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@woodsyT posted:

How many of the postwar locomotives have been reissued with a DC motor? all of them? or just a few favorites?

Not enough of them, IMO.  Let's count:  726 / 736 Berkshire - yes, LionChief Plus.  That's about the most direct example of a postwar loco upgraded with the best of today's technology.  2046-style large Hudson: not really.  (The LC+ Hudson is a different mold with more prominent domes.)  2055-style Hudson: sort-of.  The LionChief Pacific shell is a close approximation, but I would HAVE to tone down those shiny wheel rims!  Also, there's no provision to install the boiler front with the Elesco feedwater heater, so the 2065 is still MIA.  746 N&W J: This was done in RailKing with PS2/PS3.  681 Turbine: This was also done by MTH;  the smaller of the two RailKings is closest to a Lionel 681.  773 Hudson: The Vision Line 11209 has a lot more detail, and it's really expensive.  The Williams version looks like a 773, but it's a lousy runner inferior to the original.  224 Prairie: The closest surrogate to this might be a RailKing "USRA" Pacific without the feedwater heater (it came both ways.)  (The RailKing variation with the Elesco feedwater heater could be a stand-in for the prewar 225.)

The 675 / 2025 / 2035: Lionel did briefly offer these in plastic(!) with a can motor and DC only operation.  This was hardly an "upgrade."  Since these were supposed to be a Pennsy K4, you could argue that the RailKing and LionChief Plus baby K4s would be the modern choice to haul your O27 Pennsy varnish.  Still, not quite the same styling.  Skinnier boiler, more like an S-gauge model on an O gauge chassis.

The 2-4-2 Columbia / Scout and four-wheel switchers like the 1615 HAVE been redone with can motors, but as far as I'm concerned, Lionel's efforts were a low-cost hack job.  These ubiquitous train set locos with a transversely mounted 8008-series can motor run smoothly when pulling a load, but their speed is all over the place when running light on a layout with sharp curves.  For "hands-on" operation I would rather have a Pullmor!  Recent posts discussed how this low-quality can motor doesn't respond well to speed control upgrades.  As a surrogate for the four-wheel switchers, I nominate the MTH Premier 0-4-0s, although to make it look like a postwar piece you would have to remove much of the add-on detail (horrors!)  The K-Line A5 which was later offered by Lionel, is too big IMO, especially if operated alongside other "traditionally sized" locos mentioned in this post.

So the Columbia / Scout, the loco that most of us started with, has NEVER been reissued with a quality drivetrain.  Every year I hope Lionel will invest in an upgraded mechanism that would bolt into older models.  Even Percy's 4-wheel chassis (from the Thomas lineup) got a worm-drive makeover at some point in the last 10-15 years.  Unfortunately he lacks a flywheel, and his plastic chassis can't easily be installed in a vintage 2034.

The last one I can think of is the O27 Prarie, which began life as the 1666, and ended its AC run in the 1980s as a 4-4-2.  My favorite Postwar locos were the beefed up Prairies and Adriatics beginning with the 2026, 2036, 2018, etc.  In the late-'80s Lionel hacked a small, transverse can motor into the 6-wheel chassis like it did with the Columbia, and to pretty much the same result.  I owned one of these, and left it in the box to run my original 2026.  It was a noisy runner with a lot of cogging and notchiness at slow speeds; I can't imagine that a Cruise Commander would help.  I really wish Lionel would offer this unique body style again with a quality LionChief Plus 2.0 drivetrain.

Whew that was a lot of writing!  You may not agree with all of it.  But my point is: The vast majority of Postwar steam locos HAVEN'T been reissued with can motor, speed control, etc.  So if we want an idealized version of our childhood icons, it's left to us to somehow upgrade the performance of the originals.  The sad thing is, it SHOULDN'T be that hard to offer a retrofit because ONE four-wheel chassis, and TWO six-wheel chassis would cover the gamut of the above locomotives.

Last edited by Ted S

I have upgraded some postwar and MPC locomotives to tmcc and that works well.

While not an electronic trick, the universal "Pullmor" motors themselves are redone with ball bearings. Here are a couple of pictures.



This is a 2321-100M motor used in Train Master locomotives. Ball bearings really improve motor performance.  The ball bearings significantly reduce internal friction of the motor from that of the oilite bushings.  Reducing friction results in smoother rotation and lower amperage draw. Ball bearings also gets rid of the coffee grinder vibration of the motor and so the motor is quieter.

The top ball bearing is 1/8 inch inner and 1/4 inch outer diameter.  It is really important to get the top ball bearing centered. The bottom bearing is 3/16x5/16 while the middle is 5x11 mm.

While the ball bearings update the motor from a 1930s design to more modern standards, the motor is still limited by its obsolete 1930s design.  These limitations include the flat face commutator, three rotor and two stator poles, and small motor brushes.


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  • 20231121_214925
  • 20231121_214954
Last edited by WBC

Thanks @WBC!  I would love to know more specifics about the Pullmor ball-bearing conversion.  Would you please contact me privately?  (my email is in my Forum profile.)

