Spark Plug: Testing and Inspection

NOTICE:
- Never use a wire brush for cleaning Spark Plugs.
- Never attempt to adjust the electrode gap on a used Spark Plug.
- Spark Plugs should be replaced every 100,000 km (60,000 miles).

SPARK PLUGS INSPECTION
1. Disconnect high-tension cords from Spark Plugs.




-Disconnect the high-tension cords at the rubber boot.
NOTICE: Do not pull on the high-tension cords. Pulling on or bending the cords may damage the conductor inside.
2. Inspect electrode.




- Using a Megger (insulation resistance meter), measure the insulation resistance.

Standard correct insulation resistance: 10 M Ohms or more
- If the resistance is less than specified, proceed to step 3.
HINT: If a Megger is not available. the following simple method of inspection provides fairly accurate results.
Simple Method:
(a) Quickly race the engine to 4,000 rpm 5 times.
(b) Remove the spark plug. (See step 3)
(c) Visually check the spark plug.




^If the electrode is dry - OK
^If the electrode is wet - Proceed to step 4

(d) Reinstall the spark plug. (See step 7)
3. Remove Spark Plugs.




- Using a 16 mm plug wrench, remove the 4 spark plugs.
4. Visually inspect Spark Plugs.




- Check the spark plug for thread damage and insulator damage.
- If abnormal, replace the spark plug.
Recommended spark plug:
PK20R-11 for ND
BKR6EP-11 for NGK
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 the tip. Never attempt to adjust the gap on the used plug.
6. Clean Spark Plugs.




- If the electrode has traces of wet carbon, allow it to dry and then clean with a spark plug cleaner.

Air pressure: Below 588 kPa (85 psi)
Duration: 20 seconds or less
HINT: 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 4 spark plugs.
Torque: 18 Nm (13 ft lb)
8. Reconnect high-tension cords to Spark Plugs.