Method of servicing an electro-dynamic apparatus

A maintenance service for a traction motor of a locomotive, the maintenance service comprising:

• providing a spraying device for delivering a spray of a sealing material from a nozzle;
• inserting the nozzle into an access opening in the traction motor without removing the traction motor from the locomotive;
• and
• directing the spray of sealing material from the nozzle onto a surface of electrical insulation of a stator conductor element in an interior of the traction motor.

A maintenance service for an alternator of a locomotive, the maintenance service comprising:

• providing a spraying device for delivering a spray of a sealing material from a nozzle;
• inserting the nozzle into an access opening in the alternator without removing the alternator from the locomotive;
• and
• directing the spray of sealing material from the nozzle onto a surface of electrical insulation of a conductor element in an interior of the alternator.