Polaris Hawkeye 325 2X4 2016 Owner's Manual For Maintenance And Safety page 120

MAINTENANCE
Breather Valve/Hose (450/570)
The breather valve is on the hose that runs between the engine and air
box. See illustration on page 117.
1. Remove the left side panel. See page 113.
2. Remove the hose clamps from the valve and pull the valve out of
the hoses.
3. Inspect the valve for debris. Blow gently through the valve to check
for clogging. Replace a damaged or clogged valve.
4. Check the hoses for cracks, deterioration, abrasion, or leaks.
Replace as needed.
5. Reinstall the valve and hose clamps.
NOTICE: Operation of your vehicle without a breather valve can cause engine
damage. Always reinstall the breather valve after removing it for
service.
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