Publisher's Synopsis
This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1906 edition. Excerpt: ...the cap nut 98. Clean both the valve and its seat thoroughly, being careful not to scrape the face or seat of the valve with any hard material. 27. Occasionally the excess-pressure valve becomes stuck shut so that air cannot get into the train pipe past it when the brake-valve handle is placed in running position. This results usually from the use of too much and too poor oil in the air end of the pump; the oil forms a gum that gradually blocks the excess-pressure valve, and may cause trouble in other parts of the air-brake system. With the excess-pressure valve stuck, the engineer very often goes over the road with the brake-valve handle in full release, and with no excess pressure. If the excess-pressure valve sticks, take it out and clean it. The best time to clean the excesspressure valve is just before starting the pump. This can be done in a few minutes and will cause less annoyance than if it were allowed to remain stuck and the valve carried in full release during the entire trip. If the excess-pressure valve 97 works stiffly in the cap nut 98, the valve will be less sensitive than usual and the excess pressure will fluctuate. That is, when the valve works stiffly, more than 20 pounds excess pressure must be obtained before it will open, while on the other hand, it will not close until the excess pressure is less than 20 pounds. 28. A leak at the main slide valve or past the excesspressure valve that will allow train-pipe and main-reservoir pressures to equalize will maintain them equal, and since, with this brake valve, the governor is set to stop the pump as soon as full train-pipe pressure is obtained, the pump will not start again until the pressure in both train pipe and main reservoir is reduced to that amount. If this reduction is...