New-York tribune., 1920-01-25

article will he on trarsmissions
There may be perfectly good en-
cine III your car. the gears and brakes
and tires and other members may be
III that could be desired, but unless
.he engine works the car never Will
get anywhere. Il would be interesting,
20 know Just how many OF the million
motorists understand the working OF
Tho engine and how the power is APP
piled to running the car Expe rience
indicates that tremendous percentage
os drivers have only a slight acquaint-
ance with the mechanism and the prin-
ciples underlying its action.
The engine generates power which
drives the automobile. This is done by
taking in gasoline. which is burned
and IN that process expands. creating
pressure. It is the function Of the en-
CINE mechanism to transmutc this
pressure into usable power The gas
cline usually is carried in tank
'ocated at the rear OF the car frame.
rom this tank 1t is drawn by suction
rom the intake manifold INTO a small
Isnk located near the engine whence
Il flows by gravity to the carburetor.
Raw gasoline burns very slowly and
IS not suitable for use in the auto
mobile engine, where comparatively
'ast burning is required. The func-
lion Of the carburetor is to mix the
gasoline with the proper proportion of
ak and to turn it into vapor to make
1t burn more rapidly. In addition to
mixing and vaporizing, the carburetor
3 htted with throttle valve with
which the amount OF mixture allowed
% enter the cylinder may be rcgu-
ated.
How Gas" Is Used
The gas is drawn from the carburetor
past the throttle and through the inlet
valve into the cylinder on the suction
or intake stroke. 1t is then compressed
and ignited by an electric spark II
expands and gives the power.
The action of the motor is that by
frawins down the piston vacuum
s created in the upper part Of the
cylinder. called the combustion cham
ocr. Al the right moment an inlet
awe opens and charge OF mixture
s sucked in. The valve closes and the
piston, rising. compresses the mixture.
Ut the highest point OF piston motion
:. spark is produced at the plug the
mixture is fired, expands. and forces
,he piston down with power. Through
he connecting rod the downward force
changed into rotary motion in the
process gives the power which drives
.hc car. The hywheel carries the
rank over the strokes which do not
foduce power
There are four strokes TO each
engine cycle. The first. taking in the
n.l;turc. is the suction stroke; the
ext. as the piston rises, is the COM
''ressior stroke. An explosion sends
ee piston down on the power stroke
bo
4 The exhaust strike The four
,rohes take two full }c'. v'.ous Of
&c crankshaft. On a fovr cvlirder
otor there IS always one power stroke
IA one of each Of the other strokes
- tho same time.
The explosion or mower stroke does
- come in regular sequence in the
.FAnders, that IS; they. do no. fire
ouWnes with larger number of
'rlinders The order varies. one firing
crdcr for an eight cylinder motor be
"g |. 4. D. ,, I, S. S. 3.
Il will be seen from the foregoing
hat It takes three things to make an
euginc go: proper mixture Of gaso-
ne and air. compression and ignition
At the right time. A proper mixture
rould nc considered 200 cubic feet Of
PROPER scavenglng more air usually s
Introduced In starting more gasoline
3 admitted 10 tho vaporizing chambc,
20 give rich. easily ignited mixture
IN running a lean miXture gives bette,
results
TIE compression also must he good
40 that there q decided reeis+anr,
~nen the motor - cranked over b.
and. The COMPRESSION heats the mix
when the sparh occurs IGNITION ia cas-,
10 insure good compression there mus
ne the proper relation between pistor
rlngs and cylinder and there must h
seal OF lubrlcating OIL in addition :
make the combustion chamber practi
eally gas tight. Valves mus, scat proy
erly, and cocks, 9askets and other open
ngs be free from Iea..z.
Not the least important "a the sDarl
This comes from a battery or magnet
r low vo tagc. stepped up to high vol1
age bv means of coil. 80 that IN
spark produced across the points Of tn
Mug is hot and possessed OF the reou
,ise kick. l. ls distributed 20 IN
cylinders by distributor or timing d,
vice, so that the spark comes at II
noint o. highest compression.
In starting me spark IS retarded
prevent bacA pressure OF motion. An
Then the engine ls running the sDay
advanced so tnat ignition Of II
/ mixture, started before the piston
'op q cylinder. viii be full as r.
piston starts 20 descend on the nowe
stroke. lnsuring full power from ~
conbustion
Muller Has Job
Another device whose Importance
a.ach moderated ~ TIE average drive
the mufHer through which n
7nned mixture - elected INTO the ono
ar. Il there were simply a plpe fro,
ne motor, without something 10 ,eade
~ sound. the burned gas. coming fro,
ne motor under pressure, would mai
great noisc, knocking grea. hole ,
n. air. The nufpcr permits The "a, :
cool and contract before issuine 10 ~
air and lets i. ou, slo+rl, and VII
rss vfhen1encc Gas. heated cxDand
rapidiy. Cooled, it. contracts rapid,
asu-slly a cooled gas would be c
.nallcr volume 'Ean that right fro,
he motor and would make less Of
hole IN the atmosphere. The d,Tel
nee IS easily illustrated II there be
clt-oat on the car