It is used in conjunction with the hammer break igniter
discussed in the last issue of GEM. The armature of this magneto
does not rotate a full circle but turned in short radius by a
pushrod, usually the exhaust valve rod, which acts against a
cocking lever attached to one end of the armature. This lever, when
released, also acts as the hammer to break the points. The base
contains two E-shaped field poles cast integral with the base. The
field poles and armature are made of laminated soft iron while the
base and end plates are of non-magnetic alloy. The field coils are
wound on the center bar of each E field pole, consist of several
hundred turns of copper wire and are wrapped with insulation cloth.
One coil end wire is grounded to the base with its other end
connecting to the other coil and that coil’s free end passes up
through the base to the terminal block. Another wire then runs from
the terminal block to the insulated igniter point on the engine.
The magnets slip down on the base and are held by a lock screw in
each side plate.
In operation, the armature, which is the inductor type with no
winding, is rotated until its two wider arms are horizontal or in a
straight line with the center poles of the field. This movement
also turns the spring lever on the opposite end of the armature
from the cocking lever so that it stretches the springs between it
and the side plates. At this time the magnetic flow follows the
least resistance from the field centers and through the horizontal
armature bars. The cocking lever then trips, the springs jerk the
spring lever straight and rotate the armature so that its X-shaped
bars line up with the top and bottom of the E’s of the field
poles. The magnetic flow thus shifts from the center of the E’s
to the top and bottom, passing through the field coils in the
process and inducing an electric current in the coil, which flows
to the breaker points of the igniter.
Troubleshooting: All electrical connections should be clean and
bright. The wire from the terminal block to the engine should have
good insulation and preferably pass through a rubber grommet where
it leaves the magneto. The armature should rotate freely. If it
rubs the field poles it will slow the rotation. The faster the
rotation the stronger the current. If it rubs, new bearings must be
made-a job for your friendly machinist. The springs must be strong
and evenly matched so they do not wear the bearings unevenly. The
hooks on the spring ends should be in the center of the springs,
not on the edges, also for even pull.
Fiber washers on each end of the armature between the end
plates, center the armature and keep it from rubbing the end
plates. The field coils are rugged and probably won’t need any
attention. Clean them with compressed air. If they should be badly
oil soaked, clean them as well as possible. Then give them a very
quick bath in naptha and dry as quickly as possible. A few coats of
shellac will help.
This is a threshing rig busy on the Frank Chaptman farm at Troy
Center, Wisconsin.
I threshed 11 days this year with this outfit which consists of
a 32 x 54 Avery Thresher and Model L. Case Tractor. In 11 days I
threshed a little over 25000 bushels of oats and 750 bushels of
wheat. Grain was very good here this year.
I also run a Birdsell No. 1 Clover Huller, and a 440 Corley Saw
Mill which I operate with an electric motor.
This old time generator belongs to John Wilcox, 17 Deland
Avenue, Columbus, Ohio. It was made by Siemens and Halske Electric
Company of America, Chicago, and is rated at 5 KW, 110 V.D.C. and
was made about 1895. John uses it for lights as his engine
buildings are a long way from the power lines. The governor of the
engine that drives the generator can be. seen in the lower right
hand corner.
If you’re restoring, the base was painted bronze and the
magnets black. Don’t bronze the wire or paint between the
magnets and base. The older models with brass base can be finished
with clear laquer if you’re a brass fancier.
Letter from Lewis H. Cline,
1102 West River Road, Battle Creek, Michigan 49017
In response to Fred McPhail, Westminster Hospital, London, Ont.
I am submitting the following:
Winnipeg Motor Contest 1912, Plowing Contest, Cost Per Acre
Rumely Oil Pull 33.7 Cents Per Acre, Average all others 50.58 cents
per acre. Also the Oil Pull rated first in rated load test, first
in maximum brake test, first in over load capacity, first in total
points and made sweepstakes winner over all other internal
combustion engines.
Official State Tractor Demonstration, Minot, North Dakota 1918:
Plowing Costs: Oil Pull 45 cents per acre, Average all others 70.2
cents per acre. Oil Pull used 21 per cent less fuel than the
average kerosene burning tractor and 9 per cent less than the
average gasoline burning tractor. Official State Tractor
Demonstration, Toppemish, Washington, 1918, Oil Pull Plowing Cost
per acre 40.3 cents per acre, Average all othes 64.0 cents. Plowed
on 58 per cent less fuel than average gasoline tractor. Ohio State
University Tests. Columbus, Ohio, 1920. Fuel Consumption test: Oil
Pull .606 lbs. fuel per brake horsepower hour, average all others
.858 National Fanning Demonstration. Fargo, North Dakota. June
1921.
Plowing and seed bed preparation Oil Pull 12-20, 39 cents per
acre, average of kerosene tractors 55 cents, average of gasoline
tractors 94 cents. The above is all the information I have at
present. There is no mention of gold medals awarded. I believe more
complete and conclusive information could be had from the
University of Nebraska, Lincoln, Nebraska.
I believe true to form in most advertising the above instances
were picked from many only those favoring the Oil Pull being
quoted.
I do believe the Oil Pull was a very efficient tractor and doubt
if it was ever beaten by very much.
Kerosene contains more heat units per gallon than gasoline,
which does not necessarily mean more power, but instead more hours
of operation on a tank full, and with the fresh oil lubricating
system (Manzel or Madison-Kipp lubricators) and the overcoming of
detonation by feeding water with fuel made a very good fuel. Not
explosive at ordinary temperatures the air or else the mixture had
to be heated, before or after carburetion in order to burn it. It
always seemed to me that heating it after carburetion was like
putting the cart before the horse. The Case 20-40 had a very good
hot air stove for pie-heating the air first.
Here is a picture of my 20-40 Oil Pull and 22′ x 3(5′
Redriver special separator.