WHAT’S THE TROUBLE WITH MY BATTERY?
With the coming of the shorter days in the year a frequent complaint
to garage man and battery or electric-system expert has to do with the
battery, though in nine times out of ten the man with the kick does
not know that it is the battery. He will talk about the lights failing
every once in a while, or the horn refusing to honk on demand. But in
the majority of cases it is the battery which is at fault.
It is more difficult to keep the battery charged at that time of the
year than it is in the summer. The reason is that the sun sets earlier,
and just as our electric light and gas bills mount at home, because we
light the lamps earlier, so it is with the auto. The driver who obeys
the law uses more current.
One complaint came from an owner who was experiencing trouble with his
electric plant. The lights would not work right when he was running.
Starting out there was light, but after running a short time there was
trouble. The lamps were fitted with dimmers and these would not work at
all times; sometimes one would light and the other fail. He went to the
garage repair man and then the dimmers would not work at all. He went
to an expert electrician, who looked over the battery and declared it
to be all right, but on the ground that he was a battery expert and not
a wiring expert he could not say why the lights would not shine and the
owner had visions of stern policemen and the possibility of having to
face a traffic judge, and he sought advice elsewhere.
In the meantime his troubles multiplied. The horn—electric—refused to
honk at times and got so that it worked only after the car had been
running half an hour or so. This was the case the writer was asked to
diagnose.
While trying to determine the cause, questions asked developed that
the owner was employed during most of the day and only ran his car
nights, except that he was making long trips on Saturday and Sunday,
and ran quite late into the night both days. During the week nights his
trips were short, with numerous stops. This caused frequent use of the
self-starter. He found it took longer to start the car, a natural
result of the cooler weather.
[Illustration: THEN HE WENT TO SCHOOL TO LEARN SOME MORE ABOUT HIS CAR]
These facts suggested that the battery was being starved; that is, that
it was not getting enough charge to keep it at its best. There seemed
to be no trouble with the wiring and the owner was told he had better
have the battery charged and see if his troubles did not end. They did.
Then he went to school to learn some more about his car.
His trouble was that he did most of his running at night and as he
carefully observed the speed laws, consequently the generator did not
generate very much extra current and the battery was being recharged at
a very low rate and being discharged at a rather high rate. In other
words, he was chopping off both ends—burning both ends of his candle.
He was using an excessive amount of current and generating less than
usual because of running at night, starting often, and running slow to
observe the speed laws. Up to a certain point, the amount of current
which goes into the battery is increased in proportion to the speed of
the car.
Generators are constructed so that they will deliver a normal charge to
the battery for normal running; they must not be constructed so they
will send out excessive current, or they will overcharge the battery,
and that is harmful. The sun sets much earlier in winter and the cool
weather makes it necessary to use the starter more. In warm weather one
little kick will start the car off; in cold weather it takes often from
half a minute to a minute.
Most engines now are equipped with carburetor check and priming devices
to facilitate starting when the engine is cold, but even with these
more current is consumed in starting the engine than when it is warm.
Then, too, the storage battery drops off in efficiency as the
temperature is lowered and will not deliver so much current on a full
charge as at a higher temperature. This comes at a time when there is
a greater call on the battery, and where a battery fails under such
circumstances, it is wise to get an occasional charge to help out the
generator.
It is becoming the practice to take all current for lights, ignition,
and other purposes direct from the battery, using a generator to
recharge it. Inside of a year at the most the bottom of the battery
will become filled with a sediment from the plates. This causes an
internal short circuit and the battery will discharge itself inside
instead of outside. At least once a year a battery should be taken
apart and the sediment be cleaned out.
Some generators are constructed so that they can be adjusted to deliver
more current on demand; that is, there is one adjustment for summer and
one for winter running. Wherever it is possible to do this it should
be done. Otherwise, when a battery loses voltage, it can be taken off
the car and be charged. It need not be necessary to leave it for a
twenty-hour charging period; if taken soon enough it can be charged in
six to ten hours, or, when the car is laid up over night. Two nights
would be enough at any rate.
As a matter of fact, in self-starter practice, everything is done to
the storage battery that formerly was included in the list of battery
“don’ts.” On account of the exceptional demands of self-starters,
batteries have been improved so that they stand this to some extent;
but the improvement has not kept pace with the extra demand put upon
the battery.
Some of the old “don’ts” are:
You should not charge the battery at a high rate when completely
discharged.
It should not be charged at a high rate when almost fully charged.
It should not be overcharged too often; occasional overcharge is good,
but not too often.
It should not be discharged at a very high rate.
Most self-starters are of the two-unit type; they have a generator for
recharging the battery and a motor for cranking the engine. In other
self-starters the two units are combined; the same instrument, when
current is fed to it from the battery, kicks off the motor and when
driven by the engine acts as a generator.
When self-starters were first introduced they had all sorts of devices
to offset the high-current demand and regulators and cutouts to comply
with the battery-makers’ directions in recharging. These devices were
complicated and could not be depended upon, and consequently were
discontinued, and it was put up to the battery to stand the abnormal
conditions. The battery makers have been trying to offset this and to
a certain extent have succeeded, but as it is directly against former
practice—for every one of the “don’ts” is disregarded in self-starter
systems—the makers have not been able to rectify conditions entirely.
On account of these conditions the life of a storage battery may be
considered to be about one and a half years, and if it lasts as long as
that it is considered to have done its work and to be entitled to be
retired.
But if your battery seems to fail with the coming of short and cool
days, do not discard it until you have tried having it recharged, for
possibly you have simply been overworking it and not feeding it enough
current to keep it in condition.