AN AUTO FURNACE FOR WINTER
Have you a little hot air furnace on your car? You need one on frosty
mornings unless you want the engine to act as though it had an acute
attack of bronchitis for half or three-quarters of an hour. Maybe
you’ll also need to get out the teakettle and some more extras to get
started in proper shape. A lot of men borrow their wives’ dishrags also
to help start the cars. Great help, too.
There is not a bit of foolishness about this as the man who has a car
will appreciate, if he has tried to start it with the temperature
down at the freezing point and a wind blowing that would carry off
the engine heat so fast the metal would remain cold. Probably most
other folks have noticed that a lot of cars sputter and cough and spit
and pop as though all kinds of trouble were going on inside, and the
experienced ear can detect many a six-cylinder hitting only on two of
the cylinders, while many a flivver is chug-chugging away like one
of the old one-lungers of ancient auto days. Not only is this at the
start, but for blocks and even miles.
Now to a novice, the new owner, the first inclination would be to cuss
the manufacturer and the engine. It isn’t the fault of the engine at
all; it is because “the gasoline doesn’t gas.” However there is a
solution of the problem, at least enough of a remedy to make life a
little happier for the owner.
This condition of gas was absent for several years. In the early days
of automobile construction, before the manufacturers were able to
devise a carburetor for vaporizing gasoline under all conditions, we
had this same trouble as soon as the weather turned cold. Persistent
experiments produced a carburetor which overcame the trouble. Then
almost as soon as a carburetor was developed which would vaporize
the gasoline under adverse conditions, somehow the volatility of the
gasoline was found to have decreased.
You will remember the contest between armor plate and big guns—as soon
as an impenetrable armor plate was invented, some genius would go ahead
and find a powder or gun which would shatter the impenetrable plate.
Then the armor factory would try to find something to outwit the gun
maker. That is the way with carburetor and gasoline. It is time for the
carburetor maker to devise a scheme to volatilize the heavy gasoline
now supplied under all conditions—particularly in cold weather. There
are signs that he is matching up to the emergency.
It is true that the gasoline now sold has a greater heat-producing
quality, if only we can get it properly mixed and volatilized. It may
be that the gasoline producers, by putting heavier gasoline on the
market, have been of a real service to auto men, once we have learned
to utilize it economically and efficiently. They may have had in mind
the higher power, but they have given us a gas which is very hard to
vaporize on a frosty morning. Sometime soon, probably the carburetor
man will catch up and give us a vaporizer which will handle it. Until
they do, we will have to look for means of overcoming the difficulties
now experienced, and it is largely a question of warming up the air.
In changing gasoline from liquid to vapor, considerable heat must
be supplied. When the atmospheric temperature is too low, there is
not sufficient heat in it to vaporize the gasoline sprayed into the
carburetor. When the engine is warm, the process of vaporization
goes on from the needle valve to the moment of ignition, but if the
engine is cold, the process is retarded more or less, and under some
conditions it is possible for thoroughly vaporized gasoline to be
again condensed. The man who does not understand is inclined to say
uncomplimentary things about the engine and talk about “fireproof
gasoline.” The only trouble is that the temperature is so low that we
must heat the air before we send it into the carburetor. Practically
all the carburetor manufacturers put out a “stove” to heat the air
supply, which is attached around the exhaust pipe, so that the hot air
surrounding the pipe is conveyed to the carburetor, which warms the
air entering the intake, thus supplying the heat necessary to effect
vaporization. This “stove” or gas warmer, the chauffeurs are beginning
to call a “hot-air furnace.”
The process of vaporization absorbs a large amount of heat. To raise
the temperature of the liquid one degree takes a certain amount of
heat. The amount required per degree remains the same until the point
of vaporization is reached, when two hundred times that amount of heat
is required to effect vaporization. The “hot-air furnace” supplies the
extra amount of heat.
A great many carburetors have the mixing chamber water-jacketed and
the water from the cooling system is circulated through it, supplying
some heat in that way. Sometimes that in itself is sufficient, but at
present it seems advisable to use both. Neither one of these is in
operation when the engine is started; the “hot-air furnace” depends
upon the exhaust pipe being heated, and the water-jacket upon the
engine itself being heated long enough to warm up the circulating
water. So that it becomes necessary to find some means to supply heat
until these warm up.
When the car is started in a warm garage the gasoline will vaporize
properly and the engine will run in good shape, but as soon as the car
goes out into the cold air it will cool the engine so that some of
the gasoline will be condensed. Therefore we close the radiator cover
partly or wholly until the engine is thoroughly warmed. If the car is
started in a cold garage, the teakettle and dishrag method must be
resorted to. Wrap the cloth around the carburetor so that it does not
cover the air intake, and pour the boiling water on the rag, taking
care that none gets in the air intake. The hot water will heat the
carburetor and intake pipe and raise the temperature of the mixture so
that the engine will run. In some cases it may be necessary even to
drain out the cooling system and fill it with hot water, so that the
combustion chamber becomes heated up.
As the weather becomes colder it will be found necessary, no doubt,
to close up the radiator more and more in order to keep the engine at
the required temperature. High engine temperature, up to the point
where the water in the cooling system begins to boil, is desirable from
the standpoint of efficiency, and if no trouble is experienced with
irregular running, the hotter the engine is, the larger amount of power
is developed.
One manufacturer has incorporated in the radiator a shutter-like
device, by means of which the amount of air admitted may be regulated
from the driver’s seat. Doubtless others will follow, or find an
equally good substitute.
Radiator covers to fit almost any car now made may be procured at
trifling expense; one may simply put a piece of cardboard over it.
Being out without a cover recently when the engine did not work right,
the author stopped when he came to a newsboy and bought a paper and
tied it over the radiator, getting home all right with this substitute.
One man complained that his car would start out well and run all right
as long as he was going away from home, but as soon as he turned
homeward it would begin to act up. He wanted to know if the car had the
wanderlust. Inquiry developed the fact that the trips he spoke of on
the going trip were with the wind and returning against it. The added
force of the wind over the engine cooled the engine too much, and he
was advised to cover the radiator under such circumstances. He reported
no trouble after trying it.
Of course, sometimes, the skipping can be overcome by enriching the
mixture by the dash control, but with the present heavy gasoline the
enriched mixture does not seem to do much good and is simply adding to
the supply of gasoline which already is refusing to vaporize. Therefore
it seems to be the stove and the dishrag for the cold engine.