The fun way to test ignitors and coils!


I don't like the haynes manual lightbulb idea to test ignitors. It seems kinda dumb if you ask me. Besides, lots of people say they try the lightbulb technique and it doesn't work, but the ignitor still works. Did they use a burned out light bulb? Did the writers/publishers simply pass incorrect info on to us?

Well, whatever the reason, I have a really cool way to test ignitors and coils.

I recently purchased 5 used '81 to '85 electronic ignition coils from a local rotary shop for use in converting some vehicles around my place to direct fire.

I needed a quick way to test them without going through the hassle of installing them, firing it up, seeing if it will run right, shutting it down, pulling them out, installing the next ones etc. So I just used an old RX-7 distributor wiring harness and pluged it into a known good ignitor and hooked the other end to one of the coils and used an aligator clip to connect the + of the coil to battery + and another aligator clip went from the aluminum backing of the ignitor to the - of the battery. I used an NGK plug wire with a BR8EQ-14 plug held in a visegrip with another - aligator clip hooked on the handle to complete the ground path circuit.

The cool part was hooking mini aligator clips to the pins on the backside of the ignitor to an old 4 inch speaker that came out of a GSL-SE. Just make sure that the + and - of the ignitor are hooked to the speaker correctly. If not, it will work better if you push the cone upward (not as easy as tapping it downward). Just try it one way, then the other way untill it works. Each time I would tap the speaker cone with my finger, it would spark the plug! A big woofer with a stiff cone works even better!

I tested 5 coils very quickly this way. To test lots of ignitors, simply swap them out one after another like I did with the coils.

The above wiring can also be accomplished with only aligator clips if need be, but I used jumper cables on the battery terminals because they have larger jaws, then hooked aligator clips to the thin metal of the jumper cable jaws. The B and C connectors on the ignitor are easy to remember. B goes to the + of the battery, and + of the coil. C goes to the - on the coil only. The way to remember it is, the + of the battery goes to + of the coil and B (which means battery), which leaves the - of the coil open to C (which means coil). That sounds kinda complicated, but it's really not.

Remember to pay attention to the back of the ignitor for heat (mine stayed cold, even after tapping the speaker to the beat of a popular song). If they heat up, you'll have little time to disconnect them. I know this to be true from personal experience. Just pay attention and wire it up correctly. They will stay cold to the touch (even after a drum solo :)).




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