Wheel Brake Reassembly And Installation; Brake Lining Installation; Brake System Bleeding; Brake Lining Conditioning - Cessna 177 SERIES Service Manual

When new anchor bolts are to be installed, press out
punch until lining is firmly against back plate.
old bolts and install new bolts with a soft mallet. g.
Realign the lining on the back plate and install
f. Inspect wheel brake disc for a minimum thick-
and set rivets in the remaining holes.
ness of 0.190 inch. If brake disc is below minimum h. Install a new lining on pressure plate in the same
thickness, install a new part. manner.
i. Position pressure plate on anchor bolts and place
5-55. WHEEL BRAKE REASSEMBLY. (Refer to figure cylinder in position so that anchor bolts slide into the
5-4.) torque plate.
j. Install back plate with bolts and washers.
NOTE
5-59. BRAKE SYSTEM BLEEDING.
Lubricate parts with clean hydraulic fluid
during brake assembly.
NOTE
a. Refer to figure 5-4 as a guide while reassembling
Bleeding with a clean hydraulic pressure
wheel brakes.
source connected-to the wheel cylinder
bleeder is recommended.
5-56. WHEEL BRAKE INSTALLATION.
a. Place brake assembly in position with pressure
a. Remove brake master cylinder filler plug and
plate in place.
screw flexible hose with appropriate fitting into the
b. Install back plate.
filler hole at top of the master cylinder.
b. Immerse opposite end of flexible hose in a con-
NOTE tainer with enough hydraulic fluid to cover end of
hose.
If torque plate was removed, install as c. Connect a clean hydraulic pressure source, such
the axle is installed, or install on axle.
as a hydraulic hand pump or Hydro-Fill unit, to the
If the brake disc was removed, install
bleeder valve in the wheel cylinder.
as wheel is assembled.
d. As fluid is pumped into the system, observe the
immersed end of the hose at the master brake cylinder
5-57.
CHECKING BRAKE LINING WEAR. New brake for evidence of air bubbles being forced from the
lining should be installed when the existing lining has brake system. When bubbling has ceased remove
worn to a minimum thickness of 3/32 inch. A 3/32 bleeder source from wheel cylinder, and tighten the
inch thick strip of material held adjacent to each lin-
bleeder valve.
ing can be used to determine amount of wear. The
e. Remove flexible hose from master brake cylinder
shank end of a drill bit of the correct size can also
and install filler plug.
be used to determine wear of break linings.
5-63. BRAKE LINING CONDITIONING. The brake
5-58. BRAKE LINING INSTALLATION. (Refer to lining pads used in this assembly are either non-asbestos
figure 5-4.)
organic composition or iron based metallic composition.
a. Remove bolts securing back plate, and remove Brake pads must be properly conditioned (glazed) before
back plate.
use in order to provide optimum service life. This is ac-
b. Pull brake cylinder out of torque plate and slide complished by a brake burn-in. Burn-in also wears off
pressure plate off anchor bolts.
brake high spots prior to operational use. If brake use is
c. Place back plate on a table with lining side down required before burn-in, use breaks intermittently at
flat. Center 9/64 inch (or slightly smaller) punch in LOW taxi speeds.
the rolled rivet. Hit the punch sharply with a ham-
mer Punch out all rivets securing the linings to the UI
back plate and pressure plate in the same manner.
Brake burn-in must be performed by a qualified
NOTE person familiar with acceleration and stop
distance of the aircraft.
A rivet setting kit, Part No. R561, is avail-
able from the Cessna Parts Distribution (CPD 2).
a. Non-asbestos Organic Composition Burn-in.
The kit consists of an anvil and punch. 1. Taxi the aircraft for 1500 feet, with engine at
1700 rpm, applying brake pedal forces as needed to
d. Clamp the flat side of the anvil in a vise.
maintain 5 to 10 M.P.H. (5 to 9 knots).
e.
Align new lining on back plate and place brake 2. Allow brakes to cool for 10 to 15 minutes.
rivet in hole with nvet head in the lining. Place the
3. Apply brakes and check to see if a high throttle
head against the anvil.
static engine runup can be held with normal pedal
f.
Center rivet setting punch on lips of rivet. force. If so, conditioning burn-in is complete.
While holding back plate down firmly against lining, 4. If static runup cannot be held, repeat Steps
hit punch with hammer to set rivet. Repeat blows on 1 thru 3 as needed.
5-22 Change