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testing coils

Charging System, Wiring, Lighting
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jaybee56
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testing coils

Post by jaybee56 » Mon Dec 17, 2012 8:54 pm

I have power at each side of the coil but no spark from plug wire to ground?
I suspect the coils bad, bike has been sitting for 40 something years. Is there a test to check the coils?
thanks Jaybee56

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Snakeoil
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Post by Snakeoil » Mon Dec 17, 2012 9:22 pm

With 12 volts to the coil, you can simply lift the ground wire and it will simulate the points opening. If you get no spark from the HT lead with a grounded spark plug, coil is dead.

regards,
Rob

jaybee56
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Post by jaybee56 » Tue Dec 18, 2012 9:00 am

I will give that a try, thanks for your help!
Jaybee56

davesdreamin
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Post by davesdreamin » Sat Apr 27, 2013 10:02 pm

Snakeoil wrote:With 12 volts to the coil, you can simply lift the ground wire and it will simulate the points opening. If you get no spark from the HT lead with a grounded spark plug, coil is dead.

what do you mean "lift the ground wire?"

On another note, do condensers typically need to be replaced? Is the only way to get to it to drop the engine or bend a screwdriver to get to it?

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G-Man
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Post by G-Man » Sun Apr 28, 2013 12:37 am

Lifting the wire means - detach it from the terminal. i.e. break the circuit. This is what the points do...


Condensers simply snub out the arc as the points open / close. They do occasionally (like everything else) fail.


G
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