the correct coil

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I think it would be a good idea to try to figure out if it has been converted to 12 volts or not. Check a few of the light bulbs for voltage (including headlamps). At this point in your build, polarity is not really that important; your choice. It just matters how you subsequently run the wires. If it were me, I'd go positive ground if it's 6 volt, negative ground if 12 volt.

Also; distributors are not voltage sensitive; coils are. The exception would be if it was an electronic distributor. You are aware that helmet distributors usually come with a built in coil.
 
tubman said:
I think it would be a good idea to try to figure out if it has been converted to 12 volts or not. Check a few of the light bulbs for voltage (including headlamps). At this point in your build, polarity is not really that important; your choice. It just matters how you subsequently run the wires. If it were me, I'd go positive ground if it's 6 volt, negative ground if 12 volt.

Also; distributors are not voltage sensitive; coils are. The exception would be if it was an electronic distributor. You are aware that helmet distributors usually come with a built in coil.
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Tubman


He has a the right 3 bolt timing cover and a 3 bolt electronic crab. I checked his crab on my Sun with my pulse generator and with out and it was dead....I think he fried the electronic trigger unit???? I have a stock helmet all set up and read to go with a spare set of caps and wires with one of the remote coil adapters that I was going to send him to use......from that point he can use either a 6V or 12V can style coil and all will bolt and hook up with what he has easy peasy as well as give him flexibility on which coil 6 or 12. THE question IS........ is a can style coils polarity dependent?? At this point I think he would be best to just run a direct wire with a 12V coil, battery and at least get it to fire and run. Thoughts
 
Thanks, it's always useful to know all of the information available. Yes, coils are polarity dependant and are usually marked "+" and "-" . If the col is hooked up backwards it's output is decreased. If you have positive ground, connect the "+" terminal to the distributor (as a points distributor grounds the circuit). Obviously, the opposite for negative ground.

Some coils are marked "IGN" and "DIST", which complicates things. In such a case, you have to find out the original application of the coil, find out whether that was positive or negative ground, and go from there.

If a coil is unmarked, you can use an ordinary lead pencil to determine which is which. The lead pencil trick is a vintage method to check ignition coil polarity: place a pencil's graphite tip between the spark plug wire and the plug, then crank the engine; a brighter spark (or flare) jumping from the pencil to the plug means correct polarity (negative at the plug), while a flare towards the wire means reversed polarity, which is less efficient and can cause electrode wear. https://www.youtube.com/watch?v=kXaOP8O4HpI.
 
Does your coil have the positive and negative primary terminals marked? If not, get one that does. Since that starter doesn't care about polarity, lets pick a polarity : negative ground. The minimal wiring is : a wire from positive battery terminal to the positive terminal on the coil. Another wire from the negative terminal on the coil to the terminal on the distributor. You will also need wiring for the starter. If it's not already wired up in the car, a long battery or jumper cable hooked to the positive battery terminal that can be touched momentarily to the terminal on the starter. Top it all off with a heavy ground cable from the negative terminal on the battery to a good grounding location on the car.

Hook up the ignition wire to the coil and touch the positive battery cable to the starter. You should see some action.

Warning do not leave either connection hooked up for very long; 20-30 seconds at most. Any longer will probably cause problems or a fire.
 
Just take the procedure I entered above and replace every instance of the word "positive" with the word "negative" and replace every instance of the word "negative" with the word "positive".

I'm getting the feeling that I don't understand what you really want.
 
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