Spark Plug: Testing and Inspection

Fig. 4 Spark plug inspection:

Visually inspect the spark plugs for the following conditions: If any defect is found replace the spark plug:
1. Check for damaged insulation.
2. Check for worn electrodes.
3. Check for carbon deposits. Clean with a wire brush if necessary.
4. Check for damaged gasket.

Plug gap: 2.0mm (0.08in)

Note: Do not use a plug cleaner. Cleaning sand may remain lodged in the plug and eventually cause engine damage.

NGK Nippon Denso Identification mark
Trailing SD 11A S-31A T, Blue Line
Leading SD 10A S-29A L

Caution: Install the correct type spark plug after confirming the identification mark.