Front end throttle

[Anonymous]

Several of my steam railroad books mention the term "front end throttle." What does this mean, was there an auxillary throttle located on the front of the smoke box, or was the steam dome on the front end of the boiler? I've asked several railroad buffs at work, and we can't come up with an answer. thanks.

[ndbprr]

Obviously there has to be a way to regulate the steam and a valve is used. The farther back in the boiler the valve is the shorter the linkage on the throttle the engineer operates to regulate steam flow. A front end throttle has the valve at the fornt or smokestack end of the engine. I have no idea why this was done or what the advantage was. You will see the rod on the side pof the boiler going to a small linkage that works the throttle. The only possible reason I can think of is that it got the valve away from the firebox and into an area were it could be worked on without having to drop the fire completely.

[Anonymous]

Another advantage is that when the locomotive was under high steam usage conditions the front end throttle could deliver a bit more steam because the pressure drop caused by the throttle (even when completely open) was closer to the cylinders.