407 Coil Failure

[Julian Caples]

The 407 does have a relay

you must have either a relay or a diode in the feed from the starter solenoid or you will have power fed (at about 8-9v) from the coil feed back to the starter after the engine has been started - this is unlikely to be a good thing

the other method for bypassing the ballast during starting is a separate circuit independently switched from the ignition key (i.e. when turning the key to the 'start' position, it activates two independent circuits - one for the starter solenoid and another that bypasses the ballast)

John's chevy installation must have a diode or relay in the solenoid (i.e. specific terminal for a ballast bypass that does not allow feed back to the solenoid)

regards

Julian

[Nick Challacombe]

Barrie,

My 407 wiring diagram clearly shows a ballast relay between the coil and the starter. A white wire when built goes from C1 on the ballast relay, through the fuse and ignition switch to ignition warning light and then the control box. A white and red wire leave the ballast relay from W2 and goes straight to the starter. From the ignition coil a white and yellow wire join with a white wire at a ballast resistance where it leaves as a white/yellow wire onto C2 of the ballast relay
I have a spare Instruction Manual and a spare, Spares Handbook should your pal wish to purchase them.
I do not want to confuse but the wiring diagram I believe is also available on the BOC web site.
A hand book is always a good thing to have. I even have a Brand New Instruction Manual and Spares Handbook, never been in a car but in my archive.