Part 5

The engine is of the Side Crank, Side Gear style, the frame of which is the girder pattern with bored guides, and has an overhanging cylinder attached to one end, and contains the pillow block bearing at the other.

It is fitted with the Woolf Valve Gear for reversing, Friction Clutch, Cross-head Pump, Injector, Syphon for filling water tank on front end, and a large Foot Board with Tool Boxes attached. The wheels are of steel, and the traction or drive wheels are furnished with malleable mud cleats extending diagonally across the entire width of tire.

The boiler is safe with proper care, economical in fuel, and the engine moves over the road rapidly. Although simple in its general construction, it has all the appliances and fittings necessary on a traction engine.

TRACTION ENGINES.

=Traction Farm Engines= are becoming more generally used each year, and to supply the increasing demand for traction engines, the manufacturers have spared no expense or mechanical skill to place upon the market the latest improvements in this line, and a great many kinds of this class of engine now made in the United States are simply perfect. They travel over the roughest roads, up and down steep hills with heavy loads, and the engine is at all times entirely under the control of the engineer. In fact, there is no class of engines that has had a more marked advancement toward perfection in the past few years than the farm traction engine.

As this class of engines in the majority of cases goes into the hands of men inexperienced in the handling of machinery, they are subjected to the very hardest usage and neglect, which, of course, hastens their destruction. Every purchaser of an engine should acquire sufficient knowledge of the operating and handling of it so that he will know when it is properly cared for.

No engine has to run at more variable speeds than a traction engine. It is very important for this reason that the steam ports should be of sufficient area to admit of a very high piston speed, and allow the steam to follow the piston at the necessary velocity. Small ports are useless, as when the link is notched up, and the travel of the valve thereby reduced, the openings are too cramped for the steam to pass in and out of the cylinder comfortably. The result is, that the slide valve is forced off its seat and the engine primes as soon as any great speed is attained. It is easy to tell by the sound of the exhaust if the ports are rightly proportioned, and whether running at high or low speed, the engine should give a clear and distinct exhaust at every stroke of the piston.

GEARING.

The power of the traction engine is transmitted to the traction wheels by a series of gearing, all of which should be made from accurately cut patterns to insure the teeth meshing perfectly to prevent them from cutting and grinding out, and of sufficient strength to withstand the very rough usage to which they are subjected. The gearing of an engine should never be run without first greasing them thoroughly with a good quality of solid oil or axle grease, for if once you allow the teeth to cut, it will be impossible to stop them from cutting, the result being they will soon be ruined. The gearing on traction engines are placed in many different positions for transmitting the power to the traction wheels, as will be seen by examining the different illustrations given in this book.

On a side gear engine the power is transmitted from a small pinion on the main shaft to an intermediate gear, from this gear to the differential gear on cross shaft which is placed under the cylindrical part of the boiler against the fire box. To this shaft are keyed two small pinions at each end, which mesh in large spur gears fastened securely to the traction wheels.

On a rear gear engine the power is transmitted from the small pinion on crank shaft to large spur gear attached to one end of cross shaft, which crosses the boiler at the rear end. To the other end of this shaft is attached a small pinion that meshes in the large differential gear which is attached to traction wheel and main axle.

DIFFERENTIAL GEAR.

The gearing on a traction engine must be so designed as to allow one of the ground or traction wheels to run faster than the other, when turning engine either to right or left on the road. To accomplish this, the Differential Gear is made use of, and answers all purposes admirably.

The Differential Gear on many styles of engines is attached to the cross shaft, while on others it is secured to the main axle, and, as generally constructed, consists of one large spur gear, having three or four bevel pinions placed in it at equal distances apart and from the center of main gear. These pinions revolve loosely on pins secured to the gear, and the spur gear runs loosely on the cross shaft or axle. At each side of the spur gear are placed bevel gears, meshing into the bevel pinions, one of which is keyed fast to the shaft or axle, while the other is firmly bolted to small pinion that drives the traction wheel, or to hub of the traction wheel, which also runs loosely on its axle.

This device allows one drive wheel to remain idle while the opposite wheel may revolve as fast as is required to make the turn.

Differential Gears should be kept well greased with solid oil or axle grease to prevent the cogs from being cut and wearing away rapidly.

FRICTION CLUTCH.

This attachment on a traction engine is almost indispensable as it allows the engineer to give the whole power of the engine instantly to the traction gear in getting the engine out of bad places, or to move the engine backward or forward with so little apparent effort as to be almost imperceptible, while the engine may be running at full speed; also for tightening the main drive belt when attached to machinery without stopping the engine.

