(5) Using a pair of snap ring pliers, remove
considered too thin to last until next regular overhaul.
second snap ring (1) from pump shaft. (Not required if
(3) Replace springs if kinked, bent, or
brake only is to be removed.)
damaged.
(6) Using an allen wrench, remove three
(4) Replace brake back plate assembly if bent
screws (6). Discard screws.
or if actuation arm is bent or will not operate smoothly.
Note:
Observe position of back plate to pump
7-10.
Assembly
for use during reassembly. Suggest
marking location of brake actuation on
Assemble brake assembly to pump assembly using
pump body with grease pencil.
(7) Remove brake back plate assembly (7)
a. Using three new screws (6) and an allen
from pump assembly (8).
wrench, attach brake back plate assembly (7) to pump
assembly (8). Position back plate assembly such that
7-9. Cleaning, Inspection, and Repair
actuation arm is in line with the word AGAVENCO on
pump body (between pump foot and outlet port). Secure
screws handtight.
WARNING
b. Place brake shoes (4) ) together with the flat
Avoid breathing dust found within
ends facing each other. Holding brake shoes together,
brake assembly. Material worn off
install brake shoes to stud on back plate assembly. Fit
brake lining may be injurious to
flat ends of brake shoes on each side of actuation arm
lungs.
shaft of brake plate assembly. Install brake springs (5) to
a. Clean brake drum, shoes, and back plate
secure brake shoes in position on back plate assembly.
assembly carefully to remove dust. Do not clean brake
c. Using snap ring pliers, install snap ring (1) in
linings with oil-base cleaning fluids.
inner groove of pump shaft.
b. Inspect condition of all components, and
d. Insert woodruff key (3) into recess in pump
replace any part not found to be usable. Make the
shaft.
following specific checks:
e. Install brake drum (2) over pump shaft,
(1) Check interior of brake drum for
woodruff key, and brake shoes.
scratches, grooves, or distortion.
f.
Test fit of brake drum by spinning brake drum
(2) Check brake shoes for condition of lining.
with brake shoes in relaxed position. If any brake drag
Thickness of lining should be 1/16 inch minimum.
occurs, operate brake by hand and rotate brake drum by
(3) Check springs for condition and tension.
hand. Relieve pressure on brake lever and continue to
(4) Check brake back plate for flatness and
rotate brake drum. If brake still drags remove brake
for condition of actuation arm. Arm should rotate freely
drum and lightly file brake shoe lining to remove any high
in back plate.
spots. Replace brake drum and again check for
c. Repair or replace components as required,
rotational freedom. Repeat these steps as required until
noting the following:
brake drum spins freely with no evidence of drag.
(1) Remove light scratches from interior of
g. Secure brake assembly with snap ring (1) in
brake drum by smoothing out with crocus cloth per
outer groove of pump shaft.
Federal Specification P-C-451. Polish in direction of
drum rotation only, never across drum.
(2) Replace brake shoes if lining is
Section III. PUMP ASSEMBLY
7-11.
General
The pump portion of the pump and brake assembly (19,
7-13.
Disassembly
fig. 4-9) is a
centrifugal type, driven by
the synchromatic
windmill assembly. Pump speed depends upon the
windmill fan blade angle and helicopter forward flight
Disassemble pump assembly using figure 7-3 and the
speed. The pump is stopped and started by the brake
following steps as guides:
a. Remove screws (1) and washers (2) securing
lever (16, fig. 4-10) on the manual control panel.
inlet (3) to case (21). Remove inlet and gasket (4). (Not
required unless gasket is leaking.)
7-12.
Removal
Remove pump and brake assembly from tank installation
7-5