Has anyone replaced the resistor in a Lionel TMCC smoke unit to improve the smoke output?

do not believe the main board can handle a different resistor. if you change the resistor you run the risk of burning out the board.

I have been down the same road as you and could not find confirmation that this or a similar switch of resistors actually works. I was going to try it in a TMCC steamer I have but after working put how much more current a 16 Ohm resistor puts through compared to a 27, I decided not to risk frying the SMU board or maybe even the main board.

On another forum, someone suggested putting two resistors on a TMCC unit in the way that MTH units have but I don't think that idea was followed through either.

I think that one of the repair wizards who post on this forum ought to be able to say whether altering the resistor in either of the above ways could work. I'd certainly like to know.

I will note that my super-smoking Legacy steamers use a single 8 Ohm resistor and I think one (FEF-3) uses a 6 Ohm, but these are really very different smoke units from older TMCC ones of the kind that Mike R.'s video concerns.

Lionel has available a 20 ohm resistor. You might try just this one. A 6 or 8 ohm would fry the electronics and resistor in short order.

Jeff T.  I have replaced the Lionel smoke resister.  Measure the resistance of the smoke resister and then go down 10% or less.  I had a TMCC Challenger and the resister was 27 ohms.  I replaced it with a 24 ohm resister - a 25ohm would have been better.  MTH level max smoke.  I also drilled out the air input to the fan to the inside diameter of the fan,  Changed the rotation of the fan so the blades swept the air toward the air outlet.  The die cast outlet for smoke from the smoke unit was restrictive so I drilled it out until I had a very thin casting that fit to the smoke unit.  If I remember correctly the smoke unit had 12 volts in normal smoke and full track voltage on the boost mode - so the limit is overheating the resister.  I used wire wound ceramic resisters which I never had a failure.  If you are close to the Detroit I sill have a selection of resisters.  I tried a MTH smoke resister - 14 ohms -  and had fire out of the stack!!

I have a mth one in my NYC Niagara with no issiues and i run it a ton.. I have some 8 ohms in several tmcc engines with no problems..

I think Lionel offers 6, 8, and 27 ohm WIRE wound bare resistors. They also offer a few ceramic coated versions in their starter set engines. I think 24-25 ohm would be a good alternative in these units if they were also bare wire wound but I have not been able to find alternative sources. Does anyone know of place that offers them? I've checked the usual suspects like Digikey and Mouser to no avail.

Pete

I've wondered whether an MTH smoke unit would work in a TMCC engine (not Legacy). I have one old TAS smoke unit, which very closely resembles a standard MTH unit, that came with instructions for installing it in a TMCC (RS4)system. I inferred that an MTH for Lionel SMU swap was possible but jojofry's post above is the only one I have seen recording practical experience of this - assuming of course that he uses it in TMCC mode rather than conventional.

Is it simply a matter of plugging the MTH unit's wiring into Lionel's SMU power and board outlets? 

I use legacy i just took one out of a ready to run mth smoke unit did the bigger hole and stuffing .. ..Shes smokes now ..I have at least 4 hours on it

Thanks for all the comments! A little more searching and I found the post.

The resistor switch in the TMCC fan driven units was done by Rod Stewart. Rod swapped the 27 ohm OE Lionel resistor for a 16 ohm MTH resistor.

I emailed Rod earlier and he reports he has done several of his older smoke units with no issues whatsoever and "excellent" results.

I made the trip to my LHS and picked up two of the MTH resistors for 75 cents each. I was on my way out of town so now I have to wait til the weekend to fog the house!!

Once I'm done I'll add a note as well.

I hunted around too and found this comment by Marty Fitzhenry, which is very interesting:

"The MTH smoke unit uses two heaters [resistors].  The Lionel system uses one.   More is better in some cases.  The smoke fan motor that Lionel and MTH uses is the same part.  The impellers will interchange.  The recent Lionel locomotives do smoke very well.  The most common smoke resistors used by Lionel are 6 OHM and 8 OHM.  I have with great luck taken Lionel engines that use an 8 OHM element and put 2 MTH elements in.  The MTH elements are 16 OHM and when connected in the unit read 8 OHM.  Same as Lionel."

More possibilities here!

I found that note as well. Obviously, i hope, Lionel beefed up their boards for the resistors they are running in the new engines. I was concerned about going from the 27 ohm to the 16 ohm in my older engine til I heard from Rod.

Going to a 6 or 8 just might be more than our engines can handle. I'll play with the 16 and see what happens!!

I'd be interested to know what you find when you try this. I have some TMCC engines from around 2005 where the Mike Reagan treatment has produced some improvement but they are still not a patch on MTH. If swapping out the resistor works I'd try it.