Medical Society of the State of North Carolina. An.

Cyclopedia of automobile engineering; a general reference work on the construction, operation, and care of gasoline, steam, and electric automobiles, instruction in driving, commercial vehicles, motorcycles, motor boats aerial vehicles, self-propelled railway cars, etc online

. (page 26 of 27)
Online LibraryMedical Society of the State of North Carolina. AnCyclopedia of automobile engineering; a general reference work on the construction, operation, and care of gasoline, steam, and electric automobiles, instruction in driving, commercial vehicles, motorcycles, motor boats aerial vehicles, self-propelled railway cars, etc → online text (page 26 of 27)
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themselves. Most of it is likely to be in the differential gears, which
are hard to examine directly. It is usually safe to assume that these
will need replacements anyway. If the cardan joints are loose,
they should also be replaced or rebushed.

Take off the gear case cover and examine the gears with the
aid of an electric light, feeling of tha teeth if necessary. Certain
gears are likely to be much more worn than others, and if the teeth
have lost their rounded profile, or if their sides have been worn away
where they strike each other on shifting, new gears should be sup-

Run the engine and note its sound. It should be reasonably
quiet when running idle on low throttle, and should not be excessively
noisy when accelerated. It should be free from periodic knocks,
one per revolution or one every other revolution. If a knock is heard,
endeavor to trace it by pressing one end of a stick against the casing
near the suspected part, the other end being held against the chin.
Stopping the engine, shake the valve stems and valve lifters between
thumb and finger to test their looseness. The valve stems will bear
some shaking, but if the valve lifters are loose they will be noisy.

When the car is run for demonstration, listen for nosies, as
these are the truest index to its condition. If the engine knocks
when pulling up hill, either the bearings are loose or there are carbon
deposits on the piston heads. If the engine runs hot on hills, the
radiator or piping may be clogged or the ignition may be irregular.
Note whether the transmission gears are noisy when transmitting
power, also note whether gear shifts are made easily and quietly.


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If high gear engages noisily or with difficulty, it is probably due to
the teeth of the jaw clutch being worn rounded.

Take advantage of the demonstration run to test the engine power
on hills, the flexibility of the engine — i. e., its ability to slow down
in high gear without stopping and pick up again when the throttle
is open — also the holding power of the clutch and brakes. Remem-
ber, however, that the engine power is largely a question of carbureter
and ignition, and if either of these are faulty the engine will not show
its real capabilities. Remember also that worn brakes may be re-
placed, but that, if lack of holding power in the brakes is due to small
size, it cannot'be materially improved.

Much depends on whether the car is offered as being in first-
class condition and ready to run, or whether the purchaser expects
to overhaul it at his own expense. In the former case the car may
properly be debited for any weakness in performance, while. in the
latter case the purchaser must be a good judge of cars to note how far
the seeming defect may be overcome. Many an engine has been re-
juvenated simply by putting on an up-to-date carbureter and ignition
system, or merely by correcting the valve timing.

If the car is supposed to be perfect as it stands, the demonstra-
tion run should not be too short — a twenty to fifty mile run should in
most cases be insisted on. At the end of the run, test the com-
pression by turning the crank slowly with the spark cut off. If the
cylinders do not hold compression well, new piston rings are likely to
be necessary, since it may be assumed that the valves are in good

In appraising the value of a second-hand car, do not lay too
much stress on what the car was worth when it was new. If it is
several years old, equally good cars are to be had today for half or
two-thirds as much money. Assume, therefore, that the car under
consideration was worth when new as much as similar cars today,
and then scale its price down, according to the wear it has received
and the probable cost of putting it in good condition. Remember
that, even when the engine, transmission, and steering gear have
been thoroughly overhauled, there will be numerous minor bearings
all over the car which in the nature of the case can hardly be replaced
save at prohibitive cost. Such are the joints of the steering mechanism
the gear^shifting mechanism, the brakes, the radius rods, etc. All


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of these, gradually wearing loose, will in time make the car noisy,
even when the power plant is in excellent condition.

