Resistors for smoke unit

The 27 ohm resistor may have been defective. I would try that again for conventional.

For command running I would try a 30 ohm resistor. Lionel has them available. If it burns up again, I would suspect there is a problem in the electronics, as TMCC mode delivers approx. 1/2 track voltage to the resistor, when you push the boost smoke button, it gets full track voltage. The 27 ohm resistor is rated for 12-14 volts

@ADCX Rob posted:

The 27 ohm resistor may have been defective. I would try that again for conventional.

Thank you for the help as I am not running conventional. I am running 18 volt track power with Cab 1L &  Base 1L. Thank you for your help. Chuck had suggested a 30 ohm resistor for command running. so I will give that a try. Thanks Again

@Chuck Sartor posted:

For command running I would try a 30 ohm resistor. Lionel has them available. If it burns up again, I would suspect there is a problem in the electronics, as TMCC mode delivers approx. 1/2 track voltage to the resistor, when you push the boost smoke button, it gets full track voltage. The 27 ohm resistor is rated for 12-14 volts

Thanks Chuck, I will certainly order a few up & give it a try. I'm am curious if 30 ohms is that much different from 27ohm.  Is the 30 ohm made to handle the 18volts track voltage?  Somewhat new to this area. Thanks for your help.

The Lionel standard for years in TMCC equipment has been 27 ohms.

We've kicked this around before.  Slightly more sophisticated, some of the smoke units, also, have a thermistor, that inhibits resistor burn out. (That little blue thing) 

@ADCX Rob posted:

The 27 ohm resistor may have been defective. I would try that again for conventional.

@DCS213 posted:

Thank you for the help as I am not running conventional. I am running 18 volt track power with Cab 1L &  Base 1L. Thank you for your help. Chuck had suggested a 30 ohm resistor for command running. so I will give that a try. Thanks Again

If the 30 ohm isn't satisfactory, try the 27 ohm again, but get a good one...  just be aware that they all have a service life. They do not last 70+ years like the original Lionel nichrome wound elements.

@Mike CT posted:

We've kicked this around before.  Slightly more sophisticated, some of the smoke units, also, have a thermistor, that inhibits resistor burn out. (That little blue thing)

As it runs out, the thermistor doesn't do as much as you'd think, at least in Lionel Legacy smoke units.  It's there primarily to limit the initial boost power, not to continually monitor and control the heater.  TAS had one that did actually control the heat, but it was problematic enough that I normally bypassed it.

@gunrunnerjohn posted:

As it runs out, the thermistor doesn't do as much as you'd think, at least in Lionel Legacy smoke units.  It's there primarily to limit the initial boost power, not to continually monitor and control the heater.  TAS had one that did actually control the heat, but it was problematic enough that I normally bypassed it.

So do you have a solution to my problem, without costing a fortune. It is TMCC but old style of Legacy as I was told. When that 27ohm resistor burned up it stopped smoking. What would you suggest? I'm just looking for some smoke & not burn resistors out after 3 to 4 hours of use and that is not constant usage. Any help appreciated.

It this a mechanical smoke unit or a fan driven smoke unit?

The reason smoke resistors burn out on mechanical smoke units is when you stop the locomotive with power on the tracks there's no airflow.  That will eventually cook the resistor if you don't turn off the smoke.  There is no solution to that issue to be had by selecting smoke resistors.

@gunrunnerjohn posted:

It this a mechanical smoke unit or a fan driven smoke unit?

The reason smoke resistors burn out on mechanical smoke units is when you stop the locomotive with power on the tracks there's no airflow.  That will eventually cook the resistor if you don't turn off the smoke.  There is no solution to that issue to be had by selecting smoke resistors.

It is mechanical. Older TMCC K-Line. If the main board has an area to plug in a smoke unit, would I be better off purchasing a fan driven smoke unit. If so who is the best to buy from & cost if you have an idea. Thank you.

There's a lot more to adding a fan driven smoke unit than just buying one.  You'll have to at a minimum mount it, probably fabricate a stack extension, and then wire it in.  If you want it chuffing, that's a whole different kettle of fish!

I operate old Gilbert and newer American Models engines on command control, there are some work arounds us S gaugers use to do it. The S gauge mechanical piston smoke units that use nichrome wire are 34 ohms. These work ok with the command track voltage set at 13 to 14V. Need to keep them full of fluid. 15 drops every 10 minutes of operation. Do not let them sit unmoving on a powered track for more than 5 or so minutes. My layout has block power controls so I can selectively turn off track power.

The units with smoke resistors are usually 27 ohms. If it is a Gilbert style two chamber unit it helps a lot to drill out the diameter of the two holes the wick passes through. Keep the command voltage at or slightly below 14V. I run my American Models Pacifics with mechanical smoke units this way and so far in 9 years no smoke resistor has failed. They never sit for long on a powered track.

I had two American Models large Northerns converted to fan driven smoke and ERR TMCC/Railsounds. As Gunrunnerjohn states it is not a simple plug and play swap. The smoke units are MTH. The chuff signal is generated from two magnets on a tender axle. A fair amount of custom fab was done to correctly mount the smoke unit under the stack. The end result is worth it. There is a video of an American Flyer Northern with the same mods on www.goldinhands.com, fan driven smoke is the way to go.

@DCS213 posted:

Thank you for the help as I am not running conventional. I am running 18 volt track power with Cab 1L &  Base 1L. Thank you for your help. Chuck had suggested a 30 ohm resistor for command running. so I will give that a try. Thanks Again

The question that needs to be asked is, how is your Kline wired for smoke?….if someone altered the original wiring for conventional power, they might have wired your smoke unit straight to track power, …..if so, in command mode, ie; 18V on the track all the time, then yes, you’ll burn out a 27 ohm resistor in short order,……when running in TMCC, your smoke unit power should come from the radio board, and not straight from track power,…

Pat

I've converted dozens of locomotives from puffers or Seuthe smoke units to fan driven smoke.  I did enough of them that a finally came up with a couple of products to make the job easier, the Chuff-Generator and the Super-Chuffer II.

You mentioned K-line. Is this the resistor that is mounted to a green circuit board on the smoke unit? If so they are notorious for burning up. Got a pic?

@gunrunnerjohn posted:

There's a lot more to adding a fan driven smoke unit than just buying one.  You'll have to at a minimum mount it, probably fabricate a stack extension, and then wire it in.  If you want it chuffing, that's a whole different kettle of fish!

Sounds like I bit off more than I can chew. Sounds like I may have to put a 27 ohm resistor in & just run it Conventional or sell it & apply the $$$ towards a Legacy. Really do like the style of this train. Oh well seem's like conventional is my best option. Thank You.

@harmonyards posted:

The question that needs to be asked is, how is your Kline wired for smoke?….if someone altered the original wiring for conventional power, they might have wired your smoke unit straight to track power, …..if so, in command mode, ie; 18V on the track all the time, then yes, you’ll burn out a 27 ohm resistor in short order,……when running in TMCC, your smoke unit power should come from the radio board, and not straight from track power,…

Pat

Great information, I may have to have somebody look at this, as is it is getting to be more than I can handle. Not knowing if someone ever changed how it was wired. With not being able to get schematics to know how it should be wired & values.