Morning. I bought the above ruby some time ago and although it was a runner, the wiring on the charging system had burned out. I had the dynamo and cutout/regulator checked, then I bought and fitted a new loom, making sure that all the new wires corresponded with the old wiring colourwise and in accordance with the wiring diagram. All the lights work ok, the ignition light turns on and the engine starts. However the ignition light doesn't go out and the engine keeps running when I turn the ignition off. There is also a buzzing noise from the cut out when the ignition it turned on. I really need an auto electrician, or someone who is familiar with the wiring of the charging system to sort this out for me. If anyone can offer any suggestions I would be most grateful.
Many thanks Rob.

Location: Sheffield ( Worrall )

Hi Rob,
the 'ignition light' isn't connected to the ignition circuit per se, it is in fact part of the charging circuit and only goes out when the output from the dynamo reaches the required voltage to cause the cut out to 'pull in', transfering the voltage to the battery instead of the warning light.

So to state the obvious it would seem you either have incorrect wiring, a faulty switch or a fault in the charging system fault - eg dynamo or cutout.
It is possible to do some tests using a 6 volt bulb and 'longish flying' leads off the bulb to test where voltage is present, however, my preference is for a multi-meter with a buzzer if possible, to check what connects to where and how much voltage.

I don't like the fact that the cutout is buzzing and I suspect a problem with wiring here and /or there is a problem whereby the ignition has bypassed the switch or there is a short circuit defect within the switch itself.

Try these links for helpful info.

http://www.austin7.org/Technical%20Articles/PLC%20Switch%201/

http://www.austin7.org/Technical%20Articles/PLC%20Switch%202/

http://www.austinsevenownersclub.com/forum/viewtopic.php?t=751

http://www.da7c.co.uk/technical_torque_articles/technical_torque_HOME_PAGE.htm

http://www.austin7.org/Technical%20Articles/


Hopefully a fellow enthusiast local to you will come forward and give assistance.
Steve V.

Location: Polegate, East Sussex, United Kingdom

The various charging circuits and operation are very simple but selected Club publications are about the only documentation that explain.

The dynamo and cutout are precious items so caution is necessary.

Damage can result if the generating dynamo is not connected to the battery, and ditto if the non generating dynamo is!The cutout must not be operated with the engine stopped or dyanmo otherwise not generating.If it becomes operated by fiddling etc and sticks, disconnect battery.

Dynamo output should not be increased much beyond that reqd to meet original headlamp load ie 2x 18w, about 8-10 amps charge on ammeter with lights off.

Location: Auckland, NZ

Many thanks for the above replies, they underline the dangers of getting it wrong and possibly doing damage. I think I will leave it to someone who knows what they are doing. I just need to find a local auto electrician who is capable of doing it. Most of them now just want to plug a computer into a car. If anyone knows of an auto electrician local to me who is familiar with the charging system on the ruby I would be grateful for a contact. Cheers. Rob

Location: Sheffield

Present day auto electricians do not understand Austin Seven electrics like the one who changed the PLC switch on a car locally and put one wire in the incorrect terminal. Everything worked except the owner couldn't switch the engine off, the problem was a bit of a head scratcher because whoever had rewired the car had used only black wires all done up in a nice harness. I suggest you contact your local club to find an owner experienced in electrics or a retired auto electricians.

Dave Wortley isn't far from you. (Stannington)

Many thanks for the advice. Cheers. Rob

Location: Sheffield

Most of the Austin publications and contemporary derived books show wiring rather than circuit diagrams and this makes understanding of the working more difficult, esp if any non standard parts. The John Cornforth general diagram from Dorset Club and the last diagram and notes from Charging Refresher of Cornwall Club may be useful to yourself and any modern electrician.

The latest mention of a 3 brush system I have found in any car textbook is 1960s so many will not have heard of.

if car has been converted to 12v, two brush, mechanical or electronic voltage control etc and no details it all gets more involved.

(If the electrician is puzzled by the exact purpose of the field fuze, so am I.)

Location: Auckland, NZ

Thanks Bob, I'll get in touch with Dorset and Cornwall. Cheers. Rob

Location: Sheffield

Thanks Jim.
Cheers Rob

Location: Sheffield ( Worrall )