Model Railroads/Won't run in reverse
QUESTION: I borrowed a 625 LV Switcher from a friend and promised to handle it with care. It fell off the table and now it will only operate in the forward position. I know the problem is not the switch attached to the E unit. I have cleaned all the suspect areas to no avail. I removed the armature and all the worm gears are oiled. I have noticed that I can manually turn the armature in either direction and the wheels will move accordingly. However after applying power the wheels will only go forward. After going thru the natural setting to reverse the armature will try to reverse but will only move about 1/2 inch then stop. The E unit appears to be clean and working thru all the positions. Is my armature toast? Any quick fix ideas would be appreciated by this newby enthusiast.
ANSWER: Hello Frank, Thanks for the question.
I think you are safe about the armature, it is NOT toast. I asume we are talking about a 625 Lehigh Valley 44 ton switcher circa 1957-1958. If so the unit has an on/off switch underneath. This switch is on or off for power to the reversing relay coil only. The actual E-unit is the device that determines the direction of the engine. In case you are not familiar with E-unit operation: When running the engine with the E-unit switch in the on position you can power down your track voltage and when you power up again the
E-unit will activate and this happens every time you power down and power up. The sequence of events for the engine is forward-stop-reverse- forward-etc, etc repeating.
I think that the fall has bent the little prongs on the E-unit to where they do not make connection on one or more connections of the E-unit. It looks like a small commutator and it is a very clever device. You should look very closely at the E-unit to determine if proper connection is being made.
Also I reccommend that you obtain a book from Kalmbach titled "Repair and Operating Manual for Lionel Trains 1945-1969" There is a very good article on page 181 about E-units and on page 20 about the 625 LV.
Back to the armature, if it runs forward it is good. The forward/reverse ccondition is a matter of changing the wiring so that the motor revolves one direction or the other.
I hope this message helps.
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QUESTION: Thanks for the hints Charles. I did disassemble the E unit and cleaned it up somewhat. All the "fingers" touching the drum are doing just that. The contacts don't appear to be pitted. I did take off the armature to inspect the worm gears at its base as well as the one gear it sits next to for forward/ reverse movement. All look good. I also disconnected all the wires from the e unit to the motor and then tested the motor by applying power to each direction. The reverse DID NOT work. When all wires were connected same problem...only goes forward. I did notice that when it was its turn to go in reverse the armature would move ever so slightly then bind. It looks like the armature wants to screw upwards instead of rotate smoothly on its axis. When I checked the armature I didn't have any left over parts so I believe it was replaced in exactly the same way it came out. I also tried the switch underneath. When turned to the opposite direction the car doesn't move in any direction...only the light eliminates. Boy am I stumped!
Frank you have added some inforfmation that I haave not considered. That is the binding possibility of the armature. When a motor turns in one direction the armature tends to shift within it's mounting and when the motor is reversed it shifts in the opposite direction. I am not talking about the spinning motion but about the"play" whithin the bushings. You might try to move the armature,(not spin) to see if it has excess movement which would cause it to bind and therefore not work properly.
Another thing I have found it that putting things back as you found them does not help when you find that the person before you may not have placed the wires in the correct places. The e-unit actualy performs the task of re-wiring the motor so did you reverse the direction with the e-unit or switch some wireing yourself? The e-unit actualy reverses the current flow thru the armature but not the feild winding.
Lastly did the engine run in both directions before it fell off the track?
I will try to send you a diagram of the e-unit but not sure it will be succesful.