Ford COUGAR 1968 Shop Manual page 13

PART
2-1-General Brake Service
and install the master cylinder cover
and gasket. Be sure the diaphragm
type gasket is properly positioned in
the master cylinder cover. When the
bleeding operation is completed, the
fluid level should be filled to within
1/4 inch from the top of the reservoirs.
7. If the primary (front brake)
system is to be bled, repeat steps 2
through 6 at the right front brake cal-
iper or cylinder and ending a t the left
front brake caliper or cylinder.
8. On disc brake equipped vehi-
cles be sure that the front brake pis-
tons are returned to their normal po-
sitions and that the shoe and lining
assemblies are properly seated by de-
pressing the brake pedal several times
until normal pedal travel isestablished.
9. Centralize the pressure differ-
ential valve. Refer to the Centralizing
the Pressure Differential Valve Proce-
dures which follow.
P R E S S U R E BLEEDING
Bleed the longest lines first. The
bleeder tank should contain enough
new Ford Brake Fluid to complete
the bleeding operation. Use Ford
brake Fluid-Extra Heavy Duty
-
Part
Number C6AZ-19542-A or equivalent
for all brake applications. The brake
fluid is colored blue for identification
purposes. Do not mix low temperature
brake fluid with specified brake fluid
during the bleeding operations. Never
re-use brake fluid that has been drain-
ed from the hydraulic system. The
tank should be charged with approxi-
mately I0 to 30 pounds of air pressure.
Never exceed 50 oounds oressure.
bleeding equipment. Follow the instruc-
tions of the manufacturer when instal-
ling the adapter.
3. Loosen the primary and sec-
ondary tube nuts at the master cylinder
and bleed the master cylinder until
the fluid flow is free of air bubbles,
then tighten the tube nuts to the spec-
ified torque. Refer to Figs. 20 and 2 1,
Part 2-2. Do not overtighten the nuts.
4. If the rear wheel cylinders,
secondary brake system, are to be bled,
position a 318 inch box wrench (Fig. 9)
on the bleeder fitting on the right
rear brake wheel cylinder. Attach a
bleeder tube to the bleeder fitting. The
end of the tube should fit snugly a-
round the bleeder fitting.
5. Open the valve on the bleeder
tank to admit pressurized brake fluid
to the master cylinder reservoir.
6. Submerge the free end of the
tube in a container partially filled with
clean brake fluid, and loosen the bleed-
er fitting.
7. When air bubbles cease to ap-
pear in the fluid at the submerged end
of the bleeder tube, close the bleeder
fitting and remove the tube.
8. Repeat steps 3 through 7 at the
left rear wheel cylinder.
9. If the vehicle is equipped with
disc brakes, repeat steps 4 through
7.
starting at the right front disc caliper
and ending at the left front disc cal-
iper.
10. I f the vehicle contains drum-
type front brakes and the primary
(front) brake system is to be bled, re-
peat steps 4 through 7, starting at the
right front wheel cylinder and ending
at the left wheel cylinder.
I. Clean all dirt from the master
I I. When the bleeding operation
cylinder reservoir cover.
is completed, close the bleeder tank
valve and remove the tank hose from
2. Remove the master cylinder re-
the adapter fitting.
servoir cover and rubber gasket, and
12. On disc brake equipped vehi-
f i l l the master cylinder reservoir with
cles. be sure that the front brake pis-
the specified brake fluid. Install the tons are returned to their normal &si-
pressure bleeder adapter tool to the tions and that the shoe and lining
master cylinder, and attach the bleeder assemblies are properly seated by de-
tank hose to the fitting on the adapter. pressing the brake pedal several times
Master cylinder pressure bleeder until normal pedal travel is obtained.
adapter tools can be obtained from 13. Remove the Pressure Bleeder
the various manufacturers of pressure Adapter Tool. Fill the master cylinder
3 C L E A N I N G A N D INSPECTION
DISC (FRONT) BRAKES
thinnest section of the shoe and lining.
If the assembly has worn to a thick-
I. Remove the wheel and tire and ness of 0.230 inch (shoe and lining
the shoe and lining assemblies as out- together) or 0.030 inch (lining material
lined in Part 2-2, Section 2.
only) at the thinnest point or i f the
2. Make
a thickness measure- brake lining shows evidence of brake
ment with a micrometer across ihe fluid contamination, replace all four
reservoirs to within 114 inch from the
top. lnstall the master cylinder cover
and gasket. Be sure the diaphragm-
type gasket is properly positioned in
the master cylinder cover.
14. Centralize the pressure dif-
ferential valve as follows:
CENTRALIZING T H E
PRESSURE Dl FFERENTIAL
VALVE
After a failure of the primary
(front brake) or secondary (rear
brake) system has been repaired
and bled, the dual-brake warning
light will usually continue to be il-
luminated due to the pressure dif-
ferential valve remaining in an off-
center position.
To centralize the pressure differ-
ential valve and turn off the warning
light after a repair operation, a presl
sure differential or unbalance con-
dition must be created in the opposite
brake system from the one that was
repaired and bled last.
I. Turn the ignition switch to the
ACC or O N position. Loosen the dif-
ferential valve assembly brake tube
nut at the outlet port on the opposite
side of the brake system that was
repaired and/or bled last. Depress
the brake pedal slowly to build line
pressure until the pressure differential
valve is moved to a centralized posi-
tion and the brake warning light
goes out; then, immediately tighten
the outlet port tube nut to the speci-
fied torque. Refer to Fig. 18 and 19.
2. Check the fluid level in the
master cylinder reservoirs and f i l l
them to within 114 inch of the top
with the specified brake fluid. i f
necessary.
3. Turn the ignition switch to the
O F F position.
4. Before driving the vehicle, check
the operation of the brakes and be
sure that a firm pedal is obtained.
shoe and lining assemblies on both
front wheels.
3. Check the caliper to spindle
attaching bolt and torque. Tighten
them to the specified torque, i f re-
quired.
4. To check rotor runout, first