The Oskaloosa herald. (Oskaloosa, Mahaska County, Iowa) 1885-1919, 1916-07-13

can advance the magnetic of my car
either ne-quarter or all the way and
not change the speed Of the motor in
the least. Is the timing eorrect2
From what you say it is evident that
the control mechanism between the
steering post and the breaker box OF
the magnetic or the battery timer has
slipped or become disconnected some
where, so that when you move the ad.
vance and retard levers on the top OF
the steering wheel 1t does not really
advance or retard the spark. If the
spark were advanced all the time the
motor would be very likely to kick
back when cranking. If, on the other
hand, the spark remains retarded all
the time the engine would be very
likely to overhead when running.
! want to tighten the connecting rods
and pistons in my car by boring holes
in them. Can you tell me the size, To-
cation and number of holes to be
NADER
We do not advise the boring of holes
in either pistons or rods, as it would
be of little advantage. In drilling holes
in pistons, however, the common prac
tice is to make them one-half inch III
diameter. Either two or three rows are
drilled, depending upon the length OF
the piston skirt. 1t is usual for them
to have a pitch of about one and one
half inch. That is, the distance from
center to center of the holes should be
one and one-half inches ordinarily
The rows should, Of course, be stag
gered, and in a piston of a diameter of
about three and one-quarter inches
twentyfour holes could be put. In do
ing the work precaution should be
taken against cracking or breaking the
thin shells of the pistons when drilling
the holes. Fill up the inside of the pis
ton with lead or make block Of wood
to fit within it. thus making it possible
to drill the holes safely.
How can ! stop the rafting in the
brake bands on my carr
Possibly the brakes need refining
Also shin up the suspension points SO
that there will be no lost side motion
1t is advisable to use small coil springs
to keep the suspended parts from hit,
ting the brake drums.
! What is the most effective ratio OF
diameter to length of solenoid mag
net when the travel Of it's armature
does not exceed one-half inch7 Also,
can you give me simple formula and
an example Of it's application for wind.
ing soIenoid when the pressure to be
exerted is forty pounds working
through a distance of one-half inch,
the amperage, voltage and size of wire
used being Variable2
There Is no definite relation between
the length and diameter of an electro
magnet for any service. If an cngi,
neer were designing a mechanism re
quiring a magnet such as you mention
he would probably determine the size
and length by experiment, as such Il
problem would be difficult of proper
solution in any other way. A good
rule to follow, however, is to make a
solenoid three times the length of the
maximum travel required of it. This
is very general and might not be the
best ratio for your purpose. so that
with this as a basis to begin expert
menting you could soon discover what
the best size of magnet would be. For
the pull of forty pounds it Is certain
that the coil would have to be over an
inch In diameter.
My car has been run about 1000
miles. The timing gears, which are OF
the spiral type, howIed at first and now
I thrash. How can ! remedy that?
The second cylinder leaks oil, and the
valves need grinding very often. The
rings are in good shape, and keep the
oil level at the proper height. Could
a twisted connecting rod cause this? 1t
has a two point ignition system, and
when using both plugs ! notice a dis
tinct knock.
Replacement of the gears, which are
probably worn. is the best thing to do.
They might be loose on their shafts.
causing excessive noise.
The trouble with your second cylin-
der looks like a worn piston or one
that is slightly under size. If the
rings are in good shape try a new pis-
ton of correct diameter. or you might
ct some form of anti-leak rings TO it.
The trouble will doubtless be elimi-
mated. 1t does not seem that there is
any fault with the connecting rods
1t is well to retard the spark slightly
when you use two plugs as compared
with its position when using only one
to cylinder. When you use two plugs
to cylinder they fire simultaneously
in opposite sides of the combustion
space and thus serve to propagate the
flame a little faster than If only one
plug is used. This is likely to have
the same effect as if you advanced the
spark little. for 1t serves to put the
may imum force of the expansion, due
to combustion, at a slightly earlier
| time.
To secure best results from a motor
should the valves open and close on ex-
act dead centers of the crank shaft or
I should they open and close before or
after dead center is reached?
II is very rare instance where a
valve is opened or closed at exact cen
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