# Marx help needed, Only buzzes



## tkruger (Jan 18, 2009)

I have been running HO for years. O is brand new to me. Today I received a Marx 400 train set with a 25w transformer. Cleaned the track up and connected the transformer to the track. When attempting to run the train the Light lit and the train buzzed. It looked as if it jerked slightly forward and then stopped. Turning it off and on quickly made to loco act as if it wanted to go in reverse but could not. The wheels on the locomotive move freely when off the track. When power is applied they are locked up.

I want to use this to start a second layout. Other than the tender needing replacement the set is in great shape cosmetically. Spent $15 for it and I am hopping to get it working.


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## Big Ed (Jun 16, 2009)

Have you tried taking the shell off and cleaning it?
Might just need a good cleaning.


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## tkruger (Jan 18, 2009)

big ed said:


> Have you tried taking the shell off and cleaning it?
> Might just need a good cleaning.


From what I can tell it looks well lubed and clean. The wheels are very smooth when hand turned. 

Is there a way to make these go in forward and reverse? If so how is that done? I have heard that some O27 locos have E units but I do not know what that is. I have been an HO guy and understand DC locos but AC is new to me.


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## Big Ed (Jun 16, 2009)

tkruger said:


> From what I can tell it looks well lubed and clean. The wheels are very smooth when hand turned.
> 
> Is there a way to make these go in forward and reverse? If so how is that done? I have heard that some O27 locos have E units but I do not know what that is. I have been an HO guy and understand DC locos but AC is new to me.



I don't know much about Marx. Is there a lever anywhere sticking out of the loco?

An e unit has a lever and you can switch directions.
Search e units here there has been plenty posted about them.

I don't know if a Marx has them.


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## Big Ed (Jun 16, 2009)

At least some have them.

See if this link is of any help.

http://www.thortrains.net/marstart.html


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## tjcruiser (Jan 10, 2010)

TK,

The fact that it made a lurch to try to move is a good sign. Tells me that the field and armature windings are likely OK.

Can you remove the loco shell and posts some pics of the motor?

It's likely that the motor has an auto-reverse e-unit. Basically, it's a little electromagnet solenoid plunger device. As power is applied, the an electromagnet field sucks the plunger up. With each power throttle-down, the plunger drops back, and moves a little switch toggle in the process. It's that switch toggle that redirects the path of wiring in the motor to dictate forward or reverse. (Or, in the case of some locos, a neutral position, too.)

It may be (???) that your e-unit is simply stuck in neutral. But then again, it may be that Marx doesn't have a neutral position in its e-unit.

T-Man's thread here shows a Marx loco and a Marx e-unit. I'm not sure if this is the same as your, but have a look:

http://www.modeltrainforum.com/showthread.php?t=3108

A thorough cleaning of all parts of the motor and e-unit will help. Use GooGone with q-tips, pipe cleaners, etc. Remove the contact brushes and clean those and the armature's commutator face, too.

Post pics ... we'll try to help.

TJ


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## Big Ed (Jun 16, 2009)

Scroll down in the link I posted.

They have e units.

Marx Motor


















The e unit is all that copper you see. I think, I never worked on a Marx.

If you have a lever put it on the track apply power and work the lever back and forth. sometimes the lever is not making contact with the contact points.


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## gunrunnerjohn (Nov 10, 2010)

I'd start by checking the brushes and cleaning the commutator, that's what the symptoms suggest.


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## tkruger (Jan 18, 2009)

There is no lever on this one. The little reading I have done states that this does not have a neutral position put does have forward and reverse. Below are some pictures.


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## gunrunnerjohn (Nov 10, 2010)

Better focus would be a big help. Looks like the brushes are in the last shot, but I can't be sure of how they come out. Is there a little spring right across the top of those brush holders? I should probably dig out an old Marx motor and see what they look like...


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## tkruger (Jan 18, 2009)

I have the brushes currently out and am cleaning the comm. Will let you all know what happens.


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## gunrunnerjohn (Nov 10, 2010)

Seems like the top suspect, followed closely by the contacts on the E-Unit. FWIW, a lot of the Marx stuff I've seen has the two speed E-unit, no neutral.


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## tkruger (Jan 18, 2009)

Just cleaned the comm. Will re assemble and test.


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## Big Ed (Jun 16, 2009)

Much better picture.:thumbsup:

It looks like a clean engine.


