body and install the two main body to throttle body
screws and lockwashers.
Care should be exercised in aligning nozzle
tube extensions to receive nozzle tubes.
This will insure a proper fit between the
main body and throttle body and prevent
2. Install the pump link stud, new pump link,
and new pump link cotter or retainer.
weather operation and the inner hole pro
vides a minimum pump discharge for hot
weather. For most driving conditions, the
middle hole should be used.
3. Place a new main body cover gasket in
position on the main body and install the main body
cover to the main body with the four main body
cover screws and lockwashers. On governor
equipped carburetors, fasten the governor vent
tube in position under the proper main body screw.
4. Install the air cleaner anchor screw and
bleeder screen washer.
Three holes in the throttle lever permit
adjustment of the accelerating pump dis
charge. The outer hole provides a maxi
mum pump discharge for extreme cold
Install the fuel filter screen retainer spring,
new filter screen assembly, and fuel inlet fitting
with a new fuel inlet fitting gasket.
Before installing a carburetor, make a visual
inspection of its exterior to be sure the unit has
not been accidentally damaged due to improper
storage or mishandling.
Be sure the carburetor mating surface of the
intake manifold is clean. Then, using a new flange
gasket, secure the carburetor to the intake mani
fold with the four mounting nuts and lockwashers.
Tighten the mounting nuts alternately, a little at
a time, to evenly compress the flange gasket. The
nuts must be drawn down tight to prevent leakage
between the carburetor and manifold. Connect the
distributor vacuum line, the fuel line, and throttle
and choke linkages, making sure there are no worn
or loose connections. Connect the governor air
lines on the truck carburetors.
of "Reassembly - Throttle Body - Governor
Do not seat the idle adjusting needles too
tightly as this will grove the tips of the
needles and prevent a smooth idle. If the
needles become grooved, they must be
discarded and replaced with new ones.
3. Start the engine and allow the olwrA!i~:
temperature to reach normal. Reset the idle slxoed
screw if necessary to obtain an idle rpm fast
enough to prevent stalling during the warm-up
4. With the choke plates wide open and the
fast idle cam on passenger car carburetors in the
position where the idle speed screw contacts the
lowest step of the cam, adjust the idle to the speci
fied rpm with the idle speed screw.
A. Adjusting the Idle
1. Make sure the vehicle is on level ground.
2. Seat idle adjusting needles lightly and
back them off exactly one full turn if there is any
doubt about this having been done during reas
sembly. See Step 3 of "Reassembly - Throttle
Body - Passenger Car Carburetors", or Step 8
5. Set the idle adjusting needles to give the
highest steady manifold vacuum reading, or the
smoothest running and maximum idle speed, if no
vacuum gage is available.
This can be ac com
plished by turning one idle adjusting needle in un
til the engine begins to slow down, then backing
needle off over the "high spot" until it again begins
to slow down. Setting the idle adjusting needle