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MG MGA - generator again

Hi all,
Here I am again.A few days ago I asked for some help to fix my generator problem.
So what I did untill now.
I magnetised(again) the generator by connecting the small terminal to the starter switch hot side,thats +12V because I have a -ground system.
This afternoon I took the generator out again and connected the two terminals with a piece of wire.Next I connected +12V to the terminals and connected the generator ground to the - battery terminal.the spindle started to turn as an electric motor.So far so good.
Next,the generator back in the car.The two terminals connected by a piece of wire and a voltmeter connected to the wire and car ground(-).When I started the engine the generator produced no voltage.
So I think I am missing something.As the generator acts as a motor this indicates that the generator is OK.But why does the generator produces no voltage when he is in the car and driven by the engine?
More strange is that at this point the regulator has nothing to do with all of this.
When I connect the generator as it should and I start the engine the ignition light keeps on burning.When I increase the RPM the ignition light varies a ( very little)bit.
I am doing something wrong but I don't know what.
Help please, I don't know anymore what to do.Any tips/suggestions are more than welcome.

Herman
H. Jorens

Just off the cuff, maybe a bad volt meter with no output reading (switched to wrong setting or connected wrong on he meter). AND also a faulty or mal-adjusted regulator, which is the source of the problem to begin with.
Barney Gaylord

Herman,
Is there any way that you may have painted the mounting, generator body etc. so well that it does not have a good ground when in the car. Yoy could check that by loosening off one of the mounting bolts, slipping a wire between it and the generator and tightening the bolt back up. Then touch an ohm meter to the end of the wire and a point on the generator body where there is no paint (may have to scratch it!) to see if the ground wire is a good ground. If it is good attach the ground wire somewhere on the car that you know is a good ground and try it. The fact that the generator ran when connected to a battery indicates that it should work. Just a thought. I had that problem before, except with the starter. It ran out of the car, but not when in place. It was too much paint causing no ground.

Ralph
Ralph

The voltmeter is OK.
But I have to check if I have a good ground when the dynamo is in the car.It is a new engine, painted in two pack, including the brackets.
Good chance that it is the reason why he does not work.Otherwise I have to check the regulator.
Thanks,
Herman
H. Jorens

This thread was discussed between 01/05/2011 and 02/05/2011

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