Author Topic: Troubled loco help  (Read 2127 times)

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mecgp7

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Troubled loco help
« on: March 27, 2014, 06:37:15 AM »
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I have a brand new Atlas GP38/40, etc. chassis from one of the very latest releases. DCC ready, gray motor. The issue is that it takes huge amounts of power (full throttle) to get it going, but once it takes about two trips around the layout the power required to keep it at the same speed is reduced by half. After a few trips it operates just like any of my other Atlas locos. In fact it is one of the quietest and smooth running chassis that I have.
The question is why? I have tried everything that I can think of including checking trucks, drive shafts, swapping out the light board, yadda, yadda. It's in the motor as alone, when cold, it still takes a lot of juice to get it going. When it warms up it runs perfectly. Does anyone have any thoughts? I did lubricate the shafts coming coming out of the motor thinking that they may be binding, but it had no effect.
I'm at a loss.
EDIT: She has had numerous miles of.constant running so it isn't a breaking in thing. Even after long runs, once it gets cold the process starts all over.
« Last Edit: March 27, 2014, 06:45:12 AM by mecgp7 »

jamesk3142

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Re: Troubled loco help
« Reply #1 on: March 27, 2014, 07:19:34 AM »
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I had something similar, But, Not exactly it turnout to be a bad bearing block. With the motor out holding the bearing block see if it spins freely. I had feeling it mite of over heated and deformed it. Easy to swap them out to at least elimint them from the picture. JimK 

johnh35

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Re: Troubled loco help
« Reply #2 on: March 27, 2014, 10:00:40 AM »
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Maybe it's time for new brushes? Once it is warmed up, is it still slow from a stop?

lock4244

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Re: Troubled loco help
« Reply #3 on: March 27, 2014, 01:49:00 PM »
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I have 3 x GP38-2 that have been doing that brand new from the box. Also, a number of C628 and C630's do the same (5 or 6 iirc)... I just figured that the C6** line were yard loafs, but it doesn't seem to be isolated. I've been mulling over starting a thread on this because I'm really starting to question the quality of Atlas locomotives. I was told by a dude in the LHS that it's caused by the lubricant that they use at the factory, which may make sense except the recent pair of GP9's and one I've picked up don't have any issues. I assume they all come from the same factory... perhaps that is incorrect?

John, once they warm up the seem fine, and the lights function normally on DC, as power increases the lights get brighter, so to me it's not an electrical issue.
« Last Edit: March 27, 2014, 01:51:54 PM by lock4244 »

garethashenden

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Re: Troubled loco help
« Reply #4 on: March 27, 2014, 02:48:26 PM »
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To further confuse things, I have an HO Bachmann 44 tonner that does exactly the same thing.

mecgp7

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Re: Troubled loco help
« Reply #5 on: March 27, 2014, 03:21:28 PM »
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Maybe it's time for new brushes? Once it is warmed up, is it still slow from a stop?
Hi John,
I haven't checked the brushes, but even if it was them, would it act that way?

I ran the motor out of the chassis and it still does the same thing when cold. I can't figure it out. I'm gonna' burn my house down as it takes full throttle to get it going!

peteski

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Re: Troubled loco help
« Reply #6 on: March 27, 2014, 04:33:32 PM »
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It could be muck (a highly technical term) on the commutator, misaligned (binding) motor shaft or bearing or sticky oil in the bearings (which loosens up  after a warmup).  Or maybe something else. 

If I had the motor, I would give it a thorough cleaning in my ultrasonic cleaner, then check the commutator and the bearings.  If all looked ok, I would then oil it sparingly (using light oil) and put it back in the model.
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rodsup9000

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Re: Troubled loco help
« Reply #7 on: March 27, 2014, 04:37:45 PM »
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This is a shot in the dark, but if the motor causing it, I think the brush springs are too strong. When it is cold, the springs have a lot of tension on the brushes and thus it needs a lot of power to overcome the friction. Once it has power running thru the springs, the heat lessens the strong tension on the brushes (weakens the springs) and it runs like it suppose to.

