Richmond times-dispatch. [volume] (Richmond, Va.) 1914-current, 1920-08-08
.s|MPL|F|ED LESSONS IN
CARE OF AUTOMOBILE
Expert Tells OF fabrication and
Results OF Failure to Give
Proper Attention Thereto.

Whenever two things rub together.
they will, due to the friction between
the surfaces wear and overhead If
you will rub the palms OF your hands
together vigorously for a moment, or
two. you will find that they Will be-
when n dry piston is rubbed back and
Z forth in the cylinder. or when n crank
pin Is rubbed in a rotary way in It's
beeomes hot, it viii expand. and ex-
pnnding will soon bind.
4, II little oil. soap, or even water
Z he put on the hands before rubbing,
i you will find that the palms will not
, become hot. When we pu; some ma
: terial. rs an oil. grease. soap or water
as above between two surfaces to
prevent their heating or wearing, we
say we have fabricated them and that
/. the material used is a lubricant.
Two theories are advanced TO ex
plain the action OF the lubricant.
: One of these theories assumes that
: when the lubricant is between the
surfaces that II breaks UP into many
: little balls ana rollers and that the
surfaces thus are rolled on one an
other.
The other theory is based upon the
pearing surface is examined under a
microscope. the surface VIII appear
4 rough and be made up of minute par
placed together, the protruding par
tlcles OF the one Will set into the
holes of the other. The greater the
6ssSsure between the surfaces The
surfaces are now moved on one an
oSher. these pro;ruding particles Will
be Broken off. and as ;hey break off.
heat Will be generated. and OF course
the surfaces Will wear.
When an oil or other lubricant is
placed between the surfaces. It is as
these minute holes and SO prevents
the pro,ruding particles getting into
Must he Replaced.
in time the lubricant will he de-
composed and disappear and unless
replaced the. surfaces Will not be
lubricated- In machins, the luhri-
surfaces by separating them. and so
must be spread between them By their
own movement For, .his reason.
parts through which the lubricant can
enter. In order for the lubricant 10
be drawn in between the surfaces
from the hole, it must have the prop
moving surface and TO Itself or 1t
will simply remain in the hole. This
property of adherinS to other ma
Good oil has this property TO Il large
extent. while water has practically
none OF i. II you viii Insert piece
of stce! in some oil you Will find on
thickiy with the oil. while IL the steel
is put into water. when taken out IL
will have but very few drops of
water on IL. For this reason water is
not good rs lubricant, while oil
or grease Is good
II the surfaces are pressed together
under great pressure, even the most
viscos oil will not get between the
surfaces from the hole. For this rea-
son the oil hole must always be placed
at the point of least pressure. once
the oil gets between the surfaces,
because of It's roller. action, il will
quickly spread between the surfaces
which are under high pressure. Have
you ever noticed how the ankles OF
locomotive or railway car are lub-
ricated from the bottom? The weight
of the locomotive is borne on the
top of the axle, and II is matter
attempts 10 lroricate from the top
have failed. II is Cor this same rea-
son that when an automobile ME-
chanic tightens his bearings too much,
they viii soon burn out.
Method Of LulriczitiuE.
The Illustration shows the crank
shaft of an engine. with the main
As the pressure from the pistons is
downward. the top half Of ;he con-
nectins-rod bearing Will be subject
ed TO the pressure, while there will
DC but little pressure on the bottom
haf. Thus, here the oil Will have
TO ente! 81 the bottom OF the bearing
This u accomplished by having the
oil running UP IL and into the hole.
the same as water will run up your
arm when the hand IS quickly run
through il
AS The c-aak-shaft IS pressed down
on the ooito;n half OF The main bear