The Aberdeen weekly., 1919-03-28

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 cnses 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.
III 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-
tallfc 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.
meter handy for use in testing the
strength of the cells of battery In
testing with an ammeter it is best to
discard all cells that do not test over
- amperes. A new cell should test
between 20 and 80 amperes. IF no
ammeter is available, crude test can
be made by striking the end of a wire
connected to one end cell of the bat
terry against the first connection on
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 n few
times and noting the sparks, one. can
ascertain whether the battery is pro-
ducing a good current. BY making this
test Il few times with Il 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 little gas
oline and wipe dry. If rough or pit
ted, the points should be smoothed
with a file made especially for this
purpose. If such fi;e is not available
Il 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 a 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
generally furnished by magnetic manu-
facturers to determine the proper dis
tance 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
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 US
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-
pecially in the case of engines used
out of doors, such as gas tractors, in
order to protect the magnetic from
moisture and dust, as either of these
is likely to cause trouble sooner or
later.
During the past few years many sta
gas engines have been equip
ped with low-tension oscillating
magnetoS. Some of these are mounted
directly on the igniter block and it
is easy to test the spark by removing
the block and tripping the oscillator
with the means provided. In other
cases ii is necessary to remove the end
of the wire attached to the igniter
block and wipe it across a metal part
of the engine, at the same time trip |
ping the oscillator. 1t is necessary
that the end of the wire leave the |
metal almost instantly after the oscil- |
lator is tripped, otherwise the spark |
will not occur. A little practice will |
make this test comparatively easy.