Rodney
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johnh35

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Re: Troubled loco help
« Reply #8 on: March 27, 2014, 05:36:47 PM »
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Clint, my first thought would have been the motor shaft bearings being too tight except that performance was acceptable up until recently. When the motor is cold, does the flywheel take more effort to turn versus when it is warmed up? Probably hard to tell since the amount of friction should be minimal to begin with. If it is tighter when cold, maybe some of the bearing dust has worked its way into the space between the shaft and bearings and creates the problem until the motor warms up and the bearing I.D. expands? Never have seen this before so it could be any number of things.

rodsup9000

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Re: Troubled loco help
« Reply #9 on: March 27, 2014, 05:47:48 PM »
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If it were the bearings, I think the lube would of helped, but he said it didn't.

 Try this, using a drill or Dremel spin the shaft for a bit. Then hook power back to it and if it starts like it does when warm, it is the bearings then. If it doesn't, I think it's the brush springs.

Rodney
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mecgp7

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Re: Troubled loco help
« Reply #10 on: March 27, 2014, 07:47:56 PM »
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Problem solved. It was a broken brush. A small piece of the brush had actually gotten inside the motor. I can't explain why it affected the performance like it did unless each time that I started the motor it had to wear down the broken piece. It didn't prevent the motor from turning but it did bind it a little.
I sacrificed a brush from an earlier motor. Does anyone know where to get brushes for Atlas motors?

Thanks to everyone for the advice and feedback.

Power Stroke

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Re: Troubled loco help
« Reply #11 on: March 29, 2014, 05:38:57 PM »
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Hmmm. Brand new locomotive, and a broken brush? Just how new? New to you but used.  New, as in, it's 20yrs old and has never been run, or literally " I just bought this from a HS" new.
Not terribly impressed as of late.
I am really having a hard time understanding why these have any issues at all, and find it unacceptable at any price but especially if your paying full boat for power.
If your power was truly new, you should not have to replace brushes in order for it to operate properly. How is it any different from your expectations when buying anything new?
Just a thought.

peteski

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Re: Troubled loco help
« Reply #12 on: March 29, 2014, 05:44:08 PM »
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PowerStroke, if you look at the initial post, it states She has had numerous miles of.constant running so it isn't a breaking in thing. Even after long runs, once it gets cold the process starts all over.

What wasn't mentioned is how many hours of running this started happening after? The loco might have been new at some point when it was purchased, but it might have had lots of running time before the failure occurred.  That was not clearly stated.
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Power Stroke

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Re: Troubled loco help
« Reply #13 on: March 29, 2014, 06:19:08 PM »
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PowerStroke, if you look at the initial post, it states She has had numerous miles of.constant running so it isn't a breaking in thing. Even after long runs, once it gets cold the process starts all over.

What wasn't mentioned is how many hours of running this started happening after? The loco might have been new at some point when it was purchased, but it might have had lots of running time before the failure occurred.  That was not clearly stated.

I missed the edit, my bad.
Even if there were "miles" of continious running, it still seems unacceptable. However, with that type of description, it really isn't brand new, is it?
As a service manager for a commercial Ford truck dealer, and a technician with 20+ years of experience, I find the term "new" used quite often, only to find that "new" means "new a year ago" or 10,000 miles ago.
Either way, as dirt simple as new Atlas locomotives are, there really should not be any issues, as long as it is handled and maintained properly but unfortunately there are.
Based on what I have seen from the O/P, I am fairly confident that he takes care of his equipment, so it seems like a QC concern to me.

Bendtracker1

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Re: Troubled loco help
« Reply #14 on: March 29, 2014, 07:19:03 PM »
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Does anyone know where to get brushes for Atlas motors?

Well it's good that you figured it out!
As for new brushes, Atlas should have those available, either on-line or with a quick phone call to their parts department.

"If you would like to place a parts order, please call us at 908-687-0880. You can also fax us at 908-851-2550 or email us at parts@atlasrr.com with your order if your credit card number is on file."

Otherwise there's at least one seller on eBay who has or had some, note these in the link may be for KATO or KATO made ATLAS brushes, but I've seen some listed from him before, not sure if they are interchangeable or not;
http://www.ebay.com/itm/MOTOR-BRUSH-SET-KATO-and-KATO-MADE-ATLAS-N-SCALE-/351036822540?pt=Model_RR_Trains&hash=item51bb6cd40c