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.