Morris Minor Owners Club

Yes - try that - but without the 'extra' wire directly to the battery - at first. If still no charge - then with the engine running - try that wire direct to the battery - to 'bypass' the cut-out in the Volt Regulator box. If you connect it while the engine is not running - it will obviously just try to 'motor' the dynamo. If it now charges - then the problem lies in the cut-out inside the Regulator.
In my experience - a dynamo that 'motors' is a good working dynamo!

I just got a reading and I can now say for sure the dynamo is in good working condition. I suppose this means the old control box might have to be replaced. Is there any way to force the control box to let the current through to see where the problem is? I saw new reproduced control boxes for sale on the internet. Are these any good?

Ok - so remove the 'jumper wires' and try without. If still no charge - try cleaning the contacts in the Reg box - that should work! You can push the cut-ot contacts closed and they should hold closed with good charging - but watch to make sure they open again when the engine is shut down. It's likely the problem lies in the other bobbin - the voltage regulator - which should open and close quickly to control the volts. It is adjustable - see the workshop manual.

I tried cleaning the contacts immediately after I got a sign of life from the dynamo. I also pushed both the cut-out and regulator contacts but everything seems absolutely dead in the control box. While I pushed the contacts the motor was running and a volt meter was connected to the battery and there was no change of voltage.

May be poor contact with the wires going into the control box - worth checking - otherwise - take the control box off and have a look at the underside - may be rotted away with a broken connection. If so - could try patching up but probably better to source another unit - not necessarily a new one ! In the short term - to force a charge - you can rig up your jump wires again - but take care you don't overcharge the battery which produces oxygen and hydrogen - explosive mixture!

I have checked the underside and it looks quite okay but not like new. I replaced the wire from the control box to the starter contact and there was a change. Now the red light won't go out when the motor is started. I suppose that's an improvement since now at least the red light is honestly showing that the battery isn't being charged. Still every part of the voltage regulator keep absolutley still. I have ordered a new control box so hopefully I will be able to get the Moggie running properly within a few days.

Hmmm - 10/10 for perseverance ! Note Barry's excellent wiring diagram at the top of the 'electrical' section ^^^^ - well worth printing it out and keeping a copy in the car. With that in hand - check out all the wiring to see if it has been disrupted by previous owner.

Barry's wiring diagram is really nice. Thanks! After work today I amused myself by replacing the wires connected to the dynamo, to the battery and to earth. The only change is that the Moggie looks like a plate of Spaghetti under the bonnet with all the extra wires. I guess I won't get any closer to the solution of this case until the new control box arrives.

Sometimes it pays off not to give up. I gave it another try today and now everything is working! I noticed the braker points of the cut-out never got in touch with each other. I did some bending and next time I started the motor the contacts started moving. The red light went out but still no charging. Then I adjusted the voltage while I was watching the volt meter and as I turned the screw the voltage went up. I stopped turning the screw when the voltage reached 13,3 Volts. So right now, when idling the meter says 12,5 V and at high RPM's 13,3. The only thing that puzzles me is that when the motor is turned off and I force the cut-out contacts together the stay in contact until I force them to part again. If I don't do anything manually they go apart as soon as the motor is turned off. This Moggie is gonna do a lot of traveling this summer:-) Thank you everybody for your help!

Well done - but just make sure the charge rate is not too high - and it boils the battery! Perfectly normal for the points to stick in if you close them when the engine is not running - as long as they work normally when the engine starts/stops - they will be fine. But do keep an eye on the battery in case it's overcharging. Once the battery is charged up properly - try with the headlights + heater fan running - and decent revs - does it still hold above 12.5 volts ok ??