Spark Plug: Testing and Inspection

Spark Test:
1. Disconnect the high-tension lead from the spark plug.
2. Connect a new spark plug to the high-tension lead.




3. Hold it with insulated pliers approx. 5-10 mm ( 0.20 - 0.39 in ) from a ground.
4. Crank the engine and verify that a strong blue spark is visible.


Visual Inspection:




Check the following points. If a problem is found, replace the spark plug.
1. Damaged insulation
2. Worn electrodes
3. Carbon deposits
- If cleaning is necessary, use a plug cleaner or a wire brush.
- Clean the upper insulator also.
4. Damaged gasket

Plug gap: 1.0 - 1.1 mm ( 0.040 - 0.043 in )