Tom,
The first step in a proper tune-up/adjustment is to make sure your
butterflies are set exactly the same, and that you are not trying to
compensate their position with the idle adjustment screws. The car
should not run with both idle screws completely backed out. Start by
loosening the pinchbolt on both sides of the butterfly shaft, and
completely close both butterflies. Make sure your idle mixture screws
are backed out completely when you do this. Make sure that when you
tighten each pinchbolt, the pin that opens the butterfly is in
<underline>exactly</underline> the same position. You can do this my
moving it against the butterfly lever until it just makes contact. Make
sure you tighten down each pinchbolt so that the setting won't slip.
Then check by pulling up on the throttle cable that they make contact
at the same moment and move in unison. It is important to be precise
with this first step. Turn in your idle mixture screws one to one and a
half turns, both the same, and start out twelve flats down (2 turns) in
the jets. Adjust everythingin parallel from this point on. As you
change the richness, you'll compensate the idle with the idle mixture
screws. If you do your synchronising from this starting point, you will
bw amazed at the difference it makes. You may have other problems, but
you to <bold><underline>have</underline></bold> to start with this step
or you're just wasting your time.
Let's see what happens after you've done this.
Gerard
At 9:04 AM -0400 5/16/99, Tom Zuchowski wrote:
>Once again, I turn to the all-knowing wisdom of the List. . .
>
>I was doing some tune-up of my 1275 yesterday. The carbs have always
been a
>little odd, but I think they are getting worse:
>
>1) With the idle screws backed all the way out, it idles at about 1200
RPM.
>I run them in a quarter-turn so they won't fall out, and that runs the
idle
>up to about 1500 RPM. It's a nice smooth idle, although it's so high.
>
>2) There is no mixture adjustment on the front carb that won't result
in an
>immediate drop in RPM when I lift the slide with the button. The plugs
look
>pretty good, though. I've tried hitting the gaskets with WD40 and
don't
>notice any change. The float height appears to be within specs.
>
>3) On the other hand, the back carb is pretty close to right when the
>mixture nut is run ALL the way up.
>
>4) Using the colortune system, I think I have the back carb real
close, but
>I don't really know where I am on the front carb since I can run the
mixture
>nut down 3 or 4 turns and not really see a color or slide-lift
difference.
>
>5) The front carb has a plastic float and the back one has a brass
float.
>Should I get matched floats?
>
>I'm guessing that something isn't quite right with each of the carbs.
I
>rebuilt them last year after a 9-year sit in the garage without
running, and
>either I did something wrong or else there is something loose or
gummed up
>that I missed, perhaps. The car starts well and runs well, although it
has a
>real tendency to run-on after switch-off.
>
>I would be most grateful for any helpful hints. Thanks!!!
>
>Tom Zuchowski
>Clemmons, NC
G G Gerard Chateauvieux
E A
R R pixelsmith@gerardsgarage.com
A A
R G Pixelsmith on Duty
D E
S http://www.gerardsgarage.com
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