In addition to Barney's explanation, the colour of the wires is as follows:
>From the switch to an in-line fuse - slate (grey).
>From the in-line fuse to the valve - slate/pink.
>From the valve to the oil-pressure switch - slate/yellow.
As a matter of interest as the (North American) cars came out of the factory
this is the *only* way of switching off the engine because Abingdon made a
design error when the ignition relay was added. If there is anything wrong
with the anti-run-on valve circuitry or emissions plumbing the engine
continues to run normally (not the shuddering, rocking type of running on
that the valve was designed to prevent). UK cars never suffered from this
problem, they didn't have the emissions plumbing and anti-run-on valve, so
the design defect was discovered and corrected on those cars, but not
followed through to North American models, for some reason.
----- Original Message -----
From: Bud Krueger <firstname.lastname@example.org>
To: MG List <email@example.com>
Sent: Sunday, April 01, 2001 4:02 AM
Subject: Anti run-on valve circuit
> Hi folks,
> Can anyone lead me to a site with a good technical description of the
> operation of the anti run-on valve circuit? TIA.
/// firstname.lastname@example.org mailing list
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