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TMCC CP F3 set has one Pullmor motor that acts sticky or balky, moves a fraction of a turn (motor armature, that is) and sticks.  Unit is virtually brand new.  Ran fairly well for 15 minutes or so and then started this balky/stalling behavior.  Cannot see anything amiss with brushes/springs, wiring.  What to look for?  Motor issue, or motor driver portion of the TMCC board?  Thanks for thoughts.

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So it’s from 2002, ….that’s kind of a far cry from virtually brand new, …..rule out all the simple possibilities first, check that the grease hasn’t gone to concrete, look for broken wires, etc. …sometimes stiff older wiring can break right at a solder lug, but stay put, and even make a connection sometimes…..also, wires can break inside the insulation, and not appear broken, ……do a wiggle test while running to see if you can duplicate the complaint……you’re dealing with 20+ year old wiring,….anything is possible,……


If the motor moves a fraction of a turn and sticks, I would look for debris jammed in the spur gears on the side of the power truck.  You can even try turning the problematic motor's armature by hand one pole at a time.  Don't force it.  If there is a mechanical bind, you'll feel it!

Pat's advice to check for hardened grease is sound.  The binding could also be caused by a split worm wheel in the truck block.  If you separate the motor from the truck block to regrease, wipe some of the old grease off and look closely with a bright light for any hairline cracks.  Good luck, and please post back with what you find.

Last edited by Ted S

Thanks, all.  With all our can motors, I forgot the basics of dried armature bearings after 20 years.  Two drops medium light oil bottom and top on all now.  The jam turned out to be the magnetraction having picked up a sliver of some broken metal from between the ties, and that jamming the gears on the one truck.  I removed motor and checked grease in the slowest-running truck/motor and the grease is still in great shape.  The board heat sinks are just comfortably warm after 10 minutes running in on rollers.  Still at it, amp draw gradually coming down.  In conventional mode, exactly 1.25 amps per motor now, still running.  Wires are good quality, still very soft even with age.

Any comments on how many minutes or hours of running in motors of this vintage need to get as smooth as they are going to get?  I don’t have much experience with them.

@cnwdon posted:

Any comments on how many minutes or hours of running in motors of this vintage need to get as smooth as they are going to get?  I don’t have much experience with them.

@cnwdon posted:

After 45 min+ running in, in each direction on rollers, smoothed out.  Then pulled ore drag as intended and the only problem is the lack of cruise control, not available for AC motors, so that's the way it is. 

Electric Railroad (ERR) makes a unit called the AC Commander that can be installed with TMCC AC motored engines (i.e., those with Pullmor motors), which will make them run smoother, and will provide additional speed steps for significantly slower speeds. Next best thing to cruise control for AC engines. Running TMCC engines using Legacy also improves running characteristics of these engines.

Regarding breaking in Pullmor motors, they typically continue to smooth out with age. You indicate you have rollers. You could probably run them repeatedly for hours (with occasional breaks for cool-downs) and it would continue to break them in. Older Pullmors with years of operation run very smoothly.

Glad you found the problem.  I would just run it normally and regularly a couple of times per week.  Make sure to vary the speed and direction so that the gears wear in over a wide range of service conditions.  I second Breezinup's suggestion of an AC Commander.  A fellow named Mossback Mike has been posting about some tests of AC-motored locomotives.  He's documented that the usable voltage range is pretty narrow, so along with a proper break-in, having more speed steps (and setting the stall correctly) will get you better performance.

Mike's conventionally-controlled 2333 F3 managed to throttle down to 5 scale MPH.  That's about as good as any can-motored loco can do!

Don, maybe you could post a video of how your loco runs with the stock electronics, once it has a little break-in time.  I was personally never impressed with TMCC1.  Setting the "stall" speed helped make best use of the 32 speed steps that were available, but the vagueness of the CAB-1's big red knob made for more "remote" and less control.

If you're lucky enough to have a CAB-2, using an ERR AC Commander in R100 mode should give you better control.  Ultimate performance will depend a lot on how well-sorted your drivetrain is mechanically.  I'm a big believer in optimizing the mechanical system FIRST before throwing electronics at it and hoping for a miracle.  Good luck, and I look forward to that video after she's had some track time!

Thanks, Ted.  Separate from the electronics, the narrow voltage range for controlling Pullmor and other open-frame AC motor loco speed is a big problem for me.  Even with stout power supplies (MTH Z4000’s and a Mainline Industries “The MAX” from years ago) a four motor lashup pulls the source voltage down from 19 to 15-16.  That is before any voltage drop on the longish trip through 12 ga buss wires and many short 16-18 ga power drops to the track, which adds 1-2v drop despite the heavy wire.

I just put a post on the Digi-Key forum asking advice for finding a suitable AC to AC voltage regulator that will preserve the 60 Hz sine wave, take 22 or 25 volts as its input (Z4000 or The MAX), and put out a stable 18-19v with any load 0-15A.  How tall that order is, I don’t know for sure.  I’ve read that AC voltage regulators are not cheap, so haven’t pursued up to now.  Considering all the ERRCo boards I might wind up paying for, and the time to install all of that, the price of the voltage regulators may look reasonable after all.  Will post what I learn.

