Finally, easy fix for frustrating problem

[K487]

A few days ago I posted this on another model railroad forum, and thought you might find it beneficial here.  Also, it manages to give Bachmann an attaboy or two.
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As I've been helped by many of you on this forum I hope the info below will help you and future forum readers.

First, a brief background reminder of The Problem: Last year I sold all of my HO Athearn BB diesels that I'd been using for about 17 years, and purchased some Bachmann and Atlas Trainman diesels.

Over time I noticed two particular problems especially with the Trainman engines, and posted these on 10-2-10, 10-20-10, and 7-22-11.

Problem #1: The Atlas engines (run in pairs) were making the MRC Tech 2 Railmaster 2400 power pack surfaces in certain areas heat up to too-hot-to-touch temperatures after about 40 minutes of normal running of long trains on flat loops (even though the power packs' circuit breakers never tripped.)  My Bachmann  engines (GP30s, 35s, 38-2s, FTs, SD40-2s and 4 Berks) have never done this.  From some of your suggestions (thank you) I addressed this issue in many ways and, surprisingly, nothing changed.

Problem #2: Ninety eight percent of this problem is with the Atlas engines. After a few months following purchase a pair of these would be pulling a train, then suddenly on their own drop their speed about 60%, run that way for 5 to 40 seconds, suddenly go back to their regular speed, and then every 20 seconds up to 5 minutes apart repeat this. It wasn't a power problem; the headlights stayed at the same brightness level. I tried all kinds of things to address this but no success, and concluded (turned out it was incorrect - see below) that I was over-oiling (Wahl oil) the motor bearings and some of the oil was wicking through a bearing and getting on the commutator plates. After much testing and reading the comments/suggestions/experiences here I decided the problem was in the brush/commutator interface. I then even considered trying to disassemble one of the can motors but continually put that off as a possible last resort.

Well, I finally called a person the LHS recommended for doing railcar painting and decaling. This person had done a super job adding some decals to and painting parts on 3 of my cars, and I hoped he might be able to help. He did - he nailed it.

He said the problem was indeed in the commutator/brushes interface, and that over time "gunk" built up on the brush faces. He had this happen to him and fixed the problem real simply - with Labelle 107 oil.  Here's how.

Just put 1/2 drop of Labelle 107 on the commutator (Labelle even says this oil is for bearings AND commutators) in line with the brushes while the motor is slowly running. This is easy to do through the "air vents" in the motors - no need for disassembling. Then run the motor both ways increasing the speeds (all on the bench). I did so.  [I will add here that it is easier to put a half a drop on a toothpick and apply it - it's hard to see inside the motor and hard to keep steady pressure on the Labelle squeeze bottle to keep a half drop on the end of the needle.  Also if you push the Labelle bottle/needle too far the metal needle may scratch the metal commuator pieces, and wood won't do that.]

I then put the engines (two Atlas RS32s, and two Atlas GP38-2s) back on their trains and have run them, over a period of days, for 6 hours without a single speed hiccup. AND the power packs don't heat up near as much. I AM A HAPPY CAMPER. So far this problem is fixed.

[I imagine the oil dissolves? or ? the gunk on the ends of the brushes, and oils the commutator plates enough for less friction but not enough to cause brush/commutator electrical insulation.]

I'll share an interesting observation. The worst engine was one of the RS32s and I did it first. (As info when it dropped speed it caused its mu'd engine to slow down too, but I never heard any wheel slipping.) After oiling the commutator and running the motor slowly, I finally got it to full speed and its sound (pitch) was interesting. In one of the directions the motor's speed was going back and forth between the old high speed (lower pitch) and a newer high speed (higher pitch.) I let it run figuring it was working itself out, and sure enough after about 20 seconds it finally settled on the high speed.

The irony of this whole situation is that I thought I might have gotten too much oil on the commutator. It turns out that I didn't, but the solution DID require oil on the commutator - not Wahl, but Labelle 107 which is formulated for that purpose.

So, where do I go from here?

First, monitor these four engines for another 5 hours or so of running. If there are still no problems I'll figure they are fixed.

Second, I have one of my four of the Atlas Trainman GP38-2s that's always run slower than the others. I thought it was in the drive train, but when turning the flywheel while holding the engine in the air I felt no unusual resistance. I couldn't figure it out so it's been set aside. Now, I'll bet the problem is electrical resistance  and that it's in the brushes/commutator interface. So I'm going to oil the commutator and test it.

Next, I'm going to start using Labelle 107 on the motor and gear tower bearings of all my engines. It's formulated for that too and I bet it does a better job than Wahl. However, I'll still use the Wahl on the tops of the rails  (my layout is about 18 years old and has never had a bright boy, masonite board, sandpaper or track cleaning car used on it) and other uses.

