New Smoke Unit for JLC Legacy Big Boy

What’s wrong with the smoke unit?  May need just a rebuild.  New wicking maybe a new fan motor, take the sleeving off the heating resistor.  Adding John’s super chuffer would help big time.

This is a relatively early Legacy engine, and a like-for-like replacement of parts may not be possible. Things like AC voltage regulators and control board codes have changed over time, and I have found that trying to match up parts from what’s available now leads to a high failure rate.

You might want to search the forum because I recall that smoke issues about this particular model have been discussed in the relatively recent past. The smoke unit used in it was a particular kind of 6 Ohm model installed in a number of locos from the period around 2008 that  (1) is no longer available (I checked the Lionel replacement parts page) and (2) was problematic because of the strain put on the AC regulator. Lionel eventually recommended replacing the stock 6 Ohm resistor with an 8 Ohm one.

BUT Gary is right - it may only need a smoke unit tune up depending on exactly what issues you are having with it. If you are able to do that yourself, that’s the best way to start.

If more extensive work is needed, in your shoes I’d send it to an expert. Or get GRJ’s guidance on whether a SuperChuffer kit will work with this engine. The engine is both old and unique enough to merit an expert eye.

So....here's what happened:   Knowing the wick had never seen fluid, I put in 20 drops of JT Mega Steam.  I let it soak in for about two minutes.   I then added 10 more drops....and fired it up.

The smoke unit was anemic at first and was just barely starting to "work".  I let it go another lap and the marginal smoke output decreased.

I called it a night.  Came back the next day and turned it on.  No smoke.  Added 20 more drops.  No smoke at all.  Went around for another lap.  Nada.  I then blew out whatever fluid that may have puddled up with compressed air and cleaned up the mess.  I've since turned the smoke off via the remote.

And that's all folks.  Really like the locomotive, FWIW.

Berkshire, I turn mine off also. Not worth the hassle. I will rework them and put GRJ’s product in my ERR conversions and once I know they work then off they go. I don’t use any of my Legacy smoke units. What a shame. I’ll bet most of the returns back to Lionel are for smoke units.

First off, if you actually want it to smoke, you need to determine where the issue is.  Since this has the analog smoke unit, there's really nothing major that needs to be "replaced" unless it's gone wild and burned it up.  I'd start by changing the smoke resistor to an 8 ohm unit and installing new wick.  The resistor should be about 1/4" from the PCB, and project straight down in firm contact with the wick, but NOT totally buried in the wick, the top of the smoke resistor should be clearly visible!  While you have it open, thoroughly soak the new smoke wick, it'll take 40 or more drops of smoke fluid.  Reassemble and test.  If you still get anemic smoke, my top suspect is the smoke regulator, they're notorious for crapping out.

The smoke operation on these is pretty simple on these units.  This is actually a model that would benefit from the Super-Chuffer, it is the same vintage as my 10-Wheeler, it really shines with the Super-Chuffer.  I even made a special version for Legacy locomotives.

I believe this is the wiring diagram for your locomotive, the smoke fan is driven directly from the chuff switch, so it has no smoke at idle if the chuff switch lands on wrong spot.

John:  I may now have two Legacy Steamers for you to fix.  

As always, you are a gentleman and a scholar.  Much thanks!!

If work allows, I'll try to dig into this in the next week.  If not, I've been waiting to send John a first version Legacy Santa Fe #3751 for while....I just haven't had the time.  That will be a little more problematic, me thinks.

I really appreciate all of the input and help, fellas.

@romiller49 posted:

Berkshire, I turn mine off also. Not worth the hassle. I will rework them and put GRJ’s product in my ERR conversions and once I know they work then off they go. I don’t use any of my Legacy smoke units. What a shame. I’ll bet most of the returns back to Lionel are for smoke units.

I actually like the heavy Legacy and MTH smoke....to a point.  But when my smoke unit wasn't working, I didn't see the point in continuing to run it.  So I just turned it off in order to run the 4014 w/o worrying about any further damage.

A few years ago, John converted an MTH 614 to TMCC for me and added the Super Chuffer.  Very cool locomotive now.  (I wonder if anyone else has a 614 with TMCC since Lionel is yet to make one.  The Third Rail 600-614 C&O units are hard to find....but I digress.)