anti seize on spark plugs

[kschachn]

Conductivity is not a binary measurement. Some anti-seize products are dielectric. Some conduct well.

True, and I modified my post due to that. Yes some anti-seize products are somewhat conductive, but the metal load is nowhere near what it is in an actual conductive grease. But my original statement about the grease not being conductive is still true.

In this type of application you never want the lubricant to be a conduction path. You always want metal-to-metal contact, which you will have with any grease, assuming there isn't something grossly wrong with the plug or the head.

 

[SC Maintenance]

Copper high temp never seize is conductive, if you want a conductive never seize. I still don't recommend it on the plug threads unless the manual calls for it.

 

[TomYoung]

Who's putting dielectric grease on spark plug threads? That goes on the ceramic part

View attachment 231868

You have a diagram which seems to add credibility, but I am at a complete loss as to what is accomplished by putting dielectric grease on the ceramic insulator. Is there some idea that a conductive film may grow on the ceramic that would not adhere to the grease? I don't get this at all.

 

[kschachn]

You have a diagram which seems to add credibility, but I am at a complete loss as to what is accomplished by putting dielectric grease on the ceramic insulator. Is there some idea that a conductive film may grow on the ceramic that would not adhere to the grease? I don't get this at all.

It helps prevent the rubber boot from sticking to the ceramic, which is a common problem.

 

[TomYoung]

True, and I modified my post due to that. Yes some anti-seize products are somewhat conductive, but the metal load is nowhere near what it is in an actual conductive grease. But my original statement about the grease not being conductive is still true.

In this type of application you never want the lubricant to be a conduction path. You always want metal-to-metal contact, which you will have with any grease, assuming there isn't something grossly wrong with the plug or the head.

In truth, I don't want lubrication on spark plug threads or spark plug ceramics at all.

 

[kschachn]

In truth, I don't want lubrication on spark plug threads or spark plug ceramics at all.

I do. Anti-seize can help remove the plug later, especially on engines where the replacement is 100,000 miles.

And obviously you've never pulled a coil off a plug and had part of the insulator boot stick to the ceramic. That makes it hard to remove the plug. All my vehicle FSM recommend the use of dielectric grease on the inside of the boot.

 

[SC Maintenance]

You have a diagram which seems to add credibility, but I am at a complete loss as to what is accomplished by putting dielectric grease on the ceramic insulator. Is there some idea that a conductive film may grow on the ceramic that would not adhere to the grease? I don't get this at all.

A good friend of mine does this. He claims it stops moisture from getting in. I try to tell him that in the unlikely event any moisture gets in the heat will boil off any moisture in the boot anyway but he is a mechanical engineer, so he is hard to convince (of anything).

 

[kschachn]

A good friend of mine does this. He claims it stops moisture from getting in. I try to tell him that in the unlikely event any moisture gets in the heat will boil off any moisture in the boot anyway but he is a mechanical engineer, so he is hard to convince (of anything).

Yeah, some people are like that.

 

[KevinMalone]

You have a diagram which seems to add credibility, but I am at a complete loss as to what is accomplished by putting dielectric grease on the ceramic insulator. Is there some idea that a conductive film may grow on the ceramic that would not adhere to the grease? I don't get this at all.

Source is from a link shared from post #17: https://mgchemicals.com/blog/dielectric-grease-on-spark-plugs/

They go on to say it's not necessary either. I personally don't bother but one could argue it is good practice

Is Dielectric Grease Necessary for Spark Plugs?​

Strictly speaking, dielectric grease is not necessary for spark plugs to function; however, as noted above, it is a cheap, easy-to-use material that helps ensure the current moves through the spark plug into the ignition system.

 

[TomYoung]

Source is from a link shared from post #17: https://mgchemicals.com/blog/dielectric-grease-on-spark-plugs/

They go on to say it's not necessary either. I personally don't bother but one could argue it is good practice

It does not make the current move through the plug. Someone else said it is all about allowing eventual release of the spark plug boot.

 

[SC Maintenance]

Yeah, some people are like that.

Like when people say specifically that di-electric grease is not an insulator?

 

[Exhaustgases]

The simple answer is. The word Dielectric means an electrical insulator. So if you use said grease on spark plug threads and it also gets on the gasketing area, your sort of blocking the flow of electrical current except in small uncovered areas that exist. If you believe otherwise then you should find an electrical engineer and have them teach you about dielectrics. Not always is a lubricant squeezed out to allow metal to metal contact, that is the whole reason for a lubricant to separate surfaces, and is why you would use a lower torque reading with "lubed" threads.
So the guy that said dielectric grease on spark plug threads is a bad idea, he is very correct.
That grease is meant for the other end of the spark plug, not the threads. It can help keep the terminal end from corroding and helping the boot go on and off easier.

