Polaris 440 IQ - Manual (Page 77)

74
MAINTENANCE
Engine Cooling
Flushing the Cooling System
To ensure that the coolant maintains its ability to protect the engine,
the system should be completely drained every two years and a fresh
50/50 or 60/40 mixture of antifreeze and distilled water should be
added. This service must be done when the engine is cold. Ask your
Polaris dealer to check the coolant when he performs the fall tune-up
on your snowmobile.
WARNING
Steam and hot liquids will cause serious burns to your skin.
Never bleed the cooling system or remove the pressure cap when
the engine is warm or hot.
If the pressure cap needs replacement, contact your dealer for the
correct part. Use of a non-standard pressure cap will not allow the
recovery system to function properly.
Bleeding the Cooling System
CAUTION
If coolant flow becomes restricted or plugged, coolant loss, air
lock or engine damage may result. Most cooling systems are
equipped with a filter that should be periodically inspected or
replaced.
If coolant becomes low in the tank, bleed the system of trapped air
using the following procedure:
1. Allow the system to cool completely, then loosen the bleed screw
and fill the reservoir to the FULL COLD mark. Tighten the screw.
2. Apply the parking brake and run the engine at idle RPM until the
thermostat opens (5 to 8 minutes) and stays open.
NOTE: As the thermostat draws in cold coolant from the heat
exchangers, the cold coolant may close the thermostat.
Make sure it opens and stays open.