Steam & Excursion > Observations of a "Big Boy" overnighting.

If I observed correctly, a locomotive like "Big Boy" can be left guarded overnight near 300 psi, fire put out, 2 stacks capped, 2 firebox air intakes covered, the cab door and windows closed, and main steam fountain closed. Pressure might then drop to near 100 psi.
Next morning, the cab, stacks, air intakes, and fountain are opened. If oil is still warm, fire is lit. Pressure rises to near 300 in near 2 hours. Add water to boiler as needed. With brakes applied, gear full forward, and cocks open, throttle a slight pressure to clean out cylinder water. Repeat with gear full reversed. Return gear to center. Work condensate from whistle if any. Start dynamo for lights. Please correct me if errors.

You pretty much covered it all. And as we would start out movement in the morning we would have the cylinder cocks open to work the condensate out of the cylinders as the built up water works its way down into them. Overnight all the remaining steam internally cools to water and is forced out of the system as the fresh steam emits from the boiler to the cylinders. Once the locomotive "Dries out" they are closed and all the steam is now working in the cylinders to create the massive horsepower and tractive effort.

Bob Krieger
Cheyenne, WY

A 200psi drop overnight seems really excessive.  1522 had a 210 operating pressure.  We would do all of the above when shutting her down at night and would always have at least 160psi the next morning.  One time in Galesburg, she went two days without a fire and had enough steam to heat the oil and light off.   Her boiler was tight!

Spikes Wrote:
-------------------------------------------------------
> If I observed correctly, a locomotive like "Big
> Boy" can be left guarded overnight near 300 psi,
> fire put out, 2 stacks capped, 2 firebox air
> intakes covered, the cab door and windows closed,
> and main steam fountain closed. Pressure might
> then drop to near 100 psi.
> Next morning, the cab, stacks, air intakes, and
> fountain are opened. If oil is still warm, fire is
> lit. Pressure rises to near 300 in near 2 hours.
> Add water to boiler as needed. With brakes
> applied, gear full forward, and cocks open,
> throttle a slight pressure to clean out cylinder
> water. Repeat with gear full reversed. Return gear
> to center. Work condensate from whistle if any.
> Start dynamo for lights. Please correct me if
> errors.

I notice that you make no mention of blowing out at least a half glass of dirty boiler water, using both the right and left main blowdown cocks. Prior to doing ANYTHING, the first thing in the morning after the locomotive has sat all night, is to open the big blowdown cocks, located at the lowest forward corner of the firebox, one on each side. Such process removes most of the mud and other solids that have been fed into the boiler during the previous day's operation. Not performing these VERY IMPORTANT blowndowns every morning, will eventually lead to a boiler belly full of mud/concrete, just like what happened to 844 in about 2013 (remember those photos posted on TO?).