@woodsyT I addressed the O27 switchers in my lengthy treatise above   Lionel has been making 'em like the 18054 for almost 40 years.  It has the same motor-chassis used in their low-priced train sets.  It starts and runs very smoothly if you're pulling a load.  Ironically for a cheap switcher, it's also ok on really wide curves.  But something about the design--perhaps the wheel gauging, or the friction from the rubber tire, I don't know...  When you run just a loco and tender on an O27 oval, it reluctantly creeps through the curves and then speeds up unrealistically to ~35-40 mph as soon as it gets on straight track.  The drivetrain just lacks the sense of mass and gravitas possesed by a postwar 1656, or even the MPC-era 8506.  So IMO, not better than the original  

I triple-dog-dare you to buy an MTH Premier 0-4-0, remove some of the add-on detail, and repaint it to blend in with your postwar fleet!

Last edited by Ted S

After tinkering in the basement this last friday & saturday I think I may have came up with a 'kit' of components that helps an ol' Pullmor behave better - but, as I knew going into this, it doesn't help a lot. But I did come up with a circuit that improved the pullmor motor low-speed behavior and limits the 100+ scale MPH top speed.

Across the brushes, I tried a wide range of resistor values starting with a wire-wound 0~10 Ohm, 25 Watt rheostat. I tried adding and removing non-polarized 1uf, 50Volt capacitors (recommended for RF noise reduction) across the brushes & coil frame. The resistor seems to mildly increase low speed torque (but I might be seeing what I want to see). I tried adding and removing the different values of shottky diodes in-line with with the supply to the motor field. I also tried adding and removing shottky inverted-pair diodes in series with the supply to the brushes only. I moved the shottky diodes and resistor so that both had a chance to be first in the circuit, it didn't appear to make a difference. I tested using Two MPC's, a Lionel 8471 NW2 switcher & 8550 NJC Geep, and two different Pullmor-ed Postwar motors and one loco/frame motor - a Lionel ATSF 616, a 2035 loco with strong magnetraction, and a dual motored NYC 2344.

At first I was attempting to video each step or each A~B comparison with a plan to edit them and all that, but my A.D.D. got the best of me and a lil' frustration with the soldering iron had me get out a project testing breadboard on a flatbed with alligator clips and several wire jumpers - this way I could set up 'the testing board' and just interrupt the wire leads to each locomotive in the test. so, I'm sorry about the lack of video. After finding what appeared to be the 'best' circuit setup I experimented to see if any loco liked a different resistor rating. They all seemed to like 3.6~5 Ohms, so I started using the 4ohm 10watt ceramic resistors I have. Lower ohm ratings increased the amp load at the transformer and severely limited top speeds, higher ohm loads only provided slight top speed limiting. The diodes seemed to make the biggest difference in motor behavior.

My outer loop is roughly 55 ft long - or roughly half a scale mile. Before the circuit was added the lowest lap speed (without stalling) was about 50 seconds around, or roughly 35ish scale MPH. please check my calculations, I wasn't keeping perfect notes and huffing solder fumes (just kidding about the solder fumes) When I timed the slowest non-stalling speed around my track after using the 'circuit' the best one got down to 15ish scale MPH or 120 seconds moving steadily (more or less) around roughly 55 linear feet pulling a 1 or 2 pound dumbell on a flatbed, depending on the locomotives pulling capacity/capability.

It decreases the top-speeds of all the locomotives to what appears to be something like 75~80 scale MPH (I am just guessing, I didn't calculate this) - but it is still looks quick enough that it can cause derailments over switches and tight curves - at least they no longer have that lightning speed that guarantees a locomotive launching. It also noticeably reduced the 'jump start' behavior that most pullmor motors give you at take-off AND the take-off speed was noticeably smoother and a bit lower, but it is NOT like the low, realistic 'creep' or 3~5 scale MPH and smooth-momentum start these modern command-control locos give you.  This circuit uses a little more current than the motor(s) alone - My analog ammeter would bump from showing roughly 1.8~2 amps and it would bump up to 2.3~2.5 amps while using the circuit and pulling a 1 or 2 pound dumbell on a flatbed on gargraves track. The double motored locomotive moved from 3.6~4 amps up to 4.2~4.5 amps. Remember, I had the locomotives pulling a flatbed holding the testing board the weighed maybe half a pound, plus and a flat-wheeled postwar flatbed with a 1~2 pound dumbell balanced on it. The 2344 NYC F3 had the lowest and steadiest speed around the track. The single motor locomotives needed more throttle attention to avoid stalling than the dual motor 2344 NYC. This also supported gunrunnerjohn's prior point that dual non-synchronized pullmor motors waste a fraction of their effort while allowing the locomotive to run a bit smoother/steadier as a result.

