1985 OMC 65, 100 and 155 HP Models Commercial Service Manual, PN 507450-D, Page 165Get this manual
CD IV Ignition System100 Models Description The magneto capacitor discharge system (CD ignition system consists of five major componentsThey are: 1Flywheel AssemblyWhich contains six magnetscast into the flywheel 60 apart, and sensor magnets with two poles 1800 apart located in the center hub Containing two charge 2Stator and Charge Coil Assembly coils for generating the alternating current fed to the power packs and eight A.Ccoils for battery charging3Timer Base and Sensor Coil AssemblyContaining two sensor coils 90 apartEach sensor coil has two windings on the same bobbinSensor coils and trigger the starboard side, while sensor coils and trigger the port side of the engine4Two Power Pack AssembliesContaining the electronic circuits necessary to produce ignition at the proper time: Capacitor charge circuit to store energy, sensor circuit for triggering the capacitor discharge (CD circuits and to prevent overspeed by cutting out the ignition at predetermined high rpm5Ignition CoilsWhich generate the very high voltage required to ignite the fuel in each cylinderTheory of Operation Simplified basic circuit illustrations support the theory of operation and are intended for instructional use onlyThe theory of operation and schematics for the magneto capacitor discharge ignition system use the following three basic electronic components: