I have 2 Atlas B23-7s and 1 Atlas GP38. They are lighter weight than the old Atlas and Atlas/Kato locomotives and do not have as much pulling power. Has anyone added weight to these locomotives, and how did you do it?
I have had similar problems with this due to the lighter, less expensive metal Atlas uses for its frames. There really is no way a large amount of weight can be added to significantly improve pulling power since most of the shell is taken up by the mechanism. You can try packing lead into some corners of the inside of the shell.