The friction clutch shown in illustration is constructed as follows: The friction pulley is constructed with a friction ring upon its arms, the outer ring acting as a guard or protection, the friction ring being turned accurately to receive the wooden shoes attached to the driving arm; these wooden friction shoes are fitted to the outer surface of the ring as well as the inner, all being connected to one set of levers; so when force is applied to engage the friction to start the engine there is no tendency or danger of bursting the rim, as the pressure is equal on both sides of it. The pulley is keyed to the crank shaft, while the driving arm, with driving pinion secured firmly to it, runs loosely upon the shaft. Upon the hub of driving arm is placed a sliding sleeve with lever attached, which connects with toggle levers beneath the sliding pieces which contain the wooden friction shoes, the whole being operated by the sliding strap from footboard of engine near by the reverse lever. This makes a strong and convenient arrangement for transmitting power.

Many other styles of clutches are made by engine builders, adapted to their particular style of engines, a common way being to have the shoes tighten against the inner rim of the fly-wheel. This is not deemed as good an arrangement, for the reason that the pressure or strain is all outward against the rim, though their being used extensively indicates good results.

When operating a friction clutch, always draw or push the lever over gradually. By doing this the engine will start slowly and easily, while if the lever is jammed over suddenly, the engine will start with a jerk, which is liable to damage the traction gear. The latter should never be done unless absolutely necessary to get the engine out of bad places on the road.

QUESTIONS WITH ANSWERS,

Concerning the Operation and Care of Steam Engines and Boilers.

Q. What should be done first, after receiving a new engine, to prepare it for running properly?

A. If a traction or farm engine, remove the box containing the fittings and tools, from the fire box, and see that the grates are in their proper places. Also take out the tools which are packed in the smoke box at front end of boiler. Then, with waste or rags well saturated with kerosene, turpentine or benzine, wipe off all the grease that the manufacturer has put on to protect the bright work from rusting. After this has been thoroughly done, clean every oil hole and bearing found upon the engine, of all dirt and cinders. Special attention should be given to this, as if dirt and cinders are allowed to remain, the bearings will cut and heat.

Q. After this is done thoroughly, what next?

A. Take all the fittings from the box and clean them carefully, fit each oil cup to its proper place and screw them in tightly with a wrench, to prevent them from working loose and falling off while engine is running on the road.

Fill all cups with good oil, lard oil for bearings, good cylinder oil for the automatic oiler, which oils the cylinder and valve, and solid oil for both grease cups at crank and cross-head. Then put the steam gauge, the glass water gauge, gauge cocks, safety valve, whistle, surface blow-off and blow-off valves, cylinder cocks, governor belt, etc., in their proper places; all fittings should be screwed up tight with a wrench. Examine the stuffing boxes and see that they are all well packed and cleaned.

Q. The fittings all being attached, what next?

A. Proceed to fill the boiler with water by unscrewing the cap from filling plug located on top of boiler near the steam dome, screw funnel on plug, and fill boiler with as clean soft water as is obtainable.

Q. How much water is required in the boiler before starting fire?

A. Fill the boiler until the water shows about one and one-half inches in the glass water gauge, or have a free flow of water from the lowest gauge cock.

Q. After the boiler is filled with water to the proper level, what next?

A. Start a moderate fire with dry wood in the furnace or fire box, and open the draught damper wide. Add fuel slowly, and while steam is being raised take your oil can and wrench and examine the engine thoroughly at all its parts. See that every screw and bolt is tight and that none of the oil holes have been overlooked.

If a traction engine, examine all the gearing and see that all gears, axles and bearings are thoroughly greased and oiled—grease for gears and axles, oil for bearings.

If firing with coal, keep the grates well covered with a thin layer. Do not throw in large lumps or too much fresh coal at one time. A thin fire lightly and frequently renewed, is the most economical.

Q. Is the natural draught of the boiler enough to enable steam to be raised quickly?

A. No. The boiler and water being cold the fire will not burn briskly, but as soon as steam pressure shows upon the steam gauge, turn on the blower, which will force and increase the draught; then with good fuel, any desired steam pressure can be raised quickly.

Q. Must the blower be used when the engine is running to keep up sufficient steam pressure?

A. No. When the engine is started, the exhaust steam is discharged from the cylinder first through the heater, then into smoke stack, producing the same effect as the blower.

Q. If the boiler steams too fast, what should be done?

A. Simply close the damper. Do not open the fire door, as the fire door should never be opened unless absolutely necessary, nor should it be kept open longer than is needed, as the cold air admitted through it injures the boiler and is wasteful of fuel.

