THRUSH S2R – G10 - Brake Removal and Disassembly

THRUSH AIRCRAFT, INC – MODEL S2R-G10
AIRCRAFT MAINTENANCE MANUAL
6-7
I. Inflate tube until beads seat on wheel
flanges. Remove valves core and
allow tube to deflate.
J. Install valves core and inflate tires from
40 to 60 psi. Check to assure valve
stem does not leak before installing
valve cap.
K. Lubricate washer and axle nut (see
Section 2, Servicing). Install wheel
assembly on axle and secure with
washer and axle nut.
L. While manually rotating wheel, torque
axle nut to 80 inch-pounds, continue
rotating wheel and back off to zero
inch-pounds. While manually rotating
wheel, torque to 40-inch pounds. If
nut is not to locking position, advance
to next position, not to exceed 30
degrees, and install cotter pin.
M. Install hubcap and hubcap retaining
ring.
N. Install brakes back plate assembly and
torque bolts to 60 inch-pounds. These
bolts are self-locking and should be
inspected for the self-locking feature.
Replace bolts if the self-locking feature
is damaged or destroyed.
O. Wheels may be repainted if the parts
have been repaired and thoroughly
cleaned. Paint exposed areas with
one coat of zinc primer and one coat
of aluminum lacquer.
*NOTE*
Do not paint working surfaces of
the bearing cups.
BRAKE REMOVAL AND DISASSEMBLY
A. Release parking brake.
B. Jack aircraft as outlined in Section 2.
C. Disconnect and cap brake hydraulic
supply line at brake housing.
D. Remove back plate assemblies from
calipers.
E. Remove caliper assemblies.
F. Remove pressure plate assembly.
G. Clean all metal surfaces with
denatured alcohol and dry thoroughly.
All “0” rings are to be replaced.
Remove pistons by injecting air into
the caliper ports (15 to 20 psi)
maximum pressure.
USE CAUTION WHEN BLOWING
PISTONS OUT OF THE CALIPER
CYLINDERS WITH AIR, AS
PISTONS CAN FLY OUT AT HIGH
SPEED. TURN THE CALIPER
OVER SO PISTONS ARE FACING
THE WORK TABLE AND
CUSHION THEIR IMPACT WITH
RAGS. WEAR APPROPRIATE
PROTECTIVE CLOTHING AND
EYEWEAR.
WARNING!
H. Inspect brake cylinders for cracks,
nicks, corrosion and damaged threads.
Inspect inlet and outlet hydraulic ports
for foreign contaminates. Examine
cylinder walls for scoring or excessive
wear. Blend and polish light scratches
in piston cavities with fine emery cloth,
600 grit. Castings that are cracked or
have damaged threads should be
replaced.
I. Inspect anchor bolts for cracks,
corrosion, permanent set and
excessive wear. Replace bolts that
are bent, cracked or severely
corroded.
J. Inspect pistons for cracks, nicks, burrs,
or excessive wear. Remove burrs and
blend out nicks, using fine emery cloth
600 grit, and clean thoroughly.
*NOTE*
The pistons are equipped with
a friction spring (drag ring) on
the piston tail. It is
recommended that this ring
NOT be removed unless it
requires replacement.
K. Inspect pressure plate assembly for
cracks, damaged pins and excessive
warped contours. Replace pressure
plate if cracked or severely deformed.
Replace cracked or deformed pins.
Effective: 03/26/2010 Page