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(Sorry if this posts multiple times, but I've tried this twice and am not seeing it show up in the forum. Please delete if I did something wrong unintentionally).

Hi, first time poster here but I've been reviewing the threads for over a week now. What an amazing resource! I have a post war set gifted to me by my Father in Law who's had this set since he was a boy. I am determined to get it all running and keep it running for my grandkids someday. And I've accomplished so much over the past week from learning here on the forum. But I'm stuck and need some help.

First and most important is the Prarie 224 engine.



As you can see :) I've opened it up, learned so much, and did alot of cleaning. Now that its clean (I think) im having trouble getting it to run. Sometimes the motor runs, sometimes it doesnt. Either I've broken something while cleaning, touched something I shouldn't, or something has just gone.

Some details first:
  • I've cleaned the armiture face and grooves. Used 50% isopropyl alcohol - maybe a no-no? Didnt use an erasure or any type of sandpaper.
  • I cleaned the brushes, wells, and springs using the isopropyl.
  • Lubriacted and oiled per the user manual (and greenberg book which is great)
  • I broke one soldered connection (to the e-unit) and re-soldered it
  • Again, the motor runs but then when i stop it, and try again, it doesnt always run.
  • to test it i've been putting one wire from the transformer on my bench to the roller plate, and another to the metal frame
  • also have put one wire onto the metal pin going to the brushes and one on the frame.
  • once or twice, i put both wires to both metal pins going to the brushes. didnt seem like it liked that :(

So either i ruined the armiture face by using the alcohol?
Or ruined the motor by connecting live wires to both brush pins?

I'm thinking maybe there's a short?

Finally, i just found something on another thread here. The e-unit doesnt seem to be working at all. when the engine does run i dont see the drum spinning or anything. I didnt clean it but i did re-solder a wire to it (will point out below). I read that a broken e-unit can cause shorts and eventually burn out the motor?

Ok, now for some pics



Ok, the solder point on the left is the one i repaired. When this broke, nothing worked. when i resoldered, things started working more consistently. I have the wiring diagram on my bench but not with me while writing this.





The wiring, as you can see, is very old. But I'm hesitant to replace unless i know its bad.



Here's the pins to brushes I'm talking about (again, manual is on the bench so forget what these are called)



Here's how it all looks after I cleaned - I think its pretty good?





Only other thing I can think of is the brushes are not making good contact to the armiture?



Sorry for the long post but I figured the best way to get help is to give as much info as possible!

Thanks in advance!
 

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Railroad Tycoon
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24,480 Posts
The IPA won't hurt it.
50%? What was the other 50%?:confused:
99% is better.

I agree with T the wires look terrible. One could be causing a short?

Do you notice the wheels are bad?
Though it still should run.
Are the springs sitting right on the brushes?

Did it run before you cleaned it?

Edit,

Did you run it after you cleaned it with the shell on?
Try it with the shell off.
 

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Discussion Starter · #4 ·
Thanks for getting this posted.

T-Man - LOL, I laughed out loud "your wires look terrible". enough said. so guess that could be the problem. I learned about the e-unit only right before the last time i was able to get the motor to run. From what I could tell, it didnt respond at all - no turning, clicking, anything.

big_ed - yea, it only says IPA 50% as the only active ingredient. maybe the other 50% is water.
Anyway, I did notice the one wheel has broken off but, youre right, it didnt impact anything from what i could tell when it was running last year.
The springs appear to be on the brushes properly, at least from what i can tell (one end of the brush is narrower).
So it did run but before i cleaned it but it was making a loud, squeaking kind of noise. that was what prompted me to open it up. when i got it back assembled, it ran before the shell was on. by the time i had all the parts back together and put it on the track, it didnt run. so then i took the shell off, and it would run. then not. then fooling some more i mustve broken the one solder point. once soldered back on its been intermittent - sometimes works sometimes doesnt.

I read that a faulty e-unit can cause shorts and ruin the motor?

Whats the best way to test the motor itself, aside from all the wiring? Touch one live wire to one of the brush pins and another to ground? when i do that it doesnt run.

Help! (my father in law will be over in two days and i hope to not have his 1946 engine still spread out on the operating table.
 

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Discussion Starter · #6 ·
Thank you T-Man. I've learned so much already from all of the valuable posts you have here on the forum. So I read the bench test thread there but i dont have any jumpers. Also not sure about where they go exactly. On my workbench i have a small transformer that I've been using for my testing. Is there a way to just connect with that? Or should I get some jumpers?

Also, would you recommend I change out all the wiring?
 

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Yard Master & Research
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The two power lines touch one brush and the frame. You need the coil wire on the frame (yours is long) and connect it to the other brush.

Yes on the wiring every bit. All the way inside to the center rail contact, and the coil on the frame conection can be tricky. This wire is thin and be careful when ripping out the old wire.