Q. After sufficient steam is raised, how do you proceed to start the engine?

A. Before turning steam on the engine, go to the fly-wheel and turn it a few times to see that everything is all right and no obstacle in the way to prevent the engine from running when steam is applied, being sure to leave the crank-pin off the center to enable the steam to start the engine when throttle valve is opened. Next, open both the cylinder cocks, then the throttle valve just a trifle to allow a little steam to enter the cylinder, to warm it and expel the water of condensation. Then open the throttle gradually, and if everything is right, the engine will move off faster and faster until the proper speed is attained. After engine is thoroughly heated and is working dry steam, close the cylinder cocks and set the automatic oiler to work.

Q. How do you obtain the proper speed, and how is the engine made to run steadily with the steam pressure so varied?

A. The proper speed and steadiness in running is maintained by the use of the governor, which receives its motion from the engine shaft by means of a belt.

Q. Are the bearings of a new engine liable to heat when first started up?

A. Not if proper attention is given to them. When starting a new engine the first time, it should be stopped frequently and the moving parts and bearings carefully examined. Feel of all the bearings, the link block, the eccentrics, crank-pin, cross-head, etc., to ascertain if they are heating. If they are, slacken up the boxes a little, but not enough to make them knock or pound. Always be careful not to loosen or tighten bearings or keys too much; just a trifle at a time, but do it often, until the bearings and boxes run cool, but tight. If this is done carefully, the engine will run smoothly and quietly.

Q. After the engine is started, what should be done next?

A. Fill the tank on the engine with water and start the injector to work, so that the proper level of water may be kept in the boiler. The independent pump, if used, should now be fitted, connected and tried, to see if it is in proper shape to feed the boiler. If a cross-head pump is used, it should be fitted and attached to water supply with the suction hose. In this case when the engine is running, the pump can be regulated to supply the required amount of feed water.

Q. How is the boiler supplied with water while the engine is stopped?

A. By the independent pump or injector.

Q. Has the independent pump sufficient capacity to supply the boiler with water under all conditions?

A. Yes, always, when running at a reasonable speed.

Q. Why should an injector be furnished if the pump will supply the boiler?

A. Many times through carelessness or otherwise the pump is prevented from working by dirt, straw, chips and other obstructions which find their way into the pump and hold the valves from their seats. In this case it is necessary to take the pump apart and remove the obstructions wherever found, which would necessitate stopping the engine and allowing the steam to go down, involving a large loss of time. Whereas if the engine is also supplied with an injector, should the pump fail, the injector can immediately be started and the pump examined at leisure without loss of time and avoiding all danger of explosion.

Q. Should the supply of feed water be continuous while the engine is running?

A. Yes. Gauge the speed of the independent pump so that it will furnish the required amount of water to the boiler. Regulate the feed of a cross-head pump, by the suction valve. By so doing, the boiler steams easier, the flues are not so liable to leak, and a uniform steam pressure can be easily maintained more economically.

Q. How is a boiler supplied when engine is in motion?

A. By the independent or cross-head pump.

Q. When should the injector be used in preference to the independent pump?

A. There being no exhaust steam when engine is not running, no benefit is derived from the heater. Now, as cold water should never be forced into a hot boiler the injector becomes of great value, as it heats the feed water to a very high temperature before it enters the boiler.

Q. Is there any independent steam pump made that heats the feed water before it goes into the boiler?

A. See Marsh Pump description.

Q. When engine, pump, and injector are found to be working properly, what next?

A. If a traction engine, the engine should be reversed several times. This can be done by throwing the reverse lever forward and backward, to ascertain whether the valve is so set that engine will run equally well both ways; then the traction gear may be tried. If engine is supplied with a friction clutch, by simply pressing the clutch lever gradually until the friction shoes take hold, the engine will start slowly upon the road. This can be done while engine proper is running at full speed.

The clutch lever should be held in one hand when first starting, so that in case of anything being wrong with gearing, it can be stopped immediately by quickly loosening the lever. With the other hand, the steering wheel should be operated to guide the engine upon the road. When all is found to be working properly, and you wish to run the engine any distance, the clutch lever should be placed in notch provided for it; this will hold the friction shoes securely to the wheel, and the engine will move along the road at full speed.

Q. If the engine has no friction clutch, how do you proceed to start the gearing?

A. Stop the engine and place the reversing lever in center notch, slide the spur pinion on main shaft into gear and open the throttle valve wide; then with the reverse lever in one hand (the steering wheel in the other) you can start engine upon the road by throwing the lever backward or forward, which should be done gradually at first, so that engine will start slowly. If all is right, by throwing the reverse lever in the last notch in quadrant, the engine will travel its full speed upon the road.

Q. How should a traction engine be first started upon the road, forward or backward?

A. Always forward, as you can see where you are going and can guide the engine more easily.

ADVANCE TRACTION ENGINE.

In illustration is given the engine side of the Advance Engine, which is of the side crank, side gear type, with the engine placed at forward end of boiler.

