Hi all, Recently my the smoke unit in a K-line hudson has begun pouring out smoke when the engine is idle rather than just during the puffs like it use too. Does anyone have any idea what the problem is thats causing this?
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Is this a command or conventional locomotive? If it's command (TMCC), can you turn the smoke off with the remote? If that doesn't work, the triac may be shorted.
I have a K Line Suburban and when the engine idles the fan runs to prevent the unit from overheating. When it's running the fan will make momentary stops giving the puffing effect.
Hi John. I'm running command and am able to shut off the smoke.
That removes the obvious. Did it ever not generate smoke when it was idle on the track?
That happened to my K-Line smoke unit just before it crapped out.
Originally Posted by gunrunnerjohn:
That removes the obvious. Did it ever not generate smoke when it was idle on the track?
It never generated smoke until now. Another strange thing is that even when running the smoke doesnt seem to puff up as high as it use too.
Originally Posted by Jumijo:
That happened to my K-Line smoke unit just before it crapped out.
Hopefully that's not whats going to happen here! Might have to order a new unit if thats the case.
I'm not familiar with exactly how that K-Line smoke unit is controlled, it sounds like it may have a regulator similar to the Legacy stuff that is dying/dead.
This is confusing, your title is a mechanical smoke unit, but we are talking about it as if it is a fan driven unit?
If this is modeled after the Lionel unit, it is possible the FET on the smoke unit that controls the fan has shorted and the fan is now running all the time instead of just during chuff. Can you show a picture of the smoke unit? G
It does sounds like a fan driven smoke unit from the description of the issue. If this is a mechanical unit, smoke pouring out at a stop would certainly indicate to me that it's going to have a very short life!
Hi,
Sorry about the confusion, I've just never seen this happen before. The smoke unit is indeed a mechanical plunger unit.
Smoke "pouring" out of a puffer when it's not running is a bad sign! I've personally never seen that happen, I have to believe the smoke resistor is failing and you're getting way more heat than intended.
Time to open it up and see what's happening. The smoke resistor is easy to change and not expensive, but if it gets hot enough long enough it may damage other parts.
The resistor looks fine but it might be better just to replace it and see if that helps. Thank you for all of the recommendations everybody.
Something is odd if it suddenly started pouring out smoke for no reason.
Possibly the smoke triac is shorted and allowing full track power to the element.
Bill
Originally Posted by Boxcar Bill:
Possibly the smoke triac is shorted and allowing full track power to the element.
Bill
I mentioned that Bill, but he says he has command control of the smoke output.
Originally Posted by gunrunnerjohn:
Something is odd if it suddenly started pouring out smoke for no reason.
As I stated earlier, that's what mine did right before it died. The loco slowed way down when it happened, and the whole engine was hot. It now sits in my office as a display.
I believe you! 
The fact that he can still control the smoke unit with the TMCC is a bit odd, otherwise I'd believe what Bill said.
I guess I don't really see a problem there. A little smoke will come out when you stop, the smoke element is still heating. It doesn't appear you're getting excessive smoke, which is what I thought was happening from the description.
It's working the same as mine do. If the track power is on and the engine is not running you will still see smoke coming up thru the stack and remember it will get hotter than when the engine is moving so cut the track power down so you don't burn it out. Bottom line is it's not broken.
I just dragged out a Mikado with the puffer and let it sit idle with the smoke on. It generates a small amount of smoke sitting there, and then puffs about like yours when it pulls out. It's also a TMCC unit.
Hi thanks for the replies all. I couldnt help but worry because this was something I had never noticed it before. I ran my K-line B-6 which shares the same smoke unit and upon close inspection it appears to do the same thing. The effect isn't as bad with the smoke unit in, so at least it helped a little!
Take Care
Pretty sure that is quite normal. When my engine with the mechanical smoke unit is sitting at idle, there is voltage on the smoke resistor from the TMCC board, so it's normal that it would produce some smoke. I'm guessing it's probably not a great idea to leave the engine idle for long periods of time with the smoke on, that will probably burn the wick more than moving air through the unit.
