Evening star., 1934-05-20
BY FREDERICK C. RUSSELL.

JUDGING by the appearance OF
some peoples bumpers many driv-
ers believe in answering a fool accord
ing to his folly.
You may be puzzled because the en-
gine seems to collect too much carbon
soon after having carbon removed.
Perhaps you have even suspected that
the mechanics did not do the job
properly. I'll admit it seems all up
side down to state that clean engine,
if well worn, will collect carbon faster
than one that is already carbonized,
but I can explain it by saying that the
carbon in a motor acts as a seal to
help prevent oil from sucking up
around the piston3. The situation
isn't, however, hopeless. If an en-
gine collects cabon too rapidly you
can have new rings installed.
Because so many Of the cars today
carry carburetors with fixed jets there
is not SO much opportunity for road
side mechanics to tamper with this
important unit This is both bless
ing and an evil, because too often
when a tinkerer finds he cannot
change the adjustment any other way
he will take out one OF the jets and
enlarge it. This is comparable to tell
ing the factory engineers that they did
not know their business.
Let's avoid this. There are legiti-
mate cases where jet sizes should be
changed. but 1 have received enough
letters recently to suggest the wisdom
of not sanctioning promiscuous jet en-
largement.
In one of the new car instruction
books it is recommended that tires be
inflated to % pounds when cold, 25
pounds when hot. For instance, If
you are just rolling out of the garage
the preSsures should be given cold tire
setting. If you stop at filling sta
tion while on trip give them the hot
tire pressure. With the new spring
suspension, moreover, it is particularly
important that the tires be exactly
right.
Many woman who doesn't favor
free wheeling actually indulges in a
mild form through her habit of bear
ing nervouSly on the clutch pedal
when going downhill especially when
trying to make up her mind whether
or not to shift into a lower gear. In
cidentally, a driver can always tell
whether or not the clutch is engaged
or disengaged by watching the am
meter pointer. If this indicator shows
discharge when pressing the pedal the
oil, +1I, i ha; eli ;,,+0
ment.
Women are naturally skeptical when
obliged to have the car attended to in
strange town where they are not
familiar with the service people. But
no owner of a modern car need be in
doubt as to whether the oil in the
motor has been changed. The bayo-
net type Of oil gauge now so generally
used not only tells you how much oil
is in the engine but also gives you a
broad hint as to the quality of the
oil Before you have the oil changed
pull out the bayonet and take look
at the oil that clings to it. Smell it
to note how much gasoline it con-
tains Then when the oil has been
changed take another look, making
sure you have wiped the bayonet clean.
The new oil should be clean and free
from smell of gas.
I like the way one of the automo-
bile companies explains how an auto
mobile engine converts cc5 into power,
A simple cannon is used to Illustrate
the idea Before firing gunpowder it is
necessary to ram the barrel of the gun
"a process that compares with COM
pessing the gas in a cylinder The
harder the powder is rammed the
more power it will deliver when fired.