The rocker arm (412) is provided with a Screw (419) and locknut for adjusting the "latch-off" of the trip finger. This screw must be set so that the latch (407) will slip off the lip of the rocker arm just after the breaker points have been opened by the downward movement of the armature.

If the screw is screwed OUT too far the breaker points will not open and the magneto will not spark.

If the screw is screwed IN too far the trip finger will drive the armature down too far and possibly break the return spring or the pants that hold it.

This adjustment will be made originally by the engine builder and should not require attention thereafter. It has nothing whatever to do with the time of the spark.

If necessary, the adjustment can be made as follows:

Trip the armature (100) from its contact with the cores (107) and insert a strip of metal 7-64" thick between the armature and the face of the cores. Move the push rod slowly until the latch of the trip finger reaches the rocker arm. The edge of the latch should then just engage the edge of the lip of the rocker arm, and the adjusting screw (419) should be bearing on the top side of the latch, (see Figure 16) so that the least further movement of the push rod will cause the latch to slip off the edge of the rocker arm.

If the latch does not engage the lip of the rocker arm when armature is set as shove the adjusting screw should be screwed in until the latch just engages. If the latch engages the lip of the rocker arm too much (more than 1-32") unscrew the adjusting screw to give the proper engagement.

Loosen the locknut on the adjusting screw (419) before attempting to change adjustment and be sure to set it up tight after the adjustment has been made. Remove the metal strip before attempting to start the engine.

(See Figure 18)