Cooling System

Content Source: 2021 RZR S4 1000 Owner’s Manual (9931549 R02) > Maintenance Chapter

IMPORTANT

The Owner's Manual for this vehicle contains warnings, instructions and other information you must read and fully understand before safely riding or performing maintenance on this vehicle.Always follow the warnings and instructions in Owner's Manual.

Click the CONTENTS link above for the Table Of Contents, or download a full PDF of the Owner Manual in the Owner Support area of Polaris.com

Cooling System

The engine coolant level is maintained by the recovery system. The recovery system components are the overflow bottle, radiator vent fitting, radiator pressure cap and connecting hose.

As coolant operating temperature increases, the expanding (heated) excess coolant is forced out of the radiator, past the pressure cap, and into the overflow bottle. As engine coolant temperature decreases, the contracting (cooled) coolant is drawn back up from the tank, past the pressure cap, and into the radiator.

TIP

Some coolant level drop on new vehicles is normal as the system is purging itself of trapped air. Observe coolant levels and maintain as recommended by adding coolant to the overflow bottle.

Adding or Changing Coolant

POLARIS recommends the use of POLARIS Antifreeze 50/50 Premix. This antifreeze is already premixed and ready to use. Do not dilute with water. See the Polaris Products section for the part numbers.

To ensure that the coolant maintains its ability to protect the engine, we recommend that the system be completely drained every five (5) years and fresh Antifreeze 50/50 Premix added.

Any time the cooling system has been drained for maintenance or repair, replace the coolant with fresh Antifreeze 50/50 Premix.

Radiators and Cooling Fan

Always check and clean the screens and radiator fins at the intervals outlined in the Periodic Maintenance Chart section. Do not obstruct or deflect air flow through the radiators by installing unauthorized accessories in front of the radiators or behind the cooling fan. Interference with radiator air flow can lead to overheating and consequent engine damage.

NOTICE

Washing the vehicle with a high-pressure hose could damage radiator fins and impair a radiator's effectiveness. Using a high-pressure system is not recommended.

Radiator Coolant Level / Changing Coolant

This procedure is required only if the cooling system has been drained for maintenance and/or repair. If the overflow bottle

has run dry, the level in the radiator should also be inspected.

caution

Escaping steam can cause burns. Never remove the pressure cap while the engine is warm or hot. Always allow the engine to cool before removing the pressure cap.

Remove the hood. See the Hood section for details.
Slowly remove the radiator pressure cap .
View the coolant level through the opening.
Use a funnel and slowly add coolant as needed.
Before reinstalling the pressure cap, bleed the system of trapped air. Remove the engine access panel behind the seats and use a flat-blade screwdriver to turn the bleed screw slightly, allowing the air to escape. Slowly add additional coolant to the radiator until air no longer escapes and only coolant flows from the bleed hole, then tighten the bleed screw.
Reinstall the pressure cap.

TIP

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

Overflow Bottle Coolant Level

Always check and change the coolant at the intervals outlined in the Periodic Maintenance Chart section. Maintain the coolant level between the minimum and maximum marks on the bottle (when the fluid is cool). If the overflow bottle has run dry, the level in the radiator should also be inspected.

Position the vehicle on a level surface.
Remove the hood. See the Hood section for details.
View the coolant level in the overflow bottle .
Remove the cap and use a funnel to add coolant as needed to maintain the level between the two marks.
Reinstall the cap.

TIP

If coolant must be added often, or if the overflow bottle runs completely dry, there may be a leak in the system. Have the cooling system inspected by your POLARIS dealer or authorized person.