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Eisemann

Eisemann made some very fine ignition equipment. The early products had  pot metal issues on some models but if all is well mechanically, they are excellent magnetos. Caterpillar used many Eisemann products as OEM for their gas tractors and later for pony motor ignition on their Diesel tractors. Many Caterpillar tractors of the day have original magnetos.  Eisemann also made many flywheel magnetos for the small air cooled engine market including outboards, and the Maytag twins.

 Now that is service!

Who better to service your Eisemann magneto than a shop using genuine factory service parts located in Zap, North Dakota!

Here is a mini catalog of Eisemann products in 1923 .

The model G4 was a very popular model and many survive today in working order. They were hot even when all was not well. The condensers seldom failed. They suffered from the usual woes of sticky goo with a wound armature and seldom lacked for output. There were some pot metal issues and use of special pitch metric threads everywhere. Here is an mid production advert for the G4.

Stay away from contact files. Everyone has one it seems. they are too coarse, leave a rough surface that will readily corrode and remove too much material. These points are also made of unobtainium.

If anyone knows where fake parts can be found please  let us know!

  A pet peeve of mine and others  and cause of many discouraginfg words concerns how Mr Eisemann decreed we connect ignition wires to the magneto in earlier models.  The distributor looks straightforeward enough, just plug the wire in??  But foresooth, the hole where the wire goes into the distributor plate is too small to accept the brass ignition wire end terminals of the day.This was not a compliment!  Some models like the G4,GS4 and GV series found on early gas caterpillar tractors were connected by removing the carbon collector brush and removing a screw under it, then putting a stripped wire into the post, then tightening the screw on the wire, then replace the carbon brush without losing or distorting the spring.  If you look at the inside of the distributor plate near the brushes will be scrawled something like "Strip Cables to 11/32" or 3/8" to accomplish this.

Another annoyance is when things got wet and the brush, spring and the screw decide to seize in the fragile brushholder. The screw is a 10-32 . If this happens (and it may) the best plan is to make a drill bushing that fits in the brusholder center drilled for the tap drill for 10-32 and go cautiously so not to go to deep, then carefully drop in with a 10-32 tap. In place of the special steel retainer screw a short 10-32 Allen head stainless steel setscrew works well.

If the wires are merely  poked into the distributor plate as we have encountered, the spark must jump about 1/4" from the brushholder to get to the wire and can cause poor starting and damage the coil. These images are from an Eisemann owners manual. Some distributor plates for the GV series had taller posts and did accept the usual brass ignition wire terminals, but most did not unfortunately.  Some versions of the G4 distributor plate were not as annoying by allowing the wires to be inserted and fastened by tightening brass hex nuts that were around the brushholders and drawing down on the stripped wires.

Another area of concern relates to the length of the mounting bolts. If the bolts are too long they will damage the base and the pole shoes. This can be a huge problem with any base mounted magneto. These are images from an Eisemann service manual.

Remember the stop switch for safety's sake. Some caterpillar engines had different firing orders, some are 1243, others 1342. The rotor turns clockwise when faced from the operators platform. You may line up the rotor by turning the magneto backwards.