Ignitors
The early Oil Cooled engines had both a hot tube and ignitor ignition. Later on the hot tube was dropped leaving just the ignitor. Oil Cooled engine ignitors are nearly identical to those used by the Fairbanks Morse model N. There is no oil hole on these ignitors so be sure to oil it good on assembly.
The early vertical engines used a seemingly complex looking ignitor. The 1 and 2 1/2 hp engines used ignitors of different sizes and are not interchangeable. The stop pin is located on the inside facing the combustion chamber. A catch piece is supported between the ignitor body and a second outboard bearing. Two compression springs are used for tension and torsion.
Double Efficiency Ignitor
The People's Priced line used two different styles of ignitors. 1 1/4 hp engines used a very unique ignitor where the moveable electrode was screwed into the block like a sparkplug. The stationary insulated electrode came through the head and met the moveable one in center of the cylinder. Engines 2 1/4 to 10 hp used a more orthodox design labeled as the 1912 model in early parts books. The ignitor body was a pointed diamond shape casting, part number 2N88, which carried both electrodes and the grounding terminal. Stop pin for moveable electrode was located in end of ignitor body facing the combustion chamber. A second pin was located on the outside of ignitor body near the grounding post. This held a tension spring for the loose catch return. A rectangular pin carried in the moveable electrode shaft engaged the loose catch. A tapered torsion spring is hooked into a hole in the loose catch on one end, and a special finger on end of moveable shaft. This is a somewhat complicated assembly and the pointed ignitor body is also somewhat fragile in design. A brass stud and knurled thumb nut provided attachment for the ground, while the wire for the stationary electrode was attached right to it's end with another knurled thumb nut.
Very little information is available on the Big 4 ignitor. Only one example in a Queensland Australia museum still retains it's original ignitor. From this several more were cast and I had the chance to study these. The ignitor has an outboard bearing support with the trip catch located between it and the main body. A low tension flick magneto was used with the ignitor, but how the actual igniter trip mechanism looked is still unknown.
The People's Priced igniter was simplified and used on the model N and K engines 1 1/2 to 12 hp. They were made in two different styles, the 1913 model and regular. The 1913 model had the same pointed diamond body of the earlier 1912 model but now had the stop pin on outside of ignitor body. The loose catch was somewhat modified and a circular engaging collar replaced the rectangular key driving the moveable shaft. Loose catch return tension spring is now located between the catch and ignitor body. While the torsion spring did not change, the special retaining finger was now dispensed with. Problems with breakage of the ignitor body led to the very familiar oblong regular design. Both this ignitor body and that of the 1913 model share the same part number of 2N88A. But the regular model ignitor body is now much larger and robust. It's spring arrangement remained the same and so did that of the stop pin. Throughout the years of production this stop pin was enlarged in diameter from 1/4 up to 5/16. An oil hole for the moveable electrode shaft was now provided, later this oil hole was provided with a spring loaded brass oiler. The method of attaching the ignition wires changed too. Up until around 1919 A bent brass bracket with soldered brass screw and knurled thumb nut provided an excellent attachment point for the stationary electrode. The ground was attached with a brass stud and knurled nut. This was later replaced with a steel slotted head screw, and the fancy bent brass assembly with a fanstock clip.
Wiring Diagrams
Ignition diagram showing when points should come in contact and when they should snap open.
Diagram for the rotary magnetos.
Ignition wiring diagram for the 15B light plant engines.
