Graham guardian., 1918-03-15
ZERO COLD TEST FOR MOTOR OILS


During this cold weather we find
that our motors do not respond
as quickly as is the case during
the summer. Lubricating oil is
partly responsible for this con-
dition. This annoyance of a
sluggish and inefficient motor
can be largely eliminated by the
use of the correct oil, says P. r.
Melchert, Automobile Engineer
of the Standard Oil Company.
For correct cold weather lubri-
cation the cold test of a motor
oil is a most important feature.
Upon it depends very largely the
flexibility, power developed, fuel
consumption and wear and tear
of the motor.
The cold test of an oil is the
lowest temperature at which it
will flow; for instance, if an oil
has a cold test of 80 degrees it
will pour at that temperature
and become solid about 5 degrees
lower.
Oils that CONCEAL when the
weather is at freezing point, or
at 80 degrees F., are not suitable
for lubrication during cold wealth
er, because the resistance offered
to the sheering of the film is
high, for we learn that the value
of a lubricating oil depends upon
its fluidity at the temperatures
at which it is used; that is. a
fluid oil, or one having a good
cold test preferably zero), will
offer very much less resistance
to the sheering of the film than
a thick or sluggish oil or one
that has a poor cold test and is
in the condition of jelly in the
crank case.
We know that all gasoline en-
gines start hard in cold weather
because the fuel does not vapor-
ize as readily at this time as it
does during warm weather, tax
ing the batteries to their limit.
If poor cold test mbricating oils
are used, the additional power
necessary to turn the motor over
is very materiallyincreased which
means rapid draining of the bat
teries and, consequently, ex-
pensive upkeep.
Again, If an oil of poor cold
test is used, or one that congeals
in the oiling system during these
cold mornings, it will not lubri-
cate the motor correctly because
it is too thick or sluggish to pass
between the close fitting bear
ings, and if used in a motor
which is partly or wholly lubri-
Gated by splash, this oil will not
be splashed to the cylinders,
pistons and wrist pins in suf-
ticient quantities to insure ade-
quate fabrication until the motor
has been run from Is to 80 min
utes and the temperature of the
motor has thinned the oil down,
during which time excessive
wear of the moving parts is TAX
ing place which means not only
expensive adjustments and re-
pairs, but also excessive fuel con-
sumption, and a sluggish and in
efficient motor.
This also applies to force-feed
oiling systems, for oils of poor
cold test offer considerable re-
sistance to the passing of the oil
through the pipes and hollow
crank shaft to the bearings, and
the oil does not circulate freely
enough until it has thinned down.
Another condition which shows
the inefficiency of poor cold test
oils very plainly to the operator
is the necessity for frequent gear
shifting.
Eastern refners and motor car
manufacturers recommend light
oils for winter and medium oils
for summer fabrication, realizing
that oils of poor cold test cannot
be used successfully during cold
weather. They are compelled to
do this because light Eastern oils
have a better cold test than med
ium-bodied Eastern oils. .
Motor oils correctly manufac-
tured from California asphalt
base crude have a natural zero
cold test, making them the cor
rect oil for use at all seasons of
the year.
Using zero cold test oils gives
the necessary margin of safety
so that during this cold weather
there is no danger of burned out
bearings or excessive wear of
moving parts, caused by lubrica-
ting oil congealing in the oiling
system.
1t is reported from Germany
that wood is being largely used