Oil fired locomotives

[Anonymous]

Dear everyone,
I'm not an expert, but I have read a short book on oil burners and volunteer on an oil burner, so I'll share what I know for certain:

1.) The floor of the firebox on an oil buner is solid, there is no gap between the sides and bottom (in practice, small gaps of sunlight can be seen, but it's not a big deal.
2.) As best I know, Bunker C = No. 5, but I've also heard No. 6 was used. Really, anything flamable and liquid can be used, as long as it doesn't burn so hot as to cause problems. For example, because of logistical problems, we usually burn diesel fuel instead of fuel oil (it's harder to fire, but works okay). Gasoline, on the other hand, burns too hot.
3.) Before heating, No. 5 is like jello in consitency. In cold whether it can be one step removed from asphalt.
4.) It is made more fluid by heating it with steam put into the tender (it condenses, and at the end of the day the tank is drained of water). The oil then is gravity fed to the burner at the front of the firebox. On the way, it passes through a larger pipe filled with steam, which increases its fluidity. This is called the oil heater or "superheater" (not to be confused with the superheater in the boiler for steam). "Oil heater" is the more common term by far. Locomotives generally had one burner at the front of the firebox, but a few (NOT necesarily larger) ones had two burners, one at the front and one at the rear. Having the burner at the front works best for drafting purposes.
5.) The oil is made into a fine mist by being sprayed with steam in an arcing fan-shape from the burner (also called the atomizer)
6.) The control of air is accomplished with the damper, which can either be at the front of the firebox (the "throat sheet) on horizontally drafted fireboxes, or up from the floor on vertically drafted fireboxes.
7.) The SP extensively used Von Boden-Ingalls burners, while the AT&SF extensively used Booth burners. There were, as always, certainly exceptions.

I hope this helps a little.

Sincerely,
Daniel Parks

[markpierce]

Fuel oil was sprayed into the firebox, with the oil being consumed before it could puddle. Bunker C fuel oil was used after gasoline production became important, I think around the late 1920s. Engine fuel oil was lighter before then (lighter than water), but when the petroleum companies changed their production mix to make more gasoline, the railroads had to use a thicker grade (like Bunker C). The oil fuel (both lighter and heavier) had to be heated so it would flow properly, about 100 degrees f. See my Oct. 25 comment in the "Southern Pacific Camelbacks?" topic, discussing the higher energy content of oil over coal.

[Anonymous]

So, what other locomotives used this bunker C fuel? Is it just these oil steamers and UP turbines or some other locomotives used it too?

[Anonymous]

That's what I heard.

[Big_Boy_4005]

Didn't UP convert both 844 and 3985 to oil burning? Too many grass fires, and easier to fill with oil instead of coal.

[Anonymous]

No they look like a regualr steam loco. So is that why in old pictures you can see the fire glowing under teh engine, is that an indication it is a oil burner? If it isn't open on the bottom of a coal burner, how do you get enough draft to burn, it can't all come throught the cab, or can it?

[Anonymous]

Anyone have any pictures of these oil locomotives? Or are these turbine locomotives you are talking about?

[TomDiehl]

The earliest ones burned an oil known as Bunker C, a thick, almost tar-like substance that had to be heated with steam so it would flow. Later ones, like the SP GS-4's used a #5 fuel oil (most home heating is #2 or 3, higher numbers being thicker). They were burned much like the home heating oil burners, with a series of jets. which were simply placed in the firebox where the grates would have been for a coal burner. I believe the bottom, where the ash pan is on a coal burner, was open to allow for drafting the fire.

[Big_Boy_4005]

What an interesting question James, well done. I am far from knowledgible on this, but I would have to think it would be something like heating a home with oil. In that situation water is also boiled. Oil certainly has advantages over coal, easier to start, and no cinders.

[Anonymous]

So with a oil fired locmotive. How thick is the fuel when it burns? Does it vaporize, then burn? When more fuel is added what keeps it from just puddleing up on the floor of the firebox? How is the oil added to the fire box, wouldn't just spraying it over the fire smother it slightly? Is it run through some kind of burner system on the floor?