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LOCOMOTIVE BBEAKDOWNS

EMERGENCIES AND THEIR REMEDIES

An up-to-date catechism treating on accidents and break- downs on the road and how to repair them. Every kind of an accident which is likely to occur to a locomotive, including engines of the most modern type, is fully considered and the remedy given in plain language, and, in most cases, clearly illustrated. The Wal- schaert valve gear is included with special ref- erence to each individual piece of the mechanism, as is also the locomotive elec- tric head light, and a full course of instruc- tions on air-brake defects, troubles and errors in up-to-date operation, are given. The several styles of compound locomotives are included.

Contains over 400 Questions with their Answers

By GEO. L. FOWLER

Revised and enlarged by WM. W. WOOD,

Air-brake Inspector

FIFTH EDITION, REVISED AND ENLARGED

NEW YORK

The Norman W. Henley Publishing Co.

132 Nassau Street 1908

Copyrighted 1908

by The Norman W. Henley Publishing Co.

Copyrighted 1903

by

The Norman W. Henley Publishing Co.

Composition. Printing ami Elect retyping by

PUBLISHKRS PRINTING Co.

New York

OF THE

UNIVERSE

s£U.JF<

PREFACE JO FIFTH REVISED AND ENLARGED EDITION.

This collection of remedies for emergency locomotive work is not original and newly devised by the author, or it would not be applicable to presently existing conditions and circumstances. The value of technical-instruction books is in the fact that they represent the results of practical application and tests of theories, and in compiling this work the only originality involved has been in con- nection with the revision of the present edition; authorities differ as to the best methods of dealing with certain troubles, and this book presents the latest ideas on those subjects, embodying the methods pursued by practical enginemen, and indorsed and recom- mended by the Travelling Engineers and Master Mechanics. Emer- gency measures that a few years ago were universally advised in cases of breakdown are found to be impractical with the extremely heavy engines of the present day, and in this revision the author has sacrificed some of the really preferable methods that were for years unquestioned as the proper remedies in cases of road troubles and still required by some authorities, to the present-day principle of the least road repair compatible with safety, in order that an acci- dent may not develop into an engine failure as determined by time delayed, and that the engine can get a paying load under way as soon as possible.

As this book is intended for the benefit of every one in any way connected with the locomotive, the chapter on Engine Repairs is the premium to the Shop and Roundhouse men, illustrating a num- ber of handy devices used in locomotive shop repairs, and, while

1 Cl/fW-1 o

PREFACE.

not coming within the limit of road emergencies, may be considered valuable when time is an important element that demands instant recourse to the quickest means of effecting what practically amounts to emergency repairs.

With the expansion of the Air-Brake chapter, and the added features of the Walschaerts Valve Gear and the Electric Headlight, the author and the publishers are exceedingly satisfied with this revised edition, and believe that it is exactly what locomotive enginemen need and want; they all know what to do when the engine is all right, and this book will enable them to know what to do when the engine is all wrong — and we don't believe that very much of importance has escaped the present edition.

WM. W. WOOD, Air-Brake Inspector. March, 1908.

TABLE OF CONTENTS.

CHAPTER PAGE

PREFACE Introduction.

I. Defective Valves 15

II. Accidents to the Valve Motion, Stephenson Link Gear. . 34

III. Accidents to Cylinders, Steam Chests, and Pistons .... 57

IV. Accidents to Guides, Crossheads, and Rods " 68

V. Accidents to the Valve Motion, Walschaerts Radial

Gear 79

VI. Accidents to Running Gears 88

VII. Truck and Frame Accidents 108

VIII. Boiler Troubles 1 18

IX. Defective Throttle and Steam Connections . 136

X. Defective Draft Appliances 139

XI. Injector Troubles 144

XII. Accidents to Cab Fixtures 157

XIII. Tender Accidents 165

XIV. Miscellaneous Accidents 168

•

XV. Accidents to Compound Locomotives 186

XVI. Tools and Appliances for Making Engine Repairs... 215

XVII. Locating and Remedying Air-Brake Troubles 229

XVIII. The Pyle-National Electric Headlight 252

LIST OF ILLUSTRATIONS.

