Spark Plug: Adjustment

Clean spark plugs with a nylon brush, etc. 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 plug cleaner.
Do not use metal brush or it will wear insulator.

Spark plug gap L:

1.0 - 1.1 mm (0.039 - 0.043 in)

Fig 1: Identifying Spark Plug Gap

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