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30 Hearing and touch.--A great deal concerning the proper running of an engine can be told by the sounds heard in the engine room. The vari- ous sounds tend to combine into a sort of rhythm, and the experienced ear can tell when matters are going well and when even very slight deviations, from this ordinary rhythm are pres- ent, and:this forms a very efficient means of detecting and locating faults. The chief sound is the rather' dull and heavy thump caused by the pounding of the main or crank-pin bearings. This can be located by ob- serving which crank has just passed the center when the thump is heard, 'remembering that the thump will be heard after and not before passing the center, or by filling bearing with oil the thump will be lessened. If the bearing is felt and found to be warm, or the thump felt by other means, the knock is located. The main bear- ing will have a duller sound than the crank pin or crosshead and will be felt all over the structure. The cross- head knock is a sharper sound and is not heard at so great a distance. Often lost motion can be told by feeling the bearings. Placing' a piece of metal against one part and the other end against the teeth or ear will also give indications. A valve being loose on its stem or 'piston loose on rod causes a solid, "sharp: thump or a. dull click: On starting up or 'slowing down, slide yalves are apt to rattle or cause a clicking sound due to lack of pressure on their backs. Attached air pumps, on becoming flooded, give a heavy thump. due to excess of water; or this may be caused by the absence of an air cushion, which may be remedied by- opening air cock on bonnet for a moment. Spring rings vibrate mote at cer- tain speeds and cause a rasping sound at times. Other sounds inside - the cylinder are caused by moisture in the steam and by the rings and cylinder walls becoming dry. When this rasp- ing sound is heard while engines are in free route, a little cylinder oil put on piston rod or some graphite and water introduced into cylinder will re- lieve the noise. Scraping and grunt- "ing, caused by water in the piston ° rings, is generally only heard on start- ing up and slowing down. The spring rings of piston valves give a sort of whistling sound when dry. The cylinder relief valves are apt to rattle when there is little pressure on them. Stuffing boxes sometimes squeal, due to insufficient lubrication. The churning sound noticed about engines is due to the passing of steam cleaned out, TAE Marine REVIEW through ports. There is a difference in sound showing whether the port opening is ample or not. This differ- ence may be noticed by running cut- ° off well in and out and observing the change. Touch is of great use in feeling the degree of heat and to determine slight movements not otherwise noted. The sense of smell is of great value in detecting heating or improper lub- rication, as the smell of heated and burning oil can be noticed. Taste come' into use in tasting feed water to see whether it is fresh or brackish. - HEATING. Various moving parts are liable to heat. This is caused by (1) improper or insufficient lubrication, (2) bear- ings becoming out of line, (3) bearing set up too tight, (4) grit or dirt from inferior oil or from engine room get- ting into bearing, (5) uneven surface of bearing or brass. Bearings and special regard had for lubrication. Hi there is a sort of lather on the bearing, it is a sign of proper lubrica- tion. Good oil running out shows that there is too much oil. Heating or the smell of burning oil shows a lack of lubrication. If bearings get warm, the supply of oil should: be examined and increased. Ii it oeis. warmer, water may - be sprayed on or circulated through, ac-. cording to which arrangement is sup- plied. But water should be avoided, if possible, the danger being that all parts are not cooled at the same time, and there is danger of bending, warp- ing, or cracking, due to sudden and unequal contraction caused by the cooling effect of the water. Tt. the temperature-of a bearme continues to after having in- creased the oil supply and we have a hot bearing, other means must be rise -taken. The danger of a hot bearing is that the brasses may expand till they grip the journal, thus causing a constant increase in the friction and heat. With increased heat the white metal may run. Slowing down will reduce the friction. Slacking back on cap bolts will 'increase the' clearance and _ pre- vent gripping; but these cannot be slacked back too much, as pounding will result. By stopping and readjusting the heated bearing, the matter may be remedied. This is probably -the best way, as it is the surest. If the bear- ine is not: large, it- can be taken off, covered with graphite, and a liner inserted in a few minutes, and on starting off it will be alright. Water must be frequently felt It is thus a very good practice to have paper and thin copper liners, al- ready cut, at hand for all. bearings, so that there is no delay in fitting them. For cooling a bearing, tallow, black lead, and sulphur are advisable as they absorb heat. ; Water should not,. except in most extreme cases, be sprayed on a hot bearing and should only be used be- fore very great heat is manifested. A great objection to the use .of water is that, being lighter than oil, it gravi- tates to the lower part of the bearing | and thus displaces the oil, and. after water is once started in a bearing, it is..difficult to get it properly oiled. may .be constantly used on 'guides and thrust bearings which are arranged hollow so that the water does not come on the sliding surfaces. Often on trial trips streams. of water are run continually on all the principal bearings, but in those cases the water is started before the heating begins. This is, however, not good practice for ordinary running. Heating due to bearings being out of line or. poor' surfaces cannot be effectively remedied except by read- justment of -parts, the only remedy in these cases being to run slow and to use oil freely. OILING. Oiling in connection with the opera- tion of engines consists in (1) keeping the oil boxes or cups supplied with oil, (2) supplementing this supply by hand where necessary, (3) oiling by hand small bearings that do not have separate pipes, (4) lubricating piston and valve rods, (5) internal lubrica- tion, (6) regulate water service. ~The oil boxes are usually filled from a reservoir tank located in top of en- gine room with pipes leading to: all the various boxes so that they can be filled. Where no such system is pro- vided, the boxes are filled by using an oil measure. Ojling by hand is done with the squirt can; a small half-pint can is usually the handiest. In addi- tion to the squirt can the oil syringe is used to reach parts that are out of the way, such as slides, piston rods, etc. For the fast-moving engines, syringes are generally used in place of .the squirt can. Piston rods and valve rods are lubricated by means of swabs, using cylinder oil mixed with graphite, also by oil syringes. On large bearings tallow cups are provided, and. these have to be filled by hand. The covers. of all oil boxes and cups should be kept closed to pre- vent dirt from getting into oil. There no definite rules to 'be given regarding the frequency of lubri- are