Edelbrock 1400 - Manual (Page 3)

©2010 Edelbrock LLC
Brochure #63-0443
Part #1400
Rev. 6/10 - AJ/mc
Page 3 of 5
IDLE MIXTURE
The Edelbrock Performer Series carburetor has conventional Idle Mixture
Screws (IMS) that provide a leaner A/F when turned clockwise and richer
A/F when turned counter clockwise. The idle air flow is controlled by a
conventional screw that opens the Primary Throttles. The following
procedure should be used to set the idle mixture and speeds:
1. Fully warm engine and ensure choke is fully open.
2. Air cleaner in place.
3. Set desired speed with the air screw.
4. Adjust the IMS on ONE side to get the maximum possible RPM. Do
not go rich beyond the maximum speed point.
5. If the above changed the idle speed more than 40 RPM, then
re-adjust the speed.
6. Adjust the side OPPOSITE of that in Step 4 to get maximum RPM.
7. Reset the speed.
8. Carefully trim each IMS to again get the maximum idle RPM.
9. Go leaner just enough to get a 20 RPM drop in speed.
10. Reset the speed to the desired RPM.
11. This is a Lean-Best Idle Set. Setting richer than this will not
improve idle quality or performance, but could tend to foul spark
plugs.
WINTER FUEL IDLE SETS
During the winter months (in most parts of the country) the local fuel will
be a “winter” blend that is very volatile, as an assist to cold-engine
starting and driveability during warm-up. However, the high volatility has
the disadvantage of allowing excessive vaporization of the fuel if the
vehicle is operated in a heated area such as a garage. This can result in
problems in the idle-set procedures since the carburetor’s internal vents
will allow this excess vapor to be drawn into the throats and enrichen the
mixture. The idle will be erratic and not seem to be able to hold a set.
To resolve this type of problem, it is advisable to perform the final
settings outdoors after the vehicle has been stabilized with a drive of
several miles.
CALIBRATING THE ACCELERATOR PUMP
If you encounter any hesitations or stumbles that do not seem to be
related to the basic metering or have not responded to changes in the
basic metering, move the pump drive link to one of the holes closer to
the carburetor body. This will increase the stroke length of the plunger
and result in more pump delivery.
FLOAT ADJUSTMENT
To properly adjust the floats in the EPS carburetor, two procedures must
be followed. First, the metering rod/power piston assemblies should be
removed from the top of the carb airhorn. Next, remove the accelerator
pump connecting rod and the choke connec-ting rod. After removing all
the airhorn retaining screws, turn the airhorn upside down with the
gasket in place
(See Figure 3). Use a scale, or a 7/16" drill bit (as
shown) to mea-sure the float level. There should be 7/16" between the
air-horn gasket and the top of the outer end of the float. To adjust the
float level, bend the float lever until the recommended level is attained.
DO NOT press the needle into the seat when adjusting the float lever.
Next, you should check the float drop
(See Figure 4). Hold the airhorn
upright and let the floats hang down. There should be 1-1/4" ± 1/4"
between the airhorn gasket and the top of the outer end of the float. To
adjust the float drop, bend the tab on the back until the recommended
float drop is attained.
3. Connect all throttle and transmission linkages and throttle return
springs.
CAUTION: At this point, make sure all throttle and transmission
linkages operate smoothly from idle to wide open throttle (WOT)
and check return springs for proper pressure.
4. Connect all vacuum hoses to their proper location on carburetor
(See Figure 1). Replace hoses that appear brittle or cracked.
5. Connect fuel line to carburetor (See Figure 1). Avoid contact with
any sharp edges or areas of extreme heat. For best results, use
Edelbrock in-line fuel filter #8873 and fuel line kit #8135.
6. Install new air horn gasket and air cleaner stud (supplied). Install
air cleaner making sure it does not contact linkage or fuel line and
has proper hood clearance. Extremely low profile air cleaners will
not fit without #8092 (due to choke interference).
7. Trim air cleaner stud to proper length.
8. Re-check all linkage for smooth throttle operation.
9. Start the engine and check for any possible fuel or vacuum leaks.
CAUTION: Be alert to carburetor flooding. Flooding can be caused
by dirt, small particles of hose cuttings, floats and inlet needles
which have settled during shipping. When the fuel pump is turned
on or when the engine is first started, watch closely for signs of
flooding. If flooding occurs turn engine off immediately and lightly
tap on the side of the carburetor that is flooding, in the rear needle
and seat area with a rawhide mallet or wooden handle of a
hammer. Start engine and see if flooding continues. If flooding
continues, stop the engine. Clean up any raw gasoline and refer to
the “Adjustments and Troubleshooting” section of the
Instruction Sheet.
WARNING: NEVER POUR FUEL DIRECTLY DOWN THE
CARBURETOR WHEN ATTEMPTING TO START THE ENGINE! THIS
MAY CAUSE A BACKFIRE AND POSSIBLE ENGINE
COMPARTMENT FIRE, RESULTING IN ENGINE OR VEHICLE
DAMAGE, PERSONAL INJURY AND/OR DEATH.
10. With engine at normal operating temperature and choke fully open,
set idle speed and mixture screws. This procedure is outlined in the
Instruction Sheet.
ADJUSTMENTS AND TROUBLESHOOTING
Float Level
(7/16")
Bend Here
Fig. 3