Evening star., 1921-12-04
BY ALBERT n. ATKINSON.

BY ALBERT n. ATKINSON.
There are, SO many parts composing
an automobile that they must be
grouped and classified before they
can be understood. When their pur-
pose is grasped it will be easier to
care for and keep them in proper
working condition. At.
The most convenient classification
Oh .ns rse s Soay hs is Seey %e R shs
and SO need not be described. 1t is
bolted to the frame and is made in
many forms, for summer or winter
use, and of greater or less capacity,
depending on the service required.
chanical parts remaining are grouped
under the name Of the chassis"
Four Parts Of the Chassis.
The chassis may be conveniently
divided into four parts: u The
power plant. (2) the transmission.
(s) the running gear. 10 the steer
CD The power plant is the part
which makes an automobile of the
mechanism. Without the power plant
the car would have to be moved by
outside power and would no longer
means a ''self-mover." or car which
runs under its own power. The pow
err plant is the most complicated part
OF the car. requiring special study
and more care than all the other
parts combined. 1t consists of the
engine and five auxiliary systems:
the fuel system. ignition system. oil
ing system. cooling system and the
starting and lighting system.
The Engine.
The engine is the most important
part. as it is the one that makes the
power. 1t consists of the cylinders
and a long list of essential parts.
which will be explained later.
The fuel system provides the gaso-
line. vaporizes 1t. mixes 1t with air
In proper explosive proportions and
delivers the mixture to the engine.
compressed gas in the cylinders at
, the proper time. 1t has been the
study Of experts for many years to
get hot spark at the proper time
IN each cylinder. and although the
System is very nearly perfect it still
requires constant care to keep it at
all times. at its best.
The oiling system supplies a film
of oil between all the bearing sur
faces of the engine. and SO reduces
friction and loss of power and, of
course, prevents the parts from heat
ing and "seizing"
The cooling system prevents the
cylinders from becoming so hot that
they will burn up the oil and damage
the moving parts.
. The starting and lighting system
is a recent development which is now
considered a necessity. 1t enables us
to crank >the engine by pressing on
pedal instead of spinning the start
ing handle by hand. This pedal closes
a switch SO that the current from the
battery passes into an electric motor.
called the starter" which cranks
the engine. AS the starter and the
ignition system use a great deal of
current. this must be replaced as fast
is provided. AS the battery ha. am
pie capacity. it also provides current
Tor the lights-and the horn.
Transmission.
--f2) The transmission is the set of
parts which takes the power from the
power plant and delivers it to the rear
wheels 1t consists of. the clutch,
which is merely convenient means
Of connecting and disconnecting the
engine and the transmission: the
change speed gear set, which gives us
the different forward speeds and the
reverse: the universal joint Gone or
two); the drive shaft: the differen-
tai, which drives the rear wheels at
different speeds going around corners
and at the same speed going straight,
and the live axles. which deliver the
power to the wheels
The Running Gear.
(0 The running gear consists of
the wheels and bearings, the brakes,
the springs, the torsion and radius
rods and the frame which holds all
the parts together in one mechanism.
The Steering Mechanism.
tH The steering mechanism con-
sists Of those parts which control the
front wheels-that is. the steering
wheel. the steering column. the steer
ing gear, the Pittman arm, the drag,
link, the steering knuckle and the tie
rod extending across the car. which
ties one knuckle to the other. so as to
move both wheels together. These
parts must be studied on the car in
order to be understood.
Our next study will be the parts OF
the engine and the function Of each.
Nete-Cut out and save this article
for reference. 1t 10 the first Of ne.
ries, one to follow each Sunday. The
whole series will comprise q course
OF automobile Instruction which will
be Invaluable to every m0torist.