I have coarsely diagrammed the circuit in the pic below. I have what I might describe as a width of knowledge about electrical stuff and electronic circuitry, but I would hesitate to indicate that have any real depth of understanding about why this works.  I have decades of on the job electrical/electronic experience with little schooling in this subject. I also suspect that the circuit will warm the coil/frame up a little bit more since the resistor leaves more current available for the coil - and I wonder if the motor brushes and commutator plate are being asked to work harder too. Maybe greater minds will advise me/us...?

PLEASE NOTE: I also have not performed any sort of long term/stress test yet. In the coming weeks I will to try and run a locomotive for an hour or two non-stop to see if the performance changes or something overheats and/or releases it's "magic smoke". This circuit would be very difficult to squeeze into a postwar steam locomotive body if it could be done at all.

circuit [4)

EDIT: - picture uploaded. please share ideas/concerns. I will try to perform a longer (1-2 hours test) soon
- and I want to thank everyone for their input/wisdom/critique/etc. I wouldn't've known where to start without you.

2nd EDIT: Houston, I think we have a problem. at 15 minutes run-time the resistor was up to 390 degrees fahrenheit or almost 200C. I think it's back to the drawing board! This isn't bad for the resistor (yet), it's bad for the plastics in our choo-choos! This is burn your finger, melt your train shell hot. NFG! Do not do this to your train!


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  • circuit (4)
Last edited by woodsyT
@woodsyT posted:

circuit [3)

Wow this is great info!  Unfortunately (at least for me, on a PC with Chrome browser) your circuit diagram didn't come through.  Since I wouldn't know a Shottky diode if someone served them as a side at Thanksgiving dinner, please try again.  In addition to the schematic, a couple photos of the assembled circuit (even if it's just on a breadboard) would be very helpful.

Your results are promising.  It sounds to me like the performance improvements are significant enough to merit the modest effort required by these mods.  And in any event, they are easily reversed.  Thank you, thank you!!!

Last edited by Ted S

Pics from the 'kit' installed on my 8471 Pennsy Switcher.

The 8471 has less pull power than the 2333 NY-F3, but they both had almost the same 'kit' time around the track. A dab of hot glue is holding the resistor on the metal plate.

EDIT:  Houston, I think we have a problem. At 15 minutes run-time the ceramic resistor was up to 390 degrees fahrenheit or almost 200C. I think it's back to the drawing board!   This is burn your finger, melt your shell hot. This is not bad for the resistor, it's bad for the plastics on our trains! NFG! Do not do this to your choo-choos!


Images (4)
  • 20231127_094351: Resistor and diodes
  • 20231127_094330: Motor plate and capacitors
  • 20231127_094200: Wiring, resistor and diodes
  • 20231127_094142: The 'kit' under the hood
Last edited by woodsyT

I wonder whether a proper heat sink would address this issue?  I've seen some pretty elaborate heat sinks on integrated circuits that have spikes more than an inch tall!  Heat isn't necessarily a problem, shedding it safely is.

The resistor across the brushes acts as a by-pass, reducing current flow through the armature relative to the field.  Since the performance improved with the resistor, it also makes me wonder why the armature wasn't wound with a higher resistance at the factory?

I have Bob Hannon's book on motors which contains detailed measurements of resistance for most of Lionel's motor types.  Usually the resistance of the armature is higher than that of the field, but the values vary pretty widely.  I recommend this book to all, it's fascinating to learn about how these work!

Last edited by Ted S

I'll look up that book.

I was asking a lot of that resistor, as evidenced by the rapid temp rise, my resistor rating/value was a bit low, I'll get a few others and see about managing heat with a better sized resistor accounting for coil/armature readings.

The positive:

The locomotive(s) lowest speed without stalling were measurably lower for all of them. There also appeared to be improved torque at lower RPMs - making slower running speeds possible while pulling weight. Jump starts were gone.

The non-positive: 🙄

It uses more current/juice/amps from the transformer.

The resistor was a significant heat source. I pulled out a couple HVAC tools to read the temp because I could feel warmth as it passed me on the track. Hot as a frying pan.

I'm gonna read up a bit, get some different value components and start again from zero👍 maybe I'll get lucky. 🤞 I was pleased with what I found out so far.

Last edited by woodsyT

I have several dual DC motor locomotives that run too fast on the layout and was impossible to get them to run decent at a low speed. Examples are the D&H RS-3, amd my Alaska Alco. I re-wired the DC motors to be in series rather then parallel. They run much smoother now, but at a lower speed. In this video, the first locomotive is my Alaska which was modified and you can see how it runs on the layout. (it is conventional)

I'm not an EE.  But I can read Dale's (R.I.P.) drawing well enough on my computer screen to see three components:  a 500-ohm variable resistor(?), a 2N4922 transistor(?), and a 2N4919 transistor(?).

Generally the technique of wiring motors in series is used with the ubiquitous DC "can motored" locomotives.  I would guess that the components prescribed in Dale's circuit are optimized for these motors.  I don't believe I've read about series wiring being applied to locos with universal "Pullmor" type motors.  Then again, if no one else has done it, it might be interesting to try!

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