Snowmobile Arctic Cat (2002 year). Manual - part 57

4-21

4

GF317D

3. Install the fuel supply hose on the carburetor.

4. Place the gasket and air cleaner housing into

position on the carburetor; then install the air

breather hose.

GF316D

A001

5. Place the air cleaner housing and carburetor on the

engine and secure with the flanged nuts and cap

screw.

GF314D

A002

6. Secure the air cleaner end cap to the air cleaner

with the wing nut.

7. Turn the gas tank shut-off valve to the OPEN

position and check the fuel system for leakage.

8. Adjust the carburetors (see appropriate Adjusting

Carburetor in this sub-section).

Installing Carburetor

(VM-Style)

„

NOTE: On twin carburetor models, install the

carburetors using this basic procedure.

1. Place the carburetor into position in the flange and

air-intake silencer boot; then tighten the flange

clamp making sure the carburetor is level. Do not

over-tighten the flange clamp as it will damage the

carburetor flange.

4-22

AH103

„

NOTE: Slide the carburetor into the air-intake

silencer boot; then slide the carburetor into the
flange.

2. Connect the fuel hose to the carburetor inlet

fitting.

3. Thread the brass choke-cable housing into the

carburetor making sure the washer is properly

positioned and tighten securely.

AH099

4. Place the piston valve into position making sure

the full-length groove in the piston valve is aligned

with the pin in the mixing chamber bore.

AH100

5. Secure the mixing body top by tightening the

screw and lock washer making sure the mixing

body top plate is properly positioned.

6. If applicable, connect the safety switch harness to

the main wiring harness.

7. Turn the gas tank shut-off valve to the OPEN

position.

8. Adjust the carburetors (see appropriate Adjusting

Carburetors in this sub-section).

Installing Carburetors

(TM-Style)

1. Prior to installing the carburetors, the carburetor

throttle valves must be checked for

synchronization.

A. With the throttle in the idle position, select a

small drill bit that will just fit under the

cutaway of the fixed throttle valve.

B. Using the same drill bit, check the clearance

under the adjustable throttle valve cutaway. If

clearance is different from the first carburetor

checked, adjust the throttle valve by loosening

the lever ring locking screw; then using an

open-end wrench, rotate the synchronizing nut

in either direction until the clearance is the

same as the first carburetor checked.

0734-445

C. After synchronization has been attained, hold

the synchronizing nut with the open-end

wrench and tighten the lever ring locking

screw.

2. Place the carburetors (with float chamber vent

hoses) in the engine compartment and into the

carburetor boot; then tighten the clamps.

3. Connect the fuel supply hose to the fuel inlet T-

fitting.

4. Connect the throttle cable and choke cables.

5. At this point, there must be free-play gap in the

throttle lever.

4-23

4

733-081C

„

NOTE: If throttle cable free-play is incorrect, the

throttle safety switch will be activated prematurely
and the engine will not start.

„

NOTE: If cable free-play must be corrected, uti-

lize the jam nuts on the throttle cable bracket until
no free-play is attained.

6. Place the air-intake silencer into position in the

engine compartment making sure the carburetors

are properly positioned in the boot and secure with

screws.

7. Place the ignition coil/fuel pump mounting plate

into position on the air-intake silencer and secure

with the machine screw and washer.

AN613D

8. Adjust the carburetors (see appropriate Adjusting

Carburetors in this sub-section).

Adjusting

Carburetor

(BV-Style)

The carburetor has been calibrated for average riding

conditions; however, altitude, temperature, and general

wear may necessitate certain carburetor adjustments.

Since carburetor adjustments critically affect engine

performance, three external adjustments can be made

on the carburetor. These are the idle speed screw, pilot

air screw, and throttle cable.

0735-464

IDLE SPEED SCREW

The idle speed 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.

PILOT AIR SCREW

The pilot air screw determines the fuel/air mixture for

idling. To adjust the pilot air screw, use the following

procedure:

1. Carefully rotate the pilot air screw clockwise until

a light “seating resistance” is felt.

2. Rotate the pilot air screw counterclockwise 1 turn.

3. Start the engine and “fine tune” the pilot air screw

until the engine idles smoothly.

THROTTLE CABLE

The correct throttle cable adjustment is when (with the

engine OFF) the carburetor throttle is completely open

(against its limit) while the throttle lever lightly con-

tacts the handlebar grip. The throttle arm on the carbu-

retor should also contact the speed control screw when

the throttle lever is released.

! CAUTION

DO NOT force the pilot air screw when seating;
damage to the pilot air screw will result.

4-24

To adjust the throttle cable, use the following proce-

dure:

1. Loosen the throttle cable wire binding screw.

0735-459

2. Pull all slack from the throttle cable wire and exert

slight tension on the wire.

3. Tighten the throttle cable wire binding screw.

SPEED CONTROL SCREW

The maximum speed of the snowmobile can be

reduced by adjusting the speed control screw.

To reduce the maximum speed, rotate the speed con-

trol screw clockwise. DO NOT EVER INCREASE

THE MAXIMUM SPEED BEYOND THE ORIGI-

NAL 8 MPH MAXIMUM!

Adjusting

Carburetor(s)

(VM-Style)

ADJUSTING CHOKE CABLE(S)

1. Be sure the ignition switch key is in the OFF

position and the brake lever lock is set.

2. Loosen the jam nut securing the choke cable

adjuster. Rotate the choke cable adjuster

clockwise until it bottoms against the brass

plunger cap.

3. Slowly rotate the choke cable adjuster

counterclockwise while checking the choke lever

for free-play. As soon as all free-play has been

removed from the end of the lever, stop rotating

the adjuster.

4. With free-play removed from the lever, slowly

rotate the choke cable adjuster once again

clockwise while checking the choke cable lever

for free-play. Adjust until 3 mm (1/8 in.) free-play

between front bottom edge of lever and housing is

attained. Securely tighten the adjuster jam nut.

0732-848

5. On twin carburetor models, repeat steps 3 and 4 on

each carburetor.

„

NOTE: On twin carburetor models if a carburetor

choke cable is adjusted too tight, the engine will
only operate on 1 cylinder at idle.

! WARNING

Do not attempt to adjust the throttle cable with the
engine running. Personal injury could result.

! WARNING

DO NOT operate the snowmobile when any compo-
nent in the throttle system is damaged, frayed,
kinked, worn, or improperly adjusted. If the snow-
mobile is operated when the throttle system is not
functioning properly, personal injury could result.

! CAUTION

The air-intake silencer and boots must be in
position whenever the engine is run. If the
silencer is removed and the engine is run, a lean
condition will result. Therefore, DO NOT run the
engine when the air-intake silencer is removed.