Then, over the next few months go on a program to use this "oil the commutator" method on all the rest my engines – 8 Atlas and about 18 Bachmann. The Bachmann engines have rarely pulled the "let's slow down, speed back up, and drive the operator crazy" stunt. And even in pairs, pulling the same long trains as the Atlas engines, they have never made the power pack surfaces too hot to touch. 

Lastly, in the "ho engine quiet contest", if Atlas engines are the standard with a grade of "A", then my Bachmann engines (after lubing and some running in) average a B+  -  not bad for their price.

Oh, you might find the following interesting:  I currently have my amp and volt meters on the 3rd loop.  A pair of diesel engines usually pulls about 68 cars (85% plastic wheels, 15% metal wheels) around the loop - 16" radius curves.  The current two Atlas Trainman engines (GP38-2s) show they are together pulling 3/10s (three tenths) of an amp and 3 volts.  When I run a pair of Bachmann GPs (30s, 35s, or 38-2s) they show the same amps - 3/10s - but only 4 volts.  Seems to me they are all drawing very, very little juice for the work they are doing.

K487*

*  My signature refers to the following:  In the early 1970s I worked as an employee of the C&TS RR in Chama NM for 2 years and fired/coaled/watered/ greased that narrow gauge Mike #487 many, many times.

[on30gn15]

Interesting - noted for future use.
Labelle 107 - hmm, is there any on hand?
Yes - have Labelle 108, 107, and Bachmann's 99981 conductive contact lube.

I would think the 99981 would also work.

Have several Bachmann HO engines, diesel and steam.
Don't have any Atlas HO diesels - wait a minute, there are a couple 1980s issue RS-3 buried in the closet. Hmm . . .

[Jim Banner]

I use Bachmann's E-Z Lube Conductive Lubricant, a similar "thinner than water" oil, for the same job.  But I usually use it for restoring old locomotives, the kinds that have sat on shelves for 3, 4 or 5 decades and are now being passed on from father to son or Grandfather to grandson.  When placed on a track, the majority will not run.  Even with power applied directly to their motor terminals they will not run.  If the motor shaft is turned by hand when power is applied, they will often run but poorly.  However, a drop of Conductive Lubricant on the commutator  perks them right up and within minutes, the motors are running smoothly and quietly.  As most of the older motors are open frame, you can actually watch the commutators clean themselves up.  Initially, the copper plates are black from a combination of copper oxide and graphite worn off the brushes.  As the motor spins faster and faster, you can watch the black change to dark brown or even something approaching copper colour.  I suspect the Conductive Lubricant softens the deposited gunk, the brushes scrub it off, and the centrifugal force of the rapidly turning armature flings it into outer space.  It works like magic.

What I have not done is routinely apply Conductive Lubricant to the commutators of motors that are already running well.  Perhaps it is time to select a few locomotives and test them to check results.  My gut reaction is that any oil applied to the commutator will gather dirt and graphite dust.  But then again, that was my first reaction when I heard about oiling rail for better pickup.  It wasn't until I tried it that I was convinced that oiling the rails (very, very lightly) was the best thing since sliced bread.

Jim

[CNE Runner]

Back in the days when I was an avid Lionel collector, I did the same thing as Jim and K487 to recalcitrant locomotives AND operating accessories. As Jim said this process (the insertion of very small amounts of conductive lube) really "perks them up". I have seen a Lionel locomotive, that barely (or didn't) run, go like blazes ('gotta love that Magna-traction) after cleaning out the ~ 50 years of lint and carpet fibers AND lubricating in the fashion mentioned here.

Thanks for bringing back the memory. I have 3 brass 'shelf queens' that no longer fun and will try the conductive lube magic on each...unfortunately the Monks' Island Railway never ran a late 19th century Mogul or Consolidation.

Regards,
Ray

[K487]

ON30GN15:

Thanks for sharing your interesting thoughts and musings.

Jim:

Thanks for describing the conductive oil's visual cleansing process on old commutators.  Also for also describing your use of oil on the rails.  Both of these, in my mind, are totally counter-intuitive.  I remember back when I got my first A C Gilbert American Flyer S gauge train at age 14 (about 1960).  The instructions STRESSED NO OIL ANYWHERE except on the locomotive's two motor shaft bearings.  Took me a while to get that out of my head.

Looks like too it will be interesting while we both (and others?) oil the commutators of locomotives that currently run well.  As you described about old, dead motors, I think the outcomes will please us.

Ray:

You were way ahead of me in oiling commutators, especially Lionel engines with Magna-Traction; I bet they flew around track corners quicker than Superman could ("Faster than a speeding locomotive"?).

Also, if Jim can can use Star Trek approaches on his model railroad (flinging armature gunk into outer space), so can you (do a little time-travel with your 19th Century Moguls and Consolidations.) 

K487