How to Test Engines to Ascertain Their Condition for Highest Efficiency According to Their Respective Ratings

The subject assigned to me on how to test steam fire engines to ascertain their condition for highest efficiency according to their respective ratings, is, I think, one of the most important features of modern fire-fighting. We are continually using every precaution to prevent fires through thorough inspection and by warning the public of the dangers of carelessness and neglect, and in spite of all precaution taken large fires occasionally occur. My experience has taught me that to be successful in conquering fires is to be in readiness for all conditions, and I wish to impress upon your minds that not only testing fire engines but all other apparatus used in fire-fighting is the key to success. Very often we become neglectful about our steamers because at the last fire they gave us satisfactory service and at the same time some mechanical trouble was just about to develop and would mean delay or probable failure to do its work, but with regular tests and thorough inspection these minor troubles may be avoided. For an example, I want to cite to you an instance which happened very recently in my department. We were starting our regular test of our extra first size engine, after connecting to the hydrant with the suction hose, when the pressure blew off the 2 1/2-inch hydrant end of the suction hose, which, of course, prevented us from making the test, until the necessary repairs had been made, which took about 3 hours. Had we been responding at a fire alarm where the services of a steamer were needed it would have meant a delay. Investigation has shown that where regular and systematic tests are made it not only shows up the weakness of the engines, but also increases the efficiency of the crews making them, by familiarizing them with the operating of the steamer, for in only a few departments do they receive sufficient training in operating engines to capacity. The brakedown of an engine at a fire or the inability of the crew to operate it to capacity may be the direct cause of confusion and the needless loss of property and perhaps life, and also of discredit to the department. In starting the test of a steamer I would take the time required to raise steam, thereby becoming familiar with the best amount of fire to be used, also the kind of coal to be used in order to obtain the quickest results. Simple tests of raising steam and throwing water through one or more lines of hose often bring out defects such as improper timing of steam valves, worn out pump valves or bad valve springs, loose or tight bearings, or the bad condition of the boiler, but the correct way of testing a steam fire engine is to have on hand the following apparatus necessary for a test: a revolution counter, a stop watch, a small pitot tube, two ressure gauges, the necessary nozzles and a ydrant cap. When the engine is running the maximum number of revolutions the gauge placed in the stream at the nozzle indicates the number of gallons flowing and the pressure as well. It is always convenient to obtain a book with the different tables shown, so that you may be able to know what the proper results should be There are many different tests such as the displacement test, high pressure test, valve test and suction test, but the one we are most interested in and which would cover all others is the test for the quantity of water and the proper pressure. In testing a steamer of the first size, run the engine at the rate of 300 revolutions per minute, pumping through S fifty-foot lines of 2 1/2-inch hose, with 1 7/8-inch nozzles, and the delivery should be 900 gallons per minute, judgment however should be used as to the condition of the hose, as old hose may cause a greater frictional loss. After finishing the pumping test, should the steamer not show the proper displacement test, a thorough examination of the steam end may reveal some adjustments of the steam valve, also an inspection of the pump valve may be the means of overcoming some trouble. I will say in conclusion that the importance of getting to a fire must not be overlooked, so that therefore it is very important to inspect the running gear of the steamer also.

* Paper read at Convention of Oklahoma State Firemen’s Association, Sapulpa, Okla., May 25-28, 1915.

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