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Ignition wiring problem

I'm tidying up some of the wiring on my 1936/7 Opal and have come up against a problem. My ignition switch is not original but a later version of the Lucas PLC series. The terminals on the back do not include either 'D' or 'F' and consequently, according to my wiring diagram, I have a 'D' wire and an 'F' wire coming from the cutout that need to join the switch but apparently nowhere for them to go!
I'd be grateful of members' expert advice on the solution to this.

Location: Sheffield

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Re: Ignition wiring problem

This is a recurring question and there are previous posts to search for.

Alternatve switches do not cater for summer /winter charge. If all else is present and correct the absent wires result in permanent Summer charge and if tied together somewhere permanent Winter charge (which should not exceed about 8 amps on ammeter with lights off).
An auxillary switch can be added to restore the function, but have to remember to use.

The Cornwall Club article A Charging Refresher and John Cornforths of Dorset Club circuit diagram will likely be very useful.

Location: Auckland, NZ

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Re: Ignition wiring problem

Try "summer charge" for search.

Location: Auckland, NZ

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Re: Ignition wiring problem

Thanks for the prompt reply Bob. Do I understand from your comments that the 'D' wire output from the cutout is only used together with the'F' wire as a means of selecting winter charge? And that the actual current to keep the battery charged comes solely down the 'A' wire. If this is the case, then the mist is starting to clear, since the car already has a small toggle switch which I assume was used for the summer/winter selection. In my ignorance I had assumed that the charging current from the dynamo, not unreasonably, comes down the 'D' wire. Ah well, it has only taken me 60 years since my first Seven to learn that it doesn't!!

Location: Sheffield

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Re: Ignition wiring problem

Hi Chris

You got it.

The D and F wires from dynamo need not extend beyond the cutout.
The Cornforth diag reveals all, altho if unfamiliar with ccts you may have to ponder the rotary switch workings, shown in the 3rd postion side lights on.

All the austin diags and most others keep it all unnecessarily obscure.

Location: Auckland, NZ

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Re: Ignition wiring problem

Er, in stating that the D and F wires need not extend beyond the cutout I meant for basic charging. As apparent from all diags, the D does need to be extended (in thin wire) to the dashboard for the ign light.

If John Cornforth ever reviews his very useful circuit diagram, showing the main current wires thicker would further assist understanding. And I suspect many would appreciate a slightly adjusted version for the RP (not to mention all the others).

Location: Auckland, NZ

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Re: Ignition wiring problem

Thanks Bob for the further comment. I'm glad to say that after your earlier advice I've got all the wiring sorted and the car is now generating a healthy current on both summer and winter charge - activated by a small toggle switch. General relief all round! Many thanks.

Location: Sheffield

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Re: Ignition wiring problem

Hi Chris.

As the Yanks say “’you’re welcome”.

Make sure the charge is not too healthy!
Dismantling the original switches is a challenge. I gather the simplified switches are readily available and a practical alternative, although the much reduced number of terminals puzzles some. (In effect the left side of the switch in the Cornforth diag is absent, and some of the other terminals are not duplicated or ommitted).
Curiously the likes of the Ford 8Y did not offer the summer charge option, despite being more likely to be used for long drives.
(I could have answered the original enquiry immediately but waited for 60 others to waste their time and pass over so I would not be accused again of trolling.)

A 3 watt stop light alongside another 3watt is near undiscernible even on a dark night. Considering the extra components involved and introduction of yet another adjustment, I wonder why they bothered.

Nights definitely were darker. On an overnight bus trip through the centre of the NI twenty years ago I was amazed at the degree of lighting in the small hours. Many minor junctions are now floodlit. In the 1950s the small "villages” had just occasional incandescent lamps but now fluorescents and street lighting everywhere.

Location: Auckland, NZ

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Re: Ignition wiring problem

Oops, those last comments attached to wrong post and I cant shift.

Location: Auckland, NZ

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