Required Tools and Supplies:
- 5/8-inch Socket
- 10mm Socket
- 10mm Wrench
- Torque Wrench
- Shop Rags
- Nitrile Gloves
- Eye Protection
Always wear safety glasses and nitrile gloves when servicing your Polaris ATV. To change the spark plugs on your model year 2021 and newer Sportsman 450, follow these steps:
1. Park the vehicle on a flat, level surface, ensure it is in PARK, set the parking brake and remove the key.
2. Unlatch the front storage compartment straps and open the compartment.
3. Remove the black negative battery cable fastener first with a 10mm socket and wrench to prevent arcing. Set the cable aside. Reinstalling the fasteners into the post will help prevent misplacement.
4. Lift up on the rear of the seat and pull back to remove.
5. Remove the two push-pin rivets from the left side panel.
6. Grasp the rear of the side panel and pull back to disengage it from the retainers and remove it from the vehicle. To avoid the risk of burns, allow the engine and exhaust to cool completely before continuing.
7. Reach in through the right wheel well and around the exhaust system to reach the spark plug.
8. Clean the area around the spark plug to prevent debris from falling into the engine.
9. Carefully lift up to remove the spark plug boot from the plug.
10. Carefully remove the spark plug with a 5/8-inch spark plug socket for inspection.
11. Inspect the electrodes for wear and carbon buildup. The spark plug should have a sharp outer edge with no rounding or erosion.
12. Inspect and adjust the spark plug gap if needed. The gap should be 0.033 inches (0.084 mm).
13. If necessary, replace with the recommended spark plug. The spark plug is part number 3023515.
14. Install the spark plug into the engine. Torque to 15 ft-lbs (20 Nm).
15. Reinstall the spark plug boot and ensure it is fully seated.
16. Align the retention tabs on the side panel and pivot the panel into place.
17. Reinstall the push-pin rivets to secure the panel.
18. Reinstall the seat by aligning the front retaining tabs and pushing down in the rear.
19. Move to the front of the vehicle and reinstall the negative battery cable to the battery. Torque the cable to 62 in-lbs (7 Nm).
20. Close the front storage compartment and secure the two straps.
21. Start the engine to ensure proper operation. When the battery is disconnected, the vehicle’s clock may need to be reset.
For more information, see your authorized Polaris Dealer. Find a dealer near you with the Dealer Locator.
Maintenance tips, procedures and specifications can be found in your Owner's Manual.
To find diagrams and replacement part numbers, use the online parts catalog.
NGK® is a registered trademark of NGK Spark Plug Co., Ltd.