Evening star. [volume] (Washington, D.C.) 1854-1972, 1920-09-12

, WiSn 10 tfoVei. 1no Ao1 " Aau AIV
backward motions are similar to
those employed in a garage when II
lis necessary to move q car short
idistance to the left or right OF wherc
ut stands. and the success OF the oper-
alton depends on proper handling OF
the steering wheel.
3. A gasoline engine must first be
cranked to produce continuous orivin8
power. because gas must be draWn
into the combustion CHAMBERS OF
each cylinder, compressed by the
pistons and ignited by sparks at the
plugs before it will expand and give
driving power at the pistons. When
lcranking begins. and when the en-
gin begins operating under It's own
power the action of drawing In gas,
COMPRISING it. igniting 1t and forcing
out the burned gases continues auto
matically.
4. To insure low resistance to dow
of electricity through Joined wires or
a wire permanently Attached TO ter
minal always solder such connections
vent corrosion from adding resist
ance to the current, and will greatly
strengthen the connection.
5. Commentators of starting motors
and generators should be cleaned once
or twice season to insure best re-
suits. Loosen up the dirt or gum on
the surface Of the commutator with
kerosene applied carefully with cloth.
Lift the brushes while this Is done,
so that none of tho liquid will touch
them. When the gummed surface Is
loosened wipe commutator with clean
cloth. To maintain the space between
segments of the commutator groove
out the mica insulation between seg-
ments. Start the groove first with a
three-cornered file, then finish under
mica should be cut a thirty-second Of
an inch below the surface OF the COM
mutator. To smooth the commutator
use very fine sandpaper. Lift the
brushes and wrap the sandpaper around
commutator So that both ends Of paper
until bright Polish with cheesecloth.
s. Sparkplug electrodes, mainly the
center point. are made of nickel alloy.
Most other metals would expand under
great heat in the cylinder head and
crack the porcelain insulation OF the
plug.
Z. To adjust a carburetor for high
speed work cut down the mixture un-
til it is SO lean that the motor will miss
on low speed when running idle. Then.
adding just little more gas to the
mixture, test the adjustment on high
speeds, quick acceleration and hill
climbing. A weaker mixture can be
used for speed than for heavy or slow
work.
8. The more technically correct
name for the automobile power plant
is the word engine, although it is pop
uIarly called motor.
9. Cylinder lap in engine operation
is name applied to the distance two
pistons travel together on power stroke
1t means the tapping of power strokes
or explosions. In a four-cylinder en-
CINE there is an explosion to every
half revolution of the crankshaft. one
power stroke beginning as another fin
ishes: therefore there is no tapping of
strokes. In the six-cylinder engine the
second power stroke begins before the
first ends, a distance of fourteen de,
grees on the fywheel; therefore there
is fourteen degrees lap. In the eight
there is forty-four degree lap and in
the twelve three cylinders working to-
gether on power stroke form a lap Of
fourteen degrees.
10. A good tire preservative Il a
liquid rubber paint made from I'M
vulcanized rubber. Applied with a
brush. it will preserve the tires by
filling small cuts, preventing de-
terioration and identifying them
This Weeks Questions.
l. How can a magnetic armature be
tested?
q Why is the fywheel Of four
cylinder engine required to do more
work in the motors operation and
is usually heavier than that Of en-
gines which have six or moro cylin-
ders?
3. How many cam shafts does the
eight and twelve cylinder v typo en-
CINE have? How many cams are re-
quired to a shaft?
4. What is the condenser Of an in
duction coil or magnetic armature:
5. What is good rust preventive
to apply to a motor exterior?
6. Near which valve should the,
sparkplug be located in the cylinder?
Why issit placed in this direction?
Z. What is the automatic spark con-
troll? How is 1t operated?
s. How many feet per minute
would piston of an engine travel
which is operating at the rate OF 500
revolutions per minute and has .
stroke Of four inches? How is this
figured?
3. What is a way to remove q tight
fitting stud without damaging the
threads?
10. What is a good way to nnd a
leak in a radiator?
Copyright. 1890 Thompson Feature Service