“two output coils” … I call these “ungrounded secondary coils”. There is some confusion / mis-understanding surrounding these coils. In a single output coil, one end of the secondary winding is grounded at the side of the coil, the other end of the winding is your spark plug wire…. thus creating a “loop” circuit. With the two output coil each end of the secondary winding goes to a spark plug wire… so, you might ask, where is the loop circuit? With this arrangement, the loop includes the entire engine block. The electrical circuit is this, those little electron guys leave one end of the secondary winding, jump the gap in the first spark plug, travel through the engine block, jump the other spark plug gap and then back to the opposite end of the secondary winding.
Since the “loop” includes BOTH spark plugs , it is very important that when pulling over a motor with this “ungrounded secondary” ignition system, to be sure that both wires are are connected to form at complete loop circuit. To not do this, risks damaging the coil.
Testing with a ohm meter, connect test leads to both spark plug wires. The reading should be about as in a single output coil…somewhere in the range of 4500 to 7000 ( 4.5 K – 7K) ohms.
As in any coil the primary winding will show a very low resistance… like 1.5 – 2 ohms
Hope this helps…
Joe B
