Smokeless Steam Engine - Causes?

I have a Lionel B&O 4-4-2 Atalantic (6-28004) that used to smoke like crazy but has now stopped. It’s been upgraded to Railsounds and Command Control (CC). Runs well in CC or conventional modes. Smoke lever appears to be operating. What’s most likely cause(s)? Thanks!

  1. Loose wire or incorrectly wired smoke unit.

  2. Smoke unit switch or TMCC turned off

  3. broken/burned out smoke unit

  4. Too much smoke fluid

I like Door No. 3.

Steamcrazy, If it’s not a busted wire (or frayed due to heat from smoke unit), then the smoke unit has likely bit the dust.

My oldest modern era 4-4-2 is now 16 years old. I recently replaced the smoke unit. the original was still working, but there was more smoke coming out from the sides of the decorative cast-in shell cylinders than through the smoke stack. Turns out when I pulled the loco apart, that the original smoke unit had warped.

These smoke units are made of plastic and while I suspect it is a plastic that withstands heat better, it’s still plastic and when you’re putting 8-16 volts of power to the track, well it seems inevitable that sooner or later these smoke units will fail. I’ve noticed most of my other DC can motored locos use far less current than do these 4-4-2 steamers, especially under load of a train.

I have another older postwar unit that I rebuilt and added a modern smoke unit to. That has run fine for the past 9 or 10 years, but the smoke unit just stopped working on it the other day. I suspect that one is burned out. As a comparison, I’ve had Seuthe brand smoke units in a couple of steamers and seldom get more than a year out them, so I’ve given up on the Seuthe ones. It’s also critical to use the Seuthe smoke fluid with the Seuthe units as the liquid smoke is more refined for the more sensitive Seuthe units.

Jeff Kane (the Train Tender) usually stocks these smoke units. He’s a great parts guy to deal with. The smoke units are not terribly expensive to replace and it’s not that hard to do.

I have no idea whether or not you can actually repair these modern plastic smoke units the way you can some of the postwar ones.

The two most common causes we find are: the smoke unit switch turned off; and 2. the smoke unit turned off using the CAB-1. Sometimes a TMCC reset is all that’s needed or a reprogram in case the wrong codes were used.

I’ll ask the simple question no one has mentioned yet.

Did you blow down the stack to make sure there was no “bubble” preventing the smoke from leaving the stack? That can happen a lot too, especially if it’s an “it worked yesterday(or 10 minutes ago)” situation.

Good Luck.