>Adrian:
Did you get Barney's suggestion to check the clamps on the pipe for the
carbs??<
Yes, that was a good one. I checked them and they are OK
Update: The engine vacuum measures a constant 18" at about 1000rpm.
I assume that means the engine is in a fairly decent shape.
I tried setting the mixture on the carbs again, as the engine is obviousl=
y
running weak. The Haynes book says to use the adjusting nut to raise the=
jet so that it is level with the bridge. Then unscrew the nut (thus
lowering the jet) by 12 flats (ie two turns down). Well, that produced a=
very rich mixture with black smoke coming out of the exhaust. I raised t=
he
jets by 6 flats but still got black smoke. So I rased them an additional=
3
flats. No black smoke so I cleaned the plugs and took it for a test
drive. Still the same problem - backfiring, no power over 3000rpm. =
Checked the plugs and they were sooty.
This I don't understand. Exhaust backfire =3D lean, sooty plugs =3D rich=
=2E
Could it be that the sooty plugs are from incomplete combustion, due to,
say, an ignition fault.
Oh yeah, I tried using the strobe and reving the engine, as suggested. T=
he
number of flashes increased as expected and there did not seem to be any
misses. This was on #1 plug, maybe I should do all the others tomorrow. =
I
happened to shine the strobe down the carb throat and saw many small fuel=
droplets on the bridge kind of dancing around - this was at an engine spe=
ed
of about 2000rpm. This was rather unexpected - wouldn't all the fuel be
sucked right into the manifold and into the cylinders? This was before I=
messed about with the mixture and when the jets were only 1 flat down fro=
m
the the bridge ie when you would expect a lean mixture, if you see what I=
mean.
Thanks for the post, I'll let you know what happens next
=
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