TM 5-4310-375-14
WARNING
Electricity is dangerous. Before performing any maintenance or adjustments,
be sure the electrical power is turned off. Never depend on the ON-OFF
switch. Turn power off at the source.
a. Removal/Disassembly. Remove the four screws (5, fig 5-1), conduit box cover and gasket (6, 7), disconnect
and tag, as necessary, all motor leads within the motor conduit box (9). Unscrew retaining nut of conduit connector (27)
and pull out conduit (29), conduit connector (27), and remove conduit washers (28) from conduit box (9). Reassemble
gasket (7), cover (6), and screws (5) to prevent loss until ready for motor disassembly. Refer to para 4-14 and remove
belt guard, drive belts and drive pulley shown in figure 4-2. Remove four locknuts (1, fig 5-1) flat washers (2), and
screws (3). Attach a lifting device to eye bolt (23) and lift motor assembly (4) off air receiver saddle and place motor
assembly on a clean work bench. Disassemble motor assembly (4) as follows:
(1) Remove four screws (5), conduit box cover (6), and cover gasket (7). If removal of conduit box (9) is
required, remove two screws (8), conduit box (9), and box gasket (10).
(2) Remove four nuts (11) and through bolts (12). Tap endplate (13) with a soft hammer, or equivalent, to
break seal against stator (26) and pull away from stator assembly (26). Remove thrust washer (14) and,
as necessary, two lubrication fittings (15).
(3) Remove key (16) from shaft keyway if not removed when drive pulley was disassembled from shaft. Tap
endplate (17) with a soft hammer, or equivalent, to break seal against stator assembly (26). Pull endplate
(17) away from stator assembly. The rotor and shaft assembly (22) and bearings (19, 20) will come out of
stator assembly along with endplate (17).
(4) Pull endplate (17) off of shaft bearing (19) and remove two bearing guards (18). Use a bearing puller and
remove pulley end bearing (19) and closed end bearing (20) from rotor and shaft assembly (22).
(5) Only when replacement is necessary, pull internal fan (21) off rotor and shaft assembly (22). It is not
necessary to remove eye bolt (23) or nameplate screws and nameplate (24, 25) from stator assembly (26),
except for replacement.
b. Repair/Replacement. Repair of the electric motor assembly is limited to replacement of defective parts, such as
the bearings (19, 20, fig 5-1). Press new bearings onto rotor and shaft assembly (22) until they seat against shoulders
on shaft extensions. Defects in windings of rotor and shaft assembly (22) or stator assembly (26) is cause for replacement
of motor assembly (4).
c. Reassembly/Installation. Reassembly and installation of electric motor assembly is in the following sequence:
(1) If removed, install eye bolt (23, fig 5-1), nameplate (25) and screws (24) on stator assembly (26). Assemble
internal fan (21) onto rotor and shaft assembly (22).
CAUTION
When pressing bearings (19, 20) into place, press on inner races only to prevent
bearing damage.
(2) Assemble closed end bearing (20) and pulley end bearing (19) onto rotor and shaft assembly (22) bearing
journals, pressing on inner races only, until bearings seat against shaft shoulders.
(3) Assemble two bearing guards (18) and endplate (17) over shaft extension and bearing (19). Carefully
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