Should the Legacy Lionmaster Big Boy #4006 (6-11149) smoke fan run in neutral and if not can it be modified to run in neutral?

You need the super chuffer II.

That's it's entire job- it smartly with a microcontroller, runs the fan and determines when idle (no chuffs) VS Chuffs.

https://ogrforum.com/topic/74354735402263739

Again, the issue is you have what is known as a semi-smart smoke unit which cannot natively smoke at idle.

Additional tips: Your stock smoke unit board on the smoke unit ONLY controls the fan. It has nothing to do with the resistor other than being a connection point. Thus, the resistor and it's value are all about what smoke regulator- a separate PCB are setup for (8Ohms is the recommended value).

You measuring 10 Ohms is expected between meter tolerance (measuring low resistances) and the temperature of the resistor at the time of measuring (increases as it gets hot compared to cold resistance).

@Vernon Barry the Super-Chuffer II (designed by @gunrunnerjohn) came to mind but I have two questions.

1) Is noted above in detail, briefly restated here:  Is there a way to know if this Legacy engine should be running the fan in neutral or if it does indeed stop in neutral?  So I don't know if what I have is a symptom of an issue or if I do indeed have a 'semi-smart' smoke unit which cannot smoke at idle.  I have had a number of issues with this engine and I want to make sure it's one where the fan doesn't operate in neutral...please understand that if you know I have one of those because of the listed model I am not trying to disagree with your statement, I just want to be certain that's what this model has vs. that is what it is doing and is simply in need of repair.

2) Lastly, Hennings website says the Super-Chuffer II works for TMCC engines.  Does it matter that the #4006 6-11149 is a Legacy engine?

Also, in case it matters I measured the resistance of the heating element after the engine had not been used for almost 14 hours.  My understanding according to a few other posts by gunrunnerjohn, this engine came with a 6ohm resistor and Lionel advised using an 8ohm.

Thank you for your time and consideration,

Steve

@Steve W posted:

@Vernon Barry the Super-Chuffer II (designed by @gunrunnerjohn) came to mind but I have two questions.

1) Is noted above in detail, briefly restated here:  Is there a way to know if this Legacy engine should be running the fan in neutral or if it does indeed stop in neutral? No, this model NEVER had idle smoke fan control by design. This is all based on the control boards that lionel built in that time. I cannot be much clearer on this. During the time of the semi-smart unit idle smoke was not a feature. Even different models of the smoke units- none of them had idle smoke- it just did not exist yet as a feature.

2) Lastly, Hennings website says the Super-Chuffer II works for TMCC engines.  Does it matter that the #4006 6-11149 is a Legacy engine? No, it controls the fan so it does not care one bit- legacy or tmmcc, or conventional. It is simply a smart fan control in a standalone module you are adding to your engine. All it does is sense the chuff switch status and if the smoke resistor is getting power. From those 2 simple inputs it decides is smoke unit on and heating, then it enables fan function of chuffing or idle smoke.

With super chuffer II, you unplug the fan from the current board. You then wire the fan motor to the super chuffer board. You wire power- pickup and ground to the super chuffer board. Last, you wire in 2 more signals- power sensing them smoke resistor input and the chuff switch to ground (both would also be input wires to the original smoke unit PCB) That's it. It's basically about 5 wires.

Also, in case it matters I measured the resistance of the heating element after the engine had not been used for almost 14 hours.  My understanding according to a few other posts by gunrunnerjohn, this engine came with a 6ohm resistor and Lionel advised using an 8ohm. Correct, and a 10 Ohm reading is not less than 8 and within a margin of error of expected.

Thank you for your time and consideration,

Steve

I have a special version of the Super-Chuffer that I can supply on request that is compatible with Legacy operation.  The Legacy chuff is triggered on the opening of the chuff switch, the TMCC chuff is triggered on the closing of the chuff switch.  That being the case, the sense of the signal has to be reversed in the Super-Chuffer to synchronize the smoke chuff with the sound.  Other than that issue, the installation instructions of the Super-Chuffer are the same as for TMCC installations.

Thank you for the helpful information @gunrunnerjohn.

Although no one has stated it, I gather everyone's understanding is the fan on this engine does not run in neutral.  Once am back working I will move forward with requesting the special version.

Thank you again

A lot of the locomotives of that vintage didn't have fan in neutral.  I put my special version of the Super-Chuffer into my C&O 10-wheeler.  AAMOF, it's the one that I discovered that the Legacy chuff triggered on the opposite edge and thus made a special version for Legacy.

The 10-wheeler had a lame fan control board that did chuffs while moving, but nothing when stopped.  For the size of the board, they should have been able to do the whole job!

Conveniently, it was at least as big as the Super-Chuffer.  I slipped the Super-Chuffer into the same place as the old board, right behind the smoke unit, a perfect fit.

Job done, smoke in neutral and better chuffing to boot.  While I was at it, I also gave the locomotive the LED Rule-17 headlight feature since it was free.  I could have also used the automatic cab light, but this particular locomotive already had that feature from the factory.

@gunrunnerjohn, I am impressed.

I, and I know many others, have benefited from so many of your responses to questions, never mind the things you have designed for the hobby.

Thank you for all that you do for the hobby and those on the forum.