Carburetor Set Up and Lean Best Idle Adjustment |
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Base
line Settings Speed Screw 1 to 11/2 turns Mixture Screw 2 turns Your settings with engine running Speed Screw______________ Mixture Screw______________ |
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It is important to follow all linkage and lever
installation instructions. The number one and two reasons for tuning
errors are improper linkage installations and over tightened linkage nut,
causing a binding in linkage assembly. CALIBRATIONS MAY VARY DUE TO REGIONAL FUELS AND STATE OF
ENGINE TUNE AND PERFORMANCE. POOR RUNNING QUALITY DOES NOT MEAN A DEFECT
IN THE CARBURETOR. AN ADVANTAGE OF THE WEBER CARBURETOR IS ITS EASE OF
ADJUSTMENT AND TUNING. SET
UP ADJUSTMENTS Start set up by confirming carb base line settings. Do not
depend on the factory delivered settings. Check them before the carb is
installed. All settings are done with choke disengaged or warmed up so
that the choke is fully opened and disengaged. This is done on automatic
choke carburetors by first opening the choke butterfly by hand and
inserting a wood block or wedge of some kind to hold open while the
linkage is cycled (linkage operated through its full movement ) to clear
the choke cam. (You will hear a metallic click as the cam is released. You
can check the fast Idle screw under the choke assembly to confirm that it
is not in contact with the choke fast idle cam.) Set the Idle stop screw (speed screw see fig 1)
by backing out the Idle speed screw until it is not in contact with
the throttle stop lever. Cycle the linkage again to be sure that the
linkage comes to close without any assistance. (Checking for linkage bind)
Now bring screw back into contact with the lever and continue to
open or screwing in 1 turn no more than 11/2 turns. Set the mixture screw (see Fig 1) by first screwing in
until the screw stops, bottoms out. DO
NOT FORCE OR BIND AS THIS WILL CAUSE DAMAGE TO THE SCREW AND IT’S SEAT
IN THE BODY OF CARBURETOR. Back
out the screw 2 full turns. |
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TUNING
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Simple
Rules for low speed calibration If the mixture screw is more than 2 1/2
turns out turns then the Idle jet is too lean (too Small). When the
mixture screw is less than 11/2 then
the Idle jet is too rich (too large). These assumptions are based on the
fact that the speed screw setting is not opened more than 11/2 turns. If
the speed screw has to be opened 2 or more turns then this is also an
indication of a lean condition usually requiring greater change. At times
it may appear to be showing signs of richness or flooding it is really a
lean condition. See pictures and notes in the tech 2 article supplied in
the kit instructions, view and please understand the need to keep throttle
plate as near to closed as possible so as not to prematurely expose the
transition holes. This is what causes the visible rich condition, and
confirms the need to increase the jet size. JET KITS are available if
needed. EXAMPLE With
the speed screw set at no more than (1 1/2) turns in after contact with
the stop lever; and the best idle occurring with the mixture screw
set at 3 turns from bottom,
indicates the need for a larger Idle jet. Achieving the best idle at under
2 turns indicates the need for a smaller idle jet. The secret to
understanding the critical nature of the carburetor set up and the
advantages of a WEBER over other carburetors is the Idle circuit. Referred
to as the low speed circuit by Weber, this circuit is responsible for 80%
of the driving operation. This is the reason that the Weber should give a
fuel economy improvement over most factory carbs along with significant
performance gains. In the worst case you should not see a
significant fuel economy loss over stock, while improving HP &
Drivability. The Weber Carburetor is a sequentially timed device to the
motor like the distributor. Time taken in the setup will provide more fun
later. If you should need to call REDLINE for technical
assistance we will need to know your final settings to help. Technical
assistance is free for the first 60 days of purchase. Units in service
over 60 days may be assessed a service fee. All charges will be noted up
front after a brief consultation to determine any possible defect. If the
carb is out of the warranty period and no defect is determined we will
estimate the possible cost of tech support or recommend literature
available that may help.
ALL WARRANTIES
ARE HANDLED DIRECTLY THROUGH REDLINE
NOT THE RETAILER. DO NOT SEND PARTS TO MANUFACTURER WITHOUT CALLING FOR
TUNING CONSULTATION AND WARRANTY CONFIRMATION OR INSPECTION RETURN
AUTHORIZATION. PARTS RETURNED WITHOUT AUTHORIZATION NUMBERS
WILL BE REFUSED AND RETURNED FREIGHT COLLECT.
PARTS
RETURNED FOR INSPECTION AND WARRANTY CONSIDERATION AND NOT FOUND TO BE
DEFECTIVE WILL BE CHARGED A MINIMUM INSPECTION AND ADJUSTMENT CHARGE OF
$35.00 AND RETURNED FREIGHT COLLECT. Contact REDLINE at 1 800 733 2277 ex 7457 Monday thru
Friday 8:00 to 5:00 Pacific Standard Time
Non warranty Tech support is on a
fee for services basis with minimum charge
of 35.00 per problem resolution
. With tech support calibration and tuning parts will be available
at discount pricing as
well as access to technical support documents and mailings |
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