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I have a couple of centercabs (including my new 628) with bad E-units.  I'm not inclined to rebuild them at the moment, so: 

Rather than shell out $40 for new ones or $20-35 for a Lionel disc switch, is there a way to use a $3 toggle switch from Radio Shack as a reverse switch?  If so, how?



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On a Lionel post war motor, the power goes through the armature coils and then through the field coils.  They are in series.  To reverse the motors direction, reverse the wires to the brushes, without reversing the power to the field.  In most postwar motors, one field wire is grounded to the motor frame, so reversing the brushes or the way to go.  There are a few post war motors with double wound fields.  They will not have three position e units and would be connected differently to reverse them.  In Rob's drawing, the red wire would be coming from the current collector (center rail) and the black wire would go off to the field connection. I do not specifically recall the 628, bur frequently Lionel put a third lug on the brush plate for the field lead to connect to.  

Shades of the 30's.  Before the e-unit came out around 1940+/-, Lionel locos had a manual switch for reversing.  When the e-unit first came out, Lionel added an E suffix to loco numbers to indicate its presence.

QSI used to make an device called an ACRU, silent electronic reverse unit that always started in neutral-before-foward on powerup.  Excellent device.

Okay, I think I have this sussed: 

Reverse Switch

Using Lionel's color schema, here's how I think things should be wired.  The black wire from the pickup goes to one center contact of the DPDT switch, the yellow wire from the coil goes to the other, and the blue and green wires go to outside contacts with a crossover.   Thus, when the blue wire is energized, the green brush energizes the coil, and vice versa.

Have I got it?   



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  • Reverse Switch

I favor manual reversing switches to replace troublesome e-units. If you use a center-off switch, the off position allows you to park a loco anywhere on your layout. Manual reversing switches are also handier for MU'ing locomotives. I position the switch handles to stick out the existing slot for the e-unit lever.


For 2-position e-units used with Lionel double-wound fields, a SPDT switch does the job. One field winding is used for forward, the other for reverse.


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  • 100_4143
Last edited by Ace

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