lionel 2023 troubleshooting

[northernpike]

Need some advice on my postwar alco 2023.  The engine is stuck in neutral.  First though was e unit.  I checked that over.  The pawl moves up and down fine when direction is activated on the 1033.  Drum looks good, fingers are clean and still look new.  I think it is something else.  All solder points look good and clean.  No broken wires.  Brushes look new, springs good.  I did not take off brushplate to check commutator.  Where should I look next?

Thanks much in advance.

Tom

[lionelsoni]

You're looking in the right places.  If the drum is turning, you're not in neutral.  Something is open in the motor circuit.  There should be a connection from the pickup to a terminal on the e-unit.  That's okay if the pawl is moving.  The same terminal should have a short wire to one of the fingers.  That wire could be open; or the finger might not be making contact with the drum.  There's a green wire soldered to the finger at the other end of the row of 4 fingers that goes to the field terminal.  That wire might be open; or its finger might not be making contact.  You've probably checked the yellow and blue wires from the e-unit to the brushes.  Those fingers are probably okay, since you would have had some motion even if one of them was lifted.  Another possibility is that the field coil has lost its connection to the motor frame, or the motor frame to the locomotive frame.

[cwburfle]

Occasionally, the wires from the e-unit that are soldered to the brush holders or the field coil terminal will appear to be connected, but will not actually be transfering electricity. When this happens, the exposed wire will often look green (but not always). You may need to trim the ends of those wires a bit, and resolder them in place.  I have also run into instances where the brush holders needed an extra careful cleaning. In this case, power is going to the brush holder, but not from the brush holder to the brush. Same goes for the contact between the e-unit drum and the contact fingers. None of these issues are common, but they do happen.
In the case of the e-unit, my fix is to remove the 2 finger contact and drum, and carefully clean them (the four finger assembly should be cleaned too, I don't find it necessary to remove it for cleaning). I use a fiberglass burnishing tool, followed by some mineral spirits or Caig Contact cleaner to remove the debris. Some folks swear by spray contact cleaners.

 

[bfskinner]

cwburfle

Quoted in part only

In the case of the e-unit, my fix is to remove the 2 finger contact and drum, and carefully clean them (the four finger assembly should be cleaned too, I don't find it necessary to remove it for cleaning). I use a fiberglass burnishing tool, followed by some mineral spirits or Caig Contact cleaner to remove the debris. Some folks swear by spray contact cleaners.

Just make certain that whatever chemicals you use, spray or otherwise, are safe on plastics. I have seen several instances where the axle of the drum was swollen and tightly adhered to the side plates. It has to turn very easily and smoothly to cycle properly. I prefer a little cleaner-on-a-Qtip to a spray, but that's just me. Take care not to distort the little contact-fingers.

.

 

[cwburfle]

bfskinner

Just make certain that whatever chemicals you use, spray or otherwise, are safe on plastics.

To clarify my comment: I mentioned the spray cleaners because some guys like them. While I have a can or two around, in general I don't use them. I see no need to contaminate the air in my home with that stuff.. Using a little Mineral Spirits or Caig Contact Cleaner on a Q-tip generates a lot less fumes.
There is the plastic safe issue as well.

[northernpike]

Got it fixed.  It WAS the blue brushplate wire.  The connection looked good, but niticed the green discoloration.  Clipped it, resoldered and it runs great!  Thanks for the help!