 

[kschachn]

Like when people say specifically that di-electric grease is not an insulator?

I never said that nor did I intend for my statement to mean that. And I explained it to you what the misunderstanding was.

I’m not that stupid.

 

[kschachn]

The simple answer is. The word Dielectric means an electrical insulator. So if you use said grease on spark plug threads and it also gets on the gasketing area, your sort of blocking the flow of electrical current except in small uncovered areas that exist. If you believe otherwise then you should find an electrical engineer and have them teach you about dielectrics. Not always is a lubricant squeezed out to allow metal to metal contact, that is the whole reason for a lubricant to separate surfaces, and is why you would use a lower torque reading with "lubed" threads.
So the guy that said dielectric grease on spark plug threads is a bad idea, he is very correct.
That grease is meant for the other end of the spark plug, not the threads. It can help keep the terminal end from corroding and helping the boot go on and off easier.

There is always something that is separating a surface that is not in contact with another surface. Air is an effective insulator. You are continuing all of the misconceptions that have been discussed in this thread.

Nothing is blocking the flow of current when there is metal-to metal-contact. If grease is in the way then air would be too.

 

[We're Metals]

Haven't used anti seize in the last 10 years. Just like the manufactures.

 

[JeffKeryk]

For all the anti anti-seizure folks: Have you ever had a problem using it? I sure haven't.
I have definitely had problems with stuck plugs...

 

[SC Maintenance]

For all the anti anti-seizure folks: Have you ever had a problem using it? I sure haven't.
I have definitely had problems with stuck plugs...

Never seize - even the regular stuff - is not di-electric. However so as not to re-ignite that discussion - as pointed out, between the torque of thread contacts, the extremely thin film, and the fact your dealing with 20KV minimum, your unlikely to have any issues either way.

My big issue with di-electric is people start using it on other places, where there at 12V, and then it does matter. So I suggest di-electric doesn't really belong on a car. Its intended to seal electrical joints after termination in areas that they may get wet. It does work really well on battery terminals, but honestly given there is no real likelyhood of arc there anyway, so does almost any grease.

The plug OEM's don't want you using it due to the potential to over torque. As long as you compensate for that your fairly unlikely to have an issue.

 

[Exhaustgases]

There is always something that is separating a surface that is not in contact with another surface. Air is an effective insulator. You are continuing all of the misconceptions that have been discussed in this thread.

Nothing is blocking the flow of current when there is metal-to metal-contact. If grease is in the way then air would be too.

With total dielectric coverage there would be no metal to metal contact, I'm sure you can think of many instances where this is true.

"There is always something that is separating a surface that is not in contact with another surface" To quote you.
Yeah so what? What misconception are you talking about? Air you say? And what if it is in a total vacuum?

What would you consider being in contact with another surface? See example below.

First air is not a liquid fluid, and can be displaced easily, in a simple joint that is not designed to use air to float.

Dielectric grease could insulate as good as any other insulator with total coverage. Try using it on 2 precision surfaces, it will be similar to using paint on them.

 

[kschachn]

With total dielectric coverage there would be no metal to metal contact, I'm sure you can think of many instances where this is true.

"There is always something that is separating a surface that is not in contact with another surface" To quote you.
Yeah so what? What misconception are you talking about? Air you say? And what if it is in a total vacuum?

What would you consider being in contact with another surface? See example below.

First air is not a liquid fluid, and can be displaced easily, in a simple joint that is not designed to use air to float.

Dielectric grease could insulate as good as any other insulator with total coverage. Try using it on 2 precision surfaces, it will be similar to using paint on them.

Air is a fluid just like any other. The misconception is that if two metal surfaces are not in contact then somehow the grease that is in the interstitial areas will inhibit conduction.

And for what it is worth, a vacuum has a breakdown voltage just like everything else.

I’ll just put the rest of your post in the same bin as your posts about aviation.

 

[Exhaustgases]

Seem to have a difficult time reading. I said air is not a liquid fluid. Oh yeah its constitutes can become a liquid but that is at a very cold temperature, but air itself is not a liquid. Grease ? no we where all talking about dielectric grease and it will inhibit conduction, just like anyother insulator will. Unless you introduce frequency, and area. Yeah I'm done on this one. Put your own posts there.