1970 Johnson 1.5 HP Outboard Motor Service Manual, Page 26Get this manual
4-3 hasten the collapse, condenser in the primary circuit absorbs the current which would otherwise across the opening breaker pointsThe rapid collapse induces current of sufficient voltage in the secondcircuit to across the spark plug air gapThe condenser, which acts like storage tank, consists of thin sheets of metal foi1 separated insulation, rolled to save space and enclosed in metal caseOne sheet of foil is grounded to the case, the other is connected through an insulated wire to the insulated stationary breaker pointSPARK PLUGS Spark plugs having the heat range very i.nportant for peak operation of the motorThis motor is designed to operate with J4J spark plugsSpark plugs classified according to the temperatures at which they designed to operate, COLDSee Figure 4-2Selection of the correct spark plug depends the type of service to which it is subjectedUnless the spark plug is properly suited to the motor, trouble arise which might interpreted as carburetor difficultyVery low trolling speeds will tend to foul plugs due to the not burning from the However, at full throttle with hotter plug, the operating temperature too high, resulting in ignitiondifficult to control with one plugAn extreme temperature range will Spark plugs furnished with the motor selected for average serviceSpark plugs recommended for the 1-12 HP Model 1Champion: J4J 2Figure 4-2Hot and Co1d Plugs Figure INSULATION FOIL