Atlas RS-3 issue (DC)

[carmelmodelrr]

I have three of these (needed for pulling up grades) and they began squealing faintly.  So I took them off the layout to disassemble and lube them.  (I noticed that they are all stamped Atlas 1999)  One of the three now runs well.  One barely runs and the third one won't run at all.  All, however, have lights when I apply power.  I have disassembled and re-assembled them repeatedly without success.  The contact strips are all making contact.  I'm out of ideas (and patience).

Does anyone have any suggestions as to what I need to do to get these locos back in running condition?

carmelmodelrr
Richard Wroblewski

[MK]

Lights on but no go for a DC loco is usually the motor tabs not making the proper contact to the underside of the light board.

When you say that the contact strips are all making contact, are you referring to these or the contact strips along the bottom of the frame touching the truck tabs?

Make sure you check the motor tabs and that they don't get disturbed or deformed when you put the shell back on.

[carmelmodelrr]

The contact strips I referred to were those on the bottom of the frame touching the truck tabs.  I've tried to make sure that the motor tabs were touching, but I'll try again.  Thank you.

Richard Wroblewski
carmelmodelrr

[peteski]

The contact strips I referred to were those on the bottom of the frame touching the truck tabs.  I've tried to make sure that the motor tabs were touching, but I'll try again.  Thank you.

Richard Wroblewski
carmelmodelrr

Sounds like you have this loco (photo from Spookshow's website).


Since you have 3 problem locos after reassembly, I wonder if the problem is mechanical binding, rather than electrical.  The photo shows very easy access to the motor's armature.   Can you freely move the armature?  Give it few turns. Maybe compare how easy it turns to one of your working locos.

If you take the non-running model apart again, and test the motor.  Connect the track output of a DC throttle (or even a regular 9V battery) to the motor contacts and see of the motor runs.  That will determine whether the motor itself is a problem or something else.  If the motor works, and so do the headlights, then the only possible  trouble spot (other than mechanical binding) can be with the motor contacts with the frame.

[wm3798]

Also make sure all the bearing blocks are all oriented the same way.  It actually does make a difference.
Lee

[carmelmodelrr]

If I touch the contact strips on the bottom of the loco with two wires connected to a spare power pack (with the loco fully assembled except for the outer shell), the motor spins like crazy.  But when I put the same loco on the track (no outer shell yet) it just sits there.  ??????

Richard Wroblewski
carmelmodelrr

[nickelplate759]

I have had the contact strips get misaligned which can cause lack of power transmission. Each end of a strip must rest on top of the  metal tab rising up from behind the truck plastic airframe.

[SecretWeapon]

make sure where the contact strip meets the trucks contact(underneath) are clean. it made a world of difference when I cleaned them.

[carmelmodelrr]

Late last night I cleaned the contact strips that rest on the truck tabs.  Then I disassembled the trucks and cleaned the wheel treads as well as the point of the axles.  Then I cleaned the metal truck sideframes with a toothpick on a cloth soaked in denatured alcohol.  (The "holes" where the wheel fits into the sideframes were really dirty.) With all of that done I assembled the loco (but did not put on the shell), then ran two leads which I touched to the bottom contact strips.  The motor turned and so did the trucks.  Then I put the loco on the track and all it did was light--no movement.  I'm running out of ideas. 

carmelmodelrr
Richard Wroblewski

[carmelmodelrr]

OK.  I disassembled the loco again and re-assembled it again--and this time it runs!

So now I have two locos that run and one that I have to work on.

Thank you to all who offered advice.  It's truly appreciated.  Best of all, it helped.  Thank you again.

carmelmodelrr
Richard Wroblewski

[Doug G.]

It's always worth it if, in the end, you see them running on the track.

Doug

[EmdFan]

OK.  I disassembled the loco again and re-assembled it again--and this time it runs!

So now I have two locos that run and one that I have to work on.

Thank you to all who offered advice.  It's truly appreciated.  Best of all, it helped.  Thank you again.

carmelmodelrr
Richard Wroblewski

Do you recall what you did differently on the re-assembly that made the difference?

Thanks.

Steve Woodward

[carmelmodelrr]

I believe the positioning of the motor contact strips--to make sure that they made contact with the frame, was what did it.  I'm experiencing the same problems with the third loco.  I keep re-positioning the motor contact strips but so far I'm not having great success.  But I haven't quit yet.

carmelmodelrr
Richard Wroblewski

[Joetrain59]

Take notes, or photos before and as you disassemble loco. Also, refer to the parts diagrams, to see how parts are oriented.
 And I now mark all motors, when working on them, as to the way they go back in. Top, and front facing just to be sure.
 Joe D