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I want to explain the situation with these transformers, then have a few questions. Hope you can take the time to read through this. Always enjoy the advice from this forum.

Decades ago, I inherited lots of Lionel O gauge items, including one each of a type R and V transformer.  I have a PW ZW that I use for track power and some accessories, but needed another transformer for accessories only on a layout I am building, so I put the V into service.  I did some cursory updates: new face plate, greased upper gears, cleaned upper coil and carbon rollers, etc, but did not access the lower coil. In order to do that I had to remove heavy wires from their lugs, and did not want to jeopardize the unit with my limited soldering skills. All seemed fine, except that when I engaged the AU circuit, the transformer began to overheat, so I quickly turned that circuit off and did not use it.  For several months all worked fine on the other 3 circuits, until last week. I must have nudged the knob on the AU circuit, b/c suddenly the unit began to smoke, overheat, and emit a terrible burning odor that pervaded the entire basement. I quickly shut down the circuit and unplugged the unit. Had to remove it from the house b/c of the odor.  

After it cooled, I opened it up to take a look. Upper unit looked fine, but all I could see for the lower unit was that the carbon rollers were not rotating when the knobs were turned and the arms holding the rollers seemed discolored.  I debated on removing the soldered heavy wires to access the lower unit, then decided to hold off.  After a few days, I put the transformer back in service, and although the other circuits seemed fine with no overheating, the odor reappeared, so I had to again remove the transformer. 

I then turned to the R transformer.  I had previously replaced the face plate thinking I would sell it, but now needed it to operate the accessories.  Opened it up and did some minimal cleaning.  Seemed in good shape.  I was about to attach bus wires for accessories to it, then realized I had to put it in phase with the ZW first.  So here are my questions:

For type V:

1.  Is it worth attempting any repair?  Should I remove the heavy wires to access the lower unit? 

For the type R:

1.  Given that it does not appear to have a single "common ground" terminal, is it possible to put it in phase with the ZW? If so, which terminal should I use on the R unit to connect to the common ground on the ZW? (see photo)

R termnals

2.  Is it possible to continue to use the single bus wire I have for ALL track and accessories with the R unit, or do I have to use different ground wires for different levels of fixed volt output, as well as both variable circuits?  If I must use different ground wires, how does the effect phasing with the ZW?

Final questions: Should I seek another transformer entirely for the additional accessories besides the ZW?  If so, which one? I really do not need the modern high-end units for my accessories, but I do need a unit that can provide different voltage levels for different accessories, of which there are lots of vintage Lionels, like the lumber loader, log loader, sawmill, coal ramp and loader, milk car, cattle car, rocket launcher, 2 magnetic cranes, bascule bridge (actually, it's the modern version), lamps, gatemen and crossing gates, 13 switches, 5 UCS tracks, and 5 bumpers (switches, bumpers, and UCS tracks powered separately from track power). 

Many thanks for any advice,




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  • R termnals
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Wow!! Sounds like you got a lot going on....first thing is lamps draw a lot of power...especially if you have all your switches on fixed voltage plugs. I can’t say for sure with out seeing your V type as to what happened to it, but it sure sounds like it’s shorted somewhere inside.....if your not confident about exploring around inside, then don’t...have a professional take a look at it....(afraid of a little fire scarecrow?) far as the r goes, with all the stuff you got that pup’s gonna cook like a popcorn kettle tryin to keep up....from your list (and maybe I’m wrong) sounds like you need 2 more 275watt ZW’s....or perhaps a MTH Z4000, I think you need to spread this load out a bunch more.......let’s see what others have to say too.....fortunately Postwar ZW’s have gone by the wayside and can be had a whole lot cheaper these days....even rebuilt units ready to rocknroll............Pat


Thanks for your comments. Yes, the short was definitely internal on the V unit.  Frankly, glad I was in the vicinity, or could have had a true disaster.  And yes, plenty going on...and only in a 9X14 room!  There is a half wall on one side, so viewers can see the operation without being in the room.  So far, anyway, it's all working.  Here's how it goes.

I have 3 main lines: 2 on the ZW and one powered by an MTH Z-500 with the inexpensive DCS remote commander to power a Rail King unit with Protosound (did not want to spring for the full blown DCS unit;  everything else is either TMCC or conventional).  Even when I have 2 mainlines in operation, one is on the ZW and the other is on the Z-500.  They all work fine. 