PAGE

Fig. i. Valve Stem Clamp 18

Fig. 2. Method of Blocking Crosshead with Four-Bar Guides 20

Fig. 3. Method of Blocking a Laird Crosshead 21

F"ig. 4. Method of Lashing Blocking for Alligator Cross- head 21

Fig. 5. Blocking Ports with Valve Removed 22

Fig. 6. Method of Blocking Valve with Broken Valve Stem.. 22

Fig. 7. Holding Board Over Stuffing Box 23

Fig. 8. Repairs to a Broken Packing Box Gland 25

Fig. 9. Closing Stuffing Box when the Gland is Broken 26

Fig. 10. The Tilting Action of the Yoke on the Valve 29

Fig. ii. Blocking Piston Valve in Central Position with Wood

at Each End 31

Fig. 12. Method of Blocking Piston Valve with Steam Pres- sure 3-

Fig. 13. Stuffing Box Packed with Hemp on Top of Broken

Ring 34

Fig. 14. Rocker Arm Tied to Frame to Clear Link 37

Fig. 15. Link Blocked and Held by Wood Over Link Block.. 38 Fig. 16. Link Blocked at Top and Bottom for Broken Lifting

Shaft 40

Fig. 17. Blocking for Broken Lower End of Reverse Lever or

Broken Reverse Lever Fulcrum 42

Fig. 18. Blocking for Broken Reverse Lever 42

Fig. 19. Lashing Lifting Arm to Beam Laid Across Frame... 43

Fig. 20. Clamping Two Eccentric Rods Together 45

Fig. 21. Location of Eccentrics Relatively to the Crank 46

Fig. 22. Side Elevation of Link Motion 50

Fig. 23. Application of Tram to Valve Stem 52

Fig. 24. Measuring Position of Link Block Relatively to Axle. 53

Fig. 25. Tramming Driving Wheel to Locate the Dead Center 54

Fig. 26. Hydrostatic Piston-Rod Remover 57

Fig. 27. Method of Blocking Port for Broken Cylinder Head. 58 Fig. 28. Method cf Blocking Steam Passages with Broken

Steam Chest . 63

LIST OF ILLUSTRATIONS.

PAGE

Fig, 29. Clamping Board Over Port with Steam Chest 64

Fig. 30. Blocking of Piston with Board Inside of Cylinder.... 68

Fig. 31. Method of Blocking for Broken Driving Axle 80

Fig. 32. Chaining Underhang Equalizer When Main Driving

Axle is Broken 80

Fig. 33. Holding Up Rear End of Engine With Rails Chained to Frame and Tender for Broken Rear Driving Axle or Wheel... 80

Fig. 34. Blocking up Axle with Broken Driving \Vheels 82

Fig. 35. Blocking Beneath Spring Stirrup to Relieve Broken

Driving Box Brass 85

Fig. 36. Striking Piece for Equalizer with a Cracked Spring

Plate 90

Fig. 37. Method of Blocking Frame with Broken Main Driv- ing Spring or Hanger 90

Fig. 38. Blocking for Broken Driving Spring of Ten- Wheeled

Engines 94

Fig. 39. Method of Chaining Four- Wheeled Truck Frame with

a Broken Front Axle 95

Fig. 40. Method of Chaining Truck Equalizer on Mogul and Consolidation Locomotives with Broken Truck or Truck Axle 96

Fig. 41. Method of Chaining Truck Equalizer on Mogul or Consolidation Locomotives with Broken Truck or Truck Axle 99

Fig. 42. Outline of Method of Blocking Four-Wheeled Truck

with Broken Frame 100

Fig. 43. Method of Chaining Four-Wheeled Truck with

Broken Spring Hanger 101

Fig. 44. Method of Blocking Engine Truck Frame with Broken

Spring 103

Fig. 45. Method of Blocking a Mogul or Consolidation Loco- motive with a Broken Equalizer 105

Fig. 46. Method of Blocking a Mogul or Consolidation Loco- motive with a Broken Cross Equalizer 105

Fig. 47. An Alternative Method of Blocking a Mogul or Con- solidation Locomotive with a Broken Cross Equalizer 106

Fig. 48. Pole Sharpened for Plugging Tube and Ready for

Insertion m

LIST OF ILLUSTRATIONS.

