Snowmobile Arctic Cat (2008 year). Manual - part 74

 

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Snowmobile Arctic Cat (2008 year). Manual - part 74

 

 

4-12

2. On twin carburetor models after the engine has

been allowed to warm up for 2-3 minutes, adjust

engine idle by first rotating the PTO-side carbure-

tor idle speed screw clockwise until the tachome-

ter reads 1480 RPM.

3. On twin carburetor models, rotate the MAG-side

carburetor idle speed screw clockwise until

tachometer reads 1500 RPM.

AH055

4. On twin carburetor models, rotate the PTO-side

carburetor idle speed screw clockwise until the

tachometer reads slightly above 1500 RPM; then

rotate the idle speed screw counterclockwise to

achieve exact 1500 RPM reading. The piston

valves should now be synchronized and the engine

should idle without holding any throttle pressure.

„NOTE: If the engine has no ignition spark with
the throttle in the idle position but has proper spark
with the throttle lever slightly compressed, the car-
buretor safety switches must be repositioned.

5. Test the throttle control lever by compressing and

releasing it several times. The lever must return to

the idle position quickly and completely.

Throttle Cable

„NOTE: Determine which type of cable is being
replaced and remove and install accordingly.

REMOVING

734-533A

737-544A

1. Loosen the throttle cable adjuster jam nuts.

2. Remove the mixing body tops.

3. Remove the throttle cables from the piston valves.

4. Remove the throttle cables from the mixing body

tops.

5. Remove the handlebar pad and console.

6. Remove the cable ties securing the throttle cable.

7. Remove the throttle cable end from the throttle

lever.

8. Using Throttle Cable Removal Tool, push down

on the throttle cable retaining clip; then remove

the cable from the throttle switch assembly.

„NOTE: On twin carburetor models, it may be
necessary to remove the PTO-side carburetor.

9. Remove the E-ring securing the oil-injection cable

to the control arm. Account for a washer.

10. Loosen the jam nut securing the adjustment cable;

then remove the cable from the oil-injection pump.

INSTALLING

1. Route the throttle cable from the throttle switch

assembly to the carburetors and oil-injection

pump; avoid any sharp bends or moving parts.

! WARNING

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

KEY

1. Retaining Ring

2. Throttle Cable

3. Cable Tie

4. E-Ring

5. Washer

6. Nut

1
2

3

4
5

6

KEY

1. Cable Tie

2. Throttle Cable

3. Jam Nut

4. E-Ring

5. O-Ring

6. Retaining Clip

4

4-13

2. Install the oil-injection adjustment cable on the

oil-injection pump; secure with the jam nuts.

3. Install the oil-injection cable on the control arm;

secure with a washer and E-ring.

„NOTE: Install the PTO-side carburetor if
removed.

4. Install the throttle cable into the throttle switch

assembly making sure it snaps into place.

5. Install the throttle cable end on the throttle lever.

6. Secure the throttle cable to the steering post with

cable ties.

7. Install the handlebar pad and console.

8. Attach the throttle cable to each throttle valve. The

valve must seat in the groove of the throttle cable

end; then thread the throttle cable into each mixing

body top.

9. Install each piston valve and mixing body top on

the carburetor(s). Tighten securely.

10. Adjust the carburetor(s) (see Adjusting Carbure-

tor(s) in this sub-section).

11. Synchronize the oil-injection pump (see Related

Items sub-section).

Choke Cable

„NOTE: Determine which type of cable is being
replaced and remove and install accordingly.

737-490A

736-596A

REMOVING

1. Bend down the lock tabs locking each brass choke

cable housing on each carburetor.

2. Using a 12-mm wrench, remove each brass choke

cable housing from each carburetor. Account for

the lock tab washers.

3. Remove each brass plunger and spring from the

cable end; then remove each brass choke cable

housing.

4. Remove the screws securing the console.

5. Position the choke lever in the middle-choke posi-

tion; then remove the knurled nut securing the

choke lever housing to the console.

725-001A

6. Slide the choke lever housing from the console.

7. Cut any cable ties used to secure the choke cable

and remove the choke cable from the engine com-

partment.

INSTALLING

1. Position the choke lever in the middle-choke posi-

tion; then from the back side of the console, insert

the choke lever housing through the console.

Secure with the knurled nut.

2. Route the choke cable from the console to each

carburetor; avoid any sharp bends or moving parts.

! CAUTION

Compress the throttle control lever to ensure free
movement. If the throttle cable sticks or binds, cor-
rect the problem before starting the engine.

KEY

1. Choke Cable

2. Knurled Nut

3. Choke Lever Kit

KEY

1. Choke Cable

2. Knurled Nut

3. Choke Lever Kit

4-14

3. Install each brass choke cable housing onto the

cable end; then install each spring and brass

plunger.

