Procedure
1. Disconnect the cable from the negative terminal of the battery. Using the tip, disconnect the high-voltage wires from the spark plugs.
Caution: When disconnecting spark plug wires from spark plugs, pull on the wire tip, not the wire, as it may be damaged.
2. Remove the spark plug using a spark plug wrench. To avoid damaging the spark plug, install the spark plug wrench strictly along the spark plug axis.
Warning: Use compressed air to clean the spark plugs to prevent dirt from getting into the engine cylinders after removing the spark plugs.
3. Check the spark plugs for the following defects:
- 1) damage to the insulator;
- 2) worn electrodes;
- 3) carbon deposits;
- 4) damage to the gasket;
- 5) the condition of the insulator at the tip of the spark plug.
4. Use a wire gauge to check the spark plug gap. The gap is adjusted by bending the side electrode.
The spark plug gap is of great importance because if the gap is too large or too small, the spark size changes, which leads to a decrease in engine efficiency. The gap must always comply with technical requirements.
The central electrode must not be bent under any circumstances, as this may lead to breakage of the insulator and failure of the spark plug. To bend the side electrode of the spark plug, you need to use a special tool.
- Spark plug gap: 1.0–1.1 mm
5. Screw the spark plug into the cylinder head. Tightening torque: 20–30 Nm.