Lionel 627 switcher died after cleaning

Sounds as if the staking on the motor that holds it together has worked loose. Can you wiggle the motor casing and does it seem loose?

No loose staking that I can tell. 

After messing with the e unit some more, I now have reverse. The e unit drum rotates with each power cycle, but when I get to forward I get a loud buzz, and a motor twitch, but no movement.

With a set of test leads, hold the locomotive up in your hands, cycle to forward, and while it is buzzing, with your thumb, move the plastic plate on the bottom left and right. It should run in one position. Then place a plastic or metal shim to hold the bottom plate in position. Use a small drop of super glue to hold in place.

Possibly the finger contacts on the e-unit are not making firm contact with the drum. Could be that they got bent out of shape while cleaning, or maybe before it got to you. This is my guess because the motor starts to go, but as soon as you try to draw enough current through that weak connection to actually move the locomotive, it fails. Get it locked into forward, and try (carefully) pressing the contacts against the drum with a toothpick or skewer and see if it starts moving for you. If that is what it turns out to be, you are best off replacing the contacts - I have not had great luck trying to add more tension to them.

This thing is screwy. Now I’m thinking there is a mechanical issue, not electrical. I think the motor is trying to turn the wheels, but it can’t because the small planetary gears between the main gears are loose and jamming the main drive gears. 

I was able to drive it in forward (Motor in front) but when I tried to reverse it just buzzed. If I manually rotated the wheels they felt like they were stuck or jammed. When the gears are in the sweet spot, it will run, but when they get out of sync with each other they jam up. 

Is there any way to fix this? Gotta love eBay, live and learn I guess.

I would take the switcher to a **** good train repairman. Good news is that a post war engine like that can almost always be fixed so it runs great by someone that knows what the hell he is doing, and it usually won't cost an arm and a leg. 

Those gears are 2023-117 idler gears. While that seems like it could be excessive play, I've look at a few of mine that operate well and I could poke at mine and get them to look somewhat cattywampus. With out having yours in my hands, I can't rule out the gears themselves, the pins they ride on, or possibly wide gauge of the main wheels. However, since you admit to opening it up and cleaning it out, I would definitely open it back up again to ensure that the armature ball bearing is in place. This keeps the armature in vertical alignment with the rest of the gear train. It sits just the other side of the truck oil hole. The ball bearing part number is 600-110.

I did not see any bearing on the top or bottom. There was a metal washer on top of the commutator, and a bushing to receive the motor shaft in the bottom near the worm gear. 

I saw another thread on here with a 627, and his washer/bearing on top of the commutator looked plastic, or some non conductive material. Mine is metal, could this be the issue?

The gears are definitely worn out, I got it to finally reverse and I think I could hear them slipping. Forward sounds fine.

Those engines will actually run fairly well even with sloppy spur gears. (I watched your video on the loose gears, they don't seem too bad)  The likely causes of your problem have already been discussed:

1 - e-unit has bent fingers or a dirty / damaged drum - the loco might run with the e-unit drum in certain positions but not others.

2 - broken wire between e-unit and motor - motor would not run at all. Sometimes the wire is broken inside the insulation and looks to be whole.

3 - bad solder joints - same as #2

4 - fouled brushes, dirty commutator, dirty brush holders. - may run poorly, sometimes, or not at all

5 - the only ball bearing is in the lower armature hole. Never seen one missing, but it can happen.

6 - if the motor runs in one direction and just hums in the other, then turn the engine over, and push the black plastic plate from side to side. If the motor runs with the plate pushed to one side, then it is loose.
Lionel recommended dimpling the aluminum frame to hold the plate to that side. I used to use paper matches with the head cut off. I recommend reading Lionel's documentation on this. Here is the write-up, under a different model engine, but the motors are very similar, and documentation applies. Lionel write up.
A number of other interesting techniques have been discussed here. One describes using glue. Sounds interesting, I plan to try that one the next time I run into a motor with this problem.

