Spark Plug Inspection

K20A4, K20A5, K24A1 (Except KK, KX, KY Models) Engines


1.Inspect the electrodes and ceramic insulator.

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

  • Fouled plug may be caused by:
    • Retarded ignition timing
    • Oil in combustion chamber
    • Incorrect spark plug gap
    • Plug heat range too cold
    • Excessive idling/low speed running
    • Clogged air cleaner element
    • Deteriorated ignition coils

 

2.Check the electrode gap (A). If the gap is over the standard, adjust the gap with suitable gapping tool.

Electrode Gap:
Standard (New): 1.0-1.1 mm (0.039-0.043 in.) 

 

3.Replace the plug at the specified interval, or if the center electrode is rounded (A). Use only the spark plugs listed.

Spark Plugs:
ZFR6K-11 (NGK) 
KJ20DR-M11 (DENSO) 

 

4.Apply a small quantity of anti-seize compound to the plug threads, and screw the plugs into the cylinder head finger-tight. Then torque them to 18 N·m (1.8 kgf·m, 13 lbf·ft).

K24A1 (KK, KX, KY Models) Engine


1.Inspect the electrodes and ceramic insulator.

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

  • Fouled plug may be caused by:
    • Retarded ignition timing
    • Oil in combustion chamber
    • Incorrect spark plug gap
    • Plug heat range too cold
    • Excessive idling/low speed running
    • Clogged air cleaner element
    • Deteriorated ignition coils

 

2.Do not adjust the gap (A) of iridium tip plugs; replace the spark plug if the gap is out of specification.

Electrode Gap:
Standard (New): 1.0-1.1 mm (0.039-0.043 in.) 

 

3.Replace the plug at the specified interval or if the center electrode is rounded (A). Use only the spark plugs listed.

Spark Plugs:
IZFR6K11 (NGK) 
SKJ20DR-M11 (DENSO) 

 

4.Apply a small quantity of anti-seize compound to the plug threads, and screw the plugs into the cylinder head finger-tight. Then torque them to 18 N·m (1.8 kgf·m, 13 lbf·ft).