# Engine hums but won't run



## Suamico Pete

Greetings- my first time on this forum - also new to MTF. I'm just getting into model RRing - not sure how far I will take it. I have a couple of old trains to start with. I have a Lionel 1130 starter steam engine, circa 1953-54 - got it when I was 6. I haven't run it in 20 years or so. Cleaned it up an lubed it. Ran great for a few days that just quit. I have torn it down, cleaned the brushes and armature face. Engine E-Unit coil hums loudly - will activate rotation of E-unit drum - but appears to be stuck when current is applied. Have taken the motor apart as far as I can without cutting wires. Don't see any broken wires or pieces of dirt inside motor. Cleaned E-unit drum. Bench-tested with no results. Wheels and gears are all free so no mechanical linkage issues. I ran it for a short time (1 hour max) with a 40 watt Marx transformer. This engine is supposed to draw up to 35 watts.
Questions:
Can E-Unit coil fail so as to cause the engine not to run?
Is it a problem to use the transformer I did and the associated wattage?
Any pointers will be most appreciated.
Suamico Pete


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## Big Ed

Hello Pete welcome to the site.









Inside the e unit is a plunger ( the red arrow) that goes up and down it turns the drum. Sometimes the plunger gets stuck in the up and won't drop down because it is a little dirty. 

Before you do anything put the locomotive on the track and gently tap on the shell above the e unit and see if it takes off.

Shoot a little cleaner up in there, I use brake cleaner. After you shoot it with the cleaner blow it out with air.
*Do not *oil this, if you oiled it the oil could make it stick.

Where the wires hookup are fingers that contact the drum make sure you didn't bend any of the fingers when you cleaned it.

2 nice videos all about the e unit.

Part 1




Part 2


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## tjcruiser

Hi Pete.

Good comments from Ed. Expanding on ...

The coil in the e-unit exists simply to raise the plunger up in the air, against gravity, under normal AC track power. When power is turned off to the track (or a reverse button is hit on the transformer, which essentially does the same thing), the plunger drops down (with gravity), and the little "pawl hand" turns the drum wheel to redirect current flow to the motor. Two points:

1. The coil in the e-unit itself is not needed for the motor to run. It simply raises the plunger, but has no direct effect on the electronics of the motor itself.
2. The drum has a four-position cycle: Fwd-Neutral-Reverse-Neutral ... with each full rotation of the drum.

It's possible that the plunger isn't working, and that the drum is stuck in one of its two neutral positions.

However, I'd suspect another possibility ...

The drum acts like a switch, redirecting current flow to the motor. There are 6 copper contact "fingers" that are supposed to touch the drum in just the right spot: 2 above, and 4 below. Often, a finger or two will get bent out of position/alignment, and current can no longer flow properly to/from the motor.

The video shows these fingers. Sometimes, a careful poke at a finger with a toothpick will fire up the motor running, and identify the culprit.

Regards,

TJ


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## Cycleops

Maybe it's waiting for the weekend. No sorry, that was a motorcycle.


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## Suamico Pete

*Thanks*

Being new to this forum - not sure where this will post. I want to say THANKS to big ed and tjcruiser for the great information on E-Units and reasons my engine will not run. The e-unit repair videos are wonderful and a big help to anyone contemplating a do-it-yourself repair.
Suamico Pete


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## tjcruiser

You're aim is spot on, Pete. Post is on target!

Happy to have helped. Anytime!


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## Suamico Pete

*Again a Big Thanks*

To tjcruiser: The tip about the fingers on the e-coil and using a tooth pick worked. It is a really tricky business to get the fingers to have the right angle and pressure to touch the drum, but once I was able to do that the engine ran like it just came out of the box. Not bad for being 60 years old.

I'm please to be part of this forum and hopefully I can pass on a few chestnuts in the future to help someone else.
Suamico Pete


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## tjcruiser

Glad to hear the news, Pete!!!


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