Large Scale Central

New and old Climax smoke unit

Can someone tell me what the voltage and polarity of the wiring to the climax smoke units is? I have and old climax and a new one. Don’t like the high voltage smoke units and want to replace them with the Sleuthe 5v units and a regulator. I already bought the regulators and the smoke units are coming. I need to know if the wiring is constant polarity or if it changes with the locos direction. If it does I will need to install a bridge rectifier so I thought I’d ask as I’m sure someone already knows the answer. I know I can figure it out with my meter but just trying to save myself some time. Thanks in advance.

I would not use a 5 volt regulator as the LGB seuthe smoke units are really 4-7 volt units and most LGB engines give the smoke units and lights at least 6 volts, some as high as 6.8.

I use the LM7806 regulator and have had no issues with the ‘5 volt’ lgb units or lights. And if I want more volts I add a diode to the regulator ground leg and get 6.7 volts.

What Sleuthe unit are you using?

I have one and was thinking of doing the same thing.


Hello gentlemen,

the regulators I have came from ebay and are adjustable so thanks for the voltages Dan. I’ll just turn up the pots. I had ordered 4, 5v sleuthe smoke units from trainworld with their last sale but they notified me that they’re sold out so I ordered some units from Trainli. Yesterday I pulled two smoke units from both my old climax and my shay, then soldered in my regulators with rectifiers and adjusted the pots to 5.2 volts. Once my smoke units come in, I’ll wire them to the regulators and turn them up to the 6 or so volts you recommend. I’ll post some pictures. I have three engines in total to change over but originally ordered two so I have a couple more coming.

on another note: I actually found a problem I had with my shay that I didn’t know about. When I wired up the regulator and to test, I put an led on the output side, I got no light when powering up the front truck. The truck ran but no power at the new regulator. I then realized that the rear truck wasn’t running. So I then powered the rear truck and the led came on along with the cab and headlight. Turns out one wire that feeds power off the upper truck contact had broken. Soldered the wire back and all is well. I now realize why the shay wasn’t running that great last time I ran it. I thought it was dirty track and just a lack of running it much recently.

Hi Ted. I have no idea if the regulators you bought are the same as the ones I got. They were dirt cheap, about $12 for a box of 5. They work well with one exception. I use them as a voltage source for a “dim” setting on some low voltage LED ceiling down lights. Every once in a while, while on “dim” my lights will flash briefly to “bright” which is the input voltage to the regulator. It’s a very short spike and does not bother my LEDs as they can handle the input voltage, but sensitive electronics may not be so happy. YMMV

This is what I bought. 2 for $10.99, free shipping.

Not the same one, so never mind :slight_smile:

I’m away in Florida right now but when I get home I’m going to get back on this project. Every vendor I tried was out of 5v smoke units and had no idea when they were getting more. I was able to find one vendor who stocks them in bulk with no retail packaging Or small bottle of smoke fluid. They were priced very right and I even got two that are 3-4 volt which should still work with the regulators I bought. All are Suethe units and all got delivered to my house today. I bought around 10 smoke units in total as he gave me great price. I have a ton of moguls also so hopefully I won’t need to ever buy more smoke units. Just picked up and older climax in excellent condition but with Phoenix sound for half the cost of the sound alone. Looks like I have another candidate for a regulator/5v smoke unit conversion. More to come.

Wired in the regulator boards into my climax and shay locos. I used the 4volt suethe units with the regulator set at 5 volts. All three locos now smoke extremely well and look much better moving on the layout. I used a 11/32” milling bit to slightly open the bottom of the strai stack on on climax so the smoke unit would go down flush with the top of the stack. On my older climax I used the original wiring as it is off the switch. On the shay and new version climax I wired the smoke unit off of the front truck power leads using the original switch in my shay and using a small spare switch from my RC plane hobby I the new cli. I left the original switch still wired in but shrunk a piece of tubing around it to prevent any shorts. It all tucked in the front of the boiler without any problems.

I also added a Phoenix climax sound system to my new climax so I have great sound and great smoke on my analog DC track powered climax. I also went with the flat screen topped stack supplied with the climax asan alternat. I made up a brass extension to raise the suethe unit inside the stack to a good height and keep it stable. I had a PH hobbies steam sound system that I added to my shay. I put two magnets on the drive shaft and get a decent sound on my shay along with great smoke. While not shay prototypical, the sound is still reallygood to hear over a silent running loco. I had to order a 3” speaker as the PH one supplied was too large.