When the condition of the car has been ascertained, estimate
as nearly as possible what it will cost to overhaul it. Add the cost
of new tires where needed, and credit the car with the value of extra
equipment, if any. Then compare the total prospective cost of the
car with the total cost of a similar new car fully equipped, and make
suitable allowance for the wear and tear the car has already had.
In this way a fair appraisal of the car's value may be obtained.

Steam. In selecting a second-hand steam car, the first thing to
remembei; is that, from the nature of their mechanism, steam cars
do not usually last as long as gasoline cars of equal mechanical quality.
A high-grade steam car, for example, will be worn out in three or four
years, whereas an equally good gasoline car would last twice as long.
The reason for this is partly that the boiler or generator and the
various auxiliaries, automatics, and fittings under pressure wear out
somewhat rapidly, and partly that the engine, since it develops more
power in smaller compass, necessarily tends to wear itself out more

A steam car requires the same examination of the mechanical
parts for wear that the gasoline car does. For example, the steering
gear, the propeller shaft, or sprockets and sprocket chains, the bear-
ings in the front and rear wheels, the rear axle and the brakes, should
all come in for examination. The propeller-shaft-cardan joints of
a steam car wear out much more rapidly than those of a gasoline
car, due, probably, to the fact that the steamer cannot, like the gaso-
line car, be unclutched momentarily when going over rough spots.
Every road jolt involves a more or less abrupt, momentary change
in the angular velocity of the wheels and transmission shafts. If the
wheels are disconnected from the engine there is only the inertia of
the clutch to be overcome, but with the two rigidly connected the
transmission members must stand the whole jerk, transmitted from
the wheels to the engine.

Have the car fired up in your presence, noting the procedure
and how long it takes. Notice if the burner and pilot flames are hot
and clear blue in color. After the water is worked out of the engine
run the car with the front wheels against a wall, and open the throttle.
If steam escapes from the exhaust it shows that the slide valves or


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piston rings leak. Notice how long it takes the power air pump
to raise pressure. If the tank is full it should take but a few moments ;
if the pressure comes up noticeably slowly, the air check valves prob-
ably leak.

If the country is hilly, test the steaming power on the hills. No-
tice whether the fire comes on and oflf cleanly in response to the
automatic control. If the burner lights back, insist on having the
trouble corrected before you accept the car. A White steamer with
flow motor should require very littie running to enable it to take a hill.
Other types of steam cars must have the throttle opened long enough
before striking the hill to insure the fire being on when the foot of
the hill is reached.

Note how far the engine can be hooked up when running fast.
If the engine pounds with late cut-oflf on low throttle the bearings are
loose, or the valves are improperly adjusted. ' Loose cardan joints in
the propeller shaft will rattle under the same condition, especially
just when the throttle is opened.'

Electric. When selecting an electric vehicle, first investigate
the condition of the mechanical elements, i. e., gears, bearings in
wheels and transmission, steering gear, commutator and brushes.
Examine also the controller to see how far the contact segments are
burned away.

Aside from the above, the main question is the condition of the
battery, arid this can only be fully settled by an expert. The user,
however, can satisfy himself fairly well by having the battery fully
charged^ and then making a test run of the machine, say at twelve
miles speed, over smooth level roads till the charge is exhausted. The
ideal test will be to run the car over average roads such as will be met
in service, but this might involve a troublesome tow at the end of
the test. The alternative is to run it around the block. When the
voltmeter shows that the battery is discharged to 1 . 8 volts per cell,
the mileage should be noted. Before and after the nm the voltage
of the individual cells should be tested. If any cells are found
defective it is best to allow for the cost of new cells.

It will be good policy to remember that any lead storage battery
is only good for a limited number of charges (usually 40 to 50
complete charges and discharges). Furthermore, although the
eflBciency when new is nearly 80 per cent and holds up well for the


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first dozen or twenty charges, its capacity thereafter diminishes
almost in proportion to the number of discharges.


New Car. The beginner with a new car is strongly tempted to
plunge at once into hundred-mile rides and week-long tours. This is
a mistake in several ways, chief of which is that it is a strong invita-
tion for trouble in case something goes wrong with the 'car. Until
one understands every detail of the machine, and particulariy the
details of ignition and carburetion, a very trivial mishap may present
formidable perplexities.

