The Washington herald., 1916-05-21

should be well but not over lubri-
Gated. The pistons should be properly
should be given enough clear
ance so that they cannot blind when
they become hot, and should be as
light as possible consistent with proper
strength. The rings should be closely
but freely fitted and well Tapped in.
They should be of such design as to
produce a uniform pressure against
cylinder wall at all points in their
circumference, and this pressure need
not be very great II the ring Is well
fitted. Concentric rings properly peen-
ed on their interal surface will prob
ably satisfy these conditions most
nearly. The eccentric type of ring
may create too high a pressure at
some points in it's circumference and
for this reason wears the cylinder more
rapidly and produces undue friction.
Bearing. Must BE oiled.
All bearings in the motor should.
OF course. be well fabricated and prop
erly aligned. The accessories driven
by the motor should be kept in proper
alignment and we'll fabricated.
The clutch should be carefully ad-
justed for proper alignment with the
motor and its bearings supplied with
oil or grease at frequent intervals.
Much the same rule applies to the
transmission and differential gearing.
Proper alignment of bearings and
gears is, of course, essential. One point
frequently overlooked, however, is
tho selection of a proper grade of
grease or other lubricant. This should
be as light, that is, as free flowing as
1t is possible to use and keep in place
in the parts to be fabricated. Grease
never should be used where oil can
be kept in the container provided, and
when used should be as soft as posi-
BILE.
Good fabrication and proper alignment
of parts are two prime factors in de-
creasing frictional losses. but they are
by no means the only important factors.
Unfortunately the largest frictional loss
in the whole car, save perhaps that In
the motor itself cannot be reduced by
fabrication, and is possibly for this very
reason, frequently overlooked. We refer
to the Internal friction of the tires. In a
car of average weight this loss may be
over one and one-half horsepower per
tire at speeds OF about fifty miles per
hour. 1t varies in almost direct proper
ton to the speed, and increases rapidly
as the air pressure in the tire decreases.
Have you ever stopped to figure why four
or more men must often use all their
strength to push a heavy car on a level
floor? Do you know that one man can
easily move the same car II the tires are
removed and the car allowed to rest on
the steel rims? Consider this fact and
you will at once appreciate how large a
factor tire losses are. Now how may
they be reduced?
First Of all by keeping the tires proper
ly inflated. This is good for the tires
from the standpoint of durability as well
as from that of reducing friCtional losses
Keeping the tires well inflated is, in
fact. the only means the user can employ
with a view of minimizing frictional
losses in a given set of tires.
Friction Loss Factor.
One other loss due to friction should
not be forgotten since II is often a very
large factor. This is the loss due to drag
ging brakes and, fortunately, one tina
may be entirely remedied by careful ad
justment. The retarding influence o.
badly dragging brakes is certain to be
noticed by an experienced driver. 1t no
only holds back the car but causes eN
cessive wear and heating OF the brake lin
ing as well as the brake drum, and i
unequal on both sides of the car will
cause more rapid wearing of one Of tht
rear tires. See that the brakes are ad
Justed so free as to allow the rear wheel!
to spin easily when lacked up and keel
track of them to see that they do not be
come hot in straightaway running wher
brakes are not used. II you travel tht
same grades frequently stop the car a.
the top OF long grade occasionally, star
it slowly and then declutch and allow the
car to coast until 1t comes to a standstil
without applying the brakes. This viii
give a rough measurement Of frictiona
losses and If repeated frequently undel
the same road and wind conditions will
give the user a check upon the condition
Of his car with respect to frictional losses
losses.
II one does not object to the inconven
ience quite a saving in fuel may be af
Ience quite a saving in fuel may be ef,