A. Forcing the fire is very hard on fire-box sheets and flues, and will cause them to leak. An even temperature should be maintained in the fire-box of any locomotive.
16. Q. Is a careful regulation of steam and oil valves and dampers necessary to obtain the most economical results?
A. Yes; the fireman's oil valve should be opened just wide enough to permit a sufficient amount of oil to be fed to produce a good fire, but not wide enough to waste oil or produce a volume of black smoke.
17. Q. How can you judge whether the combustion is good or bad, so the valve may be regulated accordingly?
A. By the color of the fire in the fire-box. When it is a dull red color, the temperature is below 1,000 degrees and combustion is incomplete, dense black smoke will issue from the stack. If it is a bright red, the temperature will be about 1,800 degrees and combustion very good, and no black smoke will appear from the stack.
18. Q. How should the flues be cleaned from soot when running, and about how often is this necessary?
A. By placing a small quantity of sand in an elbow shaped funnel or horn, and by inserting same in an opening provided in fire door while engine is working hard, allowing the exhaust to draw the sand through the flues, thus cutting soot and gum from them in its passage and discharging it from the stack. It is necessary that the flues be cleaned of soot on leaving terminals or sidings where the engine has been at rest for any length of time, and also as often as found necessary to aid the engine in steaming. This depends to a great extent upon the degree of perfection with which combustion is obtained. Attention should also be given flues just prior to entering points where engine is to be put in roundhouse or otherwise detained in order to leave the flues clean, as this will aid in putting engine under steam with little delay where the blower alone is to be relied on for draft.
19. Q. Is the injudicious use of the blower particularly injurious on an oil burning locomotive?
A. Yes; the injudicious use of a blower is injurious to any boiler. The cold air drawn through the fire-box is hard on the sheets and flues and will cause them to leak.
20. Q. Is the blower more injurious when a light smoke is emitting from the stack or when a dense black smoke is emitting?