Spark Plug: Testing and Inspection

SPARK PLUG / INSPECTION







1. Inspect the electrodes and ceramic insulator for:

Burned or worn electrodes may be caused by:
- Advanced ignition timing
- Loose spark plug
- Plug heat range too low
- Insufficient cooling

Fouled plugs may be caused by:
- Retarded ignition timing
- Oil in combustion chamber
- Incorrect spark plug gap
- Plug heat range too high
- Excessive idling/low speed running
- Clogged air cleaner element
- Deteriorated ignition coil or ignition wires







2. Adjust the gap with a suitable gapping tool, and replace the plug if the center electrode is rounded as shown below.

Electrode Gap:
Standard 1.1 ± 0.1 mm (0.043 ± 0.004 in)

NOTE: Use only the spark plugs listed below.

Spark plug
NGK - ZFR5F-11
Denso - KJ16CR-L11

3. Apply a small quantity of anti-seize compound to the plug threads before installing the plugs.
4. Screw the plugs into the cylinder head finger-tight, then torque them to 18 Nm (13 lb.ft).