Author Topic: Failing coil  (Read 317 times)

Offline Ken4004

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Re: Failing coil
« Reply #15 on: Today at 03:52:55 AM »
Just found this spark plug tester on eBay, not sure if it’s any good but it looks like a fairly basic device so it’s probably OK.


Offline Bryanj

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Re: Failing coil
« Reply #16 on: Today at 06:24:00 AM »
That does not test the spark plug it test wether the coil is giving a good spark

Offline K2-K6

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Re: Failing coil
« Reply #17 on: Today at 09:21:54 AM »
Put a spare plug in a lead  and start it with that held to earth, will verify you've got coil output.

Offline Bryanj

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Re: Failing coil
« Reply #18 on: Today at 11:19:08 AM »
Better if you remove the cap and see how far the spark will jump from ht lead to head, from old memory 3-4mm is a minimum

Offline Ken4004

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Re: Failing coil
« Reply #19 on: Today at 11:21:02 AM »
That does not test the spark plug it test wether the coil is giving a good spark

Yes you are correct I meant to say coils , sorry for the confusion

Offline Athame57

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Re: Failing coil
« Reply #20 on: Today at 05:04:20 PM »
I've dug up a coil from the depths of my spares pile and fitted that, all is now fine.  ;D While the spanners where out I put a new starter solenoid in too  ;) as issues had started with that as well.
I brake for animals!
1978 CB400F2 named Elen.

Offline McCabe-Thiele (Ted)

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Re: Failing coil
« Reply #21 on: Today at 05:49:39 PM »

I've dug up a coil from the depths of my spares pile and fitted that, all is now fine.


Could you see any visible cause on the coil you changed such as casing cracks or HT leads cracks?
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