Coil polarity

[ardee_selby]

Randys' current thread has prompted this question...

After converting to -ve earth, and subsequently fitting Lumenition, I also fitted a new coil.

I got confused with different coil markings (+ / -) and (SW / CB) and how to get correct coil polarity. Don't know if I ever got it right or whether it really matters anyway

Still not totally clear on this...could someone remind/clarify it for me.

[types26/36]

I have always lived by this rule:
What ever ground/earth the vehicle is then that is the coil to distributor side of the coil.
i.e.. if the vehicle is negative ground ....the negative side of the coil (-) is to the distributor.
if the vehicle is positive ground then the (+) is connected to the distributor.
CB means contact breaker.
SW means ign. switch.

[oldelanman]

If it's a coil which is marked CB and SW and was made for a +ve earth you should connect it the other way round when fitting to a -ve earth system ie CB to ignition switch and SW to distributor. According to the attached article it doesn't really matter but you get a slightly stronger spark if it is connected the right way round. There are also a couple of tests you can do to check if it's correctly connected.

http://mgaguru.com/mgtech/ignition/ig104.htm

Regards,

[ardee_selby]

Brian/Roger,

Thank you both. Yes of course...it's all come back to me now!

Randys' thread raised the issue of marrying coil spec to his ignitor...never worried about that in the case of Lumenition. But it brought back memories of when I was sorting out car polarity/correct tacho operation/fitting Lumenition/updating coil etc etc.

Having "sorted" it...this v.old post told the follow-up story!

elan-archive-f16/dangerous-tacho-bounce-was-electrics-t5383.html?hilit= tacho bounce

(FAO Roger...PM is in progress)