Reply to "Smoke unit doesn't chuff"

Well this isn't going to make you happy. I've recently worked on a number of failed Lionchief and Lionchief Plus based smoke units.  Verifying in the parts diagrams, your engine uses the same new "legacy" style smoke unit. Here's the issue, the smoke unit itself is not the fix. The problem is the tiny surface mount transistor that drives the fan and would chuff has failed into a constant on state. The problem is, that failed part is buried on the smoke daughter card of the Lionchief board, not on the cheaper and easier smoke unit itself.

Meaning, either you find a tech willing to take that apart, take the board stack apart, replace the transistor, assemble and solder the boards back together, and then put your engine back together or send it off to lionel, or buy if you can replacement pars and that part is not available. And it could be your fan motor ran dry on lube in the bearings, thus making it draw more current (I've actually heard one squealing brand new) and that's what could have blown the transistor.

https://www.lionelsupport.com/...a5-a7e7-7c570474a91c

Again, the fault is actually on the mainboard and is causing the fan to be constant on. The chuff also comes from the same mainboard, so it knows it's chuffing- but again the failure mode is either the transistor fails stuck on or fails off and never turns on. I've seen both.