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More than likely, the whistle motor in the tender needs to be serviced. Take the motor apart and clean everything (brushplate, brushes, and commutator face) with Naphtha. Reassemble and add a drop of light oil to the bearings on both ends of the armature shaft.

Clean all the wheels and all the track with Naphtha also.

The KW transformer may also need its whistle rectifier disc replaced.


Larry