SPRING CARE TESTS
Information recently gathered from observation and interviews shows
that the average owner who operates and cares for his car, invariably
overlooks the springs and their connections while giving the car the
bi-monthly or monthly tightening-up and greasing, while the balance of
the car usually receives the required attention.
This fact seems to be due mostly to an oversight, for the springs are
usually inspected while the car is motionless and at this time they
do not show defects readily, and have the appearance of being rigid,
inactive, and compact.
=Weekly Spring Care.=--Weekly spring care should consist of filling
the grease cups (with a medium hard oil cup grease) and turning them
down until the grease makes its appearance at the outer edge of the
spring eye. This, under ordinary driving conditions, will be sufficient
lubrication for one week. But in cases where the car receives more than
ordinary use the grease cups should be given one-half turn every second
day. The shackle connections should then be wiped dry to prevent dust
and grit clinging and working into the bearing, which causes much wear
on even a sufficiently lubricated bearing surface.
=Bi-monthly Spring Care.=--Special attention should be given at this
time to the U-shaped clips which connect the spring to the axle. A
loose clip means a broken spring at the first severe jolt, caused by
the rebound taking place between the clips. Therefore, tightly adjusted
clips will prevent action from taking place at the point between the
clips where the leaves are bolted together and will entirely eliminate
spring breakage. Tighten up the nut on the leave guide clip bolt to
prevent rattling. The shackles should be inspected for side play. To
determine whether there is side play, jack up the frame until the
weight is off the spring, then grasp it near the shackle and shake with
an in and out motion. If there is play a rattle thump will be heard.
To take out play, remove cotter pin and turn up castillated nut snugly
on the shackle pin. If the nut cannot be turned up a full notch, place
a thin washer over the end of the pin. The nut, however, should not be
turned up too tight as a certain amount of action is necessary.
=Lubrication of the Spring Leaves.=--Lubrication of the spring leaves
should take place once every month. This point must be kept in mind
and adhered to, as a spring cannot produce the marked degree of action
necessary for smooth and easy riding, when the sliding surface is dry
and rusty. The leaves slide on each other when the spring opens and
closes, and if the sliding surface is not well lubricated the movement
will be greatly checked by the dry friction; these dry surfaces also
gather dampness which soon forms into dry-rust, which, in time entirely
retards action and results in a very hard riding car.
It is not necessary to disassemble the spring at the monthly greasing
period, unless the spring has been neglected and rust has formed on the
sliding surfaces. In this case the sliding surface of each blade must
be cleaned with a piece of sand or emery paper.
When the springs receive regular attention, it is only necessary to
jack up the frame until the wheels and axles are suspended, the weight
of which will usually open the leaves sufficiently to insert a film
of graphite grease with a thin case knife. In some cases where the
leaves are highly curved, it may be found necessary to drive a small
screwdriver in between them. However, great care should be exercised
in doing this, as the blades are highly tempered and spring out of
position very easily.
=Wrapping Springs.=--Car owners in some parts of the country grease
their springs and wrap them with heavy cord or adhesive tape. While
this serves to keep the grease in and the dust and dirt out, it also
binds the leaves and prevents free action. If the car is to be driven
for any length of time on sandy or muddy roads, wrapping may be found
very beneficial. But use only a water-proof material (heavy oil paper
or canvas) to wrap with. Cut the material into one and one-fourth
inch strips, and wrap from the center toward the outer end to prevent
binding.
The following shows the results of a spring care test conducted by the
writer. The cars were chosen at random and only those accepted which
had seen six months or more service.
Eighteen owners were interviewed. Six of this number gave their springs
a thorough greasing and tightening up every two weeks, and not one
of this group made a complaint of any nature regarding breakage,
stiffness, or noise.
Five of the remaining twelve, gave their springs occasional attention.
Their reports were not entirely unsatisfactory, but had a tendency
toward such troubles as rattles, squeaks, and stiffness in action.
The remaining seven did not give their springs any attention whatever,
and all made unsatisfactory reports ranging from broken leaves, to side
play, jingles, squeaks and hard riding.
Therefore the results of careful and regular attention may readily be
seen by the reports of the first six owners. All nuts and connections
were tightened, and the sliding surfaces of the leaves greased on an
average of once every two weeks. The springs gave satisfactory results,
and the cars retained that easy, soft, springy action, so noticeable in
a new car.
The reports of the five who gave their springs occasional attention
would probably have been the same as the first six, had they given the
proper attention more frequently. But they usually waited until the
trouble became annoying, which caused wear on the spring eye, shackle
strap, and pin, on each occurrence making a good adjustment impossible.
The stiffness in action and squeaks were caused by dry fractional
surfaces between the leaves which prevented free action.
=Types.=--There are five standard types of springs, and two or
three types of special design. The riding qualities of all types of
springs depend on their length and resiliency, which is taken into
consideration by the engineer and designer. Consequently there is not
much choice between the different types.
[Illustration: Fig. 128. ¹⁄₂-Elliptical Front Spring]
Fig. 128 shows the semi-elliptical type of spring used principally for
front suspension. The front end of this spring is bolted rigidly to the
downward end slope of the frame while the rear end carries a movable
shackle arrangement.
[Illustration: Fig. 129. Full-Elliptic Spring]
Fig. 129 shows the full elliptical type of spring which may be used
for either front or rear suspension. The ends may be fastened together
solidly with a yoke and eye arrangement, or shackled as shown in the
above cut.
Fig. 130 shows a spring of the three-quarters elliptical type used in
rear suspension only. This type of spring carries a shackle arrangement
at the front and rear end which allows backward and forward motion to
take place very freely, consequently it is very necessary to use a very
substantial set of torque rods to keep the proper alignment.
[Illustration: Fig. 130. ³⁄₄-Elliptical Rear Spring]
Fig. 131 shows the three link or commonly termed platform type of
spring used only in rear suspension on the heavier models.
[Illustration: Fig. 131. Platform Spring]
Fig. 132 shows the front type of cantilever spring. The front end of
this type of spring is bolted to a seat on the front axle, while the
rear end may be fastened directly to the under side of the frame or
attached to a specially arranged casting seat at the side of the
frame. This type of spring is sometimes employed in multiple formation.
[Illustration: Fig. 132. Cantilever Spring, Front]
[Illustration: Fig. 133. Cantilever Spring, Rear]
Fig. 133 shows the rear type of cantilever spring, which may employ
a shackle arrangement on one or both sides, while a hinged seat is
usually employed near the center or slightly over-center toward the
front end.