Richard:
The "lift the air valve" test is insensitive if their are vacuum
leaks,
so this is probably why you had poor luck with it.
Looking at the color of your spark plugs after a brief drive
(engine
fully warmed up, choke off of course) is another good method. The spark
plug
tip and ground electrode should be a uniform tan color, about the color
of
corrugated cardboard. If it is sooty black at all, you are too rich.
If it has whitish spots, or is white or nearly white, you are too lean.
If
you cannot achieve a uniform tan color, you have other issues (vacuum
leak?)
that you must correct before you try again.
For the initial startup, set the needle to the center of its
travel
(needle shank is even with the bottom of the air valve).
Your burbling symptom sounds like your dashpots are low on oil,
or
you have a leaking vacuum diaphragm. IMHO, it is unlikely to be related
to
mixture.
Vance
-----Original Message-----
From: owner-6pack@autox.team.net [mailto:owner-6pack@autox.team.net] On
Behalf Of richard.r.olson@faa.gov
Sent: April 11, 2005 10:11 AM
To: 6pack@autox.team.net
Subject: Another A/F mixture question
I'll ask the question here, everything else is just background:
Is there any way, after a ZS carb rebuild, to tell if the A/F mixture is
'good' without using a $$$ commercial tester or building your own ?
I loaned out my Bentleys, so I forget if there's a procedure to blind
set
the mixture prior to installing rebuilt carbs. And I've tried the 'lift
the air valve and listen to the idle' but results were inconclusive.
<snip>
OK, I'll ask another question: Could this condition be related to too
rich
mixture? Which brings me back to my original question at the top of the
post......
TIA
Rick Olson
1972 - CC78827U/5 <- no overdrive here :-)
Pics: community.webshots.com/user/nosto53
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