Rewire thread
 

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Discussion Starter · #8 ·
ok, so i need to get some wire jumpers to do this right.

sorry for so many questions. where is the "coil wire on the frame" youre referencing?
 

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Yard Master & Research
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10,864 Posts
The wire between your fingers.




The wire from the bottom shoe is the center rail contact roller.

In case you missed this in the above post.

Rewire thread
In fact the same engine.

YOU DID TAKE GREAT PICTURES!
 

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Yard Master & Research
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The banana clips are convenient. For 5 bucks you get a package at Radio Shack. If you have the wire, the clips are sold in a bag at a craft store like Michaels in the jewelry section. Those little clips are used more without wires than with (by me). 22 gage wire is ok 20 may be a little stiff. Strand wire is better than solid. Again Radio Shack has small rolls.

Since you are in a crunch you can cheat and leave some leads to make it easier. On the coil and the center roller. The eunit should be taken apart to rewire. ANother problem. Later you can go back to finish.

To really cheat, and if you have a lot of wire, pull the insulation off and use it on the old stuff by disconnecting on side and feed it on.

Then I have an e unit repair link

Also the schematic for the motor.

A repeat but the same thoughts

Just some thoughts. The eunit does pry apart don't bend the sides. and getting it back can test your patience.
All you can do is take your time to do it right.

Aside from the wheel it looks in realy good shape.
Good Luck.
 

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Railroad Tycoon
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Thanks for getting this posted.

T-Man - LOL, I laughed out loud "your wires look terrible". enough said. so guess that could be the problem. I learned about the e-unit only right before the last time i was able to get the motor to run. From what I could tell, it didnt respond at all - no turning, clicking, anything.

big_ed - yea, it only says IPA 50% as the only active ingredient. maybe the other 50% is water.
Anyway, I did notice the one wheel has broken off but, youre right, it didnt impact anything from what i could tell when it was running last year.
The springs appear to be on the brushes properly, at least from what i can tell (one end of the brush is narrower).
So it did run but before i cleaned it but it was making a loud, squeaking kind of noise. that was what prompted me to open it up. when i got it back assembled, it ran before the shell was on. by the time i had all the parts back together and put it on the track, it didnt run. so then i took the shell off, and it would run. then not. then fooling some more i mustve broken the one solder point. once soldered back on its been intermittent - sometimes works sometimes doesnt.

50% hmmm, I don't go shopping for my IPA as I haul it I just bring home sample bottles. Must be water for the other 50% that someone blends after they get 99%.
I have seen 71%, but that has a denaturing in it most of the time ethyl acetate.

I think it is in your wires, some looked spiced together and the one is taped.
If I see it right, the one that goes down to the power pickup point doesn't even have tape on it.

Brushes too tight? A easy quick way to check is to back off the brush plate screws just a hair and see if it runs.

It could be the e unit too, but I would replace the wires anyway as they need it.



Edit,
Squealing might be dry gears, try 5/20 motor oil. On all some of us here don't use the lube anymore just a few drops of motor oil. The Axle bearings need a little lube too, don't forget them.
 

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Discussion Starter · #13 ·
Ok I'm back. Been spending the last few weeks trying to prove my motor and eunit are working....and they are. Took me awhile to get it right but ran a successful bench test and proved both the motor and unit are working (see this link for details http://www.modeltrainforum.com/showthread.php?p=110145#post110145a ).

So like stated above looks like I just have some bad wiring, old wiring, etc. as I started to put the entire engine back together it responded less and less, presumably from the tucking and folding of wires. So contemplating retiring the whole thing. Also using some links above maybe also servicing the eunit while I'm at it. Figure if the motor is still good I should give this thing an entire overhaul.

Will post progreso and pictures as I go.

Tanks again all!
 

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those pre and post war prairies are sweat little engines. I grew up with a 225E. I have it now. collected a few more over the years. You are on the right track! pun intended!

rewire like you are- E-Unit-watch those fingers. like they said, getting this right will try your patience.

the gears look worn to me from the pics. does everything roll back and forth smoothly?
On mine, the axle bushings were warn so badly, the gear train on wheels were barely meshing. I replaced the bushings and left the pointed gears alone for now. she runs like new and smooth as silk.

once your done with it, your grandson's grandson should be able to enjoying it!
 

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Discussion Starter · #15 ·
thanks plandis. still reviewing as much documentation and threads here on the forum before i try this. i really need to brush up on my soldering skills to. tman has supplied some good links.

as far as the gears, i didnt notice them looking worn. will have to go back and check that. everything does roll smoothly, IMO.

Yep, very excited to try to restore this unit (and the entire collection) for my kids, etc. I love how well these are built and the promise of reliability for years and years to come!
 
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