Sparkless in Suffolk

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Atcough
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Sparkless in Suffolk

Lucky me! I've inherited a Suffolk Super Punch 14", engine number 97 3905. It had been laid up for a long time, but it has apparently not done many miles. Now I think I know why it was laid up. No sparks. I turned it over with an electric drill with the points cleaned, but not a sausage from the end of the HT lead. I've taken the flywheel off and nothing looks out of place. I'm wondering if these engines were prone to any particular electrical fault. Should I just replace the coil assembly and try again? I'm not the world's brightest, excuse the pun, spark.....

wristpin
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You mention points but not a

You mention points but not a condenser so you possibly have a coil with an encapsulated condenser . These were a bit more prone to failure. Did your points cleaning end with setting the gap and pulling a bit of clean card through to remove the products of cleaning and any grease on your feeler gauge? 

Is the HT lead screwed firmly into the coil? 

Has the coil got a kill wire connected to an earthing tab on the throttle linkage? If so it could be bent and permanently  earthing it.

Always check for a spark off the bare end of the HT lead to eliminate any plug connector issues.

Atcough
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No sign of a condenser, must

No sign of a condenser, must be encapsulated. Points were very good, no grease, slight burn, gap perhaps a thou tight. HT lead looks to be encapsulated too. I haven't checked for the ignition cut-out. Good point, thanks Wristpin! I'll check this and report back!

Atcough
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By the way, does the engine

By the way, does the engine number indicate a 1997 machine?

wristpin
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The HT lead screws into a

The HT lead screws into a socket on the coil. At the bottom of the socket there’s an outward pointing tapered screw. The lead is pushed onto it and then rotated clockwise until tight.

Atcough
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Just to show what I'm on

Just to show what I'm on about, here's an image. As you can see, the ignition cutout is the old bent tin device

wristpin
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All would seem to be pointing

All would seem to be pointing to a failed coil.

Atcough
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Thanks for the confirmation,

Thanks for the confirmation, Mr Wristpin. I didn't want to go off in search of a new part without hearing other opinions.