PAGE

Fig. 49. A Plugged Tube 1 1 1

Fig. 50. The Morgan Tube Stopper 112

Fig. 51. Lap Seam 116

Fig. 52. A Welt Seam 1 16

Fig. 53. A Bagged Crownsheet 121

Fig. 54. Plate Bolted Over Tee Head for Broken Steam Pipe. 128

Fig. 55. The Master Mechanic's Front End 131

Fig. 56. Boarding Used to Replace Broken Front Casting.... 132

Fig. 57. Section of Locomotive Boiler Pump 143

Fig. 58. The Nathan Cylinder Lubricator 146

Fig. 59. The Gollmar Bell Ringer 150

Fig. 60. Spliced Tender Hose 153

Fig. 61, Chained up Tender Truck 154

Fig. 62. Common Wrecking Frog 160

Fig. 63. Wrecking Wedges for Re-Railing Wheels 160

Fig. 64. The Alexander Wrecking Frog 161

Fig. 65. The Cooke Wrecking Frog -. . . 162

Fig. 66. Section of Intercepting Valve of the Richmond Two- Cylinder Compound Locomotive 175

Fig. 67. Section of By-Pass Valve of Richmond Compound

Locomotive in Open and Closed Position 180

Fig. 68. Plugged By- Pass Valve of Richmond Compound Loco- motive 182

Fig. 69. Intercepting Valve of the Schenectady Compound

Locomotive when Working as a Simple Engine 186

Fig. 70. Intercepting Valve of the Schenectady Compound Locomotive in Position for Working as a Com- pound 188

Fig. 71. Longitudinal Section of Valve of Vauclain Compound

Locomotive 199

Fig. 72. Bracket for Supporting Side or Main Rods 204

Fig. 73. Lever for Holding Side and Main Rods 204

Fig. 74. Tongs for Removing Oil Box Cellars ; 204

Fig. 75. Device for Lighting Headlights 205

Fig. 76. Hydraulic Bolt Starter 206

Fig. 77- Cannon Bolt Starter 207

Fig. 78. Air Ram for Removing Bolts 208

Fig. 79. Common Knots and Hitches 209

Fig. 80. Diagram of Frame Weld 213

Fig. 81. Method of Strengthening a Cracked Bridge 214

LIST OF ILLUSTRATIONS.

PAGE

•Fig. 82. Banded Crank 215

Fig. 83. Strengthening Crank, with Dove-tailed Insert 215

ILLUSTRATIONS ADDED TO THE FIFTH REVISED AND ENLARGED EDITION.

Pacific-Type Passenger Locomotive Frontispiece.

Fig. 30 (A). Mallet Articulated Compound Freight Locomotive

with Walschaerts Valve Gear 80

Fig. 30 (B). Detail Parts of Walschaerts Valve Gear 82

Figs. 30 (C), and 30 (D). Examples of the Most Common Method of Application of the Walschaerts Valve Gear ; Showing the Difference in Eccentric Location and Upper Connections of the Combination Lever as between Engines with Valves of Inside Admis- sion and Outside Admission 85

Fig. 56 (A). The Simplex Locomotive Injector 150

Fig. 85. Nine-and-Qne-Half-Inch Air Pump 230

Fig. 85a. Nine-and-One-Half-Inch Air Pump 231

Fig. 86. Pump Governor 234

Fig. 87. Engineer's Brake Valve 239

Fig. 88. Diagrammatic Arrangement of the "ET" Engine and

Tender-Brake Equipment 246

Fig. 89-89 (a). The Two Most Commonly Used Locations for the Engine and Dynamo of the Locomotive Electric

Headlight 251

Fig. 90. Folder. Sectional Elevation of the Pyle-National Electric Headlight, Engine and Dynamo, With

Lists of Detail Parts

Fig. 91. Method of Smoothing the Commutator — Electric

Headlight 258

Fig. 92. Rear View of Lamp and Reflector — Electric Head- light 259

LOCOMOTIVE BREAKDOWNS, EMERGENCIES, AND THEIR REMEDIES.

INTRODUCTION.

Q. What are the first duties of the engineer in case of, the breakdown upon the road?

A. The first thing to be done after stopping, is to see to it that the train is protected by flagmen in both directions in case of a single track road, and in the rear on a double track. If the nature of the accident is such that both tracks of a double track road are in any way obstructed, flagmen should be sent to the front as well as the rear. Should the breakdown be one that is likely to require much time to put the engine in running order, word should be sent to the nearest telegraph station, flagging a passing train to send the message if necessary.

