Chevrolet Cobalt Service & Repair Manual: Inspection
Inspect components for damage
or wear. Inspect wheel cylinder boots for tears, cuts or heat damage. Replace
as required. |
Remove wheel cylinder links. If
fluid spills from boot center hole, replace wheel cylinder. |
Brake Drums
Any time the brake drums are removed
for brake service, the braking surface diameter should be inspected with
suitable brake drum micrometer at several points to determine if they are
within the safe oversize limit stamped on the brake drum outer surface.
If the braking surface diameter exceeds specifications, the drum must be
replaced. If the braking surface diameter is within specifications, drums
should be cleaned and inspected for cracks, scores, deep grooves, taper,
out-of-round and heat spotting. If drums are cracked or heat spotted, they
must be replaced. Minor scores should be removed with sandpaper. Grooves
and large scores can only be removed by machining with special equipment,
as long as the braking surface is within specifications stamped on brake
drum outer surface. Any brake drum sufficiently out-of-round to cause vehicle
vibration or noise while braking or showing taper should also be machined,
removing only enough stock to true up the brake drum. |
After a brake drum is machined,
wipe the braking surface diameter with a denatured alcohol soaked cloth.
If one brake drum is machined, the other should also be machined to the
same diameter to maintain equal braking forces. |
Brake Linings & Springs
Inspect brake linings for excessive
wear, damage, oil, grease or brake fluid contamination. If any of the these
conditions exists, brake linings should be replaced. Do not attempt to replace
only one set of brake shoes; they should be replaced as an axle set only
to maintain equal braking forces. Examine brake shoe webbing, hold-down
and return springs for signs of overheating indicated by a slight blue color.
If any component exhibits overheating signs, replace hold-down and return
springs with new ones. Overheated springs lose their pull and could cause
brake linings to wear out prematurely. Inspect springs for sags, bends and
external damage and replace as required. |
Inspect hold-down retainers and
pins for bends, rust and corrosion. If any of these are found, replace as
required. |
Backing Plate
Inspect backing plate shoe contact
surface for grooves that may restrict shoe movement and cannot be removed
by lightly sanding with emery cloth or other suitable abrasive. If backing
plate exhibits these condition, it should be replaced. Also inspect for
signs of cracks, warpage and excessive rust, indicating need for replacement.
Inspect backing plate for evidence of axle seal leakage. Inspect backing
plate mounting bolts and ensure they are tight. |
Adjuster Mechanism
Inspect components for rust, corrosion,
bends and fatigue. Replace as required. On adjuster mechanism equipped
with adjuster cable, inspect cable for kinks, fraying or elongation
of eyelet and replace as required. |
Parking Brake Cable
Inspect parking brake cable end
for kinks, fraying and elongation and replace as required. Use a small hose
clamp to compress clamp where it enters backing plate to remove it. |
Removal
1.
Raise and support rear of vehicle,
then remove tire and wheel assembly.
2.
Mark drum and axle hub, then remove
brake dr ...
When working on or around brake
assemblies, care must be taken to prevent breathing asbestos dust, as many
manufacturers incorporate asbestos fibers in the production of brake linings. ...
See also:
Chevrolet Cobalt Service & Repair Manual. Lube, Oil & Filter, Replace
Caution: Prolonged and repeated
contact with engine oil and grease will result in removal of natural oils
from skin, leading to dryness, irritation and dermatitis. In addition, used
engine oil and grease contains potentially harmful contaminants which may
cause skin cancer. Pr ...