A method for resin coating electrical windings enclosed within a housing of an electric motor and defining a central cylindrical cavity, the method including preparing a core having an elastic wall that encloses an inner chamber having an opening provided with a selective shut-off means, as well as a lower disc-like portion and an upper cylindrical portion that protrudes from a surface of the lower portion, coupling the core and an electric motor stator, in such a way that the upper portion occupies the cavity of the stator, and the lower portion is positioned within a housing of the motor below the electric windings, inflating the inner chamber through the opening, in such a way that the lower portion comes into contact with an inner surface of the housing and the upper portion comes into contact with the windings, which define a central cavity of the stator, pouring a resin so that it coats the windings when they are not in contact with the core; deflating through the opening the inner chamber, and separating the core from the stator, whose windings are coated with resin.