thanks for the many suggestions from this group about my poor idle/engine
producing no power.
The problem, of course, turned out to be something completely different.
I put a timing light on each spark plug wire (sequentially) to make sure
that every cylinder was firing. When I got to No. 4, I noticed that the
light was virtually always-on, instead of flashing regularly. The problem
was that No. 3 and No. 4 wires, were crossed in near proximity to each
other. Even though the wires are brand new (Bosch, from Vic British, part
number for a Toyota 6-cylinder), evidently I was getting some crossfire from
the Lucas sport coil (also brand new), so No. 4 was firing all over the
place.
All I did was reposition the wires, and -- eureka -- the engine is fine!
However, I'm still working to make sure the timing is correct, and many of
the other tips re carburetor woes will come in useful. So thanks to all.
and it's yet another reminder of the timeless diagnostic rule that applies
to most collector cars: "when you're 99 percent sure that it's the
carburetor(s), it's probably the ignition."
--Graham
ps: bought a Jaguar XJ6 on e-bay yesterday and went to pick it up today. a
very nice car, but the headlights don't work, except on flash-to-pass. The
seller (a dealer) has to fix it because the car has to pass inspection -- I
wonder what his reaction will be when he finds out what a Jaguar headlight
switch costs?
-----Original Message-----
From: tr6taylor@webtv.net
To: vinkg@fleishman.com
Cc: 6pack@autox.team.net
Sent: 5/25/02 1:11 PM
Subject: Re: timing and carbs
Graham---While the amount of advance or retard you have dialed into the
ignition timing can affect idle speed, it shouldn't upset the idle and
carb adjustment. Consider that the engine should idle well when the
timing is set at 4 deg. ATDC, and also idle well when the retard is
plugged, and the timing is then around 10 deg. BTDC. Just for a trial,
plug the retard line, and set the advance to 10 deg. with an idle speed
of about 900 rpm, or as close as you can get, with the erratic condition
you have. Then see if the timing advances further, as you feed in more
throttle. At 3000 rpm, the advance should be near 28 on the pulley. If
not, the centrifugal weights and springs need to be looked at, for
correct movement. (They may only need cleaning and a little oil)
Can you hear any 'arcing' coming from under the rotor cap during these
misfires?
Also check the carb diaphragms for integrety, if you haven't already
done so.
Dick Taylor
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