All switches and bumpers are on the BU circuit of the ZW and work fine at 14v. I am now connecting the lights and seeing how they function as I keep adding them. They are on the CU circuit of the ZW.  So far the brightness looks OK, but not finished so will see if the one circuit can handle this.

For nearly all of the accessories, they are only intermittently operated (can't work them at same time!!), so I thought the voltage draw would be manageable:  1) the gatemen and crossing gates were on one of the circuits of the V unit, 2) the accessories operated by controllers (log loaders, cranes, etc) were on another circuit, and 3) the UCS tracks were on a 3rd circuit.  This allows me to vary the voltage to each unit as necessary (not needed for gatemen/crossing gates). 

I have to admit, while I have been checking the operation of each item as I add it, I have not had this layout in full operation (trains plus accessories), primarily b/c I can not manage all this and the grandkids at same time. So this might keep the power draw manageable at any given moment on the transformers. 

I noticed the wattage on the R unit is 100 as compared to the V unit which is 250, so as you point out, the R unit may not be able to handle this load.  If I must go with another transformer, I have seen many refurbished ones at train fairs.  I trust a good ZW, but do not need the whistle and directional features for the accessories, so wondered what other units might work.  Another V unit just might do it. 

Still need some advice on connecting the R unit to this system, and if that is even possible. 

Thanks again,



First on the R transformer:  I put it in service, phased it with the ZW, and used only the 2 variable voltage circuits, one for all the lights.  Works fine, but did heat up quickly.  I then realized I had 2 bus wires for the lights, each going in different directions on the layout. I then split them up, one with the ZW and one with the R unit. Both units still heat up, but manageable.  I refinished a dozen vintage #58 lamps, and although they draw lots of current, they look great. (see photo)

#58 lamp

Now to the "V" transformer:  First of all, it's really a Z transformer!  Don't know why I cited it as a V in the earlier posts.  Sorry for error.  Well, I decided to open it up and get into the bottom of the coil and the A/B circuits.  Got the rollers to spin, cleaned the coil with DeoxIt-D5, soldered the heavy wires back in place, and plugged it in while still open.  No smoke or short.  Tested each circuit and output fine through entire spectrum. Did notice that the A circuit does need an extra push to make sure it's off.  That may have been the cause of the internal short, combined with what appeared to be contact of the arms on the A and B circuits. I adjusted them to be sure they were separate throughout range. Took photo of the coil that must have overheated with the prior short (see below).  I put it back in service and watched for any overheating or odor.  Was alarmed when saw a slight billow of smoke, to opened it up again. Nothing seemed wrong, so I suspect the little bit of smoke was from the DeoxIt-D5 burning off - or at least I hope that's the case.  There still is a slight odor, but nothing like before.  I will attend a Great Train Show event in late January outside of Seattle and may look for a refurbished unit.  Need power for accessories.

Thought I would share this latest and greatest.  Any further thoughts or advice welcomed. Hope your holidays are great!



Coil on Z unit


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  • Coil on Z unit
  • #58 lamp


Yeah, the lamps look great after I sprayed them with original paint color from Henning's Trains.  Look terrific in a classic Christmas scene I intend to create.  Even my wife approves!  If the current draw is excessive, I thought I may have to replace them all with LEDS, but I would prefer not to go that route. I wonder if tear drop bulbs come in LEDs.  That shape adds to the look of the lamps. 

I am familiar with problems with original cords on old transformers, and did replace it on my ZW, but believe it or not,  this cord looks fine.  The indentation in the cord in the photo is where it runs through the wall of the unit, so not so unusual.  If I open it up again, I may as well replace it.  At the very least, I'll replace the plug.

Thanks again,


I would replace the rollers on the Z. You got through the hard part of getting into it. Also, I would check the circuit breaker out - it should have tripped in under 10 seconds. The Z-22 circuit breaker is available from a few of the traditional parts suppliers. You can also "upgrade" to a modern BUSSMANN 19115 breaker.

In addition, the classic transformers shouldn't continually be expected to deliver over 75% or so of their total rating, so about 180 Watts for your 250 Watt Z transformer. Can't hurt to get some amp meter readings to ensure your loads are not too large.

Thanks for additional advice. Just checked circuit breaker and it tripped in about 3 seconds.  Not sure it would have tripped in the original issue, as the short was somehow internal.  In any event, from past experience with sensitive units running on TMCC, I have learned (the hard way) to protect any modern motorized units with fast acting breakers and TVS units on all my main lines and sidings.  I do not have these for the accessories.  

