Spark Plug: Testing and Inspection
SPARK PLUG INSULATION INSPECTIONNOTICE:
- Never use a wire brush for cleaning.
- Never attempt to adjust the electrode gap on a used spark plug.
- Spark plugs should be replaced every 100,000 km (60,000 miles).
1. REMOVE IGNITION COILS
2. INSPECT ELECTRODE.
- Using a megger (insulation resistance meter), measure the insulation resistance.
Standard correct insulation resistance: 10 M Ohm or more.
- If the resistance is less than specified, proceed to step 4.
HINT: If a megger is not available, the following simple method of inspection provides fairly accurate results.
SIMPLE METHOD:
- Quickly race the engine to 4,000 rpm 5 times.
- Remove the spark plug. (See step 3)
- Visually check the spark plug.
- If the electrode is dry... OK.
- If the electrode is wet... Proceed to step 4.
- Reinstall the spark plug. (See step 7).
3. REMOVE SPARK PLUGS.
- Using a 16 mm plug wrench, remove the 6 spark plugs from the RH and LH cylinder heads.
4. VISUALLY INSPECT SPARK PLUGS.
- Check the spark plug for thread damage and insulator damage.
- If abnormal, replace the spark plug.
Recommended spark plug:
- ND: PK20R11
- NGK: BKR6EP11
5. INSPECT ELECTRODE GAP.
Maximum electrode gap for used spark plug: 1.3 mm (0.051 in.)
- If the gap is greater than maximum, replace the spark plug.
Correct electrode gap for new spark plug: 1.1 mm (0.043 in.)
NOTICE: If adjusting the gap of a new spark plug, bend only the base of the ground electrode. Do not touch tip. Never attempt to adjust the gap on the used pit.
6. CLEAN SPARK PLUGS.
- If the electrode has traces of wet carbon, allow dry and then clean with a spark plug cleaner.
Air pressure: Below 588 kPa (6 kgf/cm2, 85 psi).
Duration: 20 seconds or less.
NOTE: If there are traces of oil, remove it with gasoline before using the spark plug cleaner.
7. REINSTALL SPARK PLUGS.
- Using a 16 mm plug wrench, install the 6 spark plugs.
Torque: 18 Nm (13 ft.lb)
8. REINSTALL IGNITION COILS.
- Refer to Ignition Coil Service & Repair.