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2-2
GROUP 2 - Brakes
CENTERLINE OF
STEERING COLUMN
VEHICLE
FORD-MERCURY
FORD-MERCURY
FORD
TYPE
N0
B*ff
ER
POWER
DISC
NON-POWER
DISC
A
MAX.
7.91
6.40
8.70
MIN.
6.92
5.14
7.65
•
MAX.
2.90
3.10
2.28
TOEBOARD
OR DASH METAL
" A " DIMENSION TO BE MEASURED TO SHEET METAL.
" B " DIMENSION TO BE MEASURED PARALLEL TO THE VERTICAL CENTERLINE
OF THE STEERING COLUMN WITH A 50 POUND LOAD APPLIED TO THE
CENTERLINE OF THE BRAKE PEDAL PAD. (CHECKS ON POWER BRAKE
VEHICLES MADE WITH ENGINE RUNNING)
H 1544-B
FIG. 7—Brake Pedal Height and
Travel Measurements
Tool
-WRE-500-SO
FIG. 2—Brake Pedal Effort
Gauge Installed
Measure and record the distance from
the brake pedal free height position to
the reference point, which is at the six
o'clock position on the steering wheel
rim.
3. With the steel tape still hooked
to the brake pedal depress the brake
pedal by pressing downward on the
brake pedal effort gauge. Apply a 50
pound load to the center of the pedal
by observing the pressure gauge, and
measure the distance from the brake
pedal to the fixed reference point on
the steering wheel rim parallel to the
centerline of the steering column.
4. The
difference
between
the
brake pedal free height and the de-
pressed pedal measurement under a
50 pound load should be within the
specified maximum pedal travel serv-
ice specification B in Fig. 1.
5. If the pedal travel is more than
the specified maximum shown in Fig.
1, dimension B, make several sharp
reverse stops (equivalent to 50 pounds
pedal pressure) with a forward stop
before each. Move the vehicle in
reverse and forward for a distance of
approximately ten feet; then apply
the brakes sharply and hold the brake
pedal down until the vehicle is com-
pletely stopped. This will actuate the
i>nke self-adjusters. If these stops do
not bring the brake pedal travel with-
in specification, make several addi-
tional 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
damage. Repair or replace all worn
or damaged parts and non-function-
ing adjusters. Adjust the brake lining
outside diameter to the approximate
inside diameter of the brake drum
with Rotunda Tool HRE-8650 (Figs.
12 and 13, Part 2-2).
7. If all the brake adjusters, brake
drums and linings are functional and
the brake travel is not within speci-
fications, check the pedal linkage for
missing or worn bushings, or loose
attachments, Bleed the brakes and
centralize the differential 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, 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, calipers (if
so equipped), wheel cylinders and
connections for leaks.
3. With the engine shut off and all
vacuum in the system exhausted, 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 ap-
plied 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, Part
1, Section 2, Also, check for leaks or
insufficient 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 brake pedal is
depressed. Then, check the operation
of the brake linkage when the manual
release
lever
is
activated.
These
checks should indicate whether the
manual parking brake control linkage
is operating properly or requires re-
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