Lube spark plug threads, and if so, modify torque spec?

[LavaRand]

Presence or absence of lubrication can change recommended torque spec by a factor of 2 or more.

My pentastar spark plugs are specd at 18 lb-ft. But it doesn't say anything about lubing the threads. So I have to assume it's specd dry. For an aluminum head, I would normally use anti-sieze, but if I do that, does it mean the 18 foot pound spec is invalid then? I don't want to over torque or strip the head either.

 

[chemman]

This has been discussed many times on here. I believe the consensus is if you choose to use anti-sieze, then torque the spark plugs to 80% of the stated torque value. So in your case, you would torque to 14.4 ft-lbs.

 

[billt460]

This has been discussed many times on here. I believe the consensus is if you choose to use anti-sieze, then torque the spark plugs to 80% of the stated torque value. So in your case, you would torque to 14.4 ft-lbs.

This is the general rule that I've applied through the years. And it's worked very well. I have never had a lubricated bolt or a nut come loose. That is a fallacy that just wont seem to die in regards to applying lube or anti seize to threads.... Including lug nuts.

 

[Gillsy]

I read an article from a plug manufacturer (don't recall name) that stated "do not lubricate the threads when installing the plugs. The plugs are threads are treated with a non-stick coating during manufacture". Are all plugs coated? I really don't know. I think the general rule of thumb is that, unless otherwise stated, torque spec. is stated for clean dry threads. Reduce torque by 10% if lubricated.

 

[ka9mnx]

Some spark plugs come pre-lubed. My 50 year calibrated right arm is my torque wrench.

 

[willbur]

This has been discussed many times on here. I believe the consensus is if you choose to use anti-sieze, then torque the spark plugs to 80% of the stated torque value. So in your case, you would torque to 14.4 ft-lbs.

Yet many fastener torque specs are based on threads lightly lubed by oil. But others assume dry. Very confusing. I assume the fastener is dry and reduce by 20% to be safe. In my opinion, lubing threads is ok- AZ under the fastener head is where one needs to be careful. It's even more confusing when Permatex says to use normal torque spec with their AZ.

 

[LavaRand]

I was actually more worried about heat transfer. NGK says that using lube on the threads is like going up by two heat ranges. But it just seems wrong to me to put them into an aluminum head dry.

 

[Blueshound]

I fixed cars for a living for 10 years (about 20 years ago). Replaced thousands of spark plugs, almost all NGK or Bosch plugs in aluminum heads (Japanese and Euro). We always used silver never-seize on the threads and never had a stripped thread, plug failure or stuck plug afterwards. This is probably terrible, but I don't think I ever used anything but the "right arm" torque wrench.
Based on this experience, I think there is a LOT of margin of error installing spark plugs.
Getting the old ones out (mostly oem unlubricated) is a different story of pain and heartache.
Long story short, I will never install a spark plug without never seize.

 

[willbur]

I was actually more worried about heat transfer. NGK says that using lube on the threads is like going up by two heat ranges. But it just seems wrong to me to put them into an aluminum head dry.

Now that is interesting. Two heat ranges are a lot. Care to share your info or source?

 

[Schandyman]

dry install for me.. plugs may have left over machining oil when they're threaded.

 

[kschachn]

Every spark plug I've installed lately has a torque angle listed on the box. If you use that then the torque value is not needed.

And yes there have been numerous and lengthy threads on this subject already. Here are a few but there are more:

Changing spark plugs - do I need Anti Seize?

Will be changing my spark plugs this weekend - do I need to spray any Anti Seize on them?

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Some car makers say NO antiseize on spark plugs?

I know that Volkswagen specifically stated that you should not use antiseize when installing spark plugs....other than the slight possiblity you might have some drip onto the electrode if you used too much would there be any other reason? I have always used a small amount of 10w/30 oil on the...

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Anti seize on spark plugs

I'm doing my first ever spark plug job tomorrow on my 2003 Jetta. I am confused as to whether or not I should use anti-seize, as I've read varying opinions. The plugs are autolite platinum. I am currently thinking I don't need to use them as the platinum ones aren't as likely to seize as...

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Using anti-seize on spark plugs or not

When installing spark plugs on a Ford F 150 equipped with the 300 inline six engine should I use a little anti-seize on the threads or not? The plugs for this engine don't have many threads on them, maybe six or seven full threads at most, unlike some other plugs. (NGK recommends not using...

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What type anti-seize for spark plugs?

What type anti-seize should I use for installing spark plugs in aluminum heads? I have the copper type and the silver type. Does one work better than the other? Will one run into the spark gap and cause a misfire, or will it cause a hot spot and preignition? thanks

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Spark Plugs! - This belongs in the oil forums!

So we have beat the old mobil 1 vs castrol vs pennzoil to death, I have a new topic for the BITOG crew. Do you change your oil after you do your plugs? I always do I don't want the crud going into the block and recrulating till the pesky filter gets to it. Chime in, I have yet to find any...

bobistheoilguy.com

Question about anti-seize on spark plugs?

I had ngk dbl platinum spark plugs installed and then i got home and read on ngk is website not to use anti-sieze so Im not happy that the mechanic used anti-sieze on the plug threads even though it was just a lil dab on each and but he hand tighten them which is a good thing at least. Ngk...

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Honda Spark Plug Torque Dilemma

I recently did a set of spark plugs on a Gen 3 CRV. The service manual states to use a light coat of anti-seize on the spark plug threads, and to torque to 13 ft-lbs. I used the Denso SKJ20DR-M11 plugs, which are the OES plugs and were also the factory-installed plugs. I was discussing this...

bobistheoilguy.com

 

[tasch72]

I read an article from a plug manufacturer (don't recall name) that stated "do not lubricate the threads when installing the plugs. The plugs are threads are treated with a non-stick coating during manufacture". Are all plugs coated? I really don't know. I think the general rule of thumb is that, unless otherwise stated, torque spec. is stated for clean dry threads. Reduce torque by 10% if lubricated.

I believe that manufacturer is Autolite

If the plugs are nickel plated (gray color), Autolite recommends only using anti-sieze where OE recommended. They also state that anti-sieze alters the torque by as much as 20%.

 

[Silver]

I've got to where I'll put a light coat of antiseize on a rag and turn the plug through it while holding the rag tight around the plug. This leaves a very thin layer that you can't see, but can barely and I mean BARELY feel on the plug threads. This satisfies my inner conflict about this topic for which I frankly have no desire to put forth the effort needed to reach a scientifically correct answer!

 

[JeffKeryk]

Just don't slab it on... I use a very slight brush on one side.

 

[paulo57509]

I use Champion 2612 (sparingly) on spark plugs going into aluminum heads. I reduce torque accordingly.

 

[HankHill]

I use copper anti-seize and very lightly put a coating on. Done about 200 plugs, never had a problem with repeat changes, and I've never had one come "loose" either.

If it was a Ferrari I'd use a torque wrench.. But otherwise I've used the arm method for 18 years, and again I've never had one come in loose or one get stuck in any way.

I see people use torque specs on stuff that has no reason, and I ask them to articulate why.. Normally I like them, and most of the time its due to strict spec following, or monetary value they paid for their car. Each to their own!!

 

[LavaRand]

I used regular cheap permatex anti seize. The plugs said to torque 1/4 turn after bottoming. I did that on one bank. For the second bank, I tried torquing to spec of 18 lbft for giggles. Torