The midland journal. (Rising Sun, Md.) 1885-1947, 1919-03-14

prepared by, the United States Depart.
ment Of Agriculture.)
1t is important that engine opera
tors familiarize themselves with the
bad effects produced on gas engines
by cold weather and with the easiest
ways of overcoming them, for with
such knowledge it is comparatively
easy to start gas engine in the So
verest weather.
The cold affects starting in three
ways: ~ 1t makes it harder to crank
the engine, because the oil congeals
on the bearings and around the pis-
ton and valves, (2) where a dry bat
terry is used 1t weakens the spark, 81
it causes gasoline to vaporize very
slowly or not at all, therefore makes
1t difficult to obtain mixture of gas
oline vapor and air which can be ig-
nited by the spark.
The congealing Of the Oil is not usu-
ally very serious difficulty, although
it may necessitate great deal more
effort in cranking the engine. A lit
tie gasoline or kerosene on all bear
ings which can be, reached will help.
and liberal printing of gasoline il
the cylinder will tend to thin the oil
around the piston as well as aid in
obtaining good mixture, as noted be
low.
Do Not Use Kerosene.
Kerosene will interfere with the
forming of combustible mixture. Also
where gasoline or kerosene has been
used on bearings to make cranking
easier, the engine should not be put
under load until the bearings have
had time to get well fabricated again
with good oil.
The effect of cold on the ignition
system will be noticeable only where
dry cells are used, with the exception
that where the engine is equipped
with a timer which is oileA, the con-
gealing of the oil may interfere with
the contact of the timer, in which case
little kerosene or gasoline may be
necessary to thin the oil. When dry
cells are cold they become less ac-
tive, and at extremely low temporal
lure they will cease giving current.
Therefore dry battery should be kept
in a warm place during the winter
when not in use, so as to be active
when needed. If this has not been
done it should be set in warm place
for several minutes before. attempt
ing to start the motor in cold wealth.
er.. Never warm a battery by apply
ing intense heat directly to the cells,
but allow them to warm slowly. While
in operation they will generate suffl.
cient heat to keep them active. With
cells which have been sealed in par
affin or other wax, care should be ex-
ercised not to expose them to a tenn
perature high enough to melt the wax.
Cold Retards vaporizing.
The most serious effect of cold
weather on gas engine operation is
attributable to the fact that cold re-
tards the vaporizing of the fuel. Cas-
oline as a liquid will not burn; it
must first be turned into vapor and
this vapor mixed with certain
amount of air. A thin spray of gas
Oline in warm air will quickly turn to
q vapor and mix with the surround
ing air. but at low temperatures q
considerable part of such spray will
remain a liquid, hence will not make
an explosive mixture. The remedy
is obvious. A greater quantity Of
gasoline must be furnished so as to
give off more vapOr in order to make
n mixture rich enough to be combust-
ible, or the air must be heated so the
gasoline will vaporize more readily. or
a combination of these expedients
must be tried.
If the weather is only moderately
cold, it is usually sufficient to prime
the engine in some way, that is, in
ject a small quantity of gasoline
(about spoonfuD into the cylinder,
ordinarily either through a petcOck
or printing plug, in order that more
fuel may be present, hence more va
por. Whenever an engine is primed, o
short time should be allowed for the
fuel to vaporize and mix with the air
before attempting to crank the engine.
If this is not done the vapor will pass
out a little at time through the ex-
haust valve as the engine is cranked,
and the printing will not serve its pur-
pose.
Heat Must Be Applied.
In very cold weather, however, prim-
ing with ordinary commercial gasoline |
will sometimes be insufficient, and
4.