Armatures, rotors, stators, and windings.

TM 38-260

(2) Armatures, rotors, stators, and windings. The rotors and stators of AC motors and the armatures and field

windings of DC motors are coated with varnish. This varnish serves to protect these parts from rust and corrosion. If

inspection shows that the varnish coating has deteriorated, it shall be replaced by recoating the affected parts. Only a

high grade insulating varnish approved for motor maintenance is to be used. Prior to the application of the varnish, the

parts to be protected should first have a resistance test performed. If the test shows the presence of any moisture,

affected parts must be thoroughly dried before coating with the varnish. Testing and coating with varnish should be

performed by experienced electrical maintenance personnel.

(3) Commutators and brushes. When commutators are accessible, lift brushes and completely wrap the

commutator with barrier material conforming to MIL-B-121 grade A. Release the brushes and allow them to rest on

barrier material. An alternate method is to disengage the brushes from brush holders and secure them in such a manner

that they will not come in contact with the commutator.

(4) Motor shaft. Preserve all bare metal surfaces of motor shafts with preservative compound P-2, grade 2, of

NOTE

WHEN PRESERVING MOTOR SHAFTS, PLACE A PROTECTIVE COVER OVER THE

MOTOR WINDINGS TO PROTECT THEM FROM THE PRESERVATIVE.

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