I need some help please i have a 74 v12 roadster and the wiring diagrams i have do not include the coolant switch on the thermo housing that triggers the solenoid for the air and vacuum advance. the problem I have is as soon as i ground the switch wire it triggers a solenoid and i think that would drain the battery. So I would need the latest wiring diagram if anyone could help. e mail info@bmcmotorworks.com Thank you.
David to have all the information you need a 1974 owners handbook and the wiring chart.
A tip that I’ve used is to have several copies of the wiring diagram, with each copy having the different functions highlighted, such as the one for A/C and ventilation I have one copy where all switches, fuses, fan motors, ventilation fan motors, relays and so on are highlighted with a yellow highlighted pen. It makes it easier to read and use the diagram in trouble shooting situations or when putting things back together.
Dear David,
I also have a 1974 car but all of these items have been removed from the engine bay. From looking at the remains of the harnesses, it looks as though these are green wires so one would expect them to be ignition feed related. I think you’ll need to trace them back individually. The tan coloured US Owners Manual booklet explains how they are all connected and the 1974 Parts Manual shows their interconnection with the vacuum system as seen by the Borg-Warner autobox. If you seek out a very old photo album of mine, you’ll see it all annotated and explained, but read the work “retard” where I have written “advance” in pencil.
You can of course just disconnect various parts of this and plug the relevant holes - all it was ever intended to do was retard the ignition advance under certain circumstances like low coolant temperature, low roadspeed, etc.
kind regards
Marek
This is my drawing, done about 10 years ago with the help of a couple of S3 owners. Its posted on xkedata as a pdf but I have it in the original tiff form and jpg. I’m going to attach the jpg version as tiff may not be familiar to many… but best for archiving. There have been a few small changes to it in the time since it was created, the most notable was the original factory didn’t include the choke warning lamp??? Anyway someone brought it to my attention so I added it. Since I don’t have an S3 if there are corrections I’d be happy to make them. We want/need the most accurate info we can get.
pauls
