Spark Plug: Adjustment

Clean the spark plugs with a wire brush.

Clean and remove the carbon or oxide deposits, but do not wear away porcelain.

If deposits are too stubborn, replace the plugs.

After cleaning the spark plugs, correct the spark plug gap using a gap gauge.

Spark plug gap: L 0.7 - 0.8 mm (0.028 - 0.031 in) 

Fig 1: Cleaning Spark Plugs With Wire Brush

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