The next thing to do is to determine the character of the mishap and locate the damage ; ascertaining whether it will be necessary to ask for outside assistance, and, if it will be, sending to the nearest telegraph station for the same at once. Finally, work should be started immediately to put the engine in condition to move. There is almost always something that can be done before outside help arrives that will facilitate the preparations and shorten the time during which the disabled engine will be blocking the tracks.

TI

12 LOCOMOTIVE BREAKDOWNS.

Q. Name a few of the principal troubles that are to be looked for on a locomotive.

A. The troubles experienced in every day service on loco- motives are those ordinarily due to wear and tear and to bad water and coal. These may cause the valves and pistons to leak and blow ; the moving parts of the machinery to pound while in motion; the draft to become insufficient to maintain the fire at the proper intensity to generate a suffi- cient quantity of steam; the injectors to fail to work, and the boiler to prime or foam.

Q. Are any of the troubles named above dangerous to the operation of the locomotive?

A. That will depend upon the degree to which the defect has been allowed to advance. In the case of a blowing valve or piston there is usually little danger in running, provided that it is due to simple wear and not to a broken part. Where the pounding is light there may be no immediate danger ; but this defect will continually increase and, whew it is allowed to become excessive, a breakdown may be the result. Where the water is of such a character as to cause the boiler to foam or prime there is danger that water may be carried over to the cylinders and cause a breakage there. A poor draft may merely mean a delayed train. It should always be- remembered, however, that any defect, no mat- ter how slight, may be the direct cause of greater ones, which may result in a breakdown or disaster.

Q. What are the duties of the engineer in regard to these classes of defects?

A. He should observe them closely and, in case they

INTRODUCTION. I3

appear to indicate a dangerous condition of affairs, he should stop at once and apply the proper remedy. Should there be no apparent danger of an immediate breakdown he should proceed to the terminal and report the defect to the roundhouse foreman for repairs.

Q, What. preparation should be made in order to be able to deal with emergencies and accidents rapidly and without hesitation?

A. In the first place the engineer should familiarize himself with all of the details of locomotive construction and especially of that class which he is called upon to. run. It will be found that each will possess some peculiarity of construction that will make it necessary to modify the in- structions given in the following pages to a greater or less extent. This will be especially true of those calling for blocking and chaining where the parts are closely crowded together. It will be well, then, as a preparation for what may happen, to go over the particular engine in detail and see what can and must be done in the case of a breakdown of any individual part. This will be a particularly valuable preparation in the matter of fastening and chaining in con- nection with the springs, driving boxes and related parts. In short, it should be borne in mind that it is the man who has worked out the problem in advance that is the one who is ready to deal with an emergency.

CHAPTER I. Valve Defects.

Q. How is a blow in a valve detected?

A. The principal difference between the blowing of a valve and a piston in the cylinder is that that of the valve is apt to be the more steady of the two. There is also a difference in the sound which it is impossible to describe and which can only be learned by actual experience on an engine. The only suggestion that can be made is that a valve blow is apt to have a suggestion of a whistle in it, while that of the piston partakes more of the nature of a roar. This sound can be heard more distinctly if the furnace door is open than if it is closed.

Q. Is an intermittent blow a sure indication that it is not caused by a valve?

A. No. A valve sometimes leaks intermittently, produc- ing a corresponding blow. That is to say, it may not leak at all points of its travel, or it may become tilted at some one point, thus allowing the steam to blow through. This latter usually occurs at the end of the travel, but rarely or never happens at all with the balanced valves.

Q. Is a whistling in the exhaust a certain indication of a leaky valve f

A. No. If the exhaust nozzles or passages become clogged or gummed with oil from the cylinder, they fre- quently produce a whistling in the exhaust that closely resembles the sound caused b a leak valve.

1 6 LOCOMOTIVE BREAKDOWNS.

Q. Having determined that it is a valve that is causing the blow, how can it be located?

A. As the valve blow is apt to be continuous no indica- tion of its location can be obtained by watching the effect of crank positions on the sound. The test can best be ap- plied when the engine is at rest. Adjust the valve motion so that the rocker arm is vertical and the valve is in its mid position and then, by admitting a little steam, the blow can be heard quite distinctly. A method of determination while the engine is in motion, is to go out upon the running board while it is moving slowly and yet working hard and place the foot upon the valve rod. The side upon which the blow takes place is apt to tremble and show signs of an extra stress. This, however, may also be due to the hard run- ning of the valve on account of insufficient lubrication. Still another means is to place the engine on the quarters successively, open the throttle a very little and move the reverse lever to and fro. The leak will be upon that side having the crank pins on the quarter when the reverse lever moves with the greater difficulty.

