Spark Plug Inspection and Cleaning

1. Disconnect the high-tension spark plug cables from the spark plugs.

When disconnecting a high-tension spark plug cable, pull on the insulating boot, not on the cable itself. Otherwise the cable may be damaged.

2. Using a spark plug socket, remove the spark plugs from the cylinder head.

3. Inspect the spark plugs for the following defects:

1) Damaged insulator 2) Worn electrodes 3) Carbon deposits 4) Damaged or cracked gasket washer 5) Condition of the insulator enamel at the plug tip

4. Check the spark plug electrode gap using a wire gauge, and adjust if necessary.

Specification: 1.0 – 1.1 mm

5. Install the spark plugs and tighten them to the specified torque.

If the spark plugs are tightened to a torque exceeding the specified value, the threads in the cylinder head may be damaged.

Torque: 20 – 30 N·m

ENGINE DIAGNOSIS BY SPARK PLUG CONDITION

The engine condition can be evaluated by the deposits on the center electrode insulator.