How to Boot A Steam Locomotive

For my fellow live steam fans, a wonderful article on how to bring an oil fired locomotive up to temperature and get it moving.

About a 6 hour affair for this engine. As far as you can get from the push-button starting of turbines and piston ICE powered trains.


The maintenance schedule for the Willys, with all the “every few hundred miles” intervals, reminds me of a comment I heard somewhere about new vs old cars:

“They don’t make them like they used to. Thank God.”

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Way cool article, thanks for sharing that! Well written, quite enjoyable.

Ahhh low pressure steam. At least it’s an oil locomotive and not a coal one … then you’re gonna be shovelling as well.

And then there’s high pressure marine steam turbines… here’s a good read on those.

Seems a coal locomotive is easier to get going (at least in theory) - shovel in coal, light coal, wait for water to heat up.

All the checking and oiling would be the same but non need to raise steam to start the fire.

There’s less bits to be heated. No concerns about heating fuel lines until the oil can flow. The process is still likely to take 4-6 hours though. Metal that thick, pipes that long and dissimilar materials besides. If those systems heat up too fast stuff starts to pull itself apart; sometimes with spectacular results if parts were under pressure when it happens.

It might light easier, but it’s so much more maintenance. Busting clinkers out of the firebox, opening up the boiler to play chimney-sweep on every fire tube. Messy.

Process of getting a coal fired locomotive going from cold. It doesn’t seem to be meaningfully different in terms of time/process. I don’t know of a writeup, sorry… try youtube-dl if you can’t tolerate the 50,000 ads.

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Can someone explain this sentence from the original article to me?

The fire is now a bright yellowish white, and I examine it through the peephole, adjusting the steam valve for the burner to try and fan the spray of fuel to provide an optimum bloom of flame that just about fills the firebox, but is not so energetic that the flame front gets ripped away from the burner, so that it keeps reigniting from sheer heat, a condition leads to a series of hollow sounding explosions and a great loss in efficiency.

The steam valve controls… Not the amount of fuel, not the amount of air, but the distribution/mixing of fuel. Is that right?

What does “reigniting from sheer heat” mean and is it desired or avoided? What sort of efficiency loss is in mind here?

There is this interesting bit of physics, but I’m guessing the fuel flows freely enough at this point that it isn’t the sheer/shear heat mentioned:
Shear Heating - Beaumont Technologies, Inc.

Already, the boiler pressure has reached 25 pounds. As I watch, I can see the needle rising. I grab a bucket of feedwater treatment (chemicals that reduce scaling and rust inside the boiler) and climb up over the tender and head to the hatch. The water level is now less than a foot from the top, and I dip the bucket and mix the chemicals with a loose piece of pipe. Pouring the mixture into the tank, I head back to the cab and check the water column. Forty pounds of steam, and the glass is now showing about a half an inch of water.

What water was the mix added to while the boiler gained 15 pounds of pressure? Surely something other than the pressurized boiler.

I’ll try, based on my admittedly limited understanding of all the details, but with probably more reading on steam engine tech than the average bear.

The steam valve, as I understand it, controls the injection of the fuel oil into the combustion chamber. Imagine a paint sprayer, bead blaster, or any other system where a stream of moving air creates a low pressure and brings other stuff along. Replace the air with steam (because you’ve got a ton of it and it helps heat the fuel at the final injection point), and you’ve got a system that will finely vaporize oil and spray it into the combustion chamber. I believe the fuel flow valve is separate, but the steam valve here will impact the pattern of the spray and how wide the spray pattern is, how far into the chamber it goes, etc.

Blowing the flame out with too much steam, and having a hot enough firebox that the now not-burning oil spray finds something hot and lights off again. You have, at that point, a firebox full of oil and air, not burning, and it starts burning all at once. It’s the same basic problem as a rocket hard start and RUD, just without (ideally) blowing the boiler up. I’m sure the efficiency of random kabooms is far lower than a steady, smooth burning of oil, before you consider the efficiency of disassembling a boiler full of steam.

The makeup water supply in the tender, which is unpressurized. Just dump it on in.

A neat post by Ray Dewley, from Railway Preservation News:

I have fired oil and might give some insight on doing so. First of all, RUN AWAY!!!.. Just kidding. I have fired wood and coal as well. Oil is physically easy, but mentally frustrating.

The basic theory of operation is that the burner is on constantly and the fire brick opposing the burner is the “ignition system” in that it glows red after a short time and reignites any “flame-outs” (I had one - the fire goes quiet and the stack goes white on #2 oil, then comes an earth shattering KABOOM when she relights). The way the oil is atomized is basically two different ways - internal or external mixing. Internal mixing (the one on the engine I work on)is where the oil is mixed with the steam and exits the burner as an aerosol. The external mixing type flows oil over a slit with the atomizing steam issuing from it. You are adjust a “spot fire” in the terminal for an “idle” fire position on the valve handle quadrant with a firing or drifting pin.

The location and orientation of the burner in the firebox or pan is usually under the tubes with the burner aimed at the brick in the firebox below the door opening. Baldwin had some of theirs in the pan pointing up at the same target. the small Baldwin I run occasionally had it level targeted under the door.

The fire is regulated along with demand and water supply to boiler, with a faster heat response than coal. Here’s something to remember you can build a really hot fire in a big hurry and damage the firebox if not careful.

When plumbing a burner, provide a pet cock for slow bleed for keeping any condensate out of the burner - you don’t want water in your fire or firebox

More here: Railway Preservation News • View topic - Oil Burner Control for Steam Locomotives - Re: YRE & 614

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