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2018-2021 ACE 150 Spark Plug Inspection and Replacement

Required Tools and Supplies

  • Shop Rags
  • Torque Wrench
  • 5/8-Inch Spark Plug Socket
  • Safety Glasses
  • Ratchet
  • Nitrile Gloves

To learn more about tools, read the Tools and Fasteners Guide. Always wear safety glasses and  nitrile gloves when servicing your Polaris ACE.

To inspect and replace the spark plug on your ACE 150, follow these steps:

1. Park the vehicle on a flat, level surface and allow the vehicle to cool completely.

2. Ensure the parking brake is set.

3. Clean the area around the spark plug.

4. Remove the spark plug cap.

5. Using a 5/8-inch spark plug socket, remove the spark plug by rotating it counterclockwise.

6. Inspect the electrodes for wear and carbon buildup. The spark plug should have a sharp outer edge with no rounding or erosion of the electrodes.

7. Inspect and adjust the spark plug gap if necessary. The gap should be 0.024 to 0.028 inches (0.6 to 0.7 mm).

8. If necessary, replace with the recommended spark plug. The spark plug for an ACE 150 is NGK® CR7HSA (part number 3050051). Severe engine damage may occur if the incorrect spark plug is used.

9. Reinstall the spark plug. Torque a new spark plug to 9 to 11 ft-lbs (12-15 Nm). Torque a used spark plug to 17 to 20 ft-lbs (23-27 Nm).

10. Reinstall the spark plug cap and ensure it is fully seated.

11. Finally, start the engine and check for any warning lights.

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.

Unless noted, trademarks are the property of Polaris Industries Inc.
© 2022 Polaris Inc.