The cylinder is overhanging, and is bolted to the cylindrical formed engine frame which forms the front head. The frame is attached to the boiler with two brackets, and it contains the bored cross-head guides and pillow block bearing.

The engine has the Marsh Reverse Gear, Marsh Pump, Friction Clutch attached to band wheel, Injector, Governor and all necessary fittings.

The boiler is the locomotive round bottom fire box style, with dome in center. It is mounted upon the traction wheels with axle arms attached to brackets bolted to the sides of fire box, in which are placed springs.

The spokes of the wheels are cast in both hub and rim, the latter having mud cleats cast on. The platform has both Water Tank and Tool Box attached, and the steering wheel and band wheel are on the same side of the engine.

The chains for the steering attachment are supplied with springs.

Q. How should you guide a traction engine?

A. There is no fixed rule for guiding a traction engine upon the road. It must be learned by experience. Good judgment is required to make a success of it. One man should always handle both reverse lever and steering wheel when guiding an engine.

Q. How should the steering chains be put on a traction engine?

A. The chains should be so put on, that when the steering wheel is turned to the right, the engine turns to the right; when wheel is turned to the left, the engine turns to the left.

REVERSING AN ENGINE.

To reverse the motion of a plain Slide Valve engine, remove the cover of steam chest and place the engine on the dead center. Observe the amount of lead or opening that the valve has on the steam end, then loosen the eccentric and turn it around on the shaft, in the direction the engine is wanted to run, until the valve has exactly the same amount of lead at the other end; then turn the engine to the opposite center, to determine whether the lead at this end is the same as at the other; then place the crank at half stroke top and bottom, and see that the port openings are equal in both positions, and replace cover.

Q. What is dead center?

A. The dead center of an engine is the point where crank and piston rod are in an exact line.

Q. What is a half stroke?

A. It is the point reached by the piston after traveling exactly one-half its travel.

Q. What is the meaning of “lost motion”?

A. Lost motion is looseness of the connecting rod at crank or wrist-pin, or looseness of the link or link block, cross-head and guides, main crank shaft and pillow block, caused by friction and wearing away of the metals and the neglect to take up the wear.

The lost motion in all parts of an engine should be taken up frequently, to keep it running smoothly, but care must be taken not to tighten bearings or keys too tight.

Q. What is lap and lead?

A. Lap is the position of the valve which extends or laps over the edge of the ports when the valve is in its central position. That on the inside of the D is the inside or exhaust lap, while that at the ends of the valve is the outside lap and affects the admission and cut-off.

Lead is the amount of opening which is given to the port by the valve when the engine is on the center.

Lead on a valve is the admission of steam into the cylinder before the piston completes its stroke.

Q. How much “lead” should a valve have?

A. There is no general rule for the amount of lead that would be best suited for all makes of engines. It must be determined by the design or construction, speed and work required, to produce the best results for economy and quietness in running.

Q. What is a throttle engine?

A. A throttle engine is one in which the speed is controlled by throttling the steam with a governor, as opposed to an automatic engine in which the speed is regulated by varying the point of cut-off at the valve.

Q. What is the difference between a stroke and a revolution?

A. A stroke is the movement of the piston, from one end to the other of cylinder. A revolution takes two strokes of piston.

Q. How are steam packing rings put on the piston head?

A. Remove the back cylinder head and take the piston and rod out of the cylinder, and stand it “head up.” Then place the inside of the ring, opposite to the opening, against the side of the piston head next to you; gradually press the ring open with your hands, and it can be easily slipped over the head and put in place.

Q. How is a piston put into cylinder?

A. It is always entered from the back end in horizontal engines. The rings (if steam packing) should be carefully placed in position and compressed by the hand if piston is small, but if large, curved blocks of wood or a band of sheet iron can be used to support them until they enter cylinder. When the piston rod passes through the stuffing box, it should be supported at outer end to prevent cutting.

WATERTOWN HIGH SPEED ENGINE.

The frame of this engine is very heavy, with longitudinal and cross ribs securely bracing it. It forms the lower guide for cross-head, and contains the pillow block bearings at the front end. It also forms the front cylinder head, to which the cylinder is bolted. The working parts are placed as low in the frame as is possible, so that the strain is brought in line with the line of greatest resistance.

The double disc center crank shaft allows of two small heavy band wheels, one of which has the shaft governor attached to the inside, that operates the valve automatically to give the point of cut-off in accordance with the variation of load.

The valve is of a special design, and so constructed as to admit steam to the cylinder port through four different openings. It also exhausts steam through four different openings at once.

The engine frame rests its whole length and is securely bolted to the sub-base, which is bolted to the floor, and the smaller sizes need no elaborate foundations.