How to Change ATV Radiator Fluid

Radiator fluid, or coolant, should be changed at least every two years to prevent corrosion. Coolant is the most important part of your ATV’s cooling system, and the level should be checked every month. Changing the coolant is a simple process that can be completed in under an hour.


1) Locate the coolant tank. On a Polaris ATV, the coolant tank is located next to the oil fill dipstick. It is a white tank and you can see fluid inside. Remove the coolant tank cap. You will see a top cap, an inner cap, and a rubber gasket. Remove all three.

2) Remove the radiator drain bolt and radiator cap. Refer to your owner’s manual for the exact location, but they are generally at the bottom of the radiator. Put a pan under the drain bolt to catch the draining fluid.

3) Remove the air bleeder bolt on the water pump and put a pan under the water pump to catch the draining fluid. Remember to properly dispose of this fluid at a recycling plant. Keep it away from animals and do not dump it in your yard.

4) Screw the bolts back on and fill the radiator with water. Remove the bolts again to let the water drain. Repeat this process until the water drained from the radiator is clean.

5) Premix your ATV coolant with distilled water. A 50/50 mixture is the most common. You can also add anti-freeze and Water Wetter if needed. Refer to your owner’s manual for the correct ratios to use depending on the temperature where your ATV is operated. Each type of ATV will have different recommendations.

6) Put a funnel in the coolant tank and pour your coolant mixture into the funnel. You will see lines on the side of the tank telling you the correct level to pour. Replace both caps and the rubber gasket when you are finished filling the tank.

For ATV maintenance parts see our sponsor