Hey,
I have a K 325 Hudson and a 302 Atlantic with a similar problem, the armature (sp?) seems to freeze up/get jammed. I can temporarily free it up by spinning it in the opposite direction by hand but it just happens again. Anyone know what the problem is and how to fix it? Any help would be greatly appreciated. Thanks! [tup]
If the motor is still in the engine, you might have a problem in the gearing. If the motor is not installed, I would check the brushes and also check for a foreign object between the armature and the field magnet.
Good Luck…
Earl
If the armature freezes, does it un-freeze when you change directions electrically? There is a thrust washer that is critical that lies on the drive shaft. It looks like a wave type washer, it is placed at the front of the motor drive shaft just before the first bearing. I suspect this may be missing.
Both the above are correct. I would bet the side linkage may be getting into a bind. One of the first things I do when I have the issue you are talking about is remove the linkage and see how it runs, and let it run for several minutes to ensure it is not a fluke. When reinstalling linkage, particulary the more involved linkage I’ve used pictures like on ebay to see how the linkage is configured. I had a 350 that gave me fits till I discovered one of the hinge rivits was sloppy and would allow just enough side movement to misalign and jam.
Keep us posted
Jim
Thanks…When it freezes I need to free it up with the hand. I’m not all that experienced with working on these things so I’ll see if I can go in and figure it out with the help you’ve given me. One (possibly stupid) question; I have some spare brushes, do different engines use different sized brushed or are they all generally the same? I have some parts left over that my dad bought at shows probably about 10 yrs ago…he’s since passed and now I’m just seeing what I can do with these engines.
The brushes should slide up in down freely in the armature plate with no side-to-side or rocking motion. If they meet that criteria and are not worn excessively, they should be fine.
Give the commutator and brush holders a thorough cleaning with contact cleaner and either an erasor or dremel rotary wire brush when you disasseble the motor. Dress the brushes with fine sandpaper on the surface that contacts the commutator.
Good Luck…
Earl
Ok. So, I just took the engine apart. I had it so the armature was going into the gears with the rest of the motor off to the side and was moving the armature with my fingers. I found that the armature never got to a point where it was stuck as when the whole motor was together but it was tougher to move at certain points. Does this suggest a gear problem?
There will never be 100% even pressure on the armature. However, I would remove the siderods and see if it smooths out. Also examine the commutator plade to make sure it is intact and look at the face of the brushes to make sure they are smooth and not catching on any protrusion from the commutator plate.
You will need to give the commutator, brush holders, and brushes a very thorough cleaning before reassembly. Spray contact cleaner on the surfaces to get them clean. Then use a pencil eraser on the commutator plate to polish the surface and remove any excess black material. You can use a cotton que-tip dipped in alcohol to clean the brush holders.
Good Luck…
Earl
I’m still leaning twards a linkage issue, particullarly since there is a pattern to the binding. If the loco is a smoker be sure and check the air cylinder / piston is clean, and the air oriface to the smoke chamber is clear. This may cause resistance and binding as well.
Jim
Ok. Good news. It seems the issue was the side rods. After taking the engine completly apart (including the side rods this time [banghead]) I noticed the armature and rear drive wheels spun very smoothly. This afternoon I put it all back together and it ran. It was sluggish at first…but then it really started running well until the rod on one side came undone…guess I shoulda tightened them a bit more. That’s the K 325…next to the 302…woot.
Good job[bow]