Combustion or wear may be caused by the following reasons:
- Early ignition timing
- Loose spark plugs
- Thermal performance (incandescent chichlo) too low.
- Insufficient cooling.
Spark plug contamination can be caused by:
- Late ignition timing.
- Oil in the combustion chamber.
- Incorrect spark plug gap.
- Thermal performance (heat number) too high.
- Excessive idle/low speed revs.
- The air purifier element is clogged.
- The ignition coil or armored ignition wires are damaged.
2. Check the electrode gap.
Adjust the gap with a suitable tool.
Electrode gap
Replace the spark plug if the center electrode is rounded as shown below:
3. Apply a small amount of anti-seize compound to the threaded parts of the spark plugs and screw the spark plugs into the cylinder head with your fingers. Then tighten them to 18 Nm (1.8 kgf.m).