the
brake drum
with
Rotunda
Tool
HRE-8650
(Fig.
11,
Part
2-2).
7.
If all
the
brake
adjusters,
brake
drums
and
linings are
functional and
the
brake
travel is not
within
specifi
cations,
check
the pedal
linkage
for
missing
bushings or
loose
attachments.
Bleed
the brakes
and
centralize the dif
ferential
valve.
POWER
BRAKE
FUNCTIONAL
TEST
1.
With the
transmission in
neutral,
stop
the
engine and
apply
the
parking
brake.
Depress
the
brake pedal
sev
eral
times
to
exhaust all
vacuum in
the
system.
2.
With the engine
shut
off,
exhaust
all
vacuum in the
system.
Depress the
brake
pedal
and hold it in the
applied
position.
If the
pedal
gradually
falls
away
under
this
pressure,
the
hydrau
lic
system is leaking.
Check
all
tubing,
hoses
calipers,
wheel
cylinders
and
con
nections
for leaks.
3.
With the
engine shut
off and all
vacuum in
the
system
exhausted,
de
press the
pedal
and hold
it in the
ap
plied
position.
Start
the engine.
If
the
vacuum
system
is
operating,
the
pedal
will
tend to
fall
away
under foot
pres
sure
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.
If
the
brake
pedal
movement
feels
spongy,
bleed the
hydraulic
system
to
remove
air from
the
system.
Refer
to
Hydraulic
System
Bleeding,
Section 2.
Also,
check
for
leaks or insufficent
fluid.
LOCKED
WHEEL
BRAKE
Should
one
of
the
wheel
brakes be
locked
and
the
vehicle
must be
moved,
open
the
bleeder
screw
long
enough
to
let
out
a
few drops
of
brake fluid.
This
bleeding
operation
will
release
the
brakes
but
will
not
correct the
cause
of
trouble.
VACUUM
TESTS
VACUUM
RELEASE
PARKING
BRAKES
Visually
check
the
operation of
the
brake
linkage
as the
park
brake
ped
al
is
depressed.
Then,
check
the
opera
tion
of
the
brake
linkage
when
the
manual
release
lever
is
activated.
These
checks
should
indicate
whether
the
manual
parking
brake
control
link-
2-11/32"
DIMENSION
TO
BE
MEASURED
PARALLEL TO
THE VERTICAL CENTERLINE
OF
THE
STEERING
COLUMN
WITH A
50
LB. LOAD
APPLIED
TO THE
CENTERLINE
OF
THE
BRAKE PEDAL
PAD.
STEERING
COLUMN
CENTERLINE
STEEL
MEASURING
TAPE
METAL
DASH PANEL
FIG. 7 Brake
Pedal Height
and
Travel
Measurements
Too/-WRE-500-50
H1536-A
^m
'
*
^1
W&F
'
M^m ^^^^H
'
'
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^MC^^
^'
^ Vtfl
^p
*
^B
jj^
jLjHJ
SkR
m
iL
WL*
jH
Ik.*
>afl
HnC^I
MPP
0'H
HI
525
-A
FIG.
2 Brake
Pedal Pressure
Gauge
age
is
operating
properly
or requires
repair
or
adjustment
due
to
inability
of
the
parking
brake
to hold against
moderate vehicle
movement.
Perform
tests
of the
parking
brake system
and
controls
after
making
certain the
link
age
and manual controls
operate
pro
perly.
Diagnosis ot
vacuum
rctease sys
tems
is
basically
similar
to
electrical
diagnosis.
That
is,
the vacuum
system
must be
complete
from
the
source
to
the
vacuum components.
Any
leaks,
like
a
bad
connection,
will
make the
system
inoperative. If a leak develops
in
one
of
the
vacuum
systems,
one or
all of
the
vacuum components
may
be-
Ins tailed
come
inoperative.
This would
be de
pendent on
the
location
of the
vacuum
leak.
If
the leak
is
in
the vacuum
sup
ply,
all systems
will become
inopera
tive.
If
the leak
is
in
the component side
of
the vacuum
control
for
the
specific
system,
all other
systems
will operate
when the
leaking
system is
off.
When
testing
a
parking
brake vac
uum
release
system,
a minimum
of 10
inches
of vacuum
(Hg.)
should
be
available at all
points
where
vacuum
is
applied.
This
can
be checked with a
Rotunda Fuel
Pump
Tester
Gauge
(ARE
345)
and
two
Distributor Tester
hose
adapters(
Marked Q)connected
to-