Ever wonder why Webster put that bolt on the igniter movable electrode (anvil), as seen sticking out on the left of Figure 1? Why didn’t Webster put a bump on the casting or the push-finger (hammer) seen in Figure 2? The bolt is seemingly too long if its only function is to compensate for wear. Actually, the bolt is for timing adjustment. Timing is the location of the piston, or flywheel, when the igniter trips. Generally, the igniter should trip 5-to 8-degrees per 100rpm before top dead center (BTDC). There is, however, a second timing adjustment even more important than BTDC. The second timing requirement is the rotational location of the magneto armature when the igniter trips.
All low-tension magnetos
