The Jasper news., 1919-03-27


With all engines using spark plugs
1t is comparatively easy to ascertain
whether the ignition system Is work.
ing properly. Simply remove plug
md ascertain that the porcelain or
other Insulating material on the inside
of the plug is not coated with carbon
and that the points are properly
spaced. One thirty-second of an inch
is about the right space for most sys-
tens where dry battery is used. This
Is about equal to the thickness Of
worn dime. A wider gap will often
make starting difficult, especially when
the spark Is rather weak or where a
high tension magnetic Is used. In the
latter case the best results will often
be obtained when the gap is not more
than one-fortieth or even One-fiftieth
of an inch. Then re-attach the wire
and lay the plug 50 that the metal
base touches the engine casting, while
| the end OF the wire and the metal
| tip Of the plug are at least half an
| Inch from any metal part connected
! with the engine and in such Il posi-
| tion that the points are visible while
crnnking the engine. Then turn the
engine over u few times Cat least as
many times as there are cyllnders)
and note whether spark jumps across
the space between the points. 1t Is
not sufficient, however, merely to as
certain IL there is spark-it must
be hot enough to fire the compressed
charge In the cylinder. 1t Is, of course,
difficult to tell by merely looking at
1t whether the spark is hot enough
or not, but II it Is heavy blue. or n
bluish-white, or a "fat" yellow one
looking like n small flame, 1t is prob
ably all right. If very thin and green
ish or showing rcd, the chances are
1t Is too weak to fire the charge. One
may famlliarize himself with the as
pect of good spark as follows:
Finding Good Spark.
While the motor is in satisfactory
running condition loosen the nut on
the top Of the plug while the engine is
stopped so 1t will be easy to remove
the wire from the plug after the en-
CINE Is started. Then start the en-
|
where 1t Is covered with insulation.
move the end Of the wire very slowly
away from the center of the plug ana
watch the spark jump, closely observ-
ing its color and thickness.
1t Is also well to note the distance
the spark will jump, yet not advisable
TO force IT To Jump too great gap
| oh Il ,I,. i 80 81, ,..t, l. ii
lowed to rest in position where the
tspnrk cannot tump-to the plug or the
engine while the engine is running, as
this tends to break down the insuin
ton of the coil. In the case Of high
tension magnctos there Is no danger
In this respect as they are fitted with
a safety spark gap which the spark
is broken elsewhere.
Knowledge of Just how much of Il
spark one should obtain with each
kind of ignition system is frequently
of great value In locating trouble, and
everyone who operates a gas engine
should make the above-described tests
while the engine Is in good order. II
| Onc Is nut SVIllClcNNly lNlIilluI Will
the looks of good spark to tell by
mere observation whether 1t Is hot
enough, rough test may he made
as follows: Place thin piece OF
dry cardboard such as an ordinary Wis
itlng card, or three or four thlcknesseS
of dry newspaper, between the points
Of the plug while 1t is lying on the
engine In the position first mentioned
then crank the engine. A good spark
will Jump through these, leaving &
tiny hole. A spark which will not Dc
this is too weak to jump the sparl
gap In the cylinder under compress
sion.
If the engine is equipped with {
make-and-break Ignition system. II
which an igniter block is used insteat
of spark plug, II can be ascertalnet
easily whether the entire system, witt
the exception of the igniter block, |: