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Spark Plug: Service and Repair



SPARK PLUG REPLACEMENT

REMOVAL PROCEDURE
1. Remove the spark plug wires.




2. Loosen each spark plug 1 or 2 turns.
3. Brush or air blast away any dirt from around the spark plugs.
4. Remove the spark plugs 1 at a time. Place each plug in a tray marked with the corresponding cylinder numbers.

INSTALLATION PROCEDURE




1. Properly position each spark plug washer.
2. Inspect each spark plug gap. Adjust each plug as needed.

Spark plug gap: 1.02 mm (0.040 in)

3. Hand start the spark plugs in the corresponding cylinders.

NOTE: Refer to Fastener Notice in Service Precautions.

4. Tighten the spark plugs.
- For used heads tighten the spark plugs to 15 N.m (11 lb ft).
- For new aluminum heads tighten the spark plugs to 20 N.m (15 lb ft).
- For new iron heads, tighten the spark plugs to 30 N.m (22 lb ft).

5. Install the spark plug wires.