Thank you sir. I believe the lower bearing area is the cause of my issue. The motor wants to turn over, there is just some kind of mechanical binding going on somewhere. 

I read in another forum where a gentleman had a similar issue as myself with the same engine. His fix was bushing the lower bearing with a pop can wrapped around the motor shaft to fix a worn lower bushing in the plastic housing.

I checked my lower bushing for the ball bearing inside, and it is there. I also experimented with adding and removing shims on the commutator under the brush housing. This had a negligible effect. I then used tin foil wrapped around the lower motor shaft and this seemed to help. I actually was able to get into reverse, although it sounded horrible. 

Today I will try the match stick trick, and also the pop can, if I can find one...I don’t drink soda.

Will report back with findings.

Something else I read in the other thread was about misaligned magnets. I wasn’t quite following what he was talking about though. Here is the quote:

This is a very common problem with that motor style. 'The bound up in one direction' problem is usually due to misalignment of the magnet stack that surrounds the commutator of the motor. The best way to repair it is to drill out the rivets that secure the stack to the frame and carefully realign the stack and re-rivet. Sometimes you can carefully whack the stack into alignment with a hammer. I had this problem with the same locomotive a few years back and sent it to the motor doctor who got it running by making the correct repair.

Is he referring to the horse shoe shaped metal stack that surrounds the armature? The metal plates align with the metal plates of the armature as it rotates on mine. The armature does ride up about a 1/32” in one direction though.

This is a very common problem with that motor style. 'The bound up in one direction' problem is usually due to misalignment of the magnet stack that surrounds the commutator of the motor. The best way to repair it is to drill out the rivets that secure the stack to the frame and carefully realign the stack and re-rivet. Sometimes you can carefully whack the stack into alignment with a hammer. I had this problem with the same locomotive a few years back and sent it to the motor doctor who got it running by making the correct repair.

Is he referring to the horse shoe shaped metal stack that surrounds the armature? The metal plates align with the metal plates of the armature as it rotates on mine. The armature does ride up about a 1/32” in one direction though.


I assume so.
In my experience that is not a common problem. I have almost 50 years actively repairing Lionel and other toy trains.
Did you follow the link to the original Lionel repair manual page describing the problem / solution with a loose lower bearing plate (The black plate between the wheels).

Yes, I did read it. I tried shimming the bearing plate like you described, but it seemed to bind the gears up when I did this. I tried both sides, and both had binding issues. The bearing plate definitely moves back and forth about a 1/16” between forward and reverse. The shaft with the brass worm gear on it also moves about 1/16” back and forth across the bearing plate.

With the armature removed the wheels and gears spin quite freely with no binding. It is only with the armature installed when the binding occurs. 

I tried using a pie tin to wrap around the motor shaft, but it was too thick and bound things up.

I added a small shim to the top of the lower bearing for the worm gear to ride on, and it seemed to help.

when I roll the wheels with my fingers back and forth you can feel them jamming at certain points. It doesn’t do this with armature removed though.

Yes, I did read it. I tried shimming the bearing plate like you described, but it seemed to bind the gears up when I did this. I tried both sides, and both had binding issues. The bearing plate definitely moves back and forth about a 1/16” between forward and reverse. The shaft with the brass worm gear on it also moves about 1/16” back and forth across the bearing plate.

Side to side play on the worm gear shaft is usually OK.
Take out the matchsticks and try using your fingers on the bottom bearing plate to move it side to side under power to find a sweet spot.

 I've seen the misalignment issue on a half dozen or so before I got to my three "junkers". It's likely very slight misalignment from the factory, but from wear now has a less than ideal shape too (tweaked over the years?). I recalled Gramps working on a few and tried.

  Jumping a little power to it and prying the black gear case slightly but firmly, left to right etc. to see if it starts to spin free. Then wedged it that way. We've used fireplace matchsticks (often fatter than shorties/and rough cut, so epoxy grabs well), wedged between the gearbox and frame, sanded or exacto-ed to a light pressure with width, with a little JB weld to hold everything fast. About 5 more years of running already on the oldest, no signs of slowing down.

