
Ever wonder how anti-seize lube works for airplane spark plugs? It’s not uncommon for airplane spark plugs to feature a thin layer of anti-seize lube. Spark plugs, of course, aren’t limited to automobiles. Nearly all airplanes with reciprocating engines use them as well.
Understanding Spark Plugs
Spark plugs provide the initial spark needed for combustion. Reciprocating engines have rods or “pistons” that move and down. During downstrokes, the piston draws fuel and air into the engine’s cylinder via an intake valve. As the valve closes, the piston moves up to compress the mixture.
Spark plugs are designed to ignite the fuel and air mixture. An electric current flows through them, which ignites the highly flammable mixture. This combustion process creates expansion that moves the piston down, thereby turning the crankshaft.
What Is Anti-Seize Lube?
Anti-seize lube is a type of compound that’s designed to create a thin, protective barrier over parts. It essentially protects parts from sticking, galling, corrosion and seizing.
You can use anti-seize lube by applying it directly to the threads. The spark plugs’ threads should be clean and dry. Next, use a brush to apply a thin layer over the threads, ensuring it fully covers all threads starting one or two threads up from the spark plug’s firing end.
How Anti-Seize Lube Works for Spark Plugs
Dealing with stuck spark plugs is frustrating. Spark plugs are typically threaded. Over time, exposure to high temperatures and chemicals can cause them to stick. Fortunately, anti-seize lube offers a solution. It creates a lubricated barrier so that problems such as sticking, galling, corrosion and seizing are less likely to occur.
Most anti-seize lube consists of two key parts: grease and a solid lubricant. Copper is commonly used as a lubricant in anti-seize lube, but others include nickel and aluminum.
Anti-Seize Lube Makes It Easier to Remove Spark Plugs
While anti-seize lube is designed primarily to prevent sticking, galling, corrosion and seizing, it also makes spark plugs easier to remove. Since they are threaded, spark plugs require torque to remove. You’ll have to turn them counterclockwise to loosen and remove them.
Anti-seize lube reduces the required torque. Because it acts as a lubricant, it makes it easier to turn spark plugs.
In Conclusion
Reciprocating aircraft engines typically have two spark plugs per cylinder, but just a single stuck spark plug can create a serious headache for pilots and mechanics. Anti-seize lube offers a solution. It lubricates spark plugs’ threads to protect against sticking, galling, corrosion and seizing.


