Atlas Motor Problem

[davefoxx]

Dave,
if you were willing to send me one of those bad motors I could give it a postmortem as I'm curious as to what is wrong.   Of course with the number of projects I have sitting on my workbench it will take me a while to get to it.   But it would be good to find out what happened.

I appreciate your offer to perform an autopsy.  But, one?  Hell, I can send you at least three!  I know I had your address for the M³T, but, if you don't mind, it would be easier if you PM'd it to me again.

Thanks,
DFF

[mmagliaro]

Okay, I confess my curiosity has gotten the better of me about this, because I have never once seen an Atlas (or Kato) motor fail (unless you count one that used to live in an old Kato J3a Hudson I got at a train show with a bad motor).

If you are game, I'd be up for wanting to examine one of these dying motors too.  Send me a PM if interested.

[Rich_S]

Dave, I've only had this sort of thing happen to me with one of my Atlas MP15DC. Thinking it was the motor, I purchased a new motor from Atlas and it seemed to fix the problem for awhile. Then within 6 months, this new motor started getting slower and the start setting on the throttle continued to increase. It reached the point where the locomotive would not start moving until I reached throttle setting 15 and throttle setting 99 was equal to throttle setting 50 on other locomotives. I had a few light boards that would fit the locomotive and I tried running the locomotive on DC. It preformed beautifully on DC, at that point I replaced the stock Lenz decoder with a Digitrax decoder (this is not a plug for Digitrax, just happened to have a Digitrax decoder on hand) and the MP15DC ran like a charm. It seems my issue was not a motor problem, but a Lenz decoder issue.

[davefoxx]

Dave, I've only had this sort of thing happen to me with one of my Atlas MP15DC. Thinking it was the motor, I purchased a new motor from Atlas and it seemed to fix the problem for awhile. Then within 6 months, this new motor started getting slower and the start setting on the throttle continued to increase. It reached the point where the locomotive would not start moving until I reached throttle setting 15 and throttle setting 99 was equal to throttle setting 50 on other locomotives. I had a few light boards that would fit the locomotive and I tried running the locomotive on DC. It preformed beautifully on DC, at that point I replaced the stock Lenz decoder with a Digitrax decoder (this is not a plug for Digitrax, just happened to have a Digitrax decoder on hand) and the MP15DC ran like a charm. It seems my issue was not a motor problem, but a Lenz decoder issue.

Rich,

Unfortunately, I can rule a decoder problem out, because once I swapped the motors, the unit, with the same decoder, became a jackrabbit.  I've definitely isolated this problem to the motor.

Thanks,
DFF

[peteski]

Okay, I confess my curiosity has gotten the better of me about this, because I have never once seen an Atlas (or Kato) motor fail (unless you count one that used to live in an old Kato J3a Hudson I got at a train show with a bad motor).

If you are game, I'd be up for wanting to examine one of these dying motors too.  Send me a PM if interested.

Dave is sending me those motors, but I suppose if he wants, he could send us both a motor or two. 

[davefoxx]

@mmagliaro,

I haven't put them into the mail yet, so PM me your address, Max, and I can send one your way, too!

Thanks,
DFF

[svedblen]

This is getting exciting. Which will solve the mystery first? 

[Ron McF]

When my locos start to run a bit sluggish for no apparent reason I remove the shell, lay the mech on its side on a piece of paper or tissue, and squirt electronics cleaner into the bearings, the trucks, and around the amature. I'm sometimes surprised by how much black gunk gets blasted out. I use this stuff, which comes with a narrow plastic tube to direct the spay:
https://www.jaycar.com.au/electronic-cleaning-solvent-spray-can/p/NA1004

Be careful to not get it on any paint.

After spraying the mech I use a tissue to soak up the excess cleaner, and then set the mech aside to dry out. Once it's dry I lightly oil the mech.

Regards,
Ron McF

[peteski]

This is getting exciting. Which will solve the mystery first? 

Maybe each motor has a different problem?   

[Doug G.]

I'm betting on the shafts expanding, the bearings shrinking, not enough lube in the bearings, too much lube in the bearings, too much carbon/dirt build up on the commutator, not enough carbon/dirt build up on the commutator, shorted windings in the armature coils, open windings in the armature coils, grounded armature windings, not enough brush tension, too much brush tension, too much magnet strength, not enough magnet strength.

I think those are the most likely.



Doug

[mmagliaro]

This is getting exciting. Which will solve the mystery first? 

Remember folks, this is an exhibition, not a competition!

I sent my address.

In actuality, what I'll be most interested in is to see if Peteski and I come to the same independent conclusion.

[peteski]

Remember folks, this is an exhibition, not a competition!

I sent my address.

In actuality, what I'll be most interested in is to see if Peteski and I come to the same independent conclusion.

LOL!  But what if each motor has a different problem? 

Just kidding. Maybe we should also try to synchronize posting of our evaluations? 

[svedblen]

Remember folks, this is an exhibition, not a competition!

Of course. But as an old SW guy I love a good bug hunt, and I'm just thrilled to see how you work this one out 

[davefoxx]

@peteski and @mmagliaro,

Okay, as stated, I have three motors that have been pulled from locomotives over the years.  I lettered them A, B, and C with a Sharpie on the flywheel.  I started with Motor A, which I'm 99% certain is the motor that started this thread.  Since I did not remember exactly why Motors B and C were pulled, I put all three into the same GP38-2 frame that I had available.  Using a Digitrax decoder that was reset to factory defaults, I tested each motor.  After a warm-up of the locomotive with each motor, here was the following results at maximum speed, using my Accutrack II speedometer:

Motor A: 58 smph
Motor B: N/A (see below)
Motor C: 78 smph
For comparison, the motor that replaced Motor A in a U23B goes 124 smph!

Note: Motor B was so bad, that it barely wanted to turn.  This motor is noticeably stiffer than others.  I pulled it off the track, because I didn't want to burn up my decoder, and I noticed that the motor was already warm, despite only being on the track for ten or fifteen seconds.

Since Motor C took off like it was much freer than the other two, despite it's maximum speed being significantly less than the rest of my fleet, I kept this motor, in case a fix is determined by Pete or Max.

So, unless I got the packages mixed up, I'm sending Motor A to Pete and Motor B to Max.  I'll try to get the packages into the mail tomorrow.

Thanks, guys!
DFF

[peteski]

Sounds good Dave!  Could I have motor B, pretty please?  I just fixed a tiny Sagami motor for VonRyan - and it was completely seized!    I haven't given him the good news yet, so keep it to yourself for now.    Just kidding - I'll take whatever motor you send me. 

As far as motor C is concerned, is is possible that there is nothing wrong with it - it is simply the slow-speed motor, as where the 125 Smiles/hr motor is simply the old fast-speed Atlas motor?