Question about using anti-seize on plugs

[CobraBob]

I ran into this information on a website. Any truth to it? I'm asking because I'm changing plugs next weekend and planned to use it.

"Note: Do not use any type of anti-seize compound on spark plug threads. Doing this will decrease the amount of friction between the threads. The result of the lowered friction is that when the spark plug is torqued to the proper specification, the spark plug is turned too far into the cylinder head. This increases the likelihood of pulling or stripping the threads in the cylinder head. Over-tightening of a spark plug can cause stretching of the spark plug shell and could allow blowby to pass through the gasket seal between the shell and insulator."

 

[SVT F15O]

I know on the Lightnings they all say don't use it. Don't see why it would be different on the Cobras. -Mat-

 

[NMRAcer]

just put mine in. didnt use anti seize. never needed it.;-)

 

[CobraBob]

A number of folks here highly recommend it because it is suppose to help prevent stripping the threads on our aluminum heads. Now I'm wondering which is worse?

 

[Cobra'03]

The stock plus have anti-seize - it appears to be copper based.

A-S on spark plugs is not used to avoid stripping the heads- it is used to prevent galling - remember your high school physics? Dissimilar metals react at the molecular level and exchange atoms - over time this can cause them to be very hard to remove. A small dab will not cause any problems. Stress: a small bit - I have actually seen so much aluminum anti-seize glopped on to a plug that it (as a conductor) actually shorted the plug!

Many plugs have a thread coating which is supposed to prevent galling - and if you change plugs a lot, no A-S is likely needed. However, the reason the factory puts on A-S is because at extended change intervals being recommended today, it could be years before the plugs get a twist.

I say it is cheap insurance and i use it - also use it on wheel lugs, and apply a dab evenly distributed across the "face" of the wheel hub - this also prevents galling - ever had a wheel that did not want to brake free?

A little dab 'll do ya.

 

[stangin]

Always use anti-seize on dis-similar metals, especially aluminum and iron (heads and plugs). If you dont its possible that the iron in the plug will actually fuse with the aluminum, as Cobra03 said. Anyone remember the old aluminum intakes with an iron threaded pipe plug to block off the water jacket? Ever tried to remove it? You cant, it fuses to the aluminum intake if you dont use anti-seize and you would break the aluminum intake trying to get it out. I use anti-seize on almost everything. When you torque the plugs, finger tight then just a smidge more with the ratchet, they will not come lose. If your worried about it you can retorque after 5000 - 10,000 miles if you want.

 

[CobraBob]

Originally posted by Cobra'03
it is used to prevent galling - remember your high school physics? Dissimilar metals react at the molecular level and exchange atoms.

:lol: I'm supposed to remember a class I barely passed 40 years ago?

Thanks for the additional info. I'm convinced I will use it now. This Forum is the best and any Cobra owners not using it are missing a lot!
:beer: