Re: coil assembly and ignition coil assembly
Your 9.5 has the OMC "Universal Magneto" that was used for many, many, years. It has two coils under the flywheel. Each of those coils has both a primary winding for generating the electricity and a secondary winding for boosting the primary voltage up to the thousands of volts required to fire the spark plugs.
Not knowing the year of your 15, they had two other types of igniton: "Low Tension Magneto", and "Capacitor Discharge Ignition".
Low Tension Magnetos have just one primary coil under the flywheel, which generates the electricity. The two secondary coils are mounted outside. They work more or less the same as the Universal Magneto, except the secondary parts are re-located.
Capacitor Discharge Ignition is a whole different ball game. A "charge coil" under the flywheel generates 300 volts, as contrasted to the Universal's approximately 6 volts. That 300 volts is stored in a capacitor inside a unit called a power pack. Another unit under the flywheel called a sensor figures out when it it is time to fire the spark plug and sends a signal to the power pack. That signal tells the power pack to discharge the 300 volts from the capacitor to one of the externally mounted spark coils where it is boosted to the thousands of volts required to fire the plug. The obvious big difference here is the spark coils are driven by 300 volts instead of 6 volts.
Hope this helps without getting too technical.
