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Smoking coil!

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andy120t:
What have I done - I have an idea, but I wonder if I've damaged anything?

I bought a  spare 550 engine which I've seen bench run. Wiring was minimal. I wanted to then test it still home so wired up myself..
- power via a fuse to the coils
- trigger wires from the points to the coils
That's it. Basic wiring. I checked one spark plug using the kick start and it sparked ok, then I forgot to take the fuse (my ignition switch) out.
Faffed about for 10 minutes trying to connect a 'too narrow' fuel pipe to the carbs, then realised there was a funny smell and smoke rising from one coil. Fuse out, fire averted, no fuel anywhere. But the coil was too hot to touch.
 
Most of the wires and connectors are new, clean and cold. Just the coil is hot. I've read up a bit and had a look at the points - one side will take a .2mm feeler but not a .3mm. Other side is closed shut and this one is linked to the hot coil. So is this constantly triggering the spark?

- I assume then that this means something Is permanently occuring in that coil? Is that a permanent high current flow?
- Might the coil be ruined and what / how do I test. Just the resistance levels?
- Can I reset the closed points easily ( just by moving them to get a basic gap?) ..I haven't ever encountered them before, it's like seeing an 8 track!
- Any other thoughts about what could have caused this,mid not the above?
Thanks!

hairygit:
Welcome to motorcycling Stone Age style! If you rotate the engine on the kickstart, the other set of points should open about half an engine rotations time. Yes, the points when they are closed are energising the coil they are connected to, when they open, the coil produces the spark. As regards whether you have damaged the coil, the only was to know is try it! Smoke, to replace that which was escaping from the coil used to be available at Lucas and some auto electrical specialists, but is as rare as camera film these days

Sent from my POT-LX1 using Tapatalk

K2-K6:
"So is this constantly triggering the spark?" No, it's constantly trying to charge the coil ready to spark.

Coil sparks when points open, and from the power you've just stored in them while the points are connecting the earth route.

Let it cool and then try it to see if you get any spark from that one, then go from there if it doesn't work.

andy120t:
Right, so the points are opening and shutting ( that makes sense when you see them working  :) ) but I didn't get a spark from either coil. I've put the battery on charge to be safe so will try again later today and report back in the spark.
In the few minutes I was trying though the same coil was warming up again.

K2-K6:
Disconnect the supply on the hot one for now and then see if the other has anything wrong by trying it.

Recheck all other connection to make sure of integrity first.

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