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Battery Powered Ignition Coil Answered

I have a few lawn mower ignition coils lying around, so I thought I would make something out of them. The problem is I do not know how to make the coil run off a battery. Here is a picture of the coil. I would greatly appreciate any help.


Yeah, that's a Briggs and Stratton solid state magneto module. If you carefully grind(not cut) your way into the little nub between the round part (the high tension winding, with the low tension copper wire winding inside that) you'll be grinding end-on into a third iron rod with aluminum hair-wire wound around it and a transistor called a Silicon Controlled Rectifier. As you get within a millimeter or so of the laminated iron pole shoe (remember: a little at a time) you'll see the small copper wire that is the ungrounded end of the low tension coil. If you cause the pole shoe to be Zero Volts of a car battery and connect 12 volts to aforesaid wire - a spark on the order of 12mm will jump out of sparkplug wire to zero volts when the 12v is disconnected. If you keep 12v on the primary more that 10 seconds it will overheat. A practical ignition would then require a 10 ohm 10 watt resistor, a .1 microfarad capacitor connected across your 12v "switch" - and an engine still equiped with breaker points.(now rare) I prefer to take a small single pole double throw relay and connect it so the closed contacts power itself open - connect the coil to this chatterbox and you have a miniature Model T "induction vibrator" ignition!

hi, you cant make them run of a battery , the spark is produced when a magnet in the flywheel goes past the coil. it is a magneto.

when you quickly connect and disconnect battery and coil you get a voltage kick try it with 9 V battery and magnetic 36 W fluorescent lamp ballast. if you touch both wires when disconnecting from the battery youll jump

umm how can u connect it up to a battery , when there is only one wire connecting to it ? theres the high tension lead and a single wire coming of the magneto.

you CANNOT connect it up to a battery..


9 years ago

To run an ignition coil you need to switch the power on and off as "sharply" as you can- a square wave is ideal. You can build circuits to generate a square wave from a 555 timer and some assorted bits and pieces but that usually requires buying electronic components, soldering, fault finding etc... The simpler solution is to use a dimmer switch but I'm not sure if a mains dimmer switch would work on 12V. Here's a thought- does anyone know if an audio output will drive a power transistor? If it can, why not get your computer to output a square wave tone and wire that to the base of a power transistor feeding the coil? Other than, you know, the possibility of bricking your entire computer, but an opto-isolator should sort that out.