Suffolk fabric wrapped coils

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suffolkalan
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Suffolk fabric wrapped coils

I started this new thread as the information would have got lost in my 'dating a Suffolk engine' post.

Being faced with an open circuit early fabric wrapped ignition coil I searched in vain for a secondhand working replacement and I didn't want to purchase another engine for spares.

I obtained locally a later Wipac coil/lamination assy for £20 with a view to making it work.

I dismantled my original lamination assembly by removing the rivet heads and punching them through, the later stator pack is a fair bit slimmer than the earlier type and I found 12 sections would fill the coil aperture but was too wide.

I cleaned the surfaces of the laminations and lacquered one side to insulate them from each other once dried sufficiently they were riveted together to make the stator pack, the centre  was  machined down to a width to slide into the new Wipac coil. A new spring steel retainer was made from an old recoil spring.

Sufficient to say I know it was a fair amount of work but I am glad to report that my new assembly gives a nice spark!

Result.

 

Alan

wristpin
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That's a good mod or what I

,That's a good mod or what I belive is now referred to as a "hack"! I see that you have even managed to eliminate the condenser by using a coil with the encapsulated one.  I'm not sure that it's necessary to lacquer between the laminations; when I'm asked to test "naked" coils I just put a bunch of wire nails through the centre to provide the "soft iron core". 

Chris G
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Very clever idea, well done

Very clever idea, well done and looks well done!

suffolkalan
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Joined: 02/07/2019 - 21:04
Thanks for your comments!

Thanks for your comments!

Won't start though!

Got good compression and spark but only managed a few firing strokes and the exhaust smoke is very white in appearance? Almost like it's running on paraffin!

Suspect a carb problem although it has had a proper dismantle and clean. Such a simple device!

 

Alan

suffolkalan
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Well holidays stopped

Well holidays stopped progress!

Still can't get it to run, swapped carb parts from a good running engine but all I get at best still is a few whitish smokey exhaust cycles, no 'firing' as such.

Decided my coil mod doesn't work, it will give a spark with the plug resting on cylinder head but I think it is not got enough energy to do the same under compression.

So now looking for a replacement - anyone got one spare?

 

Alan

wristpin
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It’s possible that your

It’s possible that your existing flywheel is not compatible with the more modern coil and not generating enough voltage into the primary winding to induce the 20k or so voltage in the secondary when the points trigger it.