TM 11-6125-240-34
l. Insert four screws (19) through the dc endbell, sta-
must engage lead of capacitor unit (28). Refer to figure
tor housing, and ac endbell, and install four nuts (17).
g. Attach the grounded brush holders to the dc
Do not tighten.
endbell using a flat washer (32), and screw (30). Be sure
m. Be sure that outer and inner races of the bearing
that one jumper lead (fig. 4-9) is connected between the
on the dc end are locked in place. Install the load spring
pair of grounded brush holders, and the other between
and shim as follows. Refer to figure 4-10.
the pair of insulated brush holders.
(1) Stand the inverter on the fan cover with the ac
end upward.
h. Connect lead assembly (25) to grounded brush
(2) Check distance between spring and surface of
holders with two screws (24).
endbell (A, fig. 4-10) with a dial indicator. Shim as
CAUTION
Read paragraph 4-14 carefully before replac-
necessary, so that A is between 0.015 and 0.033 inch.
ing bearings. Failure to observe the specifica-
NOTE
tions, therein, may result in premature bear-
If 0.005-inch shims must be used, interleave
them between 0.015-inch shims. Do not use
ing failure. Bearings are critical items, use
more than two 0.005-inch shims, nor place
only the type specified for use on this inverter.
them directly against either the bearing or
i. Push the internal bearing plate (65) into position
on the dc end of the armature assembly (12). Apply a
the spring.
(3) Install bearing plates (39 and 40) and secure
thin film of Loctite A (manufactured by Loctite Cor-
poration, Newington, Conn., FSCM05972) to the bear-
with two screws (37) and flat washers (38).
(4) Set the inverter back on its base and remove
ings (63 and 64) into place on the armature shaft.
fan cover, pending further reassembly. Check to see
NOTE
Use minimum amount of Loctite to avoid get-
that armature rotates freely.
ting any on the seal, or inside the bearing.
n. Attach each of the short heavy brush leads from
j. Work the ac endbell assembly (43) over the bear-
the dc stator (21) to the dc brush holders (22) with a
screw (20).
ing (63). Slide the armature assembly, with bearings,
and ac endbell attached, into the stator housing (18)
p. Assemble fan spacer (11), flat key (10), fan (9),
from the ac end. Tap with a fiber mallet to seat firmly.
Attach the load assembly (50) from the ac stator, using
new key washer (8) and a new locknut (7) on dc end of
flat washer (49), lockwasher (48), and screw (47). Make
armature shaft. Tighten locknut to a torque of 150 to
sure that the lead assembly is in the notch in the stator
180 inch-pounds. Bend one or more key washer tabs
into locknut slots to lock the nut. Be sure that armature
housing.
still rotates freely.
k. Work the dc endbell assembly (23) into position
over the hearing (CM) and onto the stator housing. Tap
q. Install fan cover (3), securing with two washers
with a fiber mallet to seat firmly. Position the external
(2) and screws (1).
bearing plate (16) over the armature shaft and align
r. Install ac endbell cover (6), securing with four flat
washers (5) and screws (4).
the external hearing plate screwholes with those of the
internal hearing plate. Install four flat washers (16),
lockwashers (15), and screw (14), as shown.
4-19