Finally the same principle may be applied while the en- gine is in motion, by unlatching the reverse levers and hold- ing it by hand when moving slowly and noticing the location of the cranks when a distinct jerk takes place. The blow will usually be found to be on the side whose cranks were on the quarters when this occurs.

Q. What is apt to be the first indication of a leaky valve?

A. If the leak is due to a broken strip, the blow may announce itself suddenly and with full force. If it is due to

VALVE DEFECTS. 17

wear of the valve face or seat it is apt to come on gradually, increasing from day to day with the abrasion of the two parts in contact.

Q. What is the characteristic feature of a blow resulting from a leaking piston?

A. It is apt to come on suddenly and is intermittent.

Q. How can a piston blow be located?

A. Place the engine with the cranks on the quarter suc- cessively and with the reverse lever in the forward notch start the throttle slightly ; taking care to have the cylinder cocks open. If steam appears at both cocks of the piston whose crank is on the quarter, the leak is on that side. Where the steam appears at one cock only the piston is tight.

Q. If, in making this test, steam does appear at both cylinder cocks is it a positive evidence of a leaky piston?

A. No. It may be due to a broken bridge between the ports of the cylinder casting, which would allow steam to pass through from the steam chest or ports to both ends of the cylinder at once.

Q. How can it be ascertained whether the blow is due to this cause or not?

A. By testing the matter with the reverse lever in both forward and back positions. If steam appears at but one cylinder cock with the lever in one position and at both cocks when in the other it is a sign that a broken bridge will be found to be the cause of a blow.

Q. In case a violent and steady blow is suddenly devel- oped to what can it probably be attributed?

A. To a breakage of a valve, or a portion of the cylinder

i8

LOCOMOTIVE BREAKDOWNS.

casting within the steam chest, or to some of the valve connections, such as yoke, stem or packing strips.

Q. What should be done under these circumstances?

A. Stop at once and ascertain the exact cause, by remov- ing the steam chest cover.

Q. In case it is found that a bridge has been broken ivhat should be done?

A. If the valve has not been injured, the broken pieces

FIG. i. — VALVE STRM CLAMP.

of the bridge should be removed and the valve clamped in the central position with a valve stem clamp similar to that shown in Fig. i. It consists of the two parts A A, with V notches for setting down over the valve stem and bolts for tightening it so that it will hold. Each is also provided with

VALVE DEFECTS. 19

an extension and slotted hole for setting over the gland studs, the nuts of which will hold it in the proper position. The method of application is to first adjust the valve, then slip the clamps into position and up against the face of the gland. Then tighten the clamping bolts, after which the gland nuts can he run home, thus firmly fixing the valve in the position in which it is placed.

Before fixing the valve the valve rod should be discon- nected from the rocker arm and separated from the valve stem. As this disables the engine on one side the other working parts should be disconnected also.

O. How is an engine to be disconnected in case of a disabled valve?

A. The valve rod should be disconnected from the rocker arm as already stated in the answer to the previous question. If the valve rod cannot be readily removed, it should be sprung slightly to one side to prevent the rocker arm from striking it. It will not be necessary to disconnect the link or eccentric rods.

The connecting rod should be taken down, and the cross- head pushed to the extreme limit of its stroke and then blocked in position. As a general statement, it may be said that it makes no difference at which end of the stroke the crosshead is blocked, but on some consolidation, mogul and ten-wheeled engines the crankpin of the forward driving wheel will not clear the crosshead with the latter blocked at the back end of its stroke. It is well, therefore, to always block the crosshead and piston at the extreme front end of the stroke.

2O

LOCOMOTIVE BREAKDOWNS.

Q. How is the crosshead to be blocked when discon- necting?

A. In case of a crosshead working in four-bar guides, the blocking is done as shown in Fig. 2. The crosshead is pushed with the piston to the extreme forward end of the stroke and a block of wood, A, is inserted between the guides completely filling the space between the back end of the crosshead and the guide block. The block is itself held in

FIG. 2. — METHOD OF BLOCKING CROSSHEAD WITH FOUR-BAR

GUIDES.

place by lashing or wrought iron straps B bolted to either side of the block A by a single through bolt.

