ARMY TM 9-6115-464-34
AIR FORCE TO 35C2-3-445-2
NAVY NAVFAC P-8-624-34
Do not allow solvent to contact brushes. Failure to observe this caution could result in
(5) Clean brushes with a clean, lint-free cloth.
(6) Inspect housings and frames for cracks, corrosion, and distortion. Replace defective parts.
(7) Inspect bushings for wear, galling, and scores. Replace defective parts.
(8) Test armature for grounding as follows:
(a) Connect one lead of a test light to the armature core.
(b) Touch the other test lead to each commutator riser.
(c) If test light glows, armature is grounded and must be replaced.
(9) Test armature for short circuits as follows:
(a) Place armature on a growler fixture.
(b) Activate the fixture and slowly rotate armature while touching armature lightly with a steel strip.
(c) Strip will vibrate against armature over a shorted area.
(d) Replace armature if a short is indicated.
(10) Turn down armature if scored or out of round. Undercut mica to a depth of 0.025 to 0.032 inch below
surface of commutator. Use care to avoid widening commutator slots.
Check diameter of commutator after removing material. Diameter shall not be less than
(11) Use an ohmmeter to check field coils for insulation breakdown as follows:
(a) Attach one lead to field housing and the other lead to field coil terminal.
(b) Replace field coil if a reading of less than 1 megohm is indicated.
(12) Inspect drive assembly for badly worn or broken teeth. Check internal spline for wear and damage.
Check spring for cracks, breaks, and distortion. Replace drive assembly if defective.
(13) Inspect brushholders and support for cracks, corrosion, and other damage. Replace defective parts.
(14) Measure brush length. Replace brushes if length is 5/16 inch or less.
(15) Test brush spring tension with a spring tester. Tension shall be 36 ounces to 40 ounces. Replace
brush springs if tension is less than specified.
(16) Inspect all threaded parts for crossed, stripped or peened threads. Replace damaged parts.
(17) Using an ohmmeter, test for continuity across terminals of solenoid frame assembly. There shall be
no sign of open circuit.
(18) Check solenoid frame assembly for grounding by touching one lead of ohmmeter to either lead and
the other to the frame casing. There shall be no sign of continuity.
(19) Smooth scratches, burrs, and nicks on any machined surfaces using a fine file. Remove all filings