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Questions on Testing Ignition Coil

fabrozor

Active Member
The ignition coil will need to be disconnected from the wiring harness at the point where the smaller wires connect to the coil. Once those are un-plugged from the coil, use a ohm-meter to test the primary and secondary windings.
1) Could you explain what primary and secondary is ?

To test the primary windings, connect the ohm-meter to the points on the coil where the wiring harness connected to the coil. The primary resistance should be about 2.5 - 3 ohms.
2) I don't anderstand what to connect to. One lead of the ohm-meter as red wire and the other connector lead as black wire. Where shall the ohm-meter red lead be plugged to ? and where shall the ohm-meter black lead be plugged to ? (please forgive my bad english speaking skill)

To test the secondary windings in the coil, put one lead from the ohm-meter to each end of the spark plug wire connections. The secondary winding resistance should be about 10,000- 13,000 ohms. You can check your manual for more specific specs on your coil.
3) You mean i shall put each ohm-meter lead between each ignition coil part where the sparkplug wire connects to ?

4) Looking at this picture, are my tests wrong ?

coil.png
 
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Re: Testing Ignition Coil

Although I'm no great expert in this area you need a hoople for that perhaps an understanding of a coil and how it works may assist you in your test
A coil for use in a petrol engine consists of a few main parts to the outside there is the primary windings this is just a lot of wire coiled together
in the centre of the coil there is a carbon rod which has wire wrapped tightly round it secondary windings
by feeding power through the primary windings from + to - through the coil connections a magnetic field is created in the coil and is maintained by the flow of power through the coil
If the flow of power through the coil is interrupted then the magnetic field collapses this collapse of the magnetic field is captured by the secondary windings and the carbon rod and will exit the coil looking for earth the easiest path to earth for the collapsed magnetic field is to move along the plug leads to the plugs where it has to jump a gap at the end of the plug (spark) and arrives at earth

I hope that helps rather than confuses

Brian
 
Re: Testing Ignition Coil

I think that would be correct

Brian
 
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