4. Place the lock tab washer on each brass housing

and insert a choke plunger into each carburetor.

5. Thread each brass choke cable housing into each

carburetor and tighten. Bend the lock tab up to

secure the brass housing. Adjust the choke cable

(see Adjusting Carburetor(s) in this sub-section).

6. Place the console into position and secure with the

screws.

Troubleshooting Fuel 

System

Problem: Carburetor Too Rich (0-1/4 Opening)

Condition

Remedy

1. Choke plunger will not seat

2. Pilot air screw too far in

3. Pilot air passage obstructed — damaged

4. Float/inlet needle obstructed — damaged — adjusted

incorrectly

5. Pilot jet loose

1. Adjust — service — replace choke cable — plunger

assembly

2. Adjust pilot air screw

3. Remove obstruction — replace pilot air screw — carbu-

retor

4. Remove obstruction — replace inlet needle — float —

adjust float tab

5. Tighten pilot jet

Problem: Carburetor Too Rich (1/4-3/4 Opening)

Condition

Remedy

1. Pilot air screw too far in

2. Needle jet — jet needle worn — adjusted incorrectly

— incorrect

3. Pilot air passage obstructed — damaged

4. Pilot jet loose

5. Float/inlet needle obstructed — damaged — adjusted

incorrectly

6. Main jet loose — too large

7. Primary air passage obstructed

1. Adjust pilot air screw

2. Replace needle jet — replace — adjust jet needle E-

clip

3. Remove obstruction — replace pilot air screw —

carburetor

4. Tighten pilot jet

5. Remove obstruction — replace inlet needle — float —

adjust float tab

6. Tighten — replace main jet

7. Remove obstruction

Problem: Carburetor Too Rich (3/4-WOT Opening)

Condition

Remedy

1. Main jet loose — too large

2. Float/inlet needle obstructed — damaged — adjusted

incorrectly

3. Needle jet — jet needle worn — adjusted incorrectly

— incorrect

1. Tighten — replace with smaller main jet

2. Remove obstruction — replace inlet needle — float —

adjust float tab

3. Replace needle jet — replace — adjust jet needle E-

clip

Problem: Carburetor Too Lean (0-1/4 Opening)

Condition

Remedy

1. Choke plunger remains seated

2. Pilot air screw too far out — damaged

3. Piston valve sticks open — damaged — worn

4. Pilot jet — outlet obstructed

5. Float/inlet needle obstructed — damaged — adjusted

incorrectly

1. Adjust — service choke cable — plunger assembly

2. Adjust — replace pilot air screw

3. Service — replace piston valve — throttle cable —

spring

4. Remove obstruction

5. Remove obstruction — replace inlet needle — float —

adjust float tab

4

4-15

Problem: Carburetor Too Lean (1/4-3/4 Opening)

Condition

Remedy

1. Pilot air screw too far out — damaged

2. Needle jet obstructed

3. Pilot jet — outlet — main jet obstructed

4. Float/inlet needle obstructed — damaged — adjusted

incorrectly

5. Jet needle E-clip position incorrect

1. Adjust — replace pilot air screw

2. Remove obstruction

3. Remove obstruction

4. Remove obstruction — replace inlet needle — float —

adjust float tab

5. Adjust E-clip

Problem: Carburetor Too Lean (3/4-WOT Opening)

Condition

Remedy

1. Main jet obstructed — too small

2. Float/inlet needle obstructed — damaged — adjusted

incorrectly

3. Needle jet — jet needle obstructed

1. Remove obstruction — replace with larger main jet

2. Remove obstruction — replace inlet needle — float —

adjust float tab

3. Remove obstruction

Problem: General Fuel System (Engine Cuts Out at High RPM)

Condition

Remedy

1. Fuel delivery inadequate

2. In-line fuel filter obstructed — damaged

3. Gasoline contaminated

4. Gas-tank vent — hose obstructed

1. Repair — replace fuel pump — impulse hose

2. Remove obstruction — replace in-line fuel filter

3. Replace gasoline — de-ice — clean carburetors

4. Remove obstruction — replace vent — hose

Problem: General Fuel System (One Cylinder Runs Lean)

Condition

Remedy

1. Carburetor-to-cylinder air leak

2. Carburetors not aligned vertically

3. Primary compression (crankcase) low

4. Carburetors not synchronized

1. Repair — replace gaskets — flanges — service intake

ports — tighten clamps

2. Align carburetors vertically

3. Troubleshoot engine

4. Synchronize carburetors

 

 

 

 

 

 

 

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