Evening star., 1922-08-20
THE OWNER-DRIvER'S
COLUMN.

There are a great many cars on the
road. the headlamps of which are not
properly adjusted. Some lamps light
the whole countryside. but give very
poor driving light Others are poorly
focused and are bent up, so that the
light is thrown too high. Such lights
are Of little use. to the driver. and are
sure to glare into the eyes Of drivers
meeting them.
Adjusting Of headlamps must be done
at night Face the car toward the wall
of some building at a distance OF forty
feet from 1t. If properly focused there
will be two circles Of light three feet
in diameter. the edges Of which Will
just touch each other. If the ground
Is level, the lower edges Of the circles
half above the ground. II the size OF
the circles is not right, adjust by NOV
ing the bulb nearer or farther away
from the reflector until correct.
There are different methods of chang.
ing the position Of the bulb in different
makes of lamps. There IS usually "a q
which the adjustment can be made.
though on some 1t is accomplished by
screwing the bulb into or out OF its
socket
Lamp brackets sometimes become
bent up or down. II the test SHOWS
the circles of light too high. a slight
bending will put them into the proper
position.
Air Pressure In Tires.
When driving along the road we fire.
quently get considerable entertainment
out Of study of the car immediately
ahead Of US. With other things we
are always on the lookout for waboiy
rear wheels. unequally adjusted brakes
the tires Of a chauffeur driven car un-
derinflated. He knows the value OF
proper imitation. and keeps his tires
just right. The owner-driven cars. how
ever. show high percentage OF UNDER
imitation.
Underinflation means a continuous
bending OF the tire walls as 1t fiattens
to the road. A piece Of wire cannot be
broken at the first bending. but repeat
this bending few times and the wire
will break quite easily. The same thing
Is true. to a certain extent, OF the tire
wall which is subject to a continual
bending and Strengthening process on
the road. The bending the tire wall
causes a breaking loose Of the rubber
from the fabric: causes The fabric IT.
self to break and causes the tire to neat
excessively Just as the wire heats when
II Is Dent III tne naHQ meat tpuS 81
Grated causes a host Of troubles OF Its
own.
Some tire makers stamp the pressure
their tires should carry on the tire, In
which case their advice Is readily
followed. Where this is not done.
the following rule holds good-Twen-
ty pounds of pressure to every inch
Of a tires diameter is the correct
pressure. Thus a thre -and-a half
inch tire should be inflated to seven
ty pounds, four-inch tire to eighty
pounds. and so on.
No motorist should be without a
tire gauge. What is more. it should
from an air station. care is necessary
not to overinflate a tire. The pres
sure at these stations is frequently
twice as great as Is necessary for the
average tire.
Cleaning the Radiator.
A friend of the writer's recently
purchased a 1917 model used car. The
car had always had good care and
was in good running order. but the
overheated. Tightening the fan belt
made no difference. The carburetoi
| mixture was cut down to the limit
the valves and spark were timed per-
fectly. SO the only thing left to cause
overheating was the cooling system
itself. We drained the radiator and
an enormous amount of rust came
with the water. We then started the
engine. opened the petcock under the
radiator and ran the water out. Al
| the same time we sent stream OF
clean water into the radiator from q
hose 1t required half an hour Of this
| treatment before the water from the
drain cock was reasonably clean. The
amount of rust on the ground was evi.
dence as to the cause Of the overhead
ing.
To make the cleanout complete. the
| system was filled with a hydrochloric-
acid solution. a pint of acid to five
gallons of water. This was left In
| for a twenty-mile drive. then drained
and another ten minutes of riLsins
| out with the engine running and a
stream from the hose running into