# Bench Test



## T-Man (May 16, 2008)

This is for AC motors mostly Postwar Lionel. You need three jumper wires. The first goes to the center rail and to a brush holder. The second goes from the other brush holder to the positive side of the coil behind the eunit. As seen in the picture. On top of the motor is a small metal plate that is the ground for the coil to the frame. This is where the last wire goes to the outside rail. Then you turn on the juice. Both engines work after a cleaning. They are the recently acquired 1666 and the 224. The wires are old so they need to be changed out. The engines in this box lot are in very good codition. all you have to do is see through the dirt. The shells have no broken pieces. The 675/2025 was the only one with breakage. The motors show signs of wear but nothing excessive. The wheel bushings are in good shape with very little play.


----------



## bryher (Dec 17, 2011)

Tman, I've read this thread over and over but still a little stuck. Can't understand where all three connections go? Is it

1-from center rail to one brush holder
2- other brush holder to? The metal plate above the motor coil? Or somewhere on the eunit?
3- the same metal plate to the outside rail?

Sorry. I'm so close to getting the connections right.

Thanks!


----------



## tjcruiser (Jan 10, 2010)

Bry,

I'll chime in here, if I may.

First, it's important to note that the e-unit has been electically removed from operation here (temporarily).

Second, Lionel wired there motors (depending upon the specific loco) in either one of two ways:

1. (What you see here.) "Hot" power goes from a center-rail pickup into one of the brushes (via the brush can). From there, power runs through the spinning armature, then back out through the other brush / brush can. From there, it goes next (via a wire) into the electromagnet "field winding" (or "field coil) that is mounted in the frame. After flowing through the field coil windings, power exits via a ground to the frame itself, and from there, back out to the track through the outer wheels. So, in the "banana clip" jump, above, one lead brings power to a brush can; another lead brings power from the other can over to the un-grounded field coil windings end; and a 3rd lead brings power from the grounded field coil winding end back out to your transformer's ground (or outer rail, etc.).

2. Some Lionel locos flip-flop the electrical schematic ... Power goes into and then out of a field coil winding. From there, it flows into one (ungrounded) brush can, through the spinning aramature, and then out through the other (grounded) brush can, into the motor frame, and out to the track via the outer wheels.

I should note that one the e-unit is introduced, a change in loco direction is accomplished by flip-flopping the path of current through one of the components above. In wiring option #1, the e-unit flips wiring to the two brush cans. The path of power throught he field coil stays the same. In wiring option #2, the e-unit flips wiring to the in/out tails of the field coil. The path of power through the brush cans (and armature) stays the same.

Hope that helps,

TJ


----------



## bryher (Dec 17, 2011)

Hi TJ, that helps alot. Ok great. I have a picture below of my engine. I thikn the the power goes from the center rail (through the contact roller right?) and right into the e-unit itself - i think this is the wire to the far right.










Does that sound right? 

PS - I know, my wiring is really bad  If I can prove the motor is still good, I may attempt to rewire the whole thing.

PPS - this is my main thread on this engine
http://www.modeltrainforum.com/showthread.php?t=9811


----------



## tjcruiser (Jan 10, 2010)

Your e-unit is pulled away from the motor, but it's not isolated electrically. It's still wired to the brush cans and the field coil input. However, for an e-unit to work properly (specifically, for the solenoid to operate), the metal casing of the e-unit must be touching/grounded to the motor frame.

If you want to test the motor with the e-unit, you need to run a ground lead (banana wire) from the e-unit metal frame to the motor frame. Run a "hot" power lead from your transformer directly to where the black wire from the middle of the loco attaches to the fiber plate sticking out the side of the e-unit. Put your banana clip right on that solder joint. Run a ground from the e-unit metal side to the motor frame (as mentioned above), and then another ground wire from the loco motor frame back to your transformer (or outer rail, etc.).

Your e-unit lever is currently (via the photo) set to engage the e-unit. If you move the lever to the left, it will disengage the e-unit, leving the e-unit internal drum/finger switch in whatever direction/position it was last set: fwd, neutral, reverse, neutral. Note _neutral_ is a possiblity, in which case you'd see no action with the motor.

Try that first, and see if you see any signs of life.

Depending upon results, it may be that you want to unwire the e-unit from the motor (sever the 2 yellow and 1 black wires), and resort to the "no e-unit jumper test" per the prior posts. I wouldn't go that route, just yet, though. Follow the sequence in my paragraphs directly above.

