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 Electrical Problem

 Created by: Coopers66
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 Posted: Apr 26, 2020 06:24AM
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John, before you ASSUME anything, check the wires on the coil. If it's Positive Ground the +CB side will be connected to the distributor. If Negative Ground the -SW side will be connected to the distributor. Don't just hook up the battery as you ASSuME what the polarity of the car. Smoke is hard to put back in the wires once you let it out.

"Retired:  No Job, No Money, Wife and I!  Will travel anywhere for Minis"

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 Posted: Apr 21, 2020 03:54PM
 Edited:  Apr 21, 2020 03:59PM
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US
I found these redrawn diagrams on TMF a bit easier to read than the Haynes
//www.theminiforum.co.uk/forums/topic/324929-wire-diagrams-redrawn/?hl=%2Bheadlight+%2Bswitch

This section on TMF is also very helpful
//www.theminiforum.co.uk/forums/forum/253-electrical/

These guys have the correct color wire to make repairs, MM have full harnesses.
https://www.britishwiring.com/
 

You may need to copy and paste the links.....

 

 

 Posted: Apr 21, 2020 04:14AM
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Thanks Onetim and Dklawson: Just check the cables and it is a negative ground. At least I know what wiring diagram to follow. The link to ground conversion was interesting.

 Posted: Apr 20, 2020 03:38PM
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Unless you have a very compelling reason to have positive ground, convert the car to negative ground following the instructions in the link below.
Link to Mini Mania Tech Article on Ground Conversion.

Doug L.
 Posted: Apr 20, 2020 03:13PM
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If you can locate the old battery connection cables, and if the short cable has the smaller battery post lug of the two, it was negative ground. Or battery’s have a bit larger positive post than the negative one. There may be better ways to tell, but this comes to mind.

 Posted: Apr 20, 2020 01:58PM
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Thanks for the reply Onetim. I have the Haynes manual (1959-1978) and all the diagrams are negative ground. Now here is the kicker, I also have the Autobooks manual (1961-1972) and their diagrams all show positive ground. And the one diagram I was using (1964-1967), enlarged it from some book so I could see it, shows positive ground. I’ll go with your thought and do the negative ground until something happens :)

 Posted: Apr 20, 2020 09:36AM
 Edited:  Apr 20, 2020 09:37AM
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By 1966 it should be negative ground, purchase the Hanes manual that covers you year mini, it will have wiring diagrams so at least you can see how it’s supposed to be wired. A Radford will have some additional stuff, but all of it extra to what’s needed to get the car running driving.-

 Posted: Apr 20, 2020 08:24AM
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Have a couple of questions about wiring. First, car has been down for many years and now retired, I am finally getting it together. It is a 66 Cooper, badged as a Radford, with a 1275cc, originally a 998cc . Do not have a battery in it for that many years, how do I know if it is + ground or – ground? Next, the car has had a lot of wiring changes and was working on the driving lights, but the wiring was not completely installed when i bought the car. A wire goes from the light to the switch and the switch has a green wire which went to ground. Is the second wire at the light, live and go to the fuse to get juice? Thanks