I just took a quick look at one of mine, although any repair would likely require a pretty thorough disassembly of the chassis. All I could see was that the bearings are square, and I was unable to detect a retaining flange on the outer surface - many loco bearings fit into a slot in the frame, with a flange on both sides of the bearing to keep it in place, while others have a shallow blind hole in the top surface of the bearing which mates with a small protrusion projecting from the upper surface of the bearing slot. You can replicate either, but dissassembly of the loco will allow you to see which method is preferable. It may also suggest another method, depending on the actual way that the other bearings are held in place. In any event, remove the driver(s) from the loco to do this work. To make the mating pin and hole, drill a hole in the upper surface of the bearing slot, sized appropriately to the thickness of the material, and using a bit that will allow you to press fit a short length of music wire in place. Drill a corresponding shallow hole (just a bit deeper than the length of the protruding music wire) and several drill sizes larger than the wire, into the top surface of the brass bearing, then re-assemble the loco.
For the other method, also requiring disassembly, cut two squares, or punch two circles, of .005" brass shimstock slightly larger than the side area of the bearing. Punch a hole in the centre of each slightly larger than the diameter of the axle, then using a utility knife and working on a hard surface, cut (by pressing down firmly, not slicing) a section out of each, making the centre hole into a "U", open at one edge. This edge will be the "bottom" - slip one of these pieces over the axle and mark it where it's even with the lower edge of the bearing, then slice off this excess material. Repeat for the other piece, then solder them to each side of the bearing. Clean up any excess solder with a file, then re-assemble the loco.
Neither of these methods is too difficult, but you need the proper tools and the confidence to do the disassembly - make notes and diagrams as required, so that you can put everything back together properly. In my opinion, this is not a job for a beginner, but if you work carefully, you can learn a lot over the course of this repair. Good luck.
Wayne
Dr. Frankendiesel aka Scott Running BearSpace Mouse for president!15 year veteran fire fighterCollector of Apple //e'sRunning Bear EnterprisesHistory Channel Club life member.beatus homo qui invenit sapientiam
- Luke
Modeling the Southern Pacific in the 1960's-1980's
The cracked axle bearing was replaced. The problem is that the axle bearing won't fit. How can I fix this?