The daily star-mirror. (Moscow, Idaho) 1911-1939, 1919-04-01

| tanned at any position OF the electrOue,
it is evident that contact is not being
made by the points inside the cylin-
der (this is in case the other wire is
grounded directly to the engine).
Sometimes the other wire is fastened
to a piece of metal insulated from the
engine, but which touches part of the
engine for an instant when the spark
should occur in the cylinder In this
case if a spark can be obtained by
bringing the ends of the two wires into
contact it should be determined wheth
er the insulated piece is making con-
tact with the engine properly.
IF no spark is obtained at the plug
or igniter block when tested as di-
rected, it will, of course, be neces-
sary to look over the electrical system
in order to ascertain what is wrong.
| The electrical systems of various en-
gines differ considerably, and no def
mite instruction can be given for diff
ferent makes, but some general points
will be mentioned. First of all see
that the switch is in starting position.
Much time has been lost in thousands
of cases by trying to start the en-
CINE with the switch off.
Next, look over all wire connections
to see that they are tight and clean.
If the engine starts on a battery of
dry cells see that all connections be-
tween the cells are tight and that no
short circuits are caused by the me-
tallic portions of the cells touching with
other or by metal connection with
the engine, or by tools lying on the
! cells, etc. The small knurled nuts on
dry cells frequently loosen from vi
bration and thus interrupt the whole
ignition system.
Testing Battery Strength.
1t is a good thing to keep an am
meter handy for use in testing the
strength of the cells of a battery. In
| testing with an ammeter it is best to
discard all cells that do not test over
II amperes. A new cell should test |
between 20 and 80 amperes. If no
ammeter is available, a crude test can
be made by striking the end of wire
connected to one end cell of the bat
terry against the first connection on i
the cell at the other end.
Do not keep the wire in contact |
with the cell for more than an in
stant Doing so will weaken the bat
terry, but by swapping it quickly across
the edge of the knurled nut a few
times and noting the sparks, one can
ascertain whether the battery is pro-
ducing a good current. By making this
test few times with battery which
is in working condition, one can easily
learn about how much of a spark
should be expected
Oil Causes Trouble.
Sometimes too much oil will cause
trouble by accommodating on the con-
tact points in the breaker box. 1t is
usually easy to examine these points
and see if they have Oil on them; are
rough or pitted, or not opening prop
erly If oily, rinse with a little gas
olne and wipe dry. If rough or pit
ted, the points should be smoothed
with a file made especially for this
purpose. If such file is not available
q small knife blade may be used to re-
move the tiny tips of metal which
have formed on the points and to
round off the buried corners. 1t pays,
however, to keep suitable file on
hand for this work, for pitted points
are not uncommon, and unless properly
smoothed up are liable to get into bad
shape again very quickly. A gauge is
furnished by magnetic manu-
facturers to determine the proper dis
lance between the points in the open
position. The means of adjusting this
distance vary with different makes of
magnetos, but are usually apparent
upon examination. The points should
separate about one-fiftieth of an inch.
An ordinary pin is about one thirty
second of an inch in diameter and
fairly close estimate may be made u.s.
ing this fact as criterion, if no gauge
IS available.
Provide Waterproof Cover.
1t is important that a waterproof
cover be provided for the magnetic, es-
0ecially in the case Of engines used
)ut of doors, such as gas tractors, in
order to protect the magnetic from
and dust, as either of these
S likely to cause trouble sooner or
alter.
During the past few years many sta
ionary gas engines have been equip
Jed with low-tension oscillating
nagnetos Some Of these are mounted
lirectly on the igniter block, and it
s easy to test the spark by removing
he block and tripping the oscillator
With the means provided. In other
asses it is necessary. to remove the end
# the wire attached to the igniter
lock and wipe it across a metal part
f the engine, at the same time trip
ing the oscillator. 1t Is necessary
hat the end Of the wire leave the
fetal almost instantly after the oscil
ator is tripped, otherwise the spark
ill not occur. A little practice will
lake this test comparatively easy. J