Where to Apply Spark Plug Insulating Grease?
2 Answers
Spark plug insulating grease should be applied to the threaded part of the spark plug. The purpose of applying insulating grease is to insulate and prevent the rubber part of the high-voltage coil from conducting electricity. The spark plug is mainly composed of a terminal nut, insulator, terminal stud, center electrode, side electrode, and shell. The main types of spark plugs include: standard spark plugs, projected insulator spark plugs, electrode spark plugs, seat spark plugs, pole spark plugs, and surface-gap spark plugs. Spark plugs are installed on the side or top of the engine. In the early days, spark plugs were connected to the distributor via ignition cables. Over the past decade, most car engines have been modified to connect the ignition coil directly to the spark plug. Damaged spark plugs may exhibit the following symptoms: difficulty starting, low power, excessive exhaust emissions, and increased fuel consumption.
I've always enjoyed DIY car repairs, especially when it comes to spark plugs. The spark plug insulating grease is mainly applied to the ceramic insulator part of the spark plug and the junction between the metal threads, specifically where the white ceramic meets the metal. Applying it here helps prevent high-voltage electricity leakage or arcing, while also sealing out moisture and oil to avoid corrosion that could affect ignition efficiency. If you don't apply it or apply it in the wrong place, such as on the electrodes, the spark plug may burn out prematurely, causing engine misfires or increased fuel consumption. The process is simple: after cleaning the spark plug, squeeze out a rice-sized amount of specialized grease and spread it evenly around the junction—don't use too much to avoid getting it elsewhere. It's recommended to do this every time you replace a spark plug to extend its lifespan and improve performance. Remember to use insulating grease, not regular grease, as the latter doesn't prevent electrical issues and can attract dust. This small maintenance step doesn't take much time but is very practical, especially in rainy areas where its effects are most noticeable.