Yes, I should have replaced the rollers on the A and B circuits, but after cleaning, they appeared to function decently. Replaced them on my ZW many years ago, and I recall it was not easy to get the rivets back in place.  One thing I did not mention above - it appears that the Z was previously serviced. Some wires were not the original and the rollers on the C and D circuits had been replaced.  

I notice a slight odor remains with the Z, and this may force me to abandon it.  That one coil for the A and B circuits was apparently really fried.  Just want to make it through Christmas day when all the grandkids will be over to operate all the funky old Lionel operating accessories. 

Thanks again,


Michael, I can’t help but to think you are simply just taxing these units to their max.....especially when it comes to incandescent bulbs, they are just simply power hungry. As BMORAN4 has stated, you can only expect 75% of the advertiesed power these units produced. You need to spread this load out. As you pointed out yourself, you got a lot of stuff happening.....and a lot of bulbs....and even what you have hooked up to your ZW, sounds to me like you may be taxing it as you have a local train shop that can assist you with some more power for your layout? I know you say you’d like it ready for the grankiddies coming, and believe me I’m with ya, I’ve got 2 coming Christmas Day too....and the baby girl does not tolerate or allow my Christmas cookie payment could be in jeopardy.....and I know that R type has to be screaming, as I mentioned before....don’t mess with that Z, especially if you don’t exactly know what’s going on inside, I’m not knocking your abailities, or your knowledge, I’m just trying to keep you railroading and enjoying’ve got to spread that load out, another ZW or maybe 2......they are not too bad a price these days....if you were in NC and driving distance to me, I’d lend ya a couple to get you by.........your transformers are simply screaming....and the Z was the first to go “poof”...............Pat

Thanks for the continued advice.   Let me begin with my comment on the "coil". Shows you how much I know about this stuff.  Best to refer to the photo I posted earlier.   I was referring to the item on the left half of the "coil and laminations assembly" (as identified in Greeberg's Repair and Operating Manual for Lionel Trains, p 587).  Not sure if this is the secondary coil, or not, but that is what looks fried in the photo.  I suspect the odor comes from this item when it heats up.

And yes, the lights are creating a serious load.  I have lots of operating accessories, and they have been in service for months without any real heat from the ZW or Z.  I would guess that's because most of the time, only one is in use at any given moment.   Before I began adding the lights, the only items in continuous operation were the switches and bumpers connected to the ZW: 11 OLRs and 2 022s, plus 5 bumpers, set at 14v.  No serious heat from the ZW. 

The heat started when I began to add the lights over the past few weeks.  I was wondering how this would go, so kept an eye on the ZW, which had all the lights.  Yes, it heated.  But then the meltdown occurred on the Z, which had nearly all the accessories, and no heat.  When I first put the Z into service, I noticed heat, crackling sound, and a serious dim in the green light one time when I turned the knob on for the A circuit. I suspected an internal short, so did not use that circuit.  Then the "meltdown" occurred suddenly a week ago.  I must have nudged that knob. Even though nothing connected on that circuit, the Z was smoking badly and stunk.  I shut all circuits down, unplugged the unit, and had to get it out of the house b/c of the odor.  So this event was from an internal short, not an external draw. 

In any event, all the incandescent lights will continue to pose a hefty load. So alternatives appear to be are more power with the lights broken up into manageable sections, or perhaps switching to LEDs.  As I noted above, I repainted the #58 lamps and they look fantastic.  I also have about a dozen refurbished vintage 71s, which are also incandescent.  My preference is to keep these, so I'll be on the lookout for more power.  This will be for accessories only, so don't need whistle or directional controls. 

Until I secure additional power, I can keep the draw down by disconnecting some/all of the lights, or maybe spreading the load among the ZW, Z, and R units.  This will get me by the holidays and all the fun with the accessories.  Will certainly consider the suggested power units.  Thanks, Pat, for the offer, but NC is a bit of a distance from Portland, Oregon!  I have seen lots of refurbished units at train fairs (been to York several times; link this with visits to family in NY), so will see what is available on line, at local train shop, or at the fairly big show in late January outside of Seattle. 

I'll keep you posted on the eventual solution. Thanks again, and Happy Holidays all!



To resurrect this old thread:

I just picked up a type R with the intention of using it for a little Standard Gauge fun. 🙂

It came in the original box which, although kinda ratty, did its job well, so the unit itself is in very nice condition... including the cord! All the posts check good as labeled.

It's rated at 100W, so I guess this means it's late pre-war(?); anything in particular I should know about before I begin using this very neat old thing?

Mark in Oregon



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