The Washington herald., 1921-07-10
WIRING DIAGRAMS
WILL SOLVE MOST
STARTER TROUBLE
Motorist Using Them
Can Trace Down Cause
Of Difficulty.

Trouble in the starting and light
ing system is something that fills
the soul of the average car owner
with dread. Yet careful look at
the wiring diagram of his car will
serve to unravel most difficulties,
especially IL he understands a few
basic principles, which We purpose
explaining in this story. The cleo
trio starting and lighting system of
the car usually consists of a gen.
orator and starring motor, either
separate or included in a single
unit: a storage battery, which is
charged by the generator and then
feeds its current to the starting mo-
tor and to the lamps. Then there
is a cutSut which connects and dis
connects the generator to or from
the battery at slow engine speeds,
and there is also a device to regu-
late the charging rate to conform
to the service usually demanded of
the car. These, with various wires,
switches, lamps, etc, complete this
system.
Begins with Meter.
To begin with there Is mounted
on the dash OF the modern car a
meter of some type to regulate the
charge and discharge of the battery.
so that the driver can tell how the
starting and lighting system is
functioning. When the starting
pedal is depressed the meter begins.
to register discharge because the
battery is being drawn upon for
current to turn the starting motor
over.
Sometimes the meter gets out of
order When the motor is not run
ming and when the lights are not
burning. the rand of the meter
should register Zero. II 1t does not
so register the hand is bent or the
magnet of the instrument may be
weak or the return spring may not
be strong enough. II the error is
more than a trifling one the meter
should be inspected internally.
Vibration and excessive voltage
sometimes cause arrangement in
these meters. and in this case the
car owner had better take the in
strument to the service station.
No Mechanical Troubles.
1t is not often that mechanical
troubles afflict the starting and
lighting system. Wear in the bear
ings Of the generator and starting
motor Is the commonest mechanical
i'll. Sometimes there is trouble in
the linkage or in the gearing and
in the mechanical governor. With
these troubles the car owner can
cope just as easily as those in other
parts of the mechanism.
Electrical troubles obviously are
among the commonest that occur in
this system. and they are mostly
caused by open circuits or shorts.
In the former case there will be no
flow of current at all. while in the
latter the flow will be In the wrong
direction, whereby the actual work
of the system Is slighted, as when
one uncovered wire touches another
on a different circuit.
1t is necessary to inspect the en-
tire wiring system at frequent in
tervals, because open circuits and
shorts are likely to occur at any
time. The chafing through of tho
insulation of a wire Is enough to
prevent the current from flowing to
the place whtre 1t is needed Con-
stant vigilance is the price of start
ing and lighting efficiency.
Two Methods Used.
There are two methods of running
the wires from the battery to the
lamps, etc, known respectively as
single and double wiring. In the
double wiring system two wires are
used, one to carry the current to
its place, where 1t Is needed, and
another to bring IL back to the bat
terry In the single wire system one
wire carries the current out, while
the return is accomplished through
the metal of the cars frame. II
the wire of single wire system Is
stripped of its Insulation and
touches the metal Of the car a short
circuit Is established. and the part
served by that wire will not operate
At All; II II Is lamp il will not bura.
In the two-wire system a short
does not form so easily as two
wires must be out of business TO
cause II.
The terminals are a source of
great trouble in this system. One
poor terminal connection may put
the whole system out OF order. or
1t may simply prevent one of the
units working properly. In case OF
trouble inspect these parts.
II the starting motor does not
turn the engine over snappily. and
u the lights do not burn with due
radiance. the trouble Is probably
chusedNby the battery. II the lamps
do not burn properly. but the start
sr seems to be working all right. !
the lighting end of the
system ahouIh h. fn.nx..a