Lionel Postwar Armature

I use CRC 2-26 soaked q-tips to clean the armatures, brush holders and such. That could clean up any misplaced lubricant and clean the surfaces.

It wouldn't be unheard of for the locomotive to benefit from new brushes and possibly new brush springs. They are readily available from most parts suppliers.

Looks to me like uneven brush wear. A new set wouldn't hurt in any case.

Just carbon from the brushes. Normal.

I suspected that it's carbon leeching from the brushes. I have an order outstanding for replacement brushes. Hope it solves the issue. 

While you have it apart, clean the brush wells, too, and check the springs. 

Honestly if the loco runs well now and doesn't make a loud squawking sound, I wouldn't be concerned about the black line.  If it runs well, trying to repair it may do more harm than good.  Some replacement brushes have been found to be so out-of-spec that they are unusable.  Brush spring tension has been called "the blackest of the black arts."  And depending on your repair skills it's quite easy to introduce new problems during disassembly / assembly.  Enjoy what you have!

Thank you.  Right on cue the squawking sound started in the evening yesterday. It appears that the brushes will need replacement. Hoping for the best.

Sounds like an armature lube issue to me.

Thank you.  Right on cue the squawking sound started in the evening yesterday. It appears that the brushes will need replacement. Hoping for the best.

Brushes don't usually squawk.
It is usually caused by dry armature bearings.
If you started out with very dry bearings, it may take several light applications of lubricant.
I use light oil on the gear end because the bearing is sintered on that end.
Many Lionel Steam engines do not have a metal bearing on the brushplate end.
When the armature shaft just rides in an unbushed hole through the fiberboard brushplate, I use Labelle 106 grease, being careful to coat the inside of the hole with a toothpick, plus a light coat on the armature shaft.

If the hole has a metal bushing, then I use light oil.

Thanks, will lube the armature shaft first and see how that goes. I took out the motor to take a look this morning and the brushes appear to be replacement brushes, not the copper colored originals. But I wont change them if not necessary, especially if some of the carbon ring on the armature is normal.

@JMat What C.W. said is important.  If the hole in your brushplate is worn wide from a lack of lubrication, you'll have to add some almost every operating session.  That lube will end up on the armature's commutator.

If this is the case with your loco, what you really need is a new brush plate, or a brass bushing properly sized for this purpose, that will fill in the widened hole and keep a thin film of oil around the shaft.

@C W Burfle who sells these bushings for a 675 or 224 type loco?

@C W Burfle who sells these bushings for a 675 or 224 type loco?

Don't know.
I've read that some folks use eyelets.
If someone posts a source, I will save it.
I'd probably just replace the brush plate.

Hello J! You and I are both newbies to OGR repairs, I but a few months more practiced perhaps.  When I read your posts it resonated like echoes of my own learning process.

The good people who have commented know their stuff. Take advantage of their collective wisdom. And if I may add my own two cents, I would try to keep the brushes I have. If they are merely dirty and show no signs of wear, then use the CRC and cotton cloth and abraid with a non metallic scrubber like Scotch Brite. A pair of new springs would cost 50 cents plus shipping, to keep the tension right on the commutator.

As far as the black lines on the commutator are concerned, I submit that you need to know the cause before you seize upon a solution. If it is a mechanical imperfection from worn brushes, then replacing the brushes  solves the cause, not the effect. The commutator's face is still blacklined. I believe , because these smart people told me, that a few black lines are normal. Whether or not this is some electrolytic "tattoo" of the armature, it doesn't much matter, since it isn't surface grime and has no adverse effect upon conduction.

If the imperfection bothers you, remind me some time to tell you about Nathaniel Hawthorne's short story about the impossibility of perfection in reality.

All the best!

Thanks for the replies everyone. My untrained eyes don't see any gaps on either end of the armature shaft (brush plate or other side). Will post a pic later to show what it looks like. 

You aren't likely to see any gaps. You might be able to feel the shaft wiggle from side to side.

Finally got around to disassembling the engine. Here are pics of the armature attached and with the brushplate removed. 

In your assembled picture, I can see the slot at the top of the brush on one side, but not on the other.
The slot should be facing the top, with the spring sitting in it.
Did you have one brush upside down, or is the pair mismatched?

Yes, mismatched and very worn brushes. I've replaced them. Unfortunately I've severed one of the yellow wires. Now need to figure on how to reattach that 😡

Did you just break off the end?
If so, maybe there is enough slack to just re-attach it.
Hint: Lionel used "pushback" insulation wire there and many other places. You don't strip it. You just slide the insulation back.

If the wire is too short, the easy answer is to splice a piece onto the end.

When I hit similar problems, I replace the whole wire, but that involves removing the e-unit, and taking it apart to get to the contacts to unsolder the old wire and solder in a new one.
I suggest not going there yet. It is tedious, and can be a PIA.

Here is what it looks like now with the wire snapped off

Bummer.  I don't think there is any way around disassembling the e-unit to solder a new wire in place.

Unless you have a fine point soldering pencil and very skilled, like CW said, the whole reversing unit is going to have to be dissembled to repair the broken wire at the finger assembly.

Sigh... Does the snapped wire fit into the open hole/slot next to the yellow wire that is not snapped? 

That won't work, needs to go in the end one. PITA

By the way, the soldering job on the power terminal of your e-unit looks a little sloppy. I'd clean that up while I was working on it. I use solder wick to remove excess solder.