Coil questions.

[arcturus]

Hi, as a matter of interest would a 12 volt coil work in a 6 volt system and vv. Would it work at all, just or burn up and die?
Question number two. Are there any marking to indicate 12v or 6v on the armored coil used in PVs etc? I have a coil and the only marking is the number 4 below the Bosch symbol

[Pigeon]

A 12V ballasted coil and a 6V unballasted coil are basically the same thing and are interchangeable.

A 12V unballasted coil is different. It will not work in a 6V system - chances are it'll still make a spark, but it'll be really feeble. It won't blow up.

A 12V ballasted / 6V unballasted coil can only be used to replace a 12V unballasted coil if the ballast resistor is fitted as well. Without the resistor it'll blow up.

A 12V unballasted coil usually has a primary resistance somewhere in the region of 3 ohms. A 12V ballasted / 6V unballasted coil usually has a primary resistance somewhere in the region of 1.5 ohms.

[arcturus]

Thanks. The reason I was asking is that I recently changed the coil on my B16b PV 6v. I also fitted a 123 dizy. The coil I changed to was given to me by an acquaintance some time ago who assured me that it was from a 6v system. Everything worked well for some time, about 200km, then I started to experience misfires, occasionally at first and then more and more, especially under load. strangely I could mitigate this by speeding up to about 110kph+
i am now changing to a new regular 6v coil when I get the car back on the road. BTW did the coils fitted (armored cable) have an internal ballast or not?

[Pigeon]

The armoured-cable coils are unballasted.