What is mercury marine cdm

Mercury Outboards electronic module, the Capacitor Discharge Module, controls spark to the engine. Since the early 1960 is most outboards have used this type ign. It is more dependable than points, condenser.But You have to take care not to cause power surges, like jump starting with cables, etc. and no loose wires.

Mercury CDM ignitions use a combination switch box/ignition coil, as distinguished from other capacitor discharge ignitions having separate coils for each cylinder.