For crossheads of the Laird type, the block may be fitted against the bottom of the guide and held in position by lashing or by straps and bolts as shown in Fig. 3.

For crossheads of the alligator type working between two guides, the same method of fastening can be used as in Fig. 3. Should the straps and bolts not be available for holding the block, it can be lashed in place as shown in Fig. 4.

Q. What should be done in case a valve is broken?

A. In case the valve is still in such a condition that it

VALVE DEFECTS.

21

can be used to cover both the steam ports, set.it in the cen- tral position and clamp it there by means of the valve stem clamp (see Fig. i) and then disconnect one side (see page

FIG. 3. — METHOD OF BLOCKING A LAIRD CROSSHEAD.

19) and block the crosshead (see Figs. 2, 3, and 4). The engine can then be run with the other side.

In case the valve is so badly damaged that it cannot be used, as indicated, the ports may be blocked by fitting strips into them or a board may be laid over the whole valve seat as in Fig. 5 and be held down by blocking against which

FIG. 4. — METHOD OP LASHING BLOCKING FOR ALLIGATOR CROSSHEAD.

the steam chest cover is made to bear, thus holding the whole in position. It is particularly important that this board have a bearing all round the inlet passage or port at A

22

LOCOMOTIVE BREAKDOWNS.

so as to prevent the admission of steam to the steam chest. The valve is, of course, to be removed and the engine discon- nected as before.

Q. What should be done in case of a broken valve stem or yoke?

A. The engine must be disconnected and the crosshead blocked (see pages 19 and 20).

If the valve stem is broken outside the steam chest the

FIG. 5. — BLOCKING PORTS WITH VALVE REMOVED.

FIG. 6. — METHOD OF BLOCKING VALVE WITH BROKEN VALVE STEM.

valve should be put in the central position and clamped by means of the valve stem clamp (see page 18).

If the stem is broken inside the steam chest, it will be necessary to block the valve. This is done by fitting blocks of wood as shown in Fig. 6 in at the front and back of the

VALVE DEFECTS. 23

valve, between it and the steam chest, thus holding it in the central position. If it is an unbalanced valve it can be held down by blocking bearing against the steam chest cover. A balanced valve will need no such blocking.

In case of a valve stem or yoke thus broken within the steam chest, the removal of the same will leave an opening through the stuffing box. This must be closed and it can be done by means of a thin piece of board held against the out-

m «•

FIG. 7. — HOLDING BOARD OVER STUFFING Box.

side of the opening with the gland studs and nuts, as shown in Fig. 7.

Q. Plow can a broken valve stem or yoke be detected and located?

A. The engine should be placed upon the quarter and the cylinder cocks opened. Then admit a little steam to the steam chest and move the reverse lever backwards and for- wards. If steam does not escape alternately from the two

24 LOCOMOTIVE BREAKDOWNS.

cocks the stem or yoke will probably be found to be broken. In case one side is all right, put the other crank on the quarter and repeat the test.

Q. How can a broken packing strip of a valve be de- tected?

A. When a packing blows, a great deal if not all of the balance will be lost. This causes the valve to work hard. The best method of locating or detecting it is to lay out on the running board and grasp the valve stem in the hand. It will be found that the one with the broken packing strips will be working with very much greater resistance than the one in proper condition, and can be readily detected by the feeling. This work cannot very well be done when the engine is at rest, although it is possible to do it by setting the engine on the quarters successively, admitting a little steam to the steam chest and having an assistant move the reverse lever to and fro while the inspector holds a hand on the valve stem.

The trouble that may be experienced with this method is that the loss of balance for the valve may cause it to move with such difficulty that the reverse lever cannot be operated. (See also page 26.)

Q. If a valve stem or piston rod gland is broken what should be done?

A. If the gland breaks in two so that it is parted through the body, it is usually possible to repair it by wrapping the part outside the stuffing box with wire and then using a piece of board to push it into position with a steady press- ure as shown in Fig. 8. In case a lug only is broken off, the

VALVE DEFECTS. 25

piece of board put into position, as illustrated, will serve to bring the gland home. It must, of course, be cut open on one side as shown at A, in order to set over the stem or piston rod without necessitating the removal of the same from its position.

