253 engine armature removal

An easy way to get the gear off but will need new gear to replace is cut it off with a dremel .

Thanks. So I would just find a replacement gear and slip it on the armature shaft? How would I "cement" it there--with JB Weld?

Unless the armature is shot, you probably don't "need" to remove it. You should be able to clean dirt grease etc in place.  There are small gear pullers made for the purpose though. 

Lionel says that, once pulled of the shaft, pinions are not reusable. I have never thought about reusing them with Locktite.   Many pinion replacements are available, so reusing one has to come up.  Removing a pinion from a real railway motor can also be a problem. We used pullers which pulled in the inboard side of every tooth.  Pulled with grade 8 studs, sometimes as many as one between every tooth. Torqued the stude to the max values and then hit the plate over the end of the shaft with sledge hammer.  It lets go with a big bang.  

 I have removed many pinion gears, particularly on prewar motors. As mentioned above I use a Dremel tool and grind them down and then they break right off. I order replacements from Jeff at Train Tender . I have rigged a fitting for my drill press that allows me to use a drill press like an arbor to push the new gear in place. In 90 percent of the cases the new gear  is tight enough that it will not slip. However if I notice any slippage I will remove it. If it slips it is easy to remove and I will put a drop of JB Weld on the interior of the pinion gear before reinstalling it. 

Jim

Also you can knurl or upset the shaft at the point the armature sits with a small flat chisel to raise some "notches" to hold the pinion gear. An arbor press or a Lionel press eases placement as you can slowly press pinion gear into correct position. Also heating the gear on a hot plate if it is an extremely tight fit can help and use this for bearing placement on shafts