Spark Plug: Testing and Inspection

Spark Plug Inspection:

1. Inspect the spark plugs for:
- Improper gap
- Carbon deposits
- Cracked center electrode insulator
- Burned or worn electrodes (may be caused by):
- Excessive mileage
- Lean fuel mixture
- Advanced ignition timing
- Loose spark plug
- Plug heat range too high
- Insufficient Cooling
- Fouled plug (may be caused by):
- Rich fuel mixture
- Retarded ignition timing
- Oil in combustion chamber
- Incorrect spark plug gap
- Plug heat range too low
- Excessive idling/low speed running
- Clogged air cleaner element


2. Replace the spark plug if the center electrode is worn or the replacement interval has been reached.

Spark plug type: (Platinum tipped).

Standard Type
PFR5G-11 (NGK)
Cold Type
PFR6B-11 (NGK)
or
PFR7B-11 (NGK)

Spark Plug Gap:

3. Adjust the gap with a suitable gapping tool.

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