SJM No Spark

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andrew
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SJM No Spark

Post by andrew »

A bit miffed on this one.

Have an SJM I’ve worked on and I just can’t get a spark out of it. Replaced the villiers coil with a good one that reads 4.5K ohms secondary and 0.8 ohms primary and gives a good spark on another SJP. Removed the condenser and tested it at 0.23 micro Farads, right where it should be. Very clean baseplate and points box. Points clean and gapped properly. New HT lead and pickup/boot, good continuity on all bits. New spark plug properly gapped.

Any suggestions on next steps? I can’t think of what else to try! I’ve taken my time on this one and thought surely it would give a good spark today but no luck so far.
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Stelios_Rjk
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Re: SJM No Spark

Post by Stelios_Rjk »

Maybe the magnets are dead in the flywheel? If you try with another flywheel?

I suppose you are using the correct flywheel that matches with the villiers ignition system.
I love the 10600/145 turns!!!
andrew
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Re: SJM No Spark

Post by andrew »

Believe the magnets are OK but will try another flywheel just in case. Thanks for the suggestion.
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Stelios_Rjk
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Re: SJM No Spark

Post by Stelios_Rjk »

Happy to help.

Also the key that holds the flywheel in place, is it correctly positioned?

The timing screw is it inside the notch?
I love the 10600/145 turns!!!
andrew
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Re: SJM No Spark

Post by andrew »

Figured out it was the spark plug boot. Brand new rubber one, usually they work well. But this one wasn’t snug enough around the plug to get a spark despite having continuity when tested, a risk when not using a screw on type connector I guess.

Ended up pushing the spark plug outside the metal connector but still inside the rubber boot, instead of in the middle. This gives it a good enough connection to test. Bright blue sparks from then on!

Will swap it for a BS one and all should be good.
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Oyster 49
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Re: SJM No Spark

Post by Oyster 49 »

Good to see it is fixed, its often the simple things! Good to hear from Stelios too!
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