Lionel dynachuff issues on Mikado Jr

Well, that's not dynachuff, that's just triggered chuff. Knowing the difference is kind of important because they are not even in the same ballpark of troubleshooting.

Dynachuff- dynamic chuffing sound increase (more bass, louder)  based on throttle position and is and advanced serial data driven railsounds function

Plain old triggered chuff- the concept that there is a a switch or trigger system, tied to one of the axles to trigger chuffing with rotation of the wheel.

So we look at the parts breakdown of your engine and low and behold- there is a mechanical microswitch for the chuff trigger- and being mechanical- they can go out of adjustment and/or fail and become intermittent.

In this engine, there is a cam on the front axle set, that drives this little "push rod/smoke lever" part 32 and that then triggers the microswitch mechanically.

https://www.lionelsupport.com/...LOCO-ONLY-6101100001

part #9 https://www.lionelsupport.com/...CH-DG23-B1LA-3A-125V

Wow, thanks for the detailed response! I will check this first. I was going by Lionel info.

Lionel just like the sound of DynaChuff.

I’m a bit apprehensive about disassembling this loco to find that switch. Unable to find detailed schematic. Any suggestions? Thanks

You should be able to see the switch by just removing the boiler shell.  If you're not able to do that, I'd suggest taking it to someone to repair.

Well, Vernon and John. In the end, had I known what I was dealing with it would’ve been a simple bending of the metal arm that contacts the switch spring. Both of your input was instrumental in getting it fixed and running properly. The hardest part is simply not having experience,removing the shell was completely easy as everything was accessible from the top. But I made the mistake of trying to adjust the spring on the switch(which was fully functioning and still good) and eventually broke the plastic housing that holds it in. I can honestly say I’ve put in a good 4 to 5 hours on this project , had I known what to do, it would’ve probably been 30 minutes tops. But that’s how life is, you just have to keep persisting and not give up! HAPPY days. I hope this post will be of help to someone who may experience the same issue Brian.

The first time is always the hardest.