Snowmobile Polaris 600 RMK / 600 PRO RMK / 800 RMK / 800 PRO RMK / 800 RMK Assault. Manual - part 21

86

MAINTENANCE

Spark Plugs

Spark Plug Recommendations

A new engine can cause temporary spark plug fouling due to the preser-
vative added during the assembly process. Avoid prolonged idle speeds, 
which cause plug fouling and carbonization.

Refer to the specifications section for the specific spark plug to be used 
in your snowmobile.

Change the spark plugs at the intervals outlined in the Periodic Mainte-
nance Table beginning on page 77.

• Use recommended spark plugs with the proper gap.
• Use only resistor-type spark plugs.
• Torque spark plugs to 18-22 ft. lbs. (24-30 Nm).
• Always carry spare spark plugs.

NOTICE: Using non-recommended spark plugs can result in serious engine 

damage. A spark plug with a heat range too high will always cause 
engine damage if the engine is operated in conditions more severe 
than intended for that plug. Always use the spark plugs recommended 
for your snowmobile.

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MAINTENANCE

Spark Plugs

Spark Plug Inspection

Spark plug condition is indicative of engine operation. The spark plug 
firing end condition should be read after the engine has been warmed up 
and the vehicle has been driven at higher speeds. Immediately check the 
spark plug for correct color.

CAUTION! A hot exhaust system and engine can cause burns. Wear 
protective gloves when removing a spark plug for inspection.

1. Remove the left side panel.

2. Remove the spark plug cap.

3. Using the special wrench provided in the tool pouch, rotate the 

spark plug counter-clockwise to remove.

4. Reverse the procedure for spark plug installation. Torque to specifi-

cation.

5. Reinstall the spark plug cap.

Spark Plug Condition

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.

TIP: The tip should not be white. A white insulator tip indicates overheating, 

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 or 
use of non-recommended injection oil.

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MAINTENANCE

Oil Lines

Inspect oil line condition every 1000 miles (1600 km) as outlined in the 
maintenance charts beginning on page 77.

Oil Filter

Please see your dealer for replacement of the in-line oil filter every 2000 
miles (3200 km) as outlined in the maintenance charts beginning on 
page 77. 

89

MAINTENANCE

Cooling System

Coolant

The coolant supplied in the system at the factory is a 50/50 mixture of 
ethylene-glycol and distilled water, which will provide adequate freeze 
protection under most conditions. If the vehicle will be stored or oper-
ated at extremely low temperatures, greater protection may be required. 
Please see your POLARIS dealer. 

When adding or changing coolant, POLARIS recommends using Pre-
mium 60/40 anti-freeze coolant, which is already premixed and ready to 
use. Do not dilute with water. Never exceed a 60% antifreeze/40% water 
mixture. See page 116 for POLARIS products.

Never add tap water to the cooling system. Minerals cause deposits and 
may react adversely with the metals in the engine and cooling system.

Coolant Level

The engine coolant level is controlled by the recovery system. The 
recovery system components are:

• Coolant bottle/overflow tank
• Pressure cap
• Connecting hoses

Always maintain the coolant level at or 
slightly above the FULL COLD mark on 
the coolant bottle (when the engine is 
cold).

1. Stop the engine. 

2. Open the right side panel. 

3. View the coolant level in the coolant 

bottle. 

4. Add coolant as needed.

NOTICE: Operating the snowmobile with insufficient coolant will result in over-

heating and serious engine damage. Always maintain the coolant 
level as recommended.

“Full Cold” Mark