TJ


----------



## bryher (Dec 17, 2011)

TJ, it worked! Took me a few tries to figure it out but I was able to prove the engine works by itself with the eunit. I'm so glad you helped me figure this out and my motor is still good. Also thought the eunit was bad but turns out that works too! I successfully tested the motor, the functionality of the eunit several times. Ten just to see where the problem might be I slowly started to reassemble the while thing. Heres what I did...

1) with the eunit connected to the wires but connected not the motor frame (as in my picture above). SUCCES.

2) then I connected/mounted the eunit to the frame with the single screw. Using the same connections. SUCCESS.

3) then I connected the entire motor and chassis to the frame of the prarie 224 engine by means of the single screw that comes down from the top of the frame into the motor, SUCCESS.

4) then connected the front wheels -this is where the wires had to be squeezed a bit so expecting problems. SUCCESS

5) then. Connected the back wheels. SUCCESS

6) then I reassembled the pistons and arms to the wheels and did one final test. FAIL

So I knew at this point is where I have problems. So I jiggled the eunit switch sticking out of the top of the engine frame now.....and it worked! I put the entire engine back on my display track and it started but not great. 

So, I'm thinking it's just the poor wiring I have on there now? Probably causing some sort of short maybe? I wanted to eventually think about rewiring but first prove the motor still worked. Mission accomplished! I already have reviewed a couple of threads on retiring from Tamar and just need to brush up a bit, including my soldering skills which a really novice. Is it worth trying to require the entire engine myself or too risky? Ill go back to my original thread in my engine and continue the progress there.

For the record, here's how I wired for the bench test following Tmac and TJs guidance...

1) connected one jumper wire from a terminal on my transformer to the eunit. Specifically to the solder point on the fiber piece indicated by my thumb in the above picture.

2) connected another jumper wire to the metal frame of the eunit itself. The end of the jumper wire went to the metal frame of the motor housing.

3) finally e last jumper from the same motor housing frame to the other pin on my transformer.

I didn't use any tracks and just held the motor myself. It worked!

Again, thanks for your guidance and patience here. I will continue to document my progress for others as I go.


----------



## servoguy (Jul 10, 2010)

Don't forget the E unit has to be vertical to work. It will not work if the loco is lying on its side.

If you had trouble when you reinstalled the side rods and valve gear, you may have the valve gear installed wrong which will bind up. Make sure the wheels rotate freely after you reassemble everything.


----------



## tjcruiser (Jan 10, 2010)

Bry,

I'm thrilled to hear your good news. Patience paid off!

Bruce (Servoguy) has a good point about the drive rod linkages. Make sure that everthing is free-rotating, without any misplaced/binding components.

Drop us some pics of the recovering patient!

TJ


----------



## Konga Man (Dec 12, 2010)

servoguy said:


> Don't forget the E unit has to be vertical to work. It will not work if the loco is lying on its side.
> 
> If you had trouble when you reinstalled the side rods and valve gear, you may have the valve gear installed wrong which will bind up. Make sure the wheels rotate freely after you reassemble everything.


If your wheels are warped, that can also cause the rods to bind. After you get the linkage back together, make sure that the rods will clear the wheel rims.


----------



## bryher (Dec 17, 2011)

Thanks all.



servoguy said:


> Don't forget the E unit has to be vertical to work. It will not work if the loco is lying on its side.
> 
> If you had trouble when you reinstalled the side rods and valve gear, you may have the valve gear installed wrong which will bind up. Make sure the wheels rotate freely after you reassemble everything.


-ok will keep that in mind. I've had this thing apart so many times I'm starting to figure out all the gears and such. 





tjcruiser said:


> Bry,
> 
> I'm thrilled to hear your good news. Patience paid off!
> 
> ...


- thanks TJ. Ok will take some pics as I go (maybe also a video....see below  )






Konga Man said:


> If your wheels are warped, that can also cause the rods to bind. After you get the linkage back together, make sure that the rods will clear the wheel rims.



Got it. I think I've reassembled everything correctly b/c the wheels seem to move freely. However I still hear a little of the same grinding noise that originally caused me to open this up in the first place. If I'm able to post links to videos here, I'll try to take a quick video and link it all in my original thread so as to not hijack this threads off topic. Here's my thread

http://www.modeltrainforum.com/showthread.php?t=9811&page=2


----------



## gunrunnerjohn (Nov 10, 2010)

Note that the AC motors do tend to growl a bit. The vertical ones are worse, like the #41 Army switcher or the #50 gang car, but all of them are on the noisy side.


----------



## bryher (Dec 17, 2011)

hmmm, ok maybe thats it. im gonna try to take a short video of it to try to capture the sound.


----------

