LGB 21985 Poor Smoke Output

R

R. Wolfe

Registered
25 Jun 2017
44
1
53
Pennsylvania
I was working on a 21985 which I purchased new with a poor smoking problem. A very weak stream of smoke was being produced. Even with the smoke stack plug removed, very little smoke. This locomotive comes factory with MFX sound decoder and 5-volt Seuthe unit. Marklin had sent me another 5-volt smoke unit to try. It was not any better so I decided to do some testing. The first thing I did was check the voltage to the unit. It was getting 5.1 volts under load. The older LGB locos I tested put out anywhere from 5.5 volts to 7 volts under load. I thought I could raise the voltage slightly via the decoder cv settings but soon learned that it was all ready set to a max setting of 255. This means that the smoke voltage is regulated via the main loco circuit board and not by the decoder. The only thing the decoder does for the smoke function is act as an on/off switch. I was able to find a Seuthe 4E smoke unit which is rated 3-4.5 volts. I tested it under load and it starts smoking lightly right at about 3.4 volts. At 4.5 volts, it smokes very well. I was a little concerned about overheating the unit and possibly causing damage to the locomotive so I bench tested it at 5.7 volts for 10 minutes. It smoked just as good at 4.5 volts as it did at 5.7 volts. I kept an eye on it the whole time and could see no glow(glow is bad) from the element and you could hold the smoke unit in your bare hand as it was only slightly warm to the touch. Keep in mind I only am going to be putting 5.1-5.2 volts to the unit. I installed it in the locomotive and it works great. I also have an LGB 20752 with MFX and a similar problem. I suspect I will probably find the same issue with it as well. It was a real bummer to spend $700 on a LGB locomotive and it smoke so poor. Problem solved.... Richard
 

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idlemarvel

idlemarvel

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13 Jul 2015
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Ascot
Thanks Richard, I'll be doing the same with mine.
 
stevedenver

stevedenver

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24 Oct 2009
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Thanks
I have some older decoder ready locos that similarly smoke feably. Green spremberger, ballenburg rack.
I have long suspected some issue in a change in wiring, but you have clarified things.

I think ill track down a couple of the lower voltage seuthes and try them
 
R

R. Wolfe

Registered
25 Jun 2017
44
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Pennsylvania
I have two Piko Moguls and they both Smoke extremely well at slow speeds. I ordered a replacement Piko Smoke unit (to keep as a spare) which is made by Seuthe and if I remember correctly, the wires were different color from the LGB 5-volt Seuthe units. The 5-volt ( model# 5E) have Black & White wires. The 4E has Brown and White wires. I will have to check (buried somewhere in my parts boxes) but I think the Piko unit may of had the same Brown & White wires.
 
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R. Wolfe

Registered
25 Jun 2017
44
1
53
Pennsylvania
Okay I was able to confirm Piko is using a 4E Seuthe unit. The wires are the same brown & white color. Piko advertises it as a 5=volt unit part # 36142. see the link. 36142 Smoke Unit 5V (G-Scale)
 
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Dan

Registered
28 Jan 2010
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8
Eastern MA
I was under the impression that the LGB smoke unit was a 4-7 volt unit and always smoked better when over 6 volts.