Clean all the wheels.  And thoroughly clean the little phosphor bronze tender truck wipers.  Remove them and thoroughly rub clean with a pencil eraser or something similar.

The wheels, both locomotive and tender, may be made of some alloy that oxidizes heavily fairly quickly.  Moisten a paper towel, very lightly with some goo gone.  Run the tender back-and-forth on that and onto the dry part of the towel, pushing it from side to side to make sure you get the flanges also.  And marvel at how much black crud comes off on the towel. Then, another piece of lightly moistened towel, put it in front of the locomotive on the track and slowly run the engine up on the towel until all the drivers are on it. Then spin the wheels, pressing lightly from side to side and lightly down on the wheels, but not enough to stall the engine. And again, be amazed at how dirty those wheels were. I wouldn't be surprised that if you do this cleaning, it'll solve your problems.

We are talking about a Rivarossi locomotive, but all of the above applies to Bachmann steam engines as well.  Diesels, don't know.I don't have them, and never will.

One thing to remember about model Southern Pacific moguls is that over many long years since the 1960s, there's almost continuously been some HO scale version of it offered. IHC did the last one in the 90s or so but it was a continuation of a fairly crude one offered earlier in the 80s by somebody else. There are lots of them on eBay at any time, but the many crude details and the huge flanges that won't run or anything else except code 100 rail make it not very desirable for anyone really except the train set bunch.

So, I believe there's an opening here for Bachmann to produce a very salable model steam engine. The Southern Pacific was the Pennsylvania railroad of the west coast, and all the way along the southern U S all the way to New Orleans as well. There are thousands upon thousands of SP model railroaders who would buy this engine. And others beyond that who would buy this relatively generic model to convert to something else similar.

An M-4 mogul or a C-9 consolidation.  The present consolidation is a Harriman engine based an Illinois Central prototype, the C-9 was also a Harriman engine. They are very similar. A few detail revisions plus the addition of the medium oil Vanderbilt tender, whic Bachmann used to sell, would make a good C-9.  But the mogul is really what we should see someone offer in plastic. They are similar to moguls formerly everywhere, unlike the present oddball one Bachmann offers. Again, the medium oil Vanderbilt tender would serve well behind such an engine, so all they have to do is make the engine. 

With all of the molecular attention to prototype detail being lavished on the new Pennsylvania K4 and New York Central Hudson, it would be nice to see a real Southern Pacific mogul issued, instead of merely relettering  the present mogul.

Bachmann steam engine tenders have had holes in the tender floor, and other provisions for sound, for quite a long time now.  There are lots of older ones that pre-date the on board sound installation period, before the mid 2000s, they do not have such holes in the tender floor. These engines are seen all the time on eBay, some sellers have enough understanding to photograph the bottom of the tender clearly enough that you can see the holes if they are there. Engines that have the floor holes are referred to as "DCC ready," meaning that the decoder and speaker will largely be a drop-in process.

I always tell people.  Beware of used model locomotives.  You don't know what kinds of abuse they may have suffered. Being run at 150 scale miles per hour for years, being used to brain the little sister, there's just no telling what they've been through. Most people also don't understand that repair parts for these engines are almost always not available. Bachmann is a real exception to this, but few others, good luck, they won't be there.

Jeffrey, your mail trains were nonstop expresses between two of America's largest urban centers. They are bound to be very different from the little plug locals running through the agricultural south that I knew growing up. No.5 was a lifeline to our little farming and oil field community of 15,000, and even more so to the yet smaller towns that lined the route between New Orleans and Houston.

Number 5 was a remnant of a former name train called the Argonaut that had run all the way to the west coast, until the late 50s when it was cut back to Houston, lost its pullman car, and lost its name. After that, the train became an almost entirely head-end car consist- mail storage cars, express reefers, a couple of railway post office cars, and one or maybe two coaches at best.  These mail train stops were the bread and butter of Railroad passenger service, an every day workaday event in almost every small town in the country, until 1968 when the railroads lost their postal contracts, and the ability to financially keep passenger trains above water, which led to the founding of Amtrak, a few years later.

We actually rode Number 5 to Houston a couple of times before it was discontinued, once in the Pullman, while it was still on the train (a story in itself), and the other in a coach with broken air conditioning, attesting to the fact that the railroad was trying to run the passengers off of the passenger train so they could discontinue them.

We called it the mail train.  Because it was, one or two coaches behind lots of head end cars.

I'll never forget the finely tuned dance and workaday drama of the handling of No. 5's mail at the New Iberia depot.  Before the train arrived at 2:12, old-fashioned baggage carts with big spoked steel wheels, some loaded with canvas mail bags and some empty, would be rolled out alongside the track, under the long passenger umbrella shed that is no longer there today. Somehow the agent always got the cart within an inch or two of where the engine would pass.

