Spark Plug: Adjustment

Clean up the spark plug using nylon brush or equivalent. Clean and remove the carbon or oxide deposits. If deposits are too stubborn, replace the spark plugs. After cleaning the spark plugs, measure the spark plug gap using a gap gauge.

NOTE:

Never use a plug cleaner.
Never use a metal brush because it makes insulator worn.

Spark plug gap: L

0.7 - 0.8 mm (0.028 - 0.031 in)

Fig 1: Identifying Spark Plug Gap

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