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Dumb Late Night Question

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tony barnhill

tony barnhill

Great Pumpkin - R.I.P
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Okay - the wiring diagram for my '63 MkI Midget shows "SW" & "CB" as the terminals on the coil - but my old & new coils only have "+" & "-".....its late on Friday night...I'm tired & angry...which is which?

Is "SW" "+" or "-"?
 
The ignition switch lead should go to the SW post of the coil, which if it is a negative ground car will be +. The CB is to the contact breakers in the distributor or - in todays terminology.

Now hopefully, you've already gone to bed and you will install the wiring to the coil in the morning after a good night's sleep.

Aloha(It's only 20 to 7 here in paradise).
 
On a '63 it came as positive earth, so SW would be a minus sign on that setup. If the polarity is reversed then Ron's setup would apply.


Just some pot stirring... :devilgrin:
 
In reality it makes no difference. It will run just fine either way.
 
We've had this discussion before, and I agree that it will run either way. However, I suspect it works better if it is wired according to the markings.
 
they do indeed run if bacwards and run BETTER if the polarity is correct.. you only get about 1/2 the voltage if its backward... have a look at a wiring diagram and you'll see why this is so...
 
OK...."SW" = "-"...that's the weay I'll hook it up (if I ever get the correct wiring harness!)
 
My point was not to panic, both will work just fine.
 
Understood, Jack - I just wanted to 'get it right'....plus, I was real tired last night!
 
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