# Lionel 1688 Motor



## Ohio027 (Dec 29, 2012)

So, I bought a box of prewar Lionel at an estate sale. It had two 1688 and one 6010 loco, so I figured I did well. Until I got home and only one 1688 runs, and only backwards and only for a short while. I cleaned it up, checked the e-unit fingers, oiled it up, and--same thing. The motor is good 'cause it goes like heck when it does run. The e-unit will click once or twice when I try running it, then nothing.

To try and salvage something out of this box o'junk, I want to dump the e-unit and just have the loco run forwards. My question is, how do I go about that? 

Any help is appreciated--and if anyone wants a 1600 shell and and a 6010 shell, let me know.


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## gunrunnerjohn (Nov 10, 2010)

You can rebuild the E-unit, there are a number of thread on the topic here.

To run it in a single direction, wire the track pickup to one brush, wire the other brush to the field connection, the other side of the field is frame ground already. If it runs backwards, swap the brush connections.


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## teledoc (Oct 22, 2014)

Which version of motor and version of 1688 are you having a problem with. If you go into the "Tinplate" section, there is a thread all about the 1688/1688E and the other two torpedo locomotives. I have analyzed every version of the 'Torpedo' locos for the 027 scale. As Gunrunnerjohn stated, just rebuild the E unit, with a new drum and new finger contacts. If not, I can walk you through wiring it in forward only, but I need to know which motor you are working with. Contrary to what most think, the 1688/1688E locos use three distinct motors during the 1936 issue up until the last version. Read my thread so you understand what I am talking about.


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## Big Ed (Jun 16, 2009)

Ohio027 said:


> only one 1688 runs, and only backwards and only for a short while. I cleaned it up, checked the e-unit fingers, oiled it up, and--same thing. The motor is good 'cause it goes like heck when it does run. The e-unit will click once or twice when I try running it, then nothing.



When you say "oiled it up" you didn't oil up the e unit did you? The plunger might stick if you do.
Sometimes the plunger sticks anyway, did you spray a little contact cleaner up the plunger?

Are you running the motor out of the shell when you are testing? Sometimes you can see something wrong.
Maybe a bad solder job on one of the wires?


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## teledoc (Oct 22, 2014)

*Type I 1688E motor wiring for forward only*

I am going to presume that you are dealing with what I refer to as the type I motor that came in the first issues and mounts to the body with two short screws through the running boards. The type II is not very common, so I won't mention it. The last type III is exacly like the Postwar 1654 motor that mounts with two screws that pass through the body horizontally.

Here are two photos of a Type I motor, without the E unit, and how to wire it for forward running only. The Type III should be the same. One wire is connected to one solder connection on the Field coil, and goes to the brush holder tab. The other Field Coil wire is connected to the pick up assembly.


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## Ohio027 (Dec 29, 2012)

Thanks for the help, everyone. 

For the record, I did read Teledoc's 1688 thread and it was helpful. Looks like I have the Type III motor per that thread--it mounts on the two screws through the body. 

I thought about tackling the e-unit rebuild, but decided that reverse isn't that important with this engine. I don't use it often with my other locos anyhow. A rewire, some new paint and a new front truck and we'll be good to go!

And no, I didn't oil the e-unit, just used a ton of contact cleaner. Oil was for the gears and axles, just like y'all taught me...


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## teledoc (Oct 22, 2014)

Ohio027, The same set up is for the type III motor. The one brush is the ground return path, which should be the right one looking at the brush plate. Make sure the right hand screw is contacting the washer when it is screwed in, otherwise you lose the ground return path. The pick up collector wire will attach to the ungrounded side of the field coil solder joint. These motors are easy to test and get running, especially if you want to eliminate the E unit, like you want to.

I have all versions of the 1688/1688E and the motors, in various states of rebuilds. The motors on Lionel 258's, & the 1681's are pretty much the same as far as testing and wiring. They are basically very simple to work on. The worst case scenario is a defective armature, and then E unit problems.


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