Spark Plug: Testing and Inspection

CHECKING THE SPARK PLUGS





1. Disconnect the spark plug cable from the spark plug.

NOTE: Pull on the spark plug cable boot when removing the spark plug cable, not the cable, as it may be damaged.

2. Using a spark plug wrench remove all the spark plugs from the cylinder head.

NOTE: Take care not to allow contaminants to enter through the spark plug hole.





3. Check the spark plugs for the following:
- Broken Insulator.
- Worn electrode.
- Carbon Deposits.
- Damaged or broken gasket.
- Condition of the porcelain insulator at the tip of the spark plug.

ANALYZING THE SPARK PLUGS
4. Engine conditions can be analyzed by the tip deposits near the electrode.
Dark Deposits.
- Too rich a fuel mixture.
- Low air intake.
- White Deposits.
- Too lean a fuel mixture.
- Over advanced ignition timing.
- Loose spark plugs (Under torqued)





5. Check the spark plug gap using a wire gap gauge and adjust if necessary.

Standard Value: 1.0 - 1.1mm (0.039 - 0.043in)





6. Re-insert the spark plugs and tighten to specified torque. Do not overtorque as damage to the threaded portion of the cylinder head may result.

Spark Plug Torque: 20 - 30 Nm (15 - 21ft lb)