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## tkruger (Jan 18, 2009)

Its Alive!! 

That last picture was after cleaning the comm. Prior to that it was showing signs of needing that. Now I just need to get the track cleaned properly. It runs but not as well as I want it to, track sparks hear and there.


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## Big Ed (Jun 16, 2009)

90 percent of the time it just needs cleaning.

Try adjusting the spring pressure on the brushes a little.
Sometimes there is too much or not enough.
Leave the shell off and experiment, it should run without the shell.

Sometimes backing off of the brush plate JUST A HAIR will make a difference, if it runs better the spring tension needs adjusting.

Clean the rail contact and wheels too.

I must add I never worked on Marx, I'm talking Lionel tips I picked up here and there.

Whats holds the brush plate on 1 screw? 2?


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## gunrunnerjohn (Nov 10, 2010)

Sounds like you're on the road to happiness.  One thing for sure to do is lightly oil both ends of the armature, and also lube the gears.

Track sparks indicate you need to clean the wheels, pickups, and the track.


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## tkruger (Jan 18, 2009)

One screw and two post hold the brush plate on. There is no built in way of adjusting the brushes that I can find. The screw that holds the plate on also holds the bearing that hold the armature in place. If I shim it the armature will wobble. The wheels have been cleaned and the loco lubed. The track was cleaned just enough to get it going and test it. I am undecided between cleaning this and replacing with new when I build the layout. The pins are loose and it needs work. Three of the curves almost stop the loco.

As for lubeing the gears I am for the first ing with a loco hesitant to do that. On this Marx loco the drive gears are the inner rim of the wheel. There is no space between the botom of the rim an the gear. I am afraid that with this design any grease will pick up all the dirt in the track bed.

For an old loco it is currently running well.


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## tjcruiser (Jan 10, 2010)

Per Bruce (Servoguy), I've been a convert to 5W-20 or 5W-30 motor oil for use on my locos ... all moving joints, and even a tiny drop on the commutator face, too.

Glad to see it was a simple clean that got you back up and running!

TJ


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## Big Ed (Jun 16, 2009)

tjcruiser said:


> Per Bruce (Servoguy), I've been a convert to 5W-20 or 5W-30 motor oil for use on my locos ... all moving joints, and even a tiny drop on the commutator face, too.
> 
> Glad to see it was a simple clean that got you back up and running!
> 
> TJ


I am going that route too,all except a drop on the commutator face.

I can't seem to do that.

What keeps the tension on the brushes on a Marx engine then?
The piece that holds them? Why is that piece slotted then. If there is nothing holding them wouldn't they jump around in their holders, the piece with the slot.


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## gunrunnerjohn (Nov 10, 2010)

As far as the track, no reason you can't clean up what you have. I have track pliers to crimp the ends for a nice tight fit of the pins. I take any pins that have any discoloration on them and buff them with my Dremel with a Scotchbrite wheel before using them again.


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## tkruger (Jan 18, 2009)

big ed said:


> I am going that route too,all except a drop on the commutator face.
> 
> I can't seem to do that.
> 
> ...


The tension is held by a spring. The spring is wrapped around a bar on the plate.


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## Big Ed (Jun 16, 2009)

tkruger said:


> The tension is held by a spring. The spring is wrapped around a bar on the plate.



Is it running better (faster) now?
Sometimes it needs to be run again for a while to come "alive".
But you can't run it around huh?hwell:

Clean up some track and make sure the pins are tight and give it some run time. A small oval will do it.

Try flipping the brushes.
Maybe you need new brushes?


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## gunrunnerjohn (Nov 10, 2010)

I have a small oval in the back of my workshop just for testing trains.


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## tjcruiser (Jan 10, 2010)

I like the light mounted directly to the e-unit. I've never seen a motor like that before. Dual function / multi-purposed / multitasking. Pretty high tech (for a Marx train, and all!) :thumbsup:

TJ


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## gunrunnerjohn (Nov 10, 2010)

I think I have a Marx E-Unit in my junkbox with the light socket on it, I found it interesting, since I never saw a Lionel unit like that.


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## tkruger (Jan 18, 2009)

It is running better after a little run time. I have but it away for the time being. Spent time building a 4x3 table for it. Will have shelves underneath for storage. Sitting next to the bigger HO layout.


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## Big Ed (Jun 16, 2009)

Nice bridge.:thumbsup:


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