Arctic Cat ZR 120 Service Manual page 32

ASSEMBLING
1. Install the nozzle (H) and main jet (G) into the car-
buretor tower.
2. Place the needle jet assembly (F) and the float (E)
into position and secure to the carburetor body
with the float pin (D).
3. Secure the float chamber w/rubber gasket to the
carburetor with the cap screw (C).
4. Install the pilot jet (B).
5. Install the idle fuel adjuster screw (A) and rotate
the screw clockwise until lightly seated; then
rotate the screw counterclockwise the proper num-
ber of rotations as noted during disassembling.
Install the plastic cap.
CAUTION
Do not force the idle fuel adjuster screw when rotating
it clockwise; damage to the screw taper and carbure-
tor orifice may result.
INSTALLING
1. Install the gasket, insulator, and a gasket; then
with the governor rod and spring installed on the
carburetor, place the carburetor into position on
the mounting studs. Install the flanged nuts and
tighten to 96 in.-lb.
2. Install the choke cable and secure the cable with
the jam nuts and pinch screw.
3. Install the fuel supply hose on the carburetor.
4. Place the gasket and air cleaner assembly into
position on the carburetor; then secure with the
flanged nuts and cap screw.
5. Secure the air cleaner cover to the air cleaner with
the screws. Tighten to 96 in.-lb.
6. Turn the gas tank shut-off valve to the OPEN posi-
tion and check the fuel system for leakage.
7. Adjust the carburetor (see ADJUSTING sub-sec-
tion).
ADJUSTING
The carburetor has been calibrated for average riding
conditions; however, altitude, temperature, and general
744-959A
wear may necessitate certain carburetor adjustments.
Since carburetor adjustments critically affect engine per-
formance, three external adjustments can be made on the
carburetor. These are the throttle stop screw, idle fuel
adjuster screw, and throttle cable.
Throttle Stop Screw
This screw controls the seating position of the throttle
valve which in turn determines the proper idle speed.
Rotate the screw clockwise to increase engine idle speed
and counterclockwise to decrease engine idle speed.
Idle Fuel Adjuster Screw
This screw determines the fuel/air mixture for idling. To
adjust, use the following procedure:
1. Start the engine and allow to run at half throttle 5-
10 minutes to warm up.
2. Place the throttle in the idle position; then rotate
the idle fuel adjuster screw/cap in or out within the
adjustment range to obtain smooth low speed per-
formance.
GF318D
0744-921
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