Another method that may be used, especially upon the left side where the escaping steam will not be a serious in- convenience to the engineer, is to remove a portion of the packing so as to allow the gland to enter its full length into

FIG. 8. — REPAIRS TO A BROKEN PACKING Box GLAND.

the stuffing box, and to hold it there by screwing down tight with one stud. This, of course, can only be done when at least one lug and stud are left in good condition and the body of the gland is uninjured.

In case both studs are broken and the gland fractured beyond the possibility of repairing, the stuffing box can still be kept tight. Cut a piece of board like that shown at A in Fig. 8, and after packing the stuffing box full of waste or packing, hold this board over the opening by means of a brace or braces as shown in Fig. 9. These may be two

26

LOCOMOTIVE BREAKDOWNS.

pieces of plank or one with the notch cut out to span the piston rod, and guides if necessary, and held in place by a piece of bell-cord running to a brace laid across the front cylinder head or front end of the steam chest, and tightened with a tourniquet, or a twist in the doubled cord. This last method is rather clumsy in appearance but can be made to

FIG. 9. — CLOSING STUFFING Box WHEN THE GLAND is BROKEN.

answer, besides being readily applied, since it should not take more than fifteen minutes to do the work.

Q. What is a dry valve and hovv can it be located?

A. A dry valve is one that has not received the proper amount of lubrication.

It can be located in exactly the same manner as a broken packing strip. In addition to this it will be found that, when the engine is in motion, there will be a decided jerk to the reverse lever when the crank, upon the side where the dryness exists, passes the top or bottom quarter. By

VALVE DEFECTS. 27

noting the point at which this jerk takes place the side can be located.

Q. What is a cocked valve and how is it remedied?

A. A cocked valve is caused by the valve lifting from its seat and becoming so cramped in the yoke that it cannot return to its proper position. It is usually caused by the yoke being made too tight. It generally takes place after steam has been shut off and at the time of making a stop.

When starting again the trouble manifests itself by a roaring and blow such as would be occasioned by a broken bridge, and may easily be mistaken for such a defect. The remedy to be applied is to jerk the reverse lever. This pro- duces a jar at the yoke which will usually loosen the valve and allow it to drop back into position.

Q. Hoiv can the general location of valve motion defects be determined?

A. By opening the cylinder cocks and watching the escape of steam while the engine is in motion. It should be noted that, when the engine is running forward, steam should escape from the forward cylinder cock during the backward stroke of the piston and out of the back cylinder cock dur- ing the forward stroke of the piston. Any variation from this indicates that there is something wrong and also the side where the trouble will be found.

Q. When the valves and the valve motion are in good condition what should be the character of the exhaust?

A. It should take place at uniform intervals of time and each blast should be of equal intensity.

Q. What does a variation from this condition indicate

28 LOCOMOTIVE BREAKDOWNS.

and does it rtcessarily indicate a serious condition of affairs?

A. It indicates that there is some defect either in the valve motion or the related parts, but does not necessarily mean that the engine needs immediate attention or that there is any serious loss in the efficiency of its operation.

Q. What are some of the causes that may produce this inequality in the intensity or the timing of the exhaust?

A. They may be almost any defect related to the valve motion. The most common cause is one that is irremediable except by a reconstruction of the valve motion and is due to inherent defects of design. The link motion forms a very delicate combination that must be adjusted with the utmost accuracy or the defect will manifest itself in the "square- ness" of the exhaust. Other accidental phenomena are bent main driving axles, slipped eccentrics, loose eccentric straps, bent eccentric rods, bent or loose rockers, bent valve stems, loose valves, inequality in the size of steam passages, unequal travel of the valve, clogged exhaust nozzles, holes, worn in the petticoat pipe and exhaust nozzles not in proper alignment with the stack.

Q. How can the general condition of the valves be tested?

A. The engine may be placed on the quarters and the wheels blocked. The reverse lever is then so adjusted that the rocker arm stands vertically. The cylinder cocks are open and a little steam is admitted to the steam chest. In this position no steam should escape from the cylinder cocks. If any does escape it indicates that there is a leak.

It sometimes happens that a valve will be tight in its cen-

VALVE DEFECTS.

29

tral position and leak at the end of the stroke. In making the above examination it is well to move the reverse lever so as to change the position of the valve, but still not enough to uncover the ports.

