Housing frame assembly
Carbon brush assembly
(2) Clean all non-electrical part by immersing in dry cleaning solvent (fed. spec. P-D-680). Wipe thoroughly and
allow to dry.
(3) Inspect the fan assemblies for bent or damaged parts. Replace defective fan assemblies.
(4) Inspec t the motor brushes for cracks, chips, wear, or scoring. Replace worn brushes.
Brushes in the combustion motor are designed to last a minimum of 2,000 hours in
operation before replacement.
(5) Inspect the commutator. Replace the armature and bearings if the commutator is scored or badly burned.
Light scoring can be cleaned up with fine sandpaper.
(6) Inspect the suppression capacitors (condensers) for any signs of damage. Replace if damaged. Use a
capacitance tester to check the capacitors. Capacitance should be 0.47 microfarad ±10%. If not, replace the capacitors.
(7) Connect the brown and white leads from the capacitors to the terminal strip as shown on the wiring diagram.
Restore power and test the motor.
c. Assembly. Assemble the combustion motor by reversing disassembly sequence. Note the following:
(1) If a new field (21, fig. 8-2) is being installed, carefully inspect the wires (6 and 10) secured to the field winding.
The wires supplied with replacement fields are covered with neoprene insulation, which is not acceptable for this
application. Cut off the wires and splice on nylon-insulated wires of the correct length.