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MG Midget and Sprite Technical - Polarizing

Can someone please remind me how to polarize a new dynamo?

N Rowlatt

An excerpt from the MASC website but I've no idea if it's correct or not.

"to the dynamo (generator), this requires polarising for -ve earth, this can be
accomplished as follows: Remove the brown/green wire from the small "F" (field) spade
terminal. Find a suitable jumper wire and make a momentary connection between this
spade terminal and the live post of the battery, a spark should be seen as the connection is
made (you can do this a few times to be sure it worked if you like). Reconnect the brown/
green wire and start the engine. The ignition light should act as before: On with the
ignition on, off above around 1000 rpm and off when the ignition is off. If the light does
not go out above 1000 rpm then try re-polarising the dynamo again. If the ignition light is
on when the ignition is off then IMMEDIATELY disconnect the battery and check your

frogeye Gary

and here's a link to the whole document
frogeye Gary

Try this link

Make sure the car isnt postive ground or this link could be ...explosive,1055495,page=1


Prop and the Blackhole Midget

Well there you go...usa and uk version

Your quick on the fingers there gary, I guess I better be doing more puppet finger push ups...hahaha

Prop and the Blackhole Midget

Thanks Gary and Prop.

I dimly remember stroking the field terminal with a wire until it sparks, and what I take from your explanations is that it's from the non-earthed battery terminal - which in this case (+ve earth)- will be the negative pole.

Thanks again.

N Rowlatt

there's a recent John Twist video on YouTube (and one much further back) on the dynamo and polarizing it
Nigel Atkins

from the old vid - spark between A and F on the control box see vid -
Nigel Atkins

This thread was discussed between 12/06/2013 and 13/06/2013

MG Midget and Sprite Technical index

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