Because Lionel's gears are back-driveable, two 3-pole motors can jog each other as they're about to stall.   So there's a definite gain in pulling power AND smoothness by having two Pullmors instead of one.  Just ask GRJ about his Phantom ;-)  But four pullmor motors is almost overkill, and a definite amp hog.  I'm not sure that one ERR Commander can even handle 4 motors, you might need two Commanders (which doubles the cost of a proposed upgrade.)

As far as a power supply, Right of Way made a 400-watt transformer circa 1990.  They're rare and pricey now, but you can easily duplicate it with a set of 24v industrial transformers wired in parallel, their primaries controlled by a 15A "Variac" (toroidal autotransformer.)  You'll have to add  your own whistle / bell controller, and be sure to use appropriate circuit protection!

I'm not sure if you found Mossback Mike's posts.  The biggest issue he cited re: narrow voltage range, is a loco going too fast and leaving the track with more than about 11V on the rails.  You have the opposite problem.  Once your loco is properly broken in and adjusted, you should be able to enjoy a wide range of speeds from about 7 to 20 or more volts.

Be careful though.  Lionel threw some performance away by limiting their Legacy / LC+ electronics to an absolute max of 19V.  Heck, the Postwar ZW (which was kind of a quasi standard) went up to 20V, and the Prewar Z to 24 volts!  G scale also has an informal standard of 24 volts, and LGB trains with their Buehler motors run very well even without speed control.  If Lionel's electronics weren't so limited in terms of headroom, performance gains could be obtained in some locos by swapping in a 24V motor, and supplying up to 24V through the decoder from the rails.  I know this, because I've already done it!

Last edited by Ted S

Thank you for continuing to put thought into solutions.  That Mainline Industries unit is an “industrial transformer” type unit, probably very similar to the old Right of Way unit.  It doesn’t even get warm in service.  I suppose there are larger industrial versions that could improve the problem, as you suggest, but regulation of the voltage would be the optimal solution.

The need for four motors has more to do with keeping traction tires on diesels pulling long trains, from personal experience, anyway.  Sharing the load with matched units seems to avoid stretched and thrown tires.

The 19 volt limit for Lionel boards is top of mind.  If I have the option, would like a regulated 18.5 volts.  No replies to DigiKey post so far, but I’m sure there are smart folks out there who will have some info to offer.  If I could zero out the voltage variation at the point of output from my TIU channels, so that only the small line drop under load remained, I suspect performance would be much better for these locos.  As you know, the TMCC system delivers a proportionate motor voltage based on the track input voltage, so even if it performs in a stable way, the train will slow when the track voltage drops with AC motors.

Like you I’ve put a good deal of thought and time into the problem over some years.  Coming to voltage regulation has taken years.  We’ll see what’s out there.

Starting a new thread about voltage regulation with this same post:

Have had no luck finding a low voltage ac full sine wave voltage regulator device.  However for an industrial transformer option, here is an interesting possibility with a $980 price tag for the enclosed version, about $200 less if you buy open and make your own enclosure for it.  The key spec is an output voltage drop of only 0.8v at full 15a load when the output is set to 20v (would be ~same at 19v.)  Curious about other manufacturers/sources/prices if someone has knowledge.

Product link:

Link to technical specs which include V drop at various output V settings (see “1510” Type in table):

Thanks for the comment.  Have asked Timko for pricing.  Two of their motors plus an ERRCo Cruise Commander board kit, plus my time to install or a pro’s labor and shipping, would be the price per dual motor diesel.  I have enough such locos plus others with DC motors but not cruise control needing Cruise Commander M, that the time and convenience advantage for the industrial transformer might make it a better bargain.  Am I missing something else?

I think you're trying to make a silk purse from a sow's ear.  I can't see sinking that kind of money into a garden variety F3 with a single Pullmor motor.  For $200-250, you can routinely find nice dual-motored TMCC F3's.  The single Pulmore motored stuff that Lionel turned out usually were pretty anemic pullers on a good day.

I actually added a motor to the Lionel Phantom and then used the ERR AC Commander to enhance it's electronics.  I have to say, that turned it into a totally different locomotive, it easily tripled it's pulling power and gave it much better low speed performance!  However, this isn't a model you can just find a dozen replacements for, so for me it justified the time and expense.

Improving the Lionel Phantom Locomotive

@cnwdon posted:

Thanks, John

FYI the immediate reply from Timko:

”The DC motor replacements are $45.00 plus shipping. They work in any Lionel steam with horizontal pullmore motors”

So not costly but also not for diesels..

It would be good to ask him again and specify that you want can motors for converting vertical motored pullmore diesels. He probably does not get a lot of requests for those since most trains have can motors these days.

Not really sure where you are going with the AC voltage regulator idea, but it does not sound like the kind of thing that would work.

If the concern is low voltage spots on your track, fixing the connections or adding more power drops will cure that. An AC voltage regulator on the track power input will do nothing to fix low voltage track sections.

Last edited by RoyBoy

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