Steam 101: What does a steam loco THROTTLE look like, and how does it work?

When teaching people how to run a steam locomotive I have had to explain the balance point on a throttle and how it can spring open or closed. Depending on the amount of opening it is possible to go either way. Always check your quadrant spring at the beginning of a shift. The balance point is the most efficient throttle opening but must be used when near track speed and then overall speed controlled by cutoff. Taming the WILD in the iron horse is a constant endeavor. As to those who are wondering how to tame a runaway, centering the reverser and opening the cylinder cocks usually works with a little help from the brakes.

no no no. you cant just leave it at "runaway train, ask me how i know" we need to know.

4:30 Air compressor's gotta get it's "Air time"

I've heard two tales this week about engines that ran away from leaky throttles. Never realized that was a common occurrence lol. Should show the folks how fun sealing up one of those domes can be 😏

I fit inside the dome 346! The throttle was out though. That peak down to the tubes gave a flashback of claustrophobia when I was working on 346’s dry pipe. I was ok most of the time but got a little stuck a couple times and had to do some deep breathing to calm down and work my way out.

Wow the amount of engineering that went into making these beasts work is incredible, and I love learning more about it! Thanks!

I've never been able to squeeze by the throttle on any of the locomotives, it was always a pipe dream to squeeze by.

a fun look into the bitz that make the Choo-choo go Chug chug. Hyce! no make the Choo-choo leave with nobody at the throttle.

Awesome!! Never knew what they looked like! Thank you!!

Keith Rucker has an amazing posting on how the throttle valves are repaired and lapped. Hyce. He does a lot of work on Locomotives in the Georgia area. Very nice guy. You should connect with him. Nice presentation - well done

Thank you, Hyce, for these detailed explanations of how steam locomotives work. Your videos are both instructive and entertaining!

491 just cosplaying as a babbling brook is great.

It is a balanced poppet valve. They were also used in the Cincinnati Triple Steam water plant.

So, how do you know? I'd love to hear that story. Also, thank you for posting such amazing content. This stuff fills a hole in my life that I didn't know I had.

"You can have a runaway locomotive, ask me how I know" Well since you asked. How do you know?

Thank you! Please, continue providing very in depth knowledge about steam locomotives!

After playing with both dome throttles and multiple front end throttles I much prefer a front end throttle, as long as it's set up right.

Very nice! I've seen some pics on Facebook of the Frisco 1630s throttle valve, and its very similar (thought obviously bigger, ya know standard gauge Decapod things) IIRC. Also happened to notice Smokebox is working on a UP 0-6-0 (S-6 Class specifically I believe) for TS:C, so that should be fun...

Neat, really demystifies the enigma steam power once was to me.

Thx for showing this to us! It blows my mind, how komplex steam locomotives are!