Classic cars forum & vehicle restoration.

[john-saab]

Does anyone have a wiring diagram for a 1964 MG Midget..i need to know where the wires from the starter switch go..someone has been playing with a friends car and mucked everything up.
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Rust Junky & oil addict.

[pigtin]

Have been looking at the diagram in my 'Autobooks' workshop manual.
The diagram for Midgets, up to 67, is so small it's almost impossible to read, let alone transmit.

It seems there are three connections on the switch:

1. Is a white that should go to the starter solenoid.

2. It is difficult to make out. There are three white wires. one is shown to go to a push-on connector and from there to the petrol pump and fuse box. The other two seem to go to the tachometer. As far as I can make out: one to power it and the other to the illumination lamp?

3. Brown/blue to A1 on the regulator.

Don.

It is a godawful diagram and I hope this is enough info to get you out of trouble.
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Due to the onset of my mid eighties I'm no longer sprightly and rarely seen in my Austin special. I have written a book though. https://amzn.eu/d/7rwRRqL

[47Jag]

John,

You should have a Brown, a White and a White/Red tracer. Brown is the feed. White is the ignition (probably to the A3 terminal on the fuse box) and the White/red tracer goes to the solenoid. These are standard Lucas colour codes. Any other colours let us know and we can tell you what they should be for.

Art

[Nic Jarman]

Does this help?


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1936 Morris 8 Series 1
1973 MGB roadster
1977 MG Midget 1500
Dax Rush

[pigtin]

There would seem to be a degree of inconsistency in the diagrams printed in various books. Could it be that the manufacturer changed the wiring during the production run of each model. The book I have definitely shows a three terminal switch. Seems, from the above diagram, some of them were fitted with a seperate starter switch. I'm confused now.
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Due to the onset of my mid eighties I'm no longer sprightly and rarely seen in my Austin special. I have written a book though. https://amzn.eu/d/7rwRRqL

[Phil - Nottingham]

The diagram only shows a separate mechanical direct pull starter solenoid (4) - if an electric operated switic or a combined ignition/switch is required then another White/red cable goes from starter solenoid (4) to the extra ignition switch terminal.

Most car wiring diagrams contain errors and inaccuracies and few were updated for minor production changes as basic auto-electrics were assumed to be held by approved service garages etc.

Find out which terminal of the ignition switch is only live when in Start position(often marked 1) and that should run to starter solenoid.

BMC/BL used standard Lucas colours and White cables are always unfused main Ignition circuits with coloured tracers going to other components after junctions/switches.

Brown is main battery unfused, Purple is battery fused accessories (A1/A2) and Green are ignition fused accessories (A3/A4) Light green is via the insturment voltage stabiliser. (not A2 as I had before!)

Red = sidelights, Blue = Headlights

It was all very logical as long as PO's had not messed around with it
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Rover P2
Rover P4
Rover P5 & P5B
Land Rover S2 & S3
Morris Mini Traveller Mk2

[Nic Jarman]

In my rush I thought 44 was 4A ( a coil for the solenoid ) and did not bother to look any farther, I must put my glasses on.
There are a lot of different diagrams so I will post another that has got a solenoid.
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1936 Morris 8 Series 1
1973 MGB roadster
1977 MG Midget 1500
Dax Rush

[Jim.Walker]

Phil, I would question your definition of Purple wires.
I have always understood that that purple signifies a live wire where the component precedes the switch in the circuit. A good example is often purple to horns (usually from the fuse box) where the horn button (switch) earths the circuit. The return wire from horn to button would (properly) be purple with a black tracer to signify it was live, but going to earth via a switch. The switch earth should of course be black.
The basic Lucas colour coding is a good thing to memorise for any classic car owner with that system. Especially useful when stranded at the roadside wondering which wire goes where. Whatever kind of car you have the manufacturer will use coded connections, but there are French systems, Japanese systems,..............
Unfortunately, vehicle manufacturers did not always stick rigidly to the rules and confusing differences can be found in many wiring diagrams. Knowing the tracer application is also very useful unless some uninformed moron has mixed up wires. For example; blue with red tracer is dipped beam headlamp and blue with white tracer is main beam, but I have often found them reversed.
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Quote from my late Dad:- You only need a woman and a car and you have all the problems you
are ever likely to want". Computers had not been invented then!

[Nic Jarman]

Phil, I would question your use of the word accessories.
In the MGB 70/71 wiring diagrams the purple is used as a feed wire from the fusebox - not through the ignition - to the horns, the courtesy light, the boot light and just to spoil the party, it feeds to the light switch. This is post 1967.
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1936 Morris 8 Series 1
1973 MGB roadster
1977 MG Midget 1500
Dax Rush

[Jim.Walker]

Nic, provided the "light" you mention is the interior light I think you have just supported my observation. All the items you mention are typically fed with power directly and earthed though some kind of switch.
_________________
Quote from my late Dad:- You only need a woman and a car and you have all the problems you
are ever likely to want". Computers had not been invented then!

[Nic Jarman]

No, it feeds the main lighting switch so it is not components that are switched to earth - sorry!
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1936 Morris 8 Series 1
1973 MGB roadster
1977 MG Midget 1500
Dax Rush

[Jim.Walker]

Well Nic, at least you have supported my other observation that all manufacturers don't follow the system to the letter!
Jim.
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Quote from my late Dad:- You only need a woman and a car and you have all the problems you
are ever likely to want". Computers had not been invented then!

[Phil - Nottingham]

By all means question it but this is the Lucas logic:-

Accessories which are fused and fed with or without ignition on are Purple (on post war Lucas wiring) - Brown is direct unfused battery.

A1/A2 Terminal/Fuse = Accessories direct battery fed ie not through ignition swithch

A3/A4 = Accessories via Ignition switch.

Accessories = any equipment which is not engine/road lighting related.

A odd number are before fuse evens after - I have corrected this on athe previous posting

See this
http://www.dimebank.com/LucasColours.html

There are others on here too

mnayfacturers did vary colours and so did component manyfacturers.

Lucas column lighting switch should have a purple BATTERY fused cable for the headlamp flasher + a Blue one for the headlights from the main lighting switch. there will also be a Ble/white for main beam and Blue/Red for dip + others depending on what else it controls eg horn


Earthed return switching will have main colour eg Brown/Purple/Green/white + black tracer to switch - then switch may have a black earth cable or just rely on switching
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Rover P2
Rover P4
Rover P5 & P5B
Land Rover S2 & S3
Morris Mini Traveller Mk2