Hydraulic Brake System Bleeding (When To Bleed); Hydraulic Brake System Flushing - GMC chervolet camaro 1999 Service Manual

Brakes
7. Open the .brake caliper bleed screw at least% of
a tum and allow the brake fluid flow to continue
until no air is seen in the brake fluid. Apply
intermittent pressure to the brake pedal while
pressure bleeding.
Notice:
Refer to Fastener Notice in Cautions and
Notices.
8. Close the brake caliper bleed screw.
Tighten
Tighten the brake caliper bleed screw to
12 N-m (106 lb in).
9. Repeat steps 6 through 8 until all of the calipers
have been bled.
10.
Lower the vehicle.
11. Test drive the vehicle, checking for brake pedal
for sponginess or softness. Ensure that vehicle
exceeds 5 km/h (3 mph) for ABS modulator
actuation (self-test) which will purge any air from
the secondary circuit of the modulator. If after
ABS modulator actuation the pedal is still soft or
spongy, then reb!eed entire system.
12.
Remove the brake bleeding equipment from the
master cylinder.
Hydraulic Brakes 5-47
Hydraulic Brake System Bleeding
(When To Bleed)
A bleeding operation is necessary to remove air when
it is introduced into the hydraulic brake system.
It may be necessary to bleed the hydraulic system at
all four corners if air has been introduced through
low fluid level or by disconnecting brake pipes at the
master cylinder. If a brake hose is disconnected at one
wheel, only that wheel caliper needs to be bled: IJ
brake pipes or hoses are disconnected at any fitting
located between master cylinder and brakes, then the
brake system served by the disconnected pipe or
hose must be bled.
Hydraulic Brake System Flushing
The entire hydraulic brake system sho~ld_ be .
thoroughly flushed with clean brake fluid 1f there 1s. any
doubt as to the grade of the fluid in the systei:n or 1f .
the fluid used contains the slightest trace of mineral 011.
All rubber parts which have been subjected to .
contaminated fluid must be replaced before flushing
the system.
Flushing is performed at each wheel similarly to
bleeding. The new fluid must be forced throu~h the
system until it emerges clear in color. Approximately
one quart of new fluid is needed to flush the system.
After completing the flushing operation at all of
the bleeder valves check that the master cylinder is
filled to the correct level.