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Discussion Starter #1
1. The first old guy runs great and as I was browsing the net I noticed a couple of sites loosely referred to it as prewar due to the 2 piece pickups as opposed the postwar 1 piece. The sites I visited were not very clear on this, thus my question 1, really prewar?

2. Everyone tells me that Marx locos are virtually bullet proof, yet this 666 is the third loco (not all 666) in the past 2 years I got that is dead. No light, no sound, no movement, nothing. Took out the brushes and cleaned holders, armature, etc.

Can brushes go bad? These were not dirty or oily, however I did notice one that one was a bit loose in the holder but didn’t move once I re installed the spring to its proper location. What to do????

Thanks for any comments.

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bottom postwar.jpg
 

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Does all the wiring look intact? Does it have an E-unit? Have you tried a direct connection from the transformer to the motor?
 

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Does all the wiring look intact? Does it have an E-unit? Have you tried a direct connection from the transformer to the motor?
Everything looks clean and connected properly...no loose wires or mickey mouse solder joints. It must have the marx version of an e unit cause its supposed to go in reverse. Haven't tried direct connection....was afraid I wouldn't do it right and short something out.
 

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If you have a DVM, measure the impedance between each adjacent winding on the armature face. IIRC, they should read < 10+ ohms. If any measure open or 30+ ohms, your armature is bad. That's not likely but it did happen on one of my Marx loco.'s (my fault).

You won't do any damage by trying a direct connection with a transformer for several seconds at a time. If there's a short or the motor is "frozen" the transformer's circuit breaker will kick in. One wire to ground (motor casing) and the other to the brush that has an attached wire. Is there any response to a direct connection - buzzing, vibration? Does the motor spin freely turning the wheels by hand?
 

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Discussion Starter #6
Did it work before you replaced the slide shoe?
If the slide shoe is the copper part on the bottom, no, I did not replace it...it (The 666) was dead from the moment I got it home.
 

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Do the wheels turn freely as stated? Yes the brushes can go bad, in that they ware down and dont make contact. Thats rare though it happens. E bay used to have a pretty good marx train guide on ther site.
 

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Most likely the E unit is not working properly. These E units are simple in operational theory but they do like to stick if not used frequently. The link shown below will take you to a fella on YouTube that is a Marx Train guru of sorts. The link will take you to his list of videos that contain comments concerning Marx E units.

 

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Most likely the E unit is not working properly. These E units are simple in operational theory but they do like to stick if not used frequently. The link shown below will take you to a fella on YouTube that is a Marx Train guru of sorts. The link will take you to his list of videos that contain comments concerning Marx E units.

Except Benz Trains mostly bypassed E-units or replaced them with manual switches instead of fixing them. Only once did he recommend WD-40 after MTF member Panther recommended it.

If you remove the motor, you'll see it's there's not a obvious opening in the Marx E-unit. But if you turn the motor over there is a bit of an opening. With the red "straw" try squirting some WD-40 or CRC contact cleaner (preferred) into the E-unit slot. Then use a transformer wired to the motor to repeatedly cycle it. The E-unit will only cycle in the upright position so you will turn the motor over, squirt, and turn it back upright and cycle. It may take repeated attempts but this has worked in the past. You should be able to here the E-unit "click" on each power up cycle.

The fact that you get no action on powering the motor implies that you either have a wiring problem or the E-unit has a bad internal contact (Marx E-units do not have a neutral stage, only forward and reverse).
 

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Out of curiosity in your last marx picture on left wheel, does that gear mesh with the teeth on wheel it appears the gear is resting on top unlike wheel to the right ,but pictures can be deceiving.
Either way as you say wires and solder joints look fine then its your e-unit or armature.
 

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Contact cleaner. I wouldn't use wd 40. First see if the wheels turn freely. If they dont then no need going to step 2:)
 

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Out of curiosity in your last marx picture on left wheel, does that gear mesh with the teeth on wheel it appears the gear is resting on top unlike wheel to the right ,but pictures can be deceiving.
Either way as you say wires and solder joints look fine then its your e-unit or armature.
It appears to be a double reduction motor in that last pic of the second loco. The prominent gears don't mesh with the wheel gears. Rather, their associated gears mesh with the wheel gears, hence the reduction.

549625
 

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... just looked at our 666 same as above pic.
I knew because I have a 1666 with the basic motor assembly; same gearing. Hate the traction tire. With only one drive wheel on that side it doesn't reliably throw my self-tending switches at higher speeds. And that wheel is smaller with a significant groove for the tire. You can't just remove it. The loco wobbles on the smaller wheel. I tried :(
 

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The link shown below will take you to a fella on YouTube that is a Marx Train guru of sorts. The link will take you to his list of videos that contain comments concerning Marx E units.
I offered, to johnboy, the link to Benz Trainz YouTube just so he would have some visuals to look at concerning the Marx E Unit. There are a plethora of short YT's from Ben to choose from. Ben usually does bypass the non working E Unit but he has some videos showing how the E Unit is suppose work. Ben's videos do get to the point rather quickly and generally presented in a professionally manner. Lots of good info concerning Marx Trains but one may have to dig a little thru his multitude of videos to find what you are looking for but it is worth the effort.
 

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Discussion Starter #16
Thanks to everyoneall for the discussions, comments, link, and info. I'll get started on it again next week. Parkinsons very bad last day or two and it's hard to work on project (and also type!).
 
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