Evening star. [volume] (Washington, D.C.) 1854-1972, 1920-12-05
Answers to Last weeks Questions.

Answers to Last Weeks Questions.
1. In a snigle-wire electric system
either terminal may be grounded, as
the flow of electricity will occur just
the same. AS a rule the positive IS
the grounded terminal.
2. You can soon tell if the carbure-
tor mixture is correct by opening the
petcocks at the tops of the cylinders
elf the engine has them) one at a
time and noting the color ofsthe flame
which energies from the cylinder
while the engine is running. If the
flame is faint blue the mixture is
correct. II it is red. too much gaso-
Inns is being consumed, and IL the
flame is yellow the mixture is too
lean.
3. The greatest amount of efficiency
from an engine while in operation is
obtained when the cooling water has
a temperature of from 10 to 80 de-
grees. If of lower temperature the
gasoline vapor has a tendency to con-
dense. and causes poor engine opera
ton and carbon deposit. If of high
er temperature the water will evap-
crate quickly and boil.
4. To aid starting a cold engine in
winter, before stopping the engine
accelerate it's speed by opening the
throttle. Then switch off the igni-
Tcs. and quantity of the carburetor
MATURE Will DS uTdW lntO the Cy
ders. where it will remain until the
engine is again started.
D. The oil pressure gauge on the
dash sometimes registers high oil
pressure at slow engine speeds when
the engine is f1rs.s tarted. This is due
10 the CONCEALED oil in the line leading
to the gauge and also in other parts of
the lubricating system. If this condi-
tion. exists only as long as the engine
IS cold there is nothing at fault, but if
high pressure is continually regis
tered. even after the engine is warm.
the fault lies in clogged oil lines or
the gauge is out of adjustment.
s. Experience has taught many driv-
ers that the slow intermittent appl-
cation of brakes will give the best
results in stopping the car on slip
perry pavement. Steady application,
especially when too much pressure is
eXerted on the brake pedal, may cause
locking of the rear wheels and skid
ding, and has caused many an acct
dent.
tor mixture is too much air and not
enough gasoline Ca condition seldom
encountered in the average carr.
sThe trouble may be due to fault
of the carburetor itself, such as gaso-
line or spray passages blocked, throt-
tie valve out of adjustment. or SPRAY
nozzle ~ciogged, or there may be a
blockade or a break in the gasoline
line from supply tank to carburetor.
The outlet at the tank may be partly
clogged, there may be water in the
gasoline, the fuel may be stale from
lengthy standing unused, or of a poor
grade. All of these defects may cause
lean mixture, and in addition there
is the common trouble of lack Of heat
to properly vaporize the gasoline. re-
Sulting in poor mixture in winter.
s. The usual cause of an old engine
overheating more easily than a new
model is the combination of poor COM
preston. which leads to excessive car
bon deposit and pre-ignition, and the
lime and rust which gathers within
the water jacket surrounding the
cylinders and in the radiator, pre-
venting proper cooling
9. The radiator shutter or cevef is
not absolutely necessary to a car the
cooling system of which contains an
anti-freezing solution. but some means
of shutting out the cold air from
radiator and engine is advisable for
quicker heating of the engine, when
cold. 1T will also insure better run
ming of the motor. and is. a precaution
when the car stands idle, exposed to
the weather.
10. One test to ascertain the quality