Snowmobile Polaris 800 RMK / 800 Pro-RMK / 800 RMK (2010 year). Manual - part 20

81

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 104 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

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MAINTENANCE

Cooling System

Engine Overheating

The over-temperature indicator on the 
instrument cluster will illuminate when the 
engine is overheating. The indicator will 
flash when engine temperature reaches 
critical levels. 

Illuminated Indicator

Take action to cool the engine:

• Drive in loose snow.
• View the coolant level. Do not open the 

pressure cap while the engine is hot. 
Add coolant if the level is low.

• Stop the engine and allow it to cool down.

If you must continue to operate while the indicator light is illuminated, 
drive slowly and stop the engine frequently to allow it to cool down.

Flashing Indicator

If the indicator flashes, continued operation could result in serious 
engine damage. The system will automatically reduce engine power and 
create a misfire condition. Stop the engine immediately. Allow the 
engine to cool down.

If engine overheating seems to be caused by something other than poor 
cooling conditions, see your dealer for service.

Flushing the Cooling System

To ensure that the coolant maintains its ability to protect the engine, 
drain the system completely every two years and add a fresh mixture of 
antifreeze and distilled water. This service must be performed when the 
engine is cold. Ask your POLARIS dealer to check the coolant when he 
performs the fall tune-up on your snowmobile.

83

MAINTENANCE

Cooling System

Bleeding the Cooling System 

CAUTION! Steam and hot liquids will cause burns to your skin. Never bleed the 
cooling system or remove the pressure cap when the engine is warm or hot.

Use of a non-standard pressure cap will not allow the recovery system to 
function properly. If the pressure cap needs replacement, contact your 
dealer for the correct part.

NOTICE: If coolant flow becomes restricted or plugged, coolant loss, air lock or 

engine damage may result.

1. Position the vehicle so that the top of the tunnel is level. Elevate the 

front of the vehicle slightly if necessary.

2. Make sure the engine is cold before continuing.

3. Remove the right side panel. 

4. Fill the coolant bottle with properly mixed coolant to the maximum 

mark. Do not install the pressure cap at this time.

5. Remove the bleed screw from the water outlet manifold and/or the 

thermostat housing. Allow the coolant to bleed through the system 
until it runs out the bleed holes. Reinstall the bleed screw into the 
manifold.

6. Add coolant to the coolant bottle to the maximum mark.

7. Reinstall the side panel. Always ensure that the hood and side pan-

els are securely in place before starting the engine.

8. Start the engine and run at a fast idle for two to three minutes. 

Loosen the bleed screw occasionally to purge any trapped air.

9. Stop the engine and check the coolant bottle level. Add coolant as 

needed. Reinstall the side panel.

10. Carefully and briefly touch the top of the tunnel cooler under the 

seat. If the system is bled properly, the cooler will be warm to the 
touch. If not, repeat step 8. Lift the front of the snowmobile slightly 
to assist in the bleeding.

11. Remove the side panel. Reinstall the pressure cap. Reinstall the side 

panel.

12. Carefully lower the front end of the snowmobile.

84

MAINTENANCE

Exhaust System

Check the exhaust system for wear or damage at approximately 2000 
miles (3200 km). Always allow the engine and exhaust system to cool 
completely before inspecting. 

CAUTION! Hot exhaust system parts can cause burns. Allow adequate time for 
the exhaust system to cool. Never perform this procedure with the engine 
running.

1. Open the side panels and remove the hood. See page 73.

2. Inspect the muffler and pipes for cracks or damage.

3. Check for weak or missing retaining springs or damper/support 

grommets.

4. Check for loose clamps on the pipe covers.