1971 Johnson 60HP outboards Service Manual, Page 33Get this manual
DESCRIPTION
The breaker point capacitor discharge (C.D ignition system consists of three major electronic componentsThese are the ignition coil, two sets of breaker points, and an amplifier assemblyThe amplifier assembly is completely sealed and is attached to bracket on the lower motor cover
DO NOT ATTEMPT TO OPEN THE AMPLIFIER ASSEMBLY AS THIS WILL VOID THE WARRANTY'!'O compliment the C.Dignition system, special surface gap spark plugs are usedThese are Champion L-77V (OMC Part Number 384751)
THEORY OF OPERATION
A transistorized voltage converter changes the 12-volt battery supply to 350 volts and stores it in the energy storage capacitorThe breaker point circuit, opened by the action of the distributor cam (see Figure 4-3), triggers the amplifierAn electronic switch then operates, allowing the storage capacitor to discharge into the ignition coilThe ignition coil boosts the 350 volts to the 25000 volts available at the spark plugsSee Figure 4-2FLYWHEEL NUT FLYWHEEL
As the crankshaft rotates, the breaker points close, allowing the transistorized converter to recharge the storage capacitor