Spark Plug Inspection: Test

How to use this Service Information .

1. Spark Plug - Inspect

   ■ Preconditions 

   • Spark Plug Removed

   ■ Procedure/Specifications 

   NOTE:

   • Do not adjust the spark plug gap, because the electrode may be damaged.
   • Replace the spark plug according to the maintenance schedule.
   • Replace the spark plug with a spark plug from another cylinder if abnormality is suspected, and confirm the change in circumstances.
   • Measure the iridium plug gap with the plug gap gauge (wire type).
   • Do not use a wire brush or scrape the iridium electrode since this will damage the electrode.

   Normal Conditions 

   Position	Inspection items	Specifications
   A	Electrode gap	New: 0.70-0.75 mm (0.0276-0.0295 in)
   B	Worn or deformed electrodes Improper gap Oil-fouling Carbon deposits Cracked center electrode insulator	Inspection items is normal
   C	Damaged gasket
   D	Cracked insulator

   Courtesy of HONDA, U.S.A., INC.

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

   ■ Result 

   • If it is abnormal, replace the spark plug.