The Washington times. [volume] (Washington [D.C.]) 1902-1939, 1926-09-29

case cooling. 1t cannot be too
strongly emphasized, however. that
they all can stand some variety OF
crankcase ventilation.
All lubricating oil held at the
bottom IF the crankcase and clr-
culating through the engine system
is contaminated. First there aie
the abrasives from wearing metal
parts. Second, there are the I'M
purities in the oil itself. Third,
there is the gasoline diluent caused
by leakage of raw gasoline into the
crankcase when the engine is being
started. Fourth. there is water
from condensation of vapors when
the engine and the crankcase cool
Fifth. there are acids. particularly
sulphuric acid, developing as re-
suit of the presence of water
1t has been demonstrated. that II
these undesirable aliens can be
kept out of lubricating oil, it can
be used almost indefinitely. II
fact, many operators of trucks for
a long time have made a practi. e
of drawing off oil at night. rectify.
ing and filtering it. and then pour-
ing it back into the engines in the
morning. This plan, however. Is
not ideal because much of the wear
and tear on engines occurs during
the time oil is starting to get dirty
or diluted.
Motorists should study the various
crankcase schemes on the 1927
cars and should then come to a
conclusion. They should make up
their minds that, all selling talk
to the contrary Notwithstanding.
no one feature will keep out Of
oil Ill 80 -
tamination.
Merely drawing fresh air through
the crankcase and expelling it
under the car will not take out
impurities and keep the oil free
of gasoline. This process Keeps
the crankcase cool, if that is de-
sired or necessary in a particular
type of engine, and it also carries
off much water and gas vapor
which might condense and 1ilute
the oil. Simply rectifying' oil by
sucking it from the pistons or
from the oil supply does not elm !.
mate all the dirt. Merely filtering
oil does not take out the gas
diluent.
tits essential to have a combina-
ton of devices to keep the oil IN
perfect condition. What is of great
car owner is the fact that all of
these devices can be bought and
installed, and at small expense
compared with repair bills.
In some cars, crankcase vapors
are being drawn off by the air
draft created by the forward move
ment of the car. In others the
air intake of the carbupetor is
utilized for this purpose. The
latter arrangement is preferable be-
cause in this vapor much useable
fuel vapor and oil is held in sus-
pension. Drawn through the car
buretor into the engine, the vapnr
can be burned while the oil assists
In lubricating cylinder wallss pistans
and valves.
Only an oil filter, however, win
take out the actual gritty dirt and
abrasive in the lubricant. Only
a rectifier that boils the oil on
the exhaust .stove'' will take out
all the gasoline in the oil. These
are facts which every motorist
must face when considering a new
rar and anticipating the ultimate
in engine and oil efficiency.
Where crankcase vapors are
drawn off it may or may not be
necessary to use a breather tube
TOT the OIL air 10 EGDtd(sS
that which is removed. If
breather tube is used 1t must be
equipped with a small air cleaner,
otherwise dirt will be drawn nto
the case. If no breather tube is
used, care must be exercised not
TO suck off too much vapor or 10
apply too much draft. A partial
vacuum in the crankcase would
permit gas vapors and exhaust
gases to blow by the pistons too
freely.
Some engines are designed to
build up a little pressure in the
crankcase to prevent "blowby"
when the engine is cold. The
newer thought in crankcase design.
however, suggests aba ndoning this
idea for ventilation plus oil recti-
'ication and filtration. In time,
oil aeration will also come into
vogue, for when oil is used for
thousands of miles it will become
necessary to rejuvenate it now
and then through contact with
fresh, live air.
Big things are happening around
the crankcase. Watch them. Study
them. And remember that .one
feature cannot solve all crankcase
problems.
Do you need any help in your office?
M