Great Falls tribune. [volume] (Great Falls, Mont.) 1921-current, 1922-12-24
ENGINE IN AUTO
TEMPERMENTA[
As OPERA STAR
Ignition at Right Moment and
Compression Needed for
Start.
Nv y. CLIFFORD o K


Bv a, CLIFFORD BRoKAW
The mechanical movements OF the
motor in an automobile can be relied
on to function properly if all the con-
ditions are just right. But a gasoline
~engine is as temperamental as an opera
singer.
A gasoline engine is apt, at tines
to appear thus temperamental even To
an owner who has mastered the pfln-
ciples of its operation: rms Is espe-
lcialIy true in starting the thing Hneh
it comes to getting a motor TO moving
it insists on at least three condltlons.
No matter how fine an engine 1T IS,
how we'll trained, how good looking, or
how many cylinders, these conditions
mist be met before the machine Will
rive the first consideration to starting.
otherwise it will only fuss and sputter
and the owner is quite apt to do IKE
wise.
The three things which are neces-
sary tn start the engine of an utomo-
lille are a proper mixture of gasoline
and air. ignition at the right moment
and compression. Gasoline will con-
tinue to burn after ignition, but. con,
trary to the general opinion, 1t Will
not explode unless confined, and not
even then unless it has vaporized and
the vapor is mixed with air. 1t takes
about 200 cubic feet of air to a pint OF
gasoline vaporized to produce good
combustion, though the air supply is
usually much more than this to insure
CARRYING off the unburned nitrogen
from the air. For starting and speed
ing up. more gasoline is admitted to
the vaporizing chamber, as the rich
mixture ignites more quickly. but for
running a leaner mixture produces bet
ter results.
Power for Driving Car
Whatever the mixture which Is
burned there would be little or no pow
er produced if the mixture were not
confined under pressure. A tank filled
with gasoline vapor and air will ex-
! plode with great force if ignited.
, though there be only the ordinary at
mospheric pressure upon the tank. But
it must be remembered that If the
pressure were 50 or 20 pounds to the
square inch the explosion would de-
stroy everything in the vicinity. There
fore, the designers of the gasoline en-
CINE provided for COMPRISING the gas
before ignition, to produce the greatest
amount of power for driving the car.
Valves are provided which admit the
charge of mixture to the combustion
chamber, closing tight after the charge
is received.
Then the piston rises. COMPRISING
the contents of the combustion ham
Der until a pressure of between 40 and
IS pounds Il square inch is reached.
Just as the piston reaches the high
est point. and the compression is at the
maximum. n spark is introduced into
the combustion chamber. Under the
pressure the gases burn much more
rapidly and the explosive force is great
err. The gas does not burn ~instantane-
ously, however.
A distinct interval of time is re-
CURED for all the gas mixture to
ignite. For this reason, when the en-
CINE is running under its own power,
the spark comes just before the time
of greatest pressure, and before the
piston reaches the top center, so that
by the time the piston starts the
downward stroke the highest efficiency
of power will have been reached.
Therefore, the spark-timing control
lever should be advanced after the en-
CINE is started to give the best re
suits. But the engine should be al
ways started with the spark fully re
tarded.
In the meantime the carburetor has
been called upon to send into the com
bustion chamber through the intake
manifold and intake valves n charge
of gas mixture. The quantity is regu-
lated by the throttle. When starting.
the ~carburetor should be "choked,"
that is. the air supply should be partly
cut off. causing an extra supply OF
gasoline to be drawn into the mixing
Chamber. thus making the mixture
richer and more readily fired. When
the engine has started running. the
throttle is closed to Il point where the
motor does not race.
l~anitIon System junction
The ignition system must deliver to
the combustion chamber at the right
instant q spark of sufficient intensity
to fire the charge. Whether the
electric current is obtained IRON bat
terry or magnetic, it must De not
enough to do it's work and there must
be n timing device which Will send the
spark into each cylinder when II IS
needed.
The compression is maintained
when the piston rings and grooves are
free from gummed oil or carbon and
mova freely. when the cylinder walls
nre NOT worn oval by n slapplng piston
or creased by carbon. when a film OF
lubricating oil is constant on the side
wallis and when the valves are prop
erly seated. Loss of compression
means loss of power II the GYM
ders should be tested every little
while to make sure that no cylinder Is
failing to do its duty. No.
Having started the engine, three
more, things are required to keep the
thing going. There must be a cool-
ing system of fabrication and a Tree
exhaust. When the owner under
stands the simplicity of gas-eng'ne
operation, he can begin to trace each
part of the operation. He viii know
why the engine will not start II It
will not, and why it stops on the road
if it does.
During the fall and winter months
it is usually a little more difficult to
start an automobile than in warmer
weather. This is due to the fact that
the mixture lacks warmth and conse-
ouently condenses when it strikes the
cold cylinder walls. This is usually
overcome by printing the engine and
choking the carburetor. It may, how
ever, help to put hot water in the
radiator. Once the engine is gong IN
cold weather and the machinery gets
warmed up, it is apt to run as well as
any other time.{ 49,,
An owner will learn after a little
ayneripnre whit are the tempera-