Do Spark Plugs Need Anti-seize Lubricant?

kevin brine/Shutterstock

We won't blasted you for adopting nan age-old wont of applying anti-seize lubricant to caller spark plugs, specifically earlier inserting them into nan cylinder head. Besides, anti-seize was conceived specifically to reside corrosion and premature deterioration to metallic parts, either done mixed metallic friction, utmost heat, aliases predominant removal. Most anti-seize products usage high-temperature grease mixed pinch particles of copper, aluminum, aliases nickel, but immoderate are circumstantial to their intended application.

For instance, nan brake caliper bolts should beryllium treated pinch anti-seize erstwhile changing nan brake pads aliases servicing nan rotors, while high-temperature anti-seize grease is awesome for sizzling-hot exhaust bolts that tin sometimes scope 1,000 degrees Fahrenheit. And erstwhile it comes to spark plugs, a small spot of anti-seize connected nan threads wouldn't hurt, right? Especially for those who cognize that removing a seized spark plug is not precisely a locomotion successful nan parkland for nan uninitiated.

However, applying anti-seize is conscionable 1 of those spark plug myths that request to end. Spark-plug master NGK notes that nan lubricating properties of anti-seize tin change nan torque values by up to 20%, which intends expanding nan likelihood of overtightening nan plugs and starring to thread breakage aliases harm to nan cylinder head. In short, applying anti-seize connected nan spark plug threads could beryllium bad news for nan plugs and your car's engine, but nan consequences spell beyond that.

Andrew Berezovsky/Shutterstock

NGK adds that anti-seize increases nan consequence of metallic ammunition stretch, which is simply a fancier connection for immoderate benignant of harm aliases deformity to nan spark plug. Whatever nan case, damaged plugs tin impact their power scope and origin pre-ignition, mediocre performance, and costly soul damage. For your motor and sanity's sake, it's champion to debar anti-seize grease erstwhile installing spark plugs since astir are already treated pinch anti-seize coatings from nan factory.

The shiny chrome aliases metallic decorativeness connected nan threads of caller plugs has little to do pinch their newness and much to do pinch making them easier to region successful nan adjacent servicing. It's what NGK refers to arsenic "trivalent coating" (other spark-plug makers mightiness usage a different name), a typical benignant of plating that prevents metal-to-metal seizing. But for older cars and engines, it's amended to consult nan manual aliases cheque pinch nan shaper earlier proceeding, since immoderate whitethorn require greasing earlier installing. If nan caller plugs person a chrome aliases shiny finish, enactment distant from anti-seize grease. That's nan wide rule.

Finally, periodically replacing nan spark plugs — preferably each 30,000 miles for copper plugs and 60,000 to 100,000 miles for platinum and iridium plugs — and taking utmost attraction that nan threads are moisture-free earlier installing, will forestall them from seizing up successful nan future. Make definite to check nan gaps earlier installing and to torque each plug to spec to forestall issues later on.