Evening star., 1921-08-28
Answer. to Last Week. Questions.

Answers to Last Weeks Questions.
lit isn't hard to imagine the
nervous tension which would be Gre
ated by occupants Of car staiieo
on a railroad crossing, particularly
If q train was in sight. This situation
calls for rapid calculation and action
and not Mysteries, as is the ruIe IN
the majority of cases. Many dfs-
asters at railroad crossings wnich
could have been avoided have, never
theless, occurred merely because the
drivers Of the cars In question lost
control Of them. For instance, Al
most every car which stalls can pc
started within very rev sec9nt, h,,
because the engine rs VA waTT" ,'H and
the fuel mixture is at a good poins nj
of yaporization. All that would pc
required is to shift the gears 70
neutral and step on the staltlm1 inw
low gear and clutch and be on. but
the nervous driver instead OF using
this procedure forgets to disengagee
his gears. switches off his ignition' y y
is in the of position. and then tries
to start the engine. II he Is fortu-
nate to start the engine, he prooaOly
stalls 1t again. while trying 70 ,,,Eeoh ESe
pedal In too quickly or not opening
the throttle enough to take the car
load when clutch is engaged. Ai!es
the second stop he is more rattleo
despair. leaving the car upon the
tracks. The thing to do Is endeavGr
to start, II the starter Will not WORK
try the hand crank. II there Is nGs
enough time to do the the iatter, ;t oypSie. pSHi
the car Off the tracks, II moNaoAe'
and If mot flag the train.
2-To stop a car when the brakes re-
fuse to hold, there Is only one procedure
switch of ignition. engage lower gea1s
and engage the clutch. using the engine
as a brake. Play safe by inspecting the
brakes regularly and testing them AT the
beginning Of every trip. ,
3.-The spark should be advanced
when engine speed Is increased 70 9aI!'
maximum power from each explosion
with the minimum Of fuel. Retarded
spark at high engine speeds also causes
carbon deposit In cylinders. consump-
tion Of more fuel and In extreme cases
overheating.
GEAR and clutch and be on But
ion of the valves or by opening petc0Sks
OF removing spark plugs from tue cyln ~
ders. Using the valve position metn0o.
start at end OF exhaust stroKe IKE ~n1n 1indsr i,.r
and when the exhaust valve IS CLOS,
ing. Reyolve the engine further anu
the exhaust valve will close ana I'M
mediately the inlet valve Will start
TO open. The piston is now starring
down on suction or intake stfoke'
ton is on compression stroke. BY
opening petcocks. one at time, VIII
give forth a kissing noise when the
various pistons come up on COM
preston strokes. as also VIII happen
If spark plugs are removed
$hn
of shifting or changing in position
Of the front wheels when the car Is
in motion. and changing the course
Of the car frequently on wavy or
rough roads, even when the steering
wheel is not moved is that Of wear In
steering gear or loose parts or con-
nections causing play. If this play Is
present the front wheels will shift
from side to side to the extent OF the
lost motion in the steering controls
and make the car unpleasant 20 drive.
incidentally loose or otherwise poor
steering control has been the direct
cause Of accidents to the car.
G. 4 car cannot run without a diff
ferential, because it would be impoS-
sible to turn a corner without dam
aging tires and straining the whole
drive system. The reason is that on
turning the rear wheel on the inside
of the turn must revolve slower than
the other wheel, having less ground
to cover. This difference in revolu-
tions is taken care of by the differ-
entail gears.
Z. 4 small four-cylinder engine is
more apt to labor and knock on
heavy pulls, such as hill climbing,
than ;sle larger engine of six. eight or
more cylinders; beeausexin the-four-
cylinder engine each piston does not
travel the full length of a stroke
under power-a distance OF about AZ
degrees in revolution being covered
under momentum of the f1ywheel. In
engines of more cylinders there Is a
lap of power strokes, one piston still
being under power of an explosion
when an explosion occurs in another
cylinder. Thus on heavy pulls the
small four, relying on momentum OF
the fywheel only between power
strokes works harder than the larger
engine.
8. Common clutch troubles can be
classified somewhat as follows: Slip
ping clutch. caused by worn or dry