I have a 726 Berkshire from 1946 with motor issues. This loco has the 726M-1 motor in it. I cannot get the motor running. This a large stack motor with the large armature. It was running last year, but, not this year. I replaced the brushes and springs, cleaned the motor, and commutators. Lubed and oiled the motor. The gears and armature move freely. I wired it up correctly. I think the armature is shot or shorted out somewhere. How do you rewind an armature with new wire? Is there someone I can send the motor to for repairs? Thanks.
I would just buy a new armature. Way easier and cheaper. Jeff has some, but you will have to find someone to install it.
Did you try it not wired to the E-unit? Does it hum or do anything…
You think my local hobby shop could install an armature for me? They are pretty good at what they do. How much is an armature from ttender.com? What is the part number? Thanks.
If not theres a guy in Baltimore I send My trains to that probably can as he also works at a major train store part time repairing trains. If you need his info send me an email thru the forum with you email address in it.
Lionel armatures are pretty bulletproof. Are you sure you don’t have some other wiring problem or a problem with the e-unit? Are the fingers on the e-unit making contact with the drum?
Earl
Can you give us a little more info on what the engines does when you apply power to the track? Does it hum, headlight come on, does the e-unit work or move?
A little more info could save you some money!
If you have an ohmmeter, you can put it to across the comutator contact surfaces. You should get equal readings if the armature is good. I don’t know exactly what the readings should be. I just look for equal readings. I get near zero readings if it means anything.
Yes, My headlight comes on, E-Unit hums. My contacts and wiring is all good. I think I have a short somewhere in the motor. I dont have an ohmmeter. Think I have a dead section in my communtators. Not sure what to do. I have a spare motor, but it is smaller than this one. But, is a 726 horizontal drive motor, just doesnt have the large field assembly or large armature. I put it in and the loco works just fine. But, I would like to have this bigger motor in it and keep it original. Thanks.
You can get a digital multimeter at Harbor Freight Tools for like $4.99 and they are OK for occasional toy trains use. You really should have one anyhow.
Is it an all-in-one tool?? What does it read?? Volts, ohms, the whole deal?? Thanks and I will look into getting one.
If the Armature was “Shorted”, I would look for lots of heat and smoke, maybe a transformer trip. The windings will be dis-colored, the Armature will need to be re-wound or replaced.
If the Armature is “Open”, then look for a broken wire, most likely where it’s Soldered to the Commutator Plate.
I am pretty good with my hands and a soldering iron gun. Could you tell me how to rewind an armature?? I know there are 3 sections of where the wire wraps around. Then they are soldered to the commutator plates. But, what order do the wires go in or whatever? Is there a website that tells how to do this?? thanks.
You really need to find out if the armature is bad first. As others have posted, read the resistance across each of the commutator plates. If the resistance readings are all about the same, the armature is probably OK. If one of the resistance readings is open, the break is almost certainly at the connection to the commutator plate. If one of the readings is a short circuit, check for debris in the gaps between the commutator plates. Clean out the gaps between the commutator plates and retake you resistance readings. If there is still a short, the armature is bad.
Rewinding an armature by hand is very difficult. The problem is making the windings tight enough and close enough together so that when you get the proper number of windings on the armature, the windings don’t exceed the normal footprint of the armature and contact the field magnet. If you still attempt to do the rewinding by hand, it is important not only to get the correct number of windings but to make sure they are wrapped in the correct direction and the ends are connected to the appropriate commutator plates. It is not impossible, but it is quite difficult. It is much easier to just buy a new armature, if in fact, the armature is really bad.
Earl
To add to the post above, the armature also needs to be re-balanced after winding. I would call Jeff at The Train Tender or keep an eye out on ebay.
If you’re not getting alot of heat and smoke I would doubt that the armature is to blame. Make sure the armature turns freely and then look at the brushes. Make sure they’re actually contacting the commutator and not hung up in the brush hoods. Also, check the ground wire from the field winding and make sure it’s pegged nice and tight to the field stud.
Good luck
Jim
Okay, I cannot seem to find a used large stack armature anywhere. Jeff at ttender.com does not have one listed in his parts. I dont know where to begin to look elsewhere. Oh well, might just have to use the other smaller motor and save me the time. Thanks.
You seem absolutely convinced that the armature is bad but you have never reported doing any of the tests that have been suggested in the above posts.
Earl
I checked the ground wire from the winding on the top of the motor, it is secured and tight. What could possibly go wrong with a motor, they are very simple motors. The brushes are not hung up in the brush tubes. They are indeed contacting with the commutator. I have brand new brushes and springs. I cleaned the brush Plate and still motor wont turn over. I tested the motor with out the E-unit and it still does not work. The male plug thing is wired up right and is in the left hole on the back of the motor. Gears are not binding up, they mesh nicely. Only thing i can think that is wrong is the winding on the armature is somewhere broken or came disconnected. I still dont have a multimeter. Thanks.
Can’t you test the continuity of an armature just by using two wires connected to a transformer, and checking for a spark when you touch adjacent segments of the commutator?
Martin
I dont know, never tried it. Dont think I wanna do that. Sounds dangerous. Thanks.
Although you seem impervious to suggestions to test the motor, I will make one recommendation and then leave this thread alone if you don’t want to take it.
Disconnect the motor completely from everything else. Wire the field coil and the brushes in series. Connect the series combination to your transformer and give it some voltage. If it doesn’t run, then you have isolated the problem to the motor. This means that either the armature or the field is the problem.