Evening star. [volume] (Washington, D.C.) 1854-1972, 1938-11-06
Hints That Increase
Motoring PubIit's
Enjoyment
neine Best When
Exhaust Offers
Little Resistance

6xnouSt OTteIS
Little Resistance
The world is waiting for q day
when science discovers gas that
Is safe for motorists to step on.
If had stopped the driver Of
the car ahead of me on hill the
other day to tell her why her car
did not perform normally she never
would have believed me. Yet the
fact remained that the lack Of
power evidenced by the poor per-
Torrance of her car was directly
due to a pinched exhaust pipe.
There was scarcely space for the
exhause gases to be expelled, so
badly was the pipe damaged. From
where I observed the situation 1t
looked as If the car had been backed
into a rock.
For normal performance an engine
must have as little resistance as
possible in its exhaust system. An
engine can be stopped by plugging
up the tail pipe. Best evidence of
the recognition given to the engines
need in this regard Is the modern
mufner which allows the gases to
pass straight through, muffling be-
ing accomplished by giving the gases
opportunity to expand radially into
dead ends as they pass through the
center chamber of the mufler.
Fitments Step Out.
1t L. perhaps natural that with
the accessory business assuming
such impressive proportions there
should be marked trend toward
improvements on familiar as we'll as
new gadgets. Perfect illustration is
found in the very latest rubber
bladed fan which runs up to 2,700
revolutions per minute without
vibration just because its sponsors
thought Of putting metal weights
into the blades near where they
are nodded into the hub. Most
rubber bladed fans start shaking
when they get up around 2,400
revolutions per minute.
Marked improvements in hot
water heating this year are the re-
suit Of making better use of the fact
that heater core has hot spot on
which the fan should concentrate.
Welcome, too, Is the better plating
of useful equipment for the cars
Identification and safety. The best
radiator grille guard now on the
market is given such q generous
coating of chromium that it will
not rust, thus serving its owner
over far longer period than guards
which rust out and become useless.
Mechanic Joe Speaking:
TITS all right to know how to
make certain handy tests of the
engine, but usually it's more I'M
portant to know when to make
them. was reminded of this when
q customer told me that even
though he had gone to the trouble
OF short circuiting the spark plugs
he had been unable to locate the
cause Of a knock in the engine.
"Of course, this test is only for
determining the approximate loca-
ton Of such knocks as result from
loose connecting rod bearings, loose
plstons and worn piston pins. It
can also be used for locating main
bearing knocks, but usually this is
not successful in the hands of the
average owner. For locating causes
OF minor engine noises the test is
OF no value. In the group of minor
noises include excessive carbon, fuel
defamation, excessively advanced
ignition, lean mixture knocks and
worn tappets."
Good Tests to Try.
There are two tests for dragging
clutch, and every driver should
apply them as often as he can think
OF them. The first is to note If the
gears grind when shifting into low
gear after pressing the clutch pedal
to the floor. The other is to coast
with the clutch disengaged, noting
the action of the ammeter while
doing so. If the ammeter does not
immediately indicate discharge
tmaking sure that the throttle is
closed to the idling position) then
the clutch plates drag.
Makes Shifting Easier.
IT you have not switched to winter
LUBRICANT Tor the transmission, and
are troubled by having the gears
shift hard, temporary solution to
your problem is to increase the
engines idling speed. This can be
done by pulling out the hand con-
srol OF the throttle just enough to
speed up the clutch gear of the
transmission. When the engine is
equipped with fast-idling carbure-
tor this will be taken care of auto
matically.
Tread Out of Balance.
It's all right to have plenty of
tread on the tires of your car, but
bear in mind that tire designers
are faced with the problem of effect
ing a proper balance between tire
tread and tire carcass. They find
that If the treads are too heavy for
the tire there will be excessive
rumbling as the car travels over the
road. This noise, Objectionable in