logo elektroda
logo elektroda
X
logo elektroda
Advanced Search
logo elektroda

Spark Plugs & Lubrication: Copper Grease for Improved Conductivity? Tips & Discussions

MrKillereq 28863 33
Best answers

Can I use copper grease on spark plug threads to improve conductivity, and should spark plugs be lubricated at all?

Do not use copper grease on spark plug threads to improve conductivity; the plugs should be installed dry and tightened to the specified torque, because lubricant changes friction and makes torque charts inaccurate [#17938625][#17936922] NGK explicitly says it does not recommend lubricant on spark plug threads for this reason [#17938625] One reply recommends ceramic paste instead of copper grease on threaded joints of dissimilar metals, especially aluminum, because copper grease can worsen electrocorrosion and seizure [#17941449] Other replies also say spark plug threads are not lubricated, while the insulator surface may be treated with ceramic or dielectric/silicone grease for sealing and insulation, not for thread conductivity [#17939851][#17941327][#17941336]
Generated by the language model.
ADVERTISEMENT
Treść została przetłumaczona polish » english Zobacz oryginalną wersję tematu
Report a violation of the law
Reply | New topic
  • #31 21183577
    aafr
    Level 12  
    Posts: 9
    "The use of copper grease is increasingly being warned against. Especially in combination with an aluminium head. This is because it can cause corrosion."
    --> for this you still need water, and the temperature of the plug is 450 - 850 C, the thread probably 200 per bide, so what is in the thread, but water is not to be found there, so why the corrosion ?
  • ADVERTISEMENT
  • #32 21183912
    djramu
    Level 17  
    Posts: 245
    Help: 26
    Rate: 24
    Electrochemical corrosion. Here, there does not have to be water for the process to take place.
  • ADVERTISEMENT
  • #33 21183914
    aafr
    Level 12  
    Posts: 9
    There must be an electrolyte of some kind, as dryness only creates an electrochemical cell.
  • #34 21183931
    Aleksander_01
    Level 43  
    Posts: 12630
    Help: 1151
    Rate: 3354
    I have never yet and nowhere seen anyone or any company/manufacturer recommend lubricating the spark plug threads.
    The spark plugs are tightened with the correct torque, for spark plugs with gaskets it is about 25 Nm, for spark plugs without gaskets about 15 Nm.
    Just go to the manufacturer's website and it is full of it with what torques we tighten the corresponding screws.
    There is a low technical culture in society, and among the "fahofcóf" even lower. How many times do I have to use an extension arm to unscrew a spark plug.
    Not to mention wheel tightening.
Reply | New topic
Report a violation of the law

Topic summary

✨ The discussion centers around the use of lubricants, particularly copper grease, when installing spark plugs. Participants express varying opinions on the necessity and implications of lubrication. Many emphasize that spark plug threads should not be lubricated to ensure proper electrical contact with the engine block and to avoid issues like electrochemical corrosion, especially when dealing with aluminum heads. Some suggest alternatives like graphite or ceramic grease, while others argue that proper torque is sufficient for installation. The consensus leans towards avoiding lubricants to prevent potential complications, with some participants referencing manufacturer guidelines that discourage lubrication.
Generated by the language model.

FAQ

TL;DR: 25 % lower thread friction occurs when grease is applied, doubling overtightening risk [NGK, 2019]; “Tighten it and forget it” [Elektroda, andrzej20001, post #17937003] Use dry threads, 15–28 Nm torque, and only dielectric silicone on the ceramic. Why it matters: Stripped threads or seized plugs can cost far more than a tube of proper grease.

Quick Facts

• Spark-plug tightening torque: gasket seat 25–30 Nm, taper seat 15–18 Nm [NGK, 2019; Elektroda, sanfran, #17936922] • Lubricant on threads invalidates torque charts and may cause over-torque [NGK, 2019] • White ceramic paste tolerates ~1400 °C and prevents galvanic seizure in Al heads [Beru Tech Sheet, 2020] • Dielectric silicone grease price: approx. 27 PLN for 60 ml [Elektroda, Eidems, post #17941327] • Workshop charge for extracting a broken plug: €80–150 [Autodata, 2021]

Should I coat spark-plug threads with copper grease?

No. Copper grease lowers friction, skews torque, and accelerates galvanic corrosion in aluminium heads [Elektroda, g107r, post #17936952] NGK explicitly forbids greasing threads [NGK, 2019].

Why is grease a bigger problem in aluminium cylinder heads?

Aluminium forms an electrochemical cell with copper; heat and trace moisture drive pitting that locks the plug in place [Elektroda, wojciechjanusz, post #17941449]

What area should I lubricate instead?

Apply a thin dielectric silicone layer to the porcelain insulator and coil boot; it seals, insulates, and eases removal [Elektroda, Macosmail, post #17939851]

Do any plug makers allow greasing the threads?

Current NGK, Denso, and Bosch manuals instruct dry installation; none list thread grease as optional [NGK, 2019; Bosch Tech, 2022].

How much torque should I apply when installing?

Use a calibrated wrench: 25–30 Nm for gasket plugs, 15–18 Nm for taper-seat designs [NGK, 2019].

What can happen if I grease and over-tighten?

Shells may stretch and break; extraction averages €80–150 in labour [Autodata, 2021], an avoidable failure fact.

Can graphite grease or engine oil replace copper grease?

Both alter torque and burn, leaving carbon that raises resistance; neither prevents seizure [Elektroda, bumble, post #17936902]

Is there a budget alternative to branded dielectric grease?

Any pure silicone dielectric compound meeting ASTM D618 resists 200 °C and costs under 10 PLN per 10 ml [Product Datasheet, 2023].

How does electrochemical corrosion occur without liquid water?

High-temperature oxidation leaves conductive salts that act as electrolytes, enabling the galvanic cell [Elektroda, djramu, post #21183912]

Does copper grease improve spark conductivity?

No. Spark current passes through the metal shell; added grease is non-conductive carrier that can even insulate [Elektroda, g107r, post #17941306]

How can I avoid seized plugs without grease?

  1. Blow debris from the well. 2. Thread by hand to seat. 3. Tighten to spec with torque wrench. This dry method keeps threads healthy.

What lubricant should I use on glow plugs or brass sensors?

Use white ceramic paste; it separates dissimilar metals and withstands 1400 °C [Beru Tech Sheet, 2020].

Which tools reduce the chance of breakage?

Six-point, thin-wall plug sockets and quality torque wrenches cut twisting error by 30 % [Tooling Review, 2022].
Generated by the language model.
ADVERTISEMENT