Snowmobile Polaris Trail RMK (2010 year). Manual - part 14

57

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.
RMK carburetors are preset to operate at altitudes of 6000-8000 feet 

(1800-2400 m) above sea level (see page 78 for more information). Car-

buretors 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.

NOTICE: 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. See your 

Owner’s Manual Supplement.

Tip: It’s the owner’s responsibility to ensure that the correct jets are installed in 

the machine for a geographical area. Be very careful 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.

58

OPERATION

n

Engine Stop Switch

Push down on the engine 

stop switch to stop the 

engine in an emergency. 

This will ground out the 

ignition and bring the 

engine to a quick stop. 

To restart the engine, the 

switch must be pulled up 

to the ON position.

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.

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.

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 pres-

sure 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.

Stop Switch

59

OPERATION

n

Throttle Lever

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.

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(s) 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 free play 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.

60

OPERATION

Emergency Stopping

The following chart lists methods for stopping the snowmobile in the 

event of an emergency. Refer to page 58 for more information about the 

engine stop switch and throttle safety switch.

WARNING! Excessive or repetitive use of brakes for high speed stops will 

cause an overheated brake system. This overheated condition could cause 

sudden loss of brakes and/or fire, resulting in serious injury or death. When 

traveling on long downhill stretches, pump the brakes. Riding the brakes may 

cause the brake system to overheat and result in brake failure.

SYSTEM

WHAT IT DOES

THROTTLE

CONDITION

Ignition Switch

Interrupts ignition circuit

All

Brake

Slows jackshaft

All

Choke

Floods engine

Half throttle or less

Engine Stop Switch

Interrupts ignition circuit

All

Throttle Safety Switch

Interrupts ignition circuit

All