  Really once wedged, you could fill the wedge side with JBW and remove the matchstick later.

  If your lucky, your JBW will have a high black pigment count. When that happens it can very closely match black plastic in end apperance.

(I've learned I'm saving those darker tubes for engine, tender, and control case repair )

If you do remove the armature again you should be able to feel any spur gear binding that might be present by turning the wheels gently (and maybe quickly too). If its smooth that leaves the worm and armature.

Any kind of lateral shimming of the gearbox binds things up. With the armature out it definitely feels smooth. It likes to drive forward (engine in rear) which tends to push the armature up toward the brush plate. Instead of adding shims on top of the armature I’m going to add a few on the bottom to see if this helps with alignment.

I added some pie tin plate around half the circumference of the armature shaft and inserted it into the lower bearing. This helped free things up a bunch. Will make another video soon of progress. Thank you everyone for the help/tips, keep them coming.

This whole discussion looks sooo familiar. I have had limited success adjusting the black plastic bottom bearing piece, and like others mentioned, I moved it around with the motor running, while held in my hand. Once I found the best spot, I shimmed and CA glued it in place. The other trick I've had some success with is loosening the brush plate just enough to allow it to move slightly, but not enough to provide any vertical movement. Then with motor in hand and power applied, twist the brush plate one direction, then the other and I'm fairly certain you will see a slight difference in both ease of startup, and a higher rpm for a given voltage. Once you find that sweet spot, tighten the screws. That is something I now do every single time when I remove the brush plate.

I have found this type of motor with the aluminum side plates and the plastic bearing plate, to be very touchy as far as making it run well. Even on the best of them, once adjusted for near perfect performance, as things warm up within a few minutes of running, I can detect differences in the ease with which it starts. One of my better runners when cold, will actually stall when hot and trying to pull a moderate load. When it cools back down, back to smooth, perfect starts again.

The same goes for your style with no ball bearing in the plastic bottom plate, but instead has a bushing mounted in the aluminum chassis under the armature -  that style seems to develop excessive side play, which I would guess is due to greater forces applied to the bushing by the worm gear, which is caused by more leverage in the whole motor assembly arrangement.

I understand there is an alignment jig available to help align the brush plate, the field stack and armature, and the bottom bearing plate, but I have not seen one and have no clue how well they work. The older motors like in the 622, 6250, etc., are not made this way and do not seem to have this problem.

And yes, the pinion gears and their little shafts can absolutely be a factor in binding, but they really do have to get pretty bad before things actually bind up - from your video, yours did not appear to be that bad.

he same goes for your style with no ball bearing in the plastic bottom plate, but instead has a bushing mounted in the aluminum chassis under the armature -  that style seems to develop excessive side play, which I would guess is due to greater forces applied to the bushing by the worm gear, which is caused by more leverage in the whole motor assembly arrangement.

I don't think any of the 44 ton switchers were made with the bearing (bushing) in the plate between the armature and gearbox. If it has the original motor, the plastic plate at the bottom should be serving as the lower armature bearing.

CW, you're probably correct, I have never worked on a 44 ton switcher, so I was interpreting his comment below:

I did not see any bearing on the top or bottom. There was a metal washer on top of the commutator, and a bushing to receive the motor shaft in the bottom near the worm gear.

He probably meant the "bushing" was the armature well in the plastic plate bottom piece. My mistake.

After two days of putzing with this thing, I finally have good news to report...kind of. It works reliably in forward with the e unit turned off. I’ve tried a million different shimming combinations on the bearing plate and armature and can not get this thing to reverse without locking up. 

I will leave it like this and keep an eye out for a replacement gearbox/ motor assembly. Does the 44 ton switcher share a motor/gearbox with any other models? Will anything else drop in as an upgrade? 

Thank you again for all the help, wish I had more time to mess around with it. Here is a video of her on the tracks.

Just an update on my 627. I swapped a known good e unit in today, and also resoldered all the motor joints. It did not solve the problem. Will keep an eye out for for a good used power truck.