On an old style ignition coil , 50's Harley ,6V . I read somewhere about changing the direction of the electrons ,

[xcaret]

The article was written for older English MGA sport car owners . they were positive ground ( if that matters to my question) . I was learning about hooking my ignition coil to the ground and battery , and wondering which side of the coil to connect each wire to.
That lead to my searching out how a coil works, and learning about electro magnetism, flux, and current flow, and also electrons .
An article was saying about the flow of electrons, and electrons like to flow from hot to cold ,and mentioned if you change the direction of the electrons ( I think that's what you change ) it can make the spark plug hotter ,or colder.
I have no intention of changing the heat , but I am now determined to discover all I can old ignition coils ,that were grounded through a set of ignition points .
Neil

 

[rjenkinsgb]

The coil is just a high-ratio transformer. When the primary current is interrupted, the magnetic field collapses and produces a high "flyback" voltage across the primary winding - and a proportional very, very, very high voltage across the secondary winding.

Polarity should not make all that much difference, if any.
(Connecting the wrong way changes the circuit configuration & may change the output slightly, as the secondary winding is usually commoned to one of the primary terminals - which should be the power one, not the points side).

When the points open, the coil is still connected with the capacitor (condenser) and it will "ring" briefly, producing several sparks of alternating polarity.

From a quick google search:

 

[xcaret]

Please excuse my ignorance . This is my second day researching all I can find about these coils.
I read that flux between the secondary ,and primary coil are what carries the current from the primary to the secondary coil. I had asked if the primary and secondary coils were joined by a wire . I didn't get any replies . In some of the drawings I have seen ,it looks like a wire connects them , but not in others .
One site explained that the current passed through the flux without being connected with a wire .
would that be the way some are set up , and not others ?
Thanks for your reply .
Once I got started asking merely which side the battery wire goes on, and found conflicting answers ,I couldn't stop seeking the correct answer .
That led me to seeking to understanding how a coil works . The more I researched , the more inquisitive I became .
And all I originally wanted was to hook the correct wire to the correct terminal on the coil .

Learning about this is as satisfying as assembling my old 1959 Harley Davidson .
Neil

 

[Nigel Goodwin]

Connect it the way it was always connected - the 'electron' thing is mostly just a load of crap. Makes no difference if the battery is positive earth or negative earth, as long as everything else is the same way. You used to be able to change vehicles from +ve to -ve (or back) simply by putting the battery on the other way, and pressing one of the contacts in the control box to re-polarise the field coil in the dynamo.

As kids we used to convert bikes for the field to coil ignition - strip all the rubbish ignition stuff off, and run a wire out from the points. Connect the points wire to the points connection on the coil, and the battery terminal of the coil via a toggle switch to the battery. Connect the other side of the battery to the frame - doesn't matter which way round the battery is.

Ignition coil polarity

So no electrics other than the battery and coil, and just put the battery on charge once a week or so

Interestingly if the battery did get too flat, you start to lose higher engine revs, getting slower and slower as it got flatter and flatter.

 

[rjenkinsgb]

The magnetic flux (field) carries or shares energy between the windings in a transformer, not current.
Most transformers have no electrical connection between primary and secondary, but each winding has two (or more) connections to give an electrical circuit.

With the ignition coil, both ends of the secondary winding must connect somehow, for there to be any useful current flow.

As far as I am aware, on "traditional" round can coils, the primary and secondary windings share the battery feed terminal.

I have seen some drawings that show the secondary connected to the case for grounding, but that seems unlikely unless there is a specific terminal to ensure a proper electrical connection. Newer encapsulated "coil pack" types may have different configurations.

 

[xcaret]

Thanks ,for the replies.
I get it.
I shouldn't have used the word current .
It also makes sense that windings will need a power supply .

That is about everything I still was wondering about .

 

[xcaret]

Nigel thanks for the link. It clearly shows the secondary winding connected to the power supply.
That's the link I'd found a few days ago which talked about electrons . I'll read it again, but only out of curiosity
I have learned a lot ion this site .

 

[Dick Cappels]

Yes, in many but maybe not all coils the primary and secondary are connected internally, but this is so that they can share a common ground connection. The internal connection doesn't have anything directly to do with the spark except it lets the spark return to the other end of the secondary.

From a conversation about 50 years ago the polarity of the spark had something to do with which or the spark plug electrodes would get the most deposited material and that was the reason American cars switched from positive ground to negative ground many years ago. This all from a very old memory so there may be details missing.