You'd hear No. 5's readily identifiable smooth distinctive 5-chime air horn faintly float in on the wind from the east.  On days at home we could hear its approach from the house as well.  After interminable moments you'd hear it again, louder now, and you'd finally see the mars light swing into view around the curve at Center Street and enter the paved-over street trackage of Washington Avenue, invariably right on time, rolling beneath the ancient oaks, passing the parish courthouse where ten years earlier the 5-year-old me had watched Mikados stomping and squalling past with westbound freights.

As the train crossed Jefferson Street and negotiated a gentle S curve right before reaching the platform, you'd invariably see that the engine was a single Alco PA unit, classically running out its last miles on a plug mail run, although we didn't know that.  The PA would majestically roll past, slowing, with cadenced bell ringing.  A classic head end consist followed, heavyweight baggage cars with very cool express reefers and boxcars mixed in, steam hissing from between the cars. 

As the railway post office cars smoothly glided by, you'd see the doors already opened with a clerk standing in the door, and others visible behind the barred windows.  Somehow the train always stopped with the open door right at the perfectly placed baggage wagon.  With  precision smoother than any fine classical ballet, the inbound mail would quickly be stacked on the wagon, rolled away, and immediately replaced by the cart loaded with outbound mail.  Just as quickly, the loaded canvas mail bags disappeared into the car. 

The clerk would signal to the conductor that the mail transfer was complete.  In the steam engine days, the engine would have completed water top off at the water column at the west end of the platform.  Since  the few outbound passengers had already boarded the train, the conductor gave the highball to the hogger.  Two airhorn shorts signaled the almost imperceptible start of the train.  Crossing signals sounded for Corrine Street, then Hopkins Street.  The rear end red mars light, suspended from the accordion gate in the doorway of the rearmost car, slowly disappeared around the long gentle curve to the west, passing the barely visible West Tower on its way out, and following the complex pole lines on their westward march.

With the dramatic intensity winding down as the airhorn of No. 5 faded to the west, the carts with the loaded mail bags were rolled to a waiting postal vehicle and the bags loaded for the ride to the post office.  But, like a hidden bonus track on a record, one last dramatic detail remained.  No.2 eastbound, the Sunset Limited, was due at 2:37.  This train didn't stop in New Iberia at the time.  The depot agent walked down to the east end of the platform and hung an outbound mailbag on a mail crane.  No. 2, on the end of its run from the west coast, would often be late but when it was on time you'd hear the airhorn to the west, where No. 5 had gone into the hole ("siding") for the meet, and you'd watch the train regally roll in behind MU'd EMD FP units that always handled the train, the bell majestically clanging a slow tempo. The mailbag would be snagged onboard by the RPO, ending the daily drama of the US Mail coming and going from New Iberia Louisiana.

Oh what a time to be a young railfan there.  We didn't know what we had until it was gone, No. 5 making its last run in late 1963.

I looked at your headquarters on 1400 east Erie Ave on Google earth.

What is the double track railroad that runs down the street in front of your building? The Erie?

The present consolidation has been around for 23 years, so at least that long.

Model railroading today is quite different than that of 25 to 30 years ago or more. Models offered are made in limited runs of various quantities. They come and go and parts inventories are rarely maintained. Bachmann actually is one of the best at it, and for them to not have parts for this model speaks to its antiquity and origins in the Model Railroad Jurassic.

Verily, verily I say unto thee, beware O beware of used model steam locomotives at bargain prices. They almost invariably are what are politely known as a "pig in a poke."

https://en.m.wikipedia.org/wiki/Pig_in_a_poke

I tried asking Mr. Google your question about how much smoke fluid to use, and the answers very widely, so it's not much help. May be a call to the Bachmann Service department would be helpful. They've been pretty helpful to me about other issues in the past.

And there's always the possibility that your smoke unit is defective. If you bought that engine new, and that's the case, they will exchange it for you for one that works. Good luck to you on this. I remember being a kid 150 years ago with a Lionel steam locomotive with smoke and how cool it was.

There are several recordings of that song, made in the late steam era. That one has the best whistle of them all, a Southern Pacific six chime!! My all-time favorite locomotive Whistle!! Really sounds like it Business!

In 1988 I was invited to be part of the staff serving  a tour group aboard three private varnish cars coupled to the rear of the Sunset Limited, riding all the way from New Orleans to Los Angeles and back. It will be the subject of an entire story by itself.  There were many great moments, many exciting moments, and one particularly scary one.

The experienced modelers here will tell you not to use the smoke unit for several reasons. First of all, you can't scale the physics of smoke down from full scale to HO scale. It will always be wispy and look like a cigarette is up inside the locomotive... instead of a real locomotive chuffing hard to pull a train. The second reason is that the smoke from these units is very oily, and after a little time will start settling on everything in the room, in an oily film that's difficult to clean.

Of course, that doesn't help you if your son really wants to see the smoke. I'll have to defer to those having experience with these units to help you there. But, be advised of the two issues above.

Log in, those of you who are old enough to have, in the days of private railroad passenger service in the United States:

1. Ridden overnight in a Pullman car.
2. Eaten meals in a full-service white-tablecloth diner.

I'm working on a narrative of several overnight trips my family took by train in those long-gone days