Evening star. [volume] (Washington, D.C.) 1854-1972, 1920-08-15
Answers to Last Weeks Questions.

| answers TO Last Weeks Questions.
l. A two-speed rear axle used
on an automobile is one having two
|two-ring gears and two bevel pinions
attached to the differential casing in
lstead of one set as is used with or
binary axles. With this axle two diff
lferent ratious of speed are obtained.
the drive being through one set of
lgears at time. These gears are en-
gagged or speeds changed by means of
sliding clutches operated by q shifting
lever from the drivers seat
| 2. The presence of sufficient uuan-
fifty of oil or water on the exterior of
a spark plug, so that it will make a
connection between the plug terminal
and the shoulder which screws into
the cylinder, will cause a plug to mis-
fire even though the points are clean
The oil or moisture, together with
dust and CRIME, collect on the porce-
lain or mica insulation, and if not
Icleaned occasionally will in time short
circuit the plug.
3. Attend to your tire valves and
their caps occasionally. The cap
tshould always be carried to cover the
valve, not only to keep out dust and
dirt, but to maintain an alright con-
nection. preventing tire from defat-
ing should something go wrong with
the valve inside. This cap, if tightly
the entire pressure Of air within a
tire, without a leak.
4. With the new forms of automo-
bile insurance regarding theft an
owner of a low or medium priced car
is obliged to use some approved form
of locking device at all times, other
wise he is penalized. Approved locks
are in various forms. There are steer
ing wheel locks, either holding the
wheel rigid or allowing it to turn
without engaging with the steering
gear; front wheel lock and devices
which do not allow the motor to start,
but which are not wholly successful
because the car under these condi-
lions may be towed away.
5. The simplest form of gearing in
a steering device for automobiles is
bevel or spur pinion gear at the
spur or bevel sector or rack with
at least twice the number of teeth of
the former. BY turning the steering
Wheel two or more complete revolu-
tions, the front wheels may be
brought from their furthest position
at one side to that of the opposite
SIDE; This form of steering gear is
used on many light and medium
weight cars, and although not ire
versible. it is easily operated
s: A denied rim which causes any
reformation to the side walls or bead
OF tire should be Strengthened, to
prevent inward strain from cutting or
weakening the fabric. If the. rim is
bent outward it may allow water or
sand to work in between the rim and
tire and possibly between the casing
and tube.
z. A four-cylinder engine magnetic
is driven at crankshaft speed. The
magnetic for six-cylinder motor is
turned one and one-half times as fast
as the crankShaft reyolyes
.. The amount of heat lost by a
water-cooled engine through its cool
ing system varies with the make of
the car. 1t ranges from 40 to SIS de-
grees of the heat generated in the
combustion chambers.
3. Valuation of auto repair parts
manufactured during 1919 is $117,0OO,-
900. This valuation is given to pas
senger car parts.
10. Defects of a vibrator coil which
would give an unsteady spark or pos
sibly no spark are contact points OF
the vibrator becoming burned or pit
ted, broken or burned wires and loose
terminals. The vibrator will stick
at high speed If its points are pitted,
and will give poor spark at either
low or high speed if the points are
burned.
This Weeks Questions.
l. With an idle engine and dis
tributer exactly at firing points. would
it be possible to turn the ignition
switch on and get continuous spark
at the sparkplug?
2. What is the proper gap to leave
when setting valves of a motor?
3. Is an allowance made on auto
mobile insurance for theft if spare
tires are locked continuously by a de-
vice approved by underwriters?
4. How should valve stem be re-
placed in an inner tube?
5. Does car vibrate more when it
is travelling in second or low speed
than it does on high speed?
6. How many motor cars and trucks