Q. How does wear ordinarily take place on valves and seats?

A. The average tendency is for the valve to wear convex and the seat concave. This may be due to a variety and

FIG. 10. — THE TILTING ACTION OF THE YOKE ON THE VALVE.

combination of causes. The lip of the valve projects be- yond the line of the yoke and the looseness of the latter has a tendency to tilt the valve as shown in Fig. 10. This throws an extra pressure upon the edges of the valve tending to wear it convex. The tendency to wear the seats con- cave is probably due, to a great extent, to the practice of working the engine upon the road with a reduced throw, thus giving more wear to the center of the seat than to the

30 LOCOMOTIVE BREAKDOWNS.

ends. This causes a slight concave wear and, when the valve is again thrown into full gear and its maximum travel, the ends travel up on the unworn portions of the valve seat, with an increased pressure per square inch of surface, and are worn away leaving a convex contour.

Q. When the valves and scats become so worn that they are leaky ivhat should be done?

A. The valves should be removed and planed to a smooth flat surface, and the valve seats be refaced. This latter can be done with a portable rotary planer which may be clamped into position on top of the cylinder when the steam chest has been removed. When, by repeatedly facing it, the valve seat has been worn away entirely a false one may be put in, and thus avoid the necessity of sacrificing the cylin- der casting.

Q. What is the cause of piston valves sticking and jerk- ing the reverse lever?

A. It may be due to the valves running dry as with the flat valve, or to an inequality of expansion between the valve and its case. If the valve is turned to a snug fit and is made light the admission of live steam to its surfaces will cause it to heat and expand more rapidly than will the heavier casting forming the steam chest. When this occurs the valve will be apt to catch and bind, a condition that may prevail when the engine is started quickly after a long period of rest.

Q. In case a piston valve becomes disabled, how should it be tested?.

A. The piston valve may be handled, in every way, in the

VALVE DEFECTS. 31

same manner as the flat valve. If it is to be blocked in the central position, the work may be done by clamping the valve stem as described in the answer on page 18. If it is to be blocked with wood on the inside, a piece fitted in at each end and bearing against the heads of the steam chest, as shown in Fig. n, will hold the valve in any desired position.

When this kind of blocking is to be done the best way is to remove both steam chest heads, set the valve in the cen- tral position, and fit in blocks that will just bear against the heads and the valve.

If, however, it is definitely known whether the valve has

FIG. ii. — BLOCKING PISTON VALVE IN CENTRAL POSITION WITH WOOD AT EACH END.

inside or outside admission a shorter plan may be followed. Push the valves against the front head and clamp 'it in that position. This will permit the cylinder to be filled with steam, which will hold the piston against one head. Discon- nect the main rod and push the piston to that end of the cylinder where the steam will tend to hold it and block it there (see page 20). This is shown in Fig. 12, where the mottled surface indicates the live steam.

This method must not be followed, however, unless a per-

32 LOCOMOTIVE BREAKDOWNS.

feet certainty exists as to the construction and action of the valve.

Q. Is there any tendency on the part of piston or Hat slide valves to move in the steam chest that makes it neces- sary to block them when the engine is disabled?

A. No. The steam pressure upon a flat valve merely tends to hold it firmly to its seat, while the piston valve is supposedly perfectly balanced and has no tendency to move. It is unsafe, however, to trust to this as the jarring due to the motion of the engine when running, may serve to move

FIG. 12. — METHOD OF BLOCKING PISTON VALVE WITH STEAM PRESSURE.

the valve, or the diameters of the piston valve may be such as to cause an inequality of pressure and a tendency to move. Under no circumstances, then, should an engine with a dis- abled valve be moved by its own steam without first block- ing the same.

Q. If, when an engine is disconnected and the valrc blocked in position, it is found that steam leaks into the cylin- der through the blocked valve, what should be done?

A. The cylinder cock at the end of the cylinder at which the piston is blocked should be removed. This permits the

VALVE DEFECTS. 33

steam to escape and does away with any tendency to move it away from that position. It will be better to leave the other cylinder cock in place, as steam in that end of the cylinder will assist in holding the piston in its blocked position.

Q. What unit be the effect and what should be done if the lip at one edge of the main valve is broken?

A. The effect will be the same as though the outside lap of the valve had been removed on that side. This causes a later cut-off for any given travel of the valve, besides giving a wider port opening. The result on a locomotive will be that, with the link in full-gear, the broken edge of the valve may travel so far as to uncover the exhaust port and thus permit the live steam of the chest to blow into the former and