Spark Plug: Testing and Inspection

NOTE: Before cleaning, inspect the spark plug insulators and electrodes for indications of oil fouling, rich mixture, or improper heat range. Refer to the Spark Plug Inspection Chart.





- Clean the spark plugs with a wire brush or sandblast cleaner, if available.
- Check the electrode gaps. If necessary, adjust the gap clearance to 1.0-1.1mm (0.039-0.043 in).