The subject of learning to drive is dealt with in another part of
this course, but even the owner who already knows how to drive has
something to learn about the pecularities of any new car that comes
into his hands. Before attempting to drive, one should learn every-
thing possible about the four cardinal points, ignition, carburetion,'
Ivhrication, and the gasoline tank, pipe and shut-off valve.

Learn whether ignition is by magneto or by battery, and if the
former, whether the magneto is of the true high tension type or a low
tension magneto with step-up coil and distributor. A few cars have
make-and-break igniters with low tension magnetos. The action of
these igniters should be thoroughly studied, and one should know
how to remove the igniter plates to clean soot from the inner insula-
tion, and also how to adjust the timing, so that all will fire at the same
crank angle. Learn if there is a battery for starting purposes, and
what is the retarded position of the spark lever. If batteries are
used, test them to see that they are not exhausted when you get
the car.

Examine the carbureter to see how it is primed for starting.
Some carbureters are primed by depressing the float, others by closing
a choke valve at the carbureter intake. If the careburter has a hot-
water jacket, look for the valve which controls the water circulation
through it. If there are adjustable hot- and cold-air intakes, see that
they are adjusted according to the season.

Familiarize yourself thoroughly with the lubrication system
of the engine. If oil is fed by a mechanical oiler through individual
pipes to the bearings or crank case, see that all the pumps of the
mechanical oiler are working, and that none of the oil pipes leak at


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their joints and unions. If oil is circulated from the crank case to
the bearings and back again by a pump located at the base of the
crank case, take out the screen through which the pump draws oil
and see that it is clean. Probably the crank case or oil reservoir has
a test cock at the proper oil level; see that oil of the proper grade is
poured in until it comes out of this cock when the latter is opened.
Some large cars have the main oil tank located back of the engine
under the footboard, and oil is pumped from this to an auxiliary tank,
or to the mechanical oiler. If there is such a tank, locate it and see
that it is' filled.

If the clutch runs in oil, learn from the makers what grade of oil
is used — it may not be the same in summer and winter — and see
that the proper quantity is supplied.

Ascertain what lubricant is proper for the transmission gears.
If the gear shafts run in ball or roller bearings throughout, thin
mineral grease is dangerous for the reason that it cannot be trusted
to work its way through small oil holes. Many gear cases have anti-
friction bearings throughout with the exception of the "pilot" bear-
ing inside the main driving pinion. In this bearing runs the front
end of the squared or feathered shaft, carrying the sliding gears,
and for lack of room it is often plain bushed. With grease lubrica-
tion, such a bearing is liable to cut; heavy "gear case'* oil must there-
fore be used.

Usually the cardan joints of the propeller shaft are encased
and filled with thin grease, and sometimes they have individual
grease cups. Looseness in the cardan joints is at least annoying, and
due attention should be paid to their preservation from wear.

The rear axle casing is usually filled one-third full with gear case
oil, to which in summer a littie grease may be added. Thick grease
is undesirable, as it sometimes fails to work into the bearings of the
differential pinions, and these, therefore, get dry and cut. If too
much oil is put into the axle casing, it will work out to the wheeb and
get on the brake drums.

The numerous grease cups and oil holes scattered about the car
are quite as important as the major lubricating systems. A car
whose engine or transmission is worn out may be overhauled at mod-
erate cost by putting in new bushings and gears, but when worn out
in respect to the minor bearings it is nearly hopeless; for, except in the


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highestrpriced cars, these are seldom bushed or otherwise fitted to
take up wear. Therefore the grease cups should be given a turn
each day when starting out, and refilled when necessary, and the
oil-can should be used as indicated.

Ascertain the location and capacity of the gasoline tank, and
note whether the carbuteter is fed by gravity or by air or exhaust
pressure. Learn where the shut-off valve is, between the tank and
the carbureter, and make a practice of closing it after every run. Few
carbureter float-valves are so tight that they permit no leakage what-
ever, and the fact that the carbureter does not leak today is no guar-
antee that it will not leak tomorrow. If pressure feed is used, famil-
iarize yourself with the pressure relief valves between the exhaust
manifold and the tank, and the pressure gauge on the dashboard.
The stramer or separator, which prevents water condensed from the
exhaust gases from getting into the gasoline tank, should also be
noted, and the method of cleaning it understood.

