ByPassing the E-Unit

If you suspect the E-Unit on a postwar Lionel engine is acting up, and you want to test the motor directly on your workbench by by-passing the E-Unit, how do you connect the transformer leads? I assume one lead goes to ground, and the other needs to connect to both one of the brushes (depending on which direction you want to test the motor in) and simultaneously to the non-ground lead on the stationary coil. Is that correct?

John Gottcent

Hello John,

I do not know what acting up means exactly, but probably that it remains humming or doesnot alternate the directions. Can’t you simply put the E-unit in the fixed direction, or am I stupid now? Bypassing the way you describe (ground on the body and power on one of the brushes), doesnot work though. I tried that on my prewar engines and that never worked with me. But I am sure there are folks here that know much more about the intricate E-unit.

Good weekend,

Egbert

Sounds good to me! Here’s a schematic: http://pictures.olsenstoy.com/cd/locoinfo/loc-e-p1.pdf

No. The way you describe would put the armature and field coil in parallel. They should be in series. Wire it this way: center rail to one brush, other brush to ungrounded field terminal, leave the other field terminal connected to ground (the frame of the vehicle). If you can be sure that the e-unit is in its neutral position, you can do this wiring without disconnecting the e-unit. Otherwise, you will have to disconnect at least the two wires between the e-unit and the brushes.