Snowmobile Polaris 600 Fusion (2006 year). Manual - part 19

76

OPERATION

Carburetion

Proper carburetor adjustment is critical. A lean mixture (too much air, 

too little fuel) may result in piston burning, bearing failure, or complete 

engine failure.  A rich mixture (too much fuel, too little air) may foul 

plugs and cause generally poor engine performance.  

A lean mixture may be caused by things like fuel line restrictions, for-

eign matter in the carburetor or clogged fuel filters. A rich mixture may 

be caused by snow build-up on the pre-filter in the air intake system. 

Either condition may be caused by improper carburetor adjustment.

WARNING

Improper carburetor adjustments may result in operator safety hazards as 

well as serious engine damage.  Always have your Polaris dealer perform 

any carburetor adjustments.

77

OPERATION

Carburetion

Jetting Guidelines

Changes in altitude and temperature affect air density, which is the 

amount of oxygen available for combustion.  In low elevations and cold 

temperatures, the air has more oxygen.  In higher elevations and higher 

temperatures, the air is less dense.

The carburetors are calibrated for an altitude of 0-2000 ft. (0-600 m) and 

ambient temperatures between -10_ to +10_ F. (-23_ to -12_ C).  Carbu-

retors must be re-calibrated if the snowmobile is operated outside this 

production temperature and/or altitude range.  The main jet installed in 

production is not correct for all altitudes and/or temperatures. See page 

96 for more information.

NOTE: It's the owner's responsibility to ensure that the correct jets are 

installed in the machine for a geographical area.  Be very care-

ful when jetting down in warm weather.  As the weather turns 

colder it will be necessary to re-jet upward to prevent engine 

damage.  When selecting the proper main jet always use the 

lowest elevation and temperature that is likely to be encoun-

tered.

CAUTION

A main jet that's too small will cause a lean operating condition and may 

cause serious engine damage.  Jet the carburetors carefully for elevation and 

temperature according to the jetting charts in your Owner's Manual Supple-

ment.

78

OPERATION

n

Engine Stop Switch

Push down on the engine 

stop switch (

✪) to 

ground out the ignition 

and stop the engine 

quickly. Pull the switch 

up to the ON position to 

allow restarting.

n

Throttle Safety Switch

The throttle safety switch is designed to stop the engine whenever all 

pressure is removed from the throttle lever and the throttle cable or 

valves do not return to the normal closed position.

Test the throttle safety switch 

system daily before operation.

1. Sit on the seat.
2. Start the engine and allow it 

to idle.

3. Hold the throttle lever pin 

stationary by exerting pressure on the pivot pin in the direction 

shown in the illustration.

4. Apply a slight amount of throttle.  A properly functioning switch 

must shut down the engine.

WARNING

Operating the snowmobile with a faulty throttle safety switch can result in 

serious injury or death in the event of an accident.  If the throttle safety switch 

does not shut off the engine during a carburetor/throttle system malfunction, 

immediately push down the engine stop switch.  Do not start the engine 

again until the malfunction has been corrected by your dealer.

✪

79

OPERATION

Throttle Lever

If the engine stops abruptly when the throttle lever is released:

1. Turn the ignition switch to OFF.
2. Visually inspect the throttle cable and carburetor to determine what 

caused the safety switch to activate.

3. Test the throttle lever by compressing and releasing it several times.  

The lever and cable must return to the idle position quickly and 

completely.

4. If the throttle lever operates properly, turn the ignition switch on and 

go through normal starting procedures.

5. If the engine doesn't start, take the snowmobile to an authorized 

Polaris dealer for service.

Excessive freeplay in the throttle cable may cause the safety switch to 

activate, preventing the engine from starting.  If this occurs, return the 

machine to an authorized Polaris dealer for service.  

If an emergency exists and it's necessary to start the engine, the throttle 

safety switch and engine stop switch may be disconnected from the wire 

harness.  When these switches are disconnected, the ignition key switch 

must be used to shut off the engine.  DO NOT continue to operate the 

machine with the throttle safety switch disconnected.  Return the 

machine to an authorized Polaris dealer for service as soon as possible.

WARNING

An improperly functioning throttle lever may cause erratic machine behavior 

and loss of control, which could result in serious injury or death. If the throttle 

lever does not work properly, DO NOT start the engine.