ADJUSTING VIBRATORS
In adjusting the vibrators, the best guide is the running of the engine. The musical tone that they make is misleading, for a difference in the steel of which the blades are made, or in the quality of the core, will produce a difference in the tone, and because two vibrators sound alike is not proof that they are producing equal secondary sparks. With a one-cylinder engine, the adjusting screw may be turned until the engine is running at its best, while at the same time there is the smallest spark between the vibrator contacts. The adjustment of the vibrators of a multicylinder engine is proceeded with along similar lines, all of the blades but one being held down, while the free blade is adjusted until the best results are obtained in the operation of the cylinder to which it corresponds, and the smallness of the spark between the vibrator contacts. When one is correct, it is held down and another released, this process being continued until all are adjusted.