Alternator doesn't initially provide charge.

[Tonybolony]

I agree with Error about checking belt tension (though if this was the issue, surely you would have heard the belt squealing?), but i'm sure there are plenty of us here who remember the 70's and 80's when virtually anything with a Lucas ACR alternator had exactly the same characteristic (ie after starting- hot or cold- a blip of the throttle (maybe 1500rpm) would kick the alternator in, and not only would the light go out, but you could hear the engine note change with the alternator loading).
I know things have changed just a bit since then, but if a throttle blip is all that's needed, is there an actual fault?

(Just a thought- has the alternator been changed at some time, along with the pulley? What's the diameter of the pulley? If it's larger than the original one.........)

[quattrito]

Hey,

I have quite common problem. The object is 2.3 20V 7A engine.

I turn the ignition key, car fires up, and there is no charging I can see the same ratios in Voltmeter, a bit before 12V, with or without engine running. Then engine won't take rpm's and start to struggle even dies sometimes as I push the gas pedal it starts to rattle and dies most of the time. As I push the pedal you can hear that cylinders ain't working, like there wouldn't be enough spark for all pots. Sometimes it fires up, easily gas up and then car charges as it should and everything is fine. Belt is new, alternator has been changed, problem stays.

[Tonybolony]

Belt is new, alternator has been changed, problem stays.[/QUOTE]

Is the pulley any larger than the original one, or did you re-use the original?

[quattrito]

Pulley and alternator both are from 7A. Pulley I re-used.

[gnutz2]

I've always had this on my 3B and it's not the brushes, belt or voltage regulator as they have all been changed. gutz2 is there something to test to prove it could be the exciter wire/voltage? Mine is definately connected to the stud on my alternator. I may have changed the dash bulb though and never checked what the wattage of the bulb!

You can check the exciter wire has voltage with a voltmeter, alternatively with a small peice of wire you could short the two terminals on the alternator which would bring the alternator in to life (assuming it wasn't charging beforehand).

[quattrito]

In what moment it should show voltage checking with voltmeter?

[SteveH]

You can check the exciter wire has voltage with a voltmeter, alternatively with a small peice of wire you could short the two terminals on the alternator which would bring the alternator in to life (assuming it wasn't charging beforehand).

Thanks. So the wire should go live with 12 volts on first key turn before you crank the car? I assume it goes off afer the charging circuit has kicked in or the key position changes??

[gnutz2]

I'm pretty sure it needs a switched 12v, only when the ignition is on. That's what most alternators need, and how I run mine but I have a Japanese alternator.

Someone with a wiring diagram could assist?