One is under no obligation to assume that a new car fresh from
the factory is likely to go wrong in the first hundred miles. Never-
theless, it frequently happens, especially with the cheaper classes of
cars, that one or another minor detail may not be up to the standard
of the car as a whole. For example, the battery box, if of wood,
may be strong enough to hold dry cells, but too flimsy to hold a heavy
storage battery. The ignition may be hastily installed, the spark and
throttle connections may be a trifle too long or too short to give the
full range of control, and there are numerous other possibilities of
minor trouble which the user may need to find out and correct be-
fore he gets the best service from his car. It is always best for the
first few weeks to keep fairly close to home and help, till one is satis-
fied that these possiblities have been eliminated, and the car as a
whole is fully "tuned up" to its work.

Second-Hand Car. The remarks of the preceding chapter on
getting acquainted with a new car apply with three-fold force to the
used car whose exact condition is not fully known, and which is prob-
ably not accompanied by the maker's book of instructions. In addi-
tion to all the precautions enumerated above, one must be on the alert
for signs of possible defects. Unusual sounds in the engine should
be investigated. They may be due to irregular firing, to looseness
of some bearing, to heating up, or to other causes. The remedy is


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not usually difficult to prescribe when the cause is known. The
radiator should be watched for leaks and felt by hand to determine
whether the water is circulating properly. The gasoline pipe and
carbureter should be watched to see that there is no leakage. Occas-
ionally a pipe union or the carbureter itself may leak, but not enough
to cause noticeable dripping. Touching the fingers underneath,
however, will tell the story.

Be sure that the engine gets enough oil. Until you know posi-
tively that the oiling system is working properly, it is better to feed
the engine too much than too little. If a mechanical oilej* with indi-
vidual feeds is used, it is a safe plan to disconnect one oil pipe at a
time, where it goes into the engine, and note by running the engine
whether oil comes through it or not. If the engine smokes, it is a
good sign that it is getting enough oil. Sometimes, however, the oil
eed may be such that one or two cylinders may be starved of oil
while the others get enough or too much. This will usually be shown
by the smoke puffs of the exhaust being intermittent instead of
smoothly continuous. • If the cylinders are separately oiled, the defi-
cient one may be traced by disconnecting the oil pipes at their ends.
If they are oiled by splash the forward or rear part may not get its
share, owing to the oil being low in the forward or rear oil pan.
Some engines have individual pans or troughs, one under each cylin-
der. These should be arranged so that oil entering one will distribute
itself to the others as soon as the proper level is reached. If, how-
ever, there is not enough for all, one or two may be starved. If the
oil is circulated by pump from an underneath reservoir, there is not
much danger of any of the cylinders being starved, as the pump
throws many times the permissible minimum supply. When one
is satisfied that no part of the engine is being deprived of oil,
the feed may be reduced gradually until there is only a slight show
of smoke in the exhaust.

As one does not usually know when buying a second-hand car
what is the state of the oil in the transmission and rear axle, it is
best to clean it out altogether and supply fresh oil. One should by
no means use the car to any extent till satisfied that all the gears
are properly lubricated.

The brakes should be examined for wear, and if taken up nearly
to the limits of their adjustment they thould be refined.


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Aside from the foregoing specific points, watch should be kept
all over the car for things working loose — ^for example, the various
joints, etc., of the steering gear, the bolts holding the base of the
steering column to the frame, the spring clip bolts, the holding-down
bolts of the engine, and the various parts of the propeller shaft,
cardan joints, etc. If cotter pins are missing they should be supplied
at once. If any particular nut or bolt betrays a chronic tendency to
loosen, special means must be found to lock it. It will usually be
found that the trouble lies in the bolt being too small to fill its hole,
or in not being prevented from turning.


