Ignition and Starting Systems Magneto breaker point opening relative to the position of the rotating magnet and distributor rotor (internal timing) can be set most accurately a. during the magneto-to-engine timing operation. b. during assembly of the magneto before installation on the engine. c. by setting the points roughly at the required clearance before installing the magneto and then making the fine breaker point adjustment after installation to compensate for wear in the magneto drive train.