Specifications
PART
2-1-General Brake Service 2-5
APPROXIMATELY
45"
H1300-A
FIG.
9-
Wrench for Bleeding Brake
Hydraulic System
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
114 to 112 inch from the top of
the reservoirs.
7.
If the primary (front brake)
system is to be bled, remove the front
wheel covers, and the front wheel and
tire assemblies to gain access to the
bleeder fittings on the disc brake cal-
ipers. Repeat steps 2 through 6 at
the right front disc brake caliper and
ending at the left front disc brake
caliper.
8.
Be
sure that the front brake
pistons are returned to their normal
positions and that the shoe and lining
assemblies are properly seated by
depressing the brake pedal several
times until normal pedal height exists.
Install the front wheel and tire assem-
blies on the front wheels, and torque
the mounting bolts to specification.
Install the wheel covers.
9.
Centralize the pressure dif-
ferential valve. Refer to the Centraliz-
ing the Pressure Differential Valve
Procedures which follow.
PRESSURE
BLEEDlNG
Bleed the longest lines first. The
bleeder tank should contain enough
new Rotunda Brake Fluid to complete
the bleeding operation. Use Rotunda
Brake Fluid
-
Extra Heavy Duty
-
Part Number C6AZ- 19542-A
(ESA-M6C25-A) or equivalent for all
disc brake applications and Rotunda
Brake Fluid
-
Heavy Duty
-
Part
Number
B7AZ- 19542-A, R103-A
or equivalent for power drum or
standard drum applications. The
brake fluid is colored blue for identi-
fication purposes. Do not mix low
temperature brake fluid with the
specified disc brake fluid during the
bleeding operations. Never re-use
brake fluid that has been drained
from the hydraulic system. The tank
should be charged with approxi-
mately 10 to 30 pounds of air
pressure. Never exceed 50 pounds
pressure.
1. Clean all dirt from the master
cylinder reservoir cover.
2. Remove the master cylinder res-
ervoir cover and rubber gasket, and
fill
the master cylinder reservoir with
the specified brake fluid. Install the
pressure bleeder adapter tool to the
master cylinder, and attach the
bleeder tank hose to the fitting on the
adapter.
Master cylinder pressure bleeder
adapter tools can be obtained from
the various manufacturers of pres-
sure bleeding equipment. Follow the
instructions of the manufacturer
when installing the adapter.
3. Loosen the primary and sec-
ondary tube nuts at the master cyl-
inder and bleed the master cylinder
until the fluid flow is free of air
bubbles, then tighten the tube nuts
to the specified torque. Refer to Figs.
20 and 21, Part 2-2. Do not over-
tighten the nuts.
4. If the rear wheel cylinders and
the secondary brake system is 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 around 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 bleeder 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 wheel cylinder of the secondary sys-
tem being bled.
9.
If the primary (front brake)
system is to be bled, remove the front
wheel covers, and the front wheel and
tire assemblies to gain access to the
bleeder fittings on the disc brake
calipers. Repeat steps 4 through 7,
starting at the right front disc cali-
per and ending at the left front disc
caliper.
10.
If
the vehicle contains drum-
type front brakes and the primary
(front) brake system is to be bled,
repeat steps 4 through 7, starting
at the right front wheel cylinder and
ending at the left wheel cylinder.
11. When the bleeding operation
is completed, close the bleeder tank
valve and remove the tank hose from
the adapter fitting.
12. On disc brake equipped ve-
hicles, be sure that the front brake
pistons are returned to their normal
positions and that the shoe and lining
assemblies are properly seated by
depressing the brake pedal several
times until normal pedal height is
obtained. Install the front wheel and
tire assemblies on the front wheels, and
torque the mounting bolts to specifi-
cation.
1
nstall the wheel covers.
13. Remove the Pressure Bleeder
Adapter Tool. Fill the master cylinder
reservoirs to within
114 to 112 inch
from the top.
lnstall the master cyl-
inder 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:
CENTRALlZlNG THE
PRESSURE DIFFERENTIAL
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 pres-
sure differential or unbalance con-
dition must
be
created in the opposite
brake system from the one that was
repaired and bled last.
1. Turn the ignition switch to the
ACC or ON 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. 20 and 2
I.
2. Check the fluid level in the
master cylinder reservoirs and
fill
them to within 114 to 112 inch of
the top with the specified brake fluid,
if
necessary.
3.
Turn the ignition switch to the
OFF position.
4. Before driving the vehicle, check
the operation of the brakes and
be
sure that
a
firm pedal is obtained.