Voltage regulator

The exact product number is useful here.  Is this the Vision Line Challenger, the standard Legacy Challenger, or the Legacy Lionmaster Challenger?

The smoke element and fan are controlled separately in all of these products, but different boards are used, depending on the specific model.

You Say Challenger and then SD70ACe, obviously these are two totally different locomotives.  What are you having problems with?

Possibly an S gauge locomotive?

Good point, but it would still be useful to know the product number and if it's a Challenger or an SD70ACe.

That's the problem with "vanity" signatures. They become confusing to the person reading the body of the message.

I'm so sorry I was just putting the sd70 cuz I had one haha sorry. The challenger is the 6-48084 legacy  s gauge. New ssmu board, new resister was a 8ohm and I wired it down to a 5.9 ohm Lionel is saying that they did away with the 6 and went to the 8. But I loved the 6 it filled my room with smoke in seconds. It stopped smoking when I hooked up a different power unit. I'm a disabled vet who has been blown up many times while in Iraq so if I forget to mention something please forgive me. Or better yet just don't post anything. I'm an HO person really. Just had some money so I bought a couple s gauge trains. Love this steam engine. Would really like to get it smoking again. I use a 100watt 60 cycle transformer AC power. Is this enough info. Again thanks. 

The six ohm resistor was a mistake, that's probably where the problem started.  The regulator is specifically designed for the 8 ohm load, the six ohm load is asking too much of it.  The reason that Lionel originally went to the 8 ohm resistor was the excessive failure rate of the AC regulator modules.

Let's assume the regulator voltage was designed to dissipate 5 watts in the 8 ohm resistor.  That would be 6.3 volts RMS at .8 amps.  If you put a 5.9 ohm resistor in, the power goes to 6.8 watts and the current 1.07, that may be too much for the regulator circuit and it's overheated and killed something.

Ok I'll give you a little more info. All this happened originally on the six ohm factory stuff. I hasn't done anything yet with anything new I put in. So something else got fried??  I'm thinking I should just send it back to Lionel and let them fix there mistakes??  

Oh and the old board when it happened looked like fried chicken. The lines going from the pins the element were lifted right off the board. Pretty much fried the board. The old resister is like totally crispy and this happened while full of fluid. So it was never run dry. And still burnt up that bad. 

Here's the parts page for this locomotive: Lionel 6-48084 UP Challenger Parts.  As you can see, it uses the standard AC regulator module.  I'd seriously consider taking it to a qualified tech for repair.

The fact that the PCB has been cooked leads me to believe that the resistor may have shorted to the smoke unit fluid chamber, you have to make SURE it doesn't touch the sides of the bowl.

If you are bent on repairing it yourself, you probably need at least these two parts, and I'd also replace the smoke resistor with the 8 ohm one.

Here are the old and new parts.