Snowmobile Polaris 340 Transport Trail Touring Deluxe (2008 year). Instruction - part 20

80

MAINTENANCE

Spark Plugs

Normal Plug
The normal insulator tip is gray, tan or light brown. There will be few 

combustion deposits. The electrodes are not burned or eroded. This indi-

cates the proper type and heat range for the engine and the service.

NOTE: The tip should not be white. A white insulator tip indicates over-

heating, caused by use of an improper spark plug or incorrect 

carburetor/throttle body adjustments.

Wet Fouled Plug
The wet fouled insulator tip is black. A damp oil film covers the firing 

end. There may be a carbon layer over the entire nose. Generally, the 

electrodes are not worn. General causes of fouling are excessive oil, use 

of non-recommended injection oil, improper use of the choke, or incor-

rect carburetion adjustments.

Spark Plug Removal and Replacement

1. Remove the spark plug cap.
2. Using the special wrench provided in the tool pouch, rotate the 

spark plug counterclockwise to remove it.

3. Reverse the procedure for spark plug installation. 
4. Torque the spark plug to specification. See page 79.
5. Verify that gap is within specification. See your Owner’s Manual 

Supplement.

6. Reinstall the spark plug cap.

81

MAINTENANCE

Intake Filters

The intake foam filter (+) limits snow ingestion into the intake system. 

When operating in loose powder snow, check the top of the foam filter 

periodically to remove any accumulation of snow.

NOTE: These illustrations are general representations. Your model 

may differ.

CAUTION

Operating the snowmobile with the intake filters removed may cause carbu-

retor icing. The result will be poor fuel economy or carburetor malfunction. 

Always reinstall the intake filters before operating the snowmobile.

+

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82

MAINTENANCE

Fuel Filter/Fuel Lines

The fuel filter is located inside the fuel tank. This component requires 

no maintenance.

Inspect the fuel lines regularly for signs of deterioration or damage. 

Always check fuel line condition after periods of storage. Normal dete-

rioration from weather and fuel compounds may occur. Replace worn or 

damaged fuel lines promptly.

Oil Filter

The oil filter on your model is assembled into the oil sending unit 

located in the bottom of the oil tank. This component requires no main-

tenance.

If service is performed to the oil injection system, trapped air must be 

bled from the system. See your dealer for instructions, or have your 

dealer perform this service.

CAUTION

Kinking the fuel lines or using a pliers or similar tools to remove fuel lines 

may cause damage to the lines. If a fuel line has been damaged or kinked, 

replace it promptly.

83

MAINTENANCE

Carburetor

The number stamped in the end of the main jet indicates the jet size. The 

jet installed at the time of manufacture is not necessarily correct for your 

elevation. It's your dealer's responsibility to make sure the correct main 

jet is installed.

Carburetor Adjustments

The frequency at which the carburetors are synchronized or balanced is 

important. Properly adjusted carburetors can greatly improve engine 

performance, fuel economy, engine life, and reliability.

If you notice any of the following conditions, the carburetor may need 

adjustment:
• Hard starting
• Poor idle
• Overheated pistons and cylinder walls
• Plug fouling
• Poor engine response to various throttle valve openings

CAUTION

Operating the snowmobile with incorrect jetting can result in serious engine 

damage. Have your Polaris dealer perform all carburetor adjustments to 

ensure all adjustments are done correctly.