WATCH YOUR BRAKES
Look well to the condition of the brakes on your car before starting on
a trip. See that they are in good shape even if you do not have time to
look over the engine. The brakes are more important than the engine. It
needs an engine in at least fair condition to get anywhere, but if you
do not have brakes you may get too far—too eternally far.
Manufacturers of cars have recognized the importance of the brake
appliances and have given considerable attention to the improvement of
the brake, designing more efficient operating mechanism, increasing the
size of the braking surface and improving the quality of the friction
materials, and also in protecting the brakes from excessive wear due to
grit and dragging of bands when not in use.
The brakes, moreover, on the average car of modern design, are
sufficient for all general use, if used intelligently and if they are
given a moderate amount of care. But like most other parts of cars,
some owners give them no attention whatever, and consequently there is
frequent failure and often it is a matter of life and death when the
brakes refuse to work properly.
First of all, owners should understand that there are two sets of
brakes on the car, which operate independently of each other, and
each brake should be capable of holding the car at a standstill on
practically any grade, or, as the chauffeur usually puts it, “sliding
the wheels.”
A recent experience with a Ford car illustrates the need of the owner
thoroughly understanding his braking system. This was a case of a
new car where the owner had not yet become very familiar with the
mechanism. He came to a very long and fairly steep hill. He released
the clutch and applied the brake as he had been taught, and got about
two-thirds of the way down the hill when the brake lining burned out
and the brake no longer held the car. Then, because he forgot what he
ought to do (or else did not know), the owner lost his head and thought
he was going to smash, and of course did. The car ran into the ditch
and upset, bent the front axle, broke the mud guards and top bows, and
mixed things up generally, but fortunately no one was hurt.
This was all unnecessary, for on this particular car he had three other
means of braking. He could have pushed the pedal which engages the
low-speed gear and kept the car at low enough speed to negotiate the
hill in safety. Or, he could have pushed the reverse pedal, which on
this particular car would have acted as a very efficient brake. And,
also, he might have applied the emergency brake, as on any other car.
As every car is equipped with two distinct sets of brakes, drivers
should learn to use first one and then the other on long grades, and
this may be helped out considerably by using the motor as a brake—that
is, by cutting off the ignition and allowing the machine to push the
engine under compression, and even more by engaging a lower gear before
cutting off the ignition, so that there is a greater leverage obtained
to retard the car. Likewise, long grades should be descended at a
comparatively slow speed in cases where the brake is at all necessary,
because the higher speed develops more heat and the brake lining is
more likely to burn out.
Of course the brake lining has been improved so that it does not
actually burn out very readily, but under extreme conditions it will
become charred and lose its frictional qualities.
Perhaps one of the greatest causes of brake failure is oil. Now the oil
which gets on the brakes usually works through the rear-axle housing
from the differential gear. The owner may be a little too enthusiastic
about lubrication and may put too much oil in the differential and it
travels along the inside of the axle tube. The wheels are so placed
on the axle that this oil can get out only by working over the wheel
bearing and into the brake drum. It will often be noticed that the oil
collects mostly on the right-hand brake. This is because the crown of
the road, and perhaps the ditch alongside of the road which is used
in passing other cars, tilts the car so that the right-hand wheel is
lower than that on the left-hand side. Even where too much lubricant is
not used, it seems that some cars have a tendency to leak oil from the
right-hand wheel housing.
Usually this trouble may be overcome by taking a long, thin strip of
hard felt of the proper thickness to fill the space between the axle
shaft and the axle housing, and winding around the shaft in helical
form, so that the action, when the shaft is turned, is to force the oil
back toward the differential. Of course, if the felt is not wound in
the right way it would have the opposite tendency and draw the oil out
into the wheel bearing.
For this reason the felt should be wound, starting from the wheel end,
in a direction opposite to the forward motion of the wheel, covering
the axle for a distance of six or eight inches. The felt should be
fastened to the shaft with shellac and bound in three or four places
with cord.
While oil on the brake bands is not desirable, oil on all of the
bearing points of the brake mechanism is highly desirable. Some time,
when driving in a city, take notice of the number of times the brake
is applied. Then stop to think how each action is taking place in the
brake mechanism. This ought to bring one to realize the necessity of
lubricating the bearing parts. These need more frequent oiling because
they are placed where they pick up more than the usual amount of dust
and grit. If the lubrication of these parts is neglected they are
likely to wear unduly and become so weakened that a sudden emergent
strain would mean a break; and this might happen at a time when failure
means death to the occupants of the car.
Brakes of modern design are so arranged that the bands clear the drum
entirely when they are disengaged. This is done by means of springs and
other devices placed around the drum at different points. These springs
should be inspected occasionally to make sure that they have not
become broken or otherwise fail in the performance of their functions.
Another cause of brake failure is due to the lining wearing thin and
allowing the copper rivets, with which it is fastened to the band, to
come in contact with the brake drum. This in time scores grooves in
the drum and greatly reduces the braking effect. It is not economy,
therefore, to wear the brake linings entirely through. When they become
thin the linings should be inspected, and be replaced as soon as the
rivets begin to show wear.
The usual practice is to have four brakes, one on each rear wheel
operated by the service-brake pedal and one on each rear wheel operated
by the emergency lever. The emergency brake is designed more for
holding the car at standstill after it has been stopped, but may be
used alternately with the service brake on long grades. The service
brake should be kept in such condition that it will bring the car to a
stop within a reasonable distance at any car speed, and it should be
understood by the driver that the emergency brake is not intended to be
used to help out the service brake which holds poorly when a quick stop
is desired.
[Illustration: REAR WHEEL AND BRAKE DRUM REMOVED, SHOWING EXTERNAL AND
INTERNAL BRAKE BANDS AND MECHANISM]
Many manufacturers term the second brake the hand brake, rather than
the emergency brake, to discourage the idea that it is to be used to
help out when an extra quick stop is desired. Too many owners go upon
the assumption that one good brake is all that is necessary, and allow
one to get into such condition as to be useless when the other fails
unexpectedly, or when it is desirable to use the two sets alternately.
As to the adjustment of brakes, it is very important, in order to get
the best braking effect—and to save wear on the tires as well—to have
both brakes of a set give about the same friction. There are two places
where adjustments may be made, one at each brake and one on the brake
linkage, usually on each side, but possibly on the single rod connected
to the pedal. By means of these two adjustments it is possible to have
the bands clear the drums when the brakes are released and at the same
time have each brake start to take hold at the same time and with equal
force. The equalizing bar helps out in small variations, but cannot be
expected to take care of the entire adjustment.
When one considers the multitude of accidents because the “brake
gave way” and of the risk taken by others who fail to care for this
important bit of mechanism, it would surely suggest to the careful man
that he study the construction of the brake upon which he depends on a
down grade and that he give it enough attention to know that it is in
working order. If he does not value his own neck enough for that, he
should at least have a care for those who share the danger.