At 01:38 PM 9/27/2001 +0100, Richard Gosling wrote:
>Daffy seems to have an occasional poor running problem.
><snip>
>
>For info, Daffy is a standard UK 1500 (apart from foam air filters), twin SU
>carbs, standard exhaust, standard points ignition. Ignition recently
>checked and spark is at 10 BTDC dynamic @800 rpm (as it should be), spark
>plugs have biscuity-coloured deposits indicating the mixture, at least most
>of the time, can't be that far off.
One thing that hasn't been suspected is the spark plug wires, cap or rotor.
Richard doesn't mention the age of these items, but I have had cars that
needed them, and have suffered similar symptoms.
When the high voltage secondary circuits of the ignition start to break
down (from heat, age; or moisture) the current path will often
intermittently '"strike out on its own", so to speak. The wires can arc to
one another, the dizzy cap can "track" to earth instead of the rotor, or
the rotor itself can short to the inside of the dizzy.
I have heard several stories that indicate that the quality of currently
available electrical parts can be "wanting". So even if these things are
only a year or so old, I'd be wondering about them.
My 2 cents..
Atwell Haines
'79 Spitfire
Succasunna, NJ USA
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