I have a Morris 1300 engine that has an 1- 1/2" carby , it has the same needle as yours .
I'm assuming that it is an original carby .

my money is on the coil or the condensor being the problem
, either one will do what you`re saying

& with the mixture needle thing, the ADF is a swung (self centering/bias needle)
the other 2 are the fixed needle type,,, so if you wanted to play with fixed needles going into swung-needle type carbs you can buy the fixed needle "Adaptor",,, but i really dont think that the needle is your problem

throw a coil or &/or a condensor at the thing ,they`re both easy & cheap to do... & just check that the earth lead is attached to the base-plate & body of the distributor while you`re at it.

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No offence intended here but--> anyone writing a book about minis 30 years ago may not have experienced such worn or stuffed-with components as we are finding these days.

You should put your heart & soul into everything you do.

Sorted.....I decided, with your help, that the carby would not be the problem. Therefore, concentrate on the 'electrics'.
I changed one thing at a time and if the problem was still present, then obviously, that wasnt the hassle.....condensor, points, coil, LT wire from the coil to the points, dist cap, rotor button, one spark plug at a time and there it is....one faulty spark plug.
Anyway, all now ok. Happy again

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Rod
http://smg.photobucket.com/albums/v607/Rodney/

Glad to here it's sorted out mate!
Those pesky spark plugs!

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I have an Addiction just not the time.......
1966 Morris Mini Deluxe http://www.ausmini.com/forums/viewtopic.php?t=80459
1968 Morris 1100 viewtopic.php?f=3&t=101555

Yep.....should have started with the easiest bit

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Rod
http://smg.photobucket.com/albums/v607/Rodney/

Good to hear Ribena is running fine rodney.

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