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In the foregoing sections of this Cyclopedia nu-
merous illustrative examples are* worked out in
detail in order to show the application of the
various methods and principles. Accompanying
these are samples for practice which will aid the
reader in fixing the principles in mind.

In the following pages are given a large num-
ber of test questions and problems which afford a
valuable means of testing the reader's knowledge
of the subjects treated. They will be found excel-
lent practice for those preparing for Civil Se^ce
Examinations. In some cases numerical answers
are given as a further aid in this work«


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1. Name the principal working parts of a simple double-
acting steam engine.

2. Define radiation, absorption, conduction, and convection.

3. State Boyle's Law.

4. What is absolute zero? What molecular state does it
theoretically represent?

5. Define force, work, and power. What is a horse-powerf

6. Define British thermal unit.

7. Define latent heat. How many British thermal units are
absorbed in boiling away a pound of water at atmospheric pressure?

8. Why is the explosion of a stationary boiler so .destructive?

9. Define superheat. What is its object?

10. Sketch roughly a D slide valve.

11. Define lap and lead. What is the angle of advance?

12. Describe the Stephenson link motion, and give a rough
sketch of the same.

13. Under what circumstances is gasoline vapor explosive?
How may it be ignited?

14. Describe the construction of the Stanley boiler.

15. What is a fusible plug, and what is its purpose?

16. How is the fire regulated in the Stanley and Lane cars?

17. Explain the principle of the thermostatic water-level in-

18. How should the throttle of a car with fire-tube boiler be
managed on approaching an up-grade? A down-grade?


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19. Describe the general process of firing up a car with fire-tube
boiler and getting ready to run. In what particulars is caution
especially necessary?

20. What is the object of blowing down the boiler, and when
should it be done?

21. How is the boiler most easily filled with water for the next
firing up?

22. What is the most frequent cause of low pressure and its

23. Describe the arrangement of gasoline pressure tanks in
the Stanley car. How does the driver know when additional air is
required in them?

24. Describe the use of the blow-off valve in firing up the
Stanley car.

25. State two possible causes of the Stanley water pump failing
to work.

26. State two possible causes of poor fire in the Stanley car.

27. When starting from rest, in -a car having a compound
engine, what else must the driver do besides opening the throttle?

28. Name the principal packings which need adjustment, and
state which should be packed tight and which may be slightly loose.

29. Besides the hand by-pass valve, what other device has the
Lane car for controlling the water feed?

30. What must be done to lay up the Lane or Stanley cars in
freezing weather?


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1. Describe briefly the flash steam generator. State fully the
particulars wherein its action diflFers from that of the fire-tube boiler.

2. In the theoretical (extreme) case what is the reserve capacity
of the flash steam generator?

3. Referring to the \Miite system of 1904 to 1905, state (a)
how the water supply was regulated; (6) how the burner was regulated.

4. State the two chief drawbacks of the \Miite system of that

5. Draw a rough sketch of the flow motor and name the prin-
cipal parts.

G. \Miere is the thermostat located, and what is its action?

7. Describe clearly the action of the flow motor and thermo-
stat (a) when the pumps are nmning fast enough to force the flow
motor piston to the end of its travel; (h) when the pumps (and there-
fore the car) are running slowly.

8. \\Tiat is the emergency gear, and how is it operated?

9. In what respects do the fuel arrangements of the 1909
and 1910 White cars differ?

10. What is the warming-up valve, and what is the course
taken by the fuel after passing through it? Does the warming-up
valve of the 1910 car take gasoline or kerosene? How long should
the warming-up valve be kept open? •

11. WTien empty how is the generator filled with water? How
may it easily be filled on finishing a run?

12. Describe how to light the pilot light.


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13. State die several steps necessary to start the car from cold,
raise air pressure, and warm up the engine.

14. Should the burner valve be left open or shut, when the

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Online LibraryMedical Society of the State of North Carolina. AnCyclopedia of automobile engineering; a general reference work on the construction, operation, and care of gasoline, steam, and electric automobiles, instruction in driving, commercial vehicles, motorcycles, motor boats aerial vehicles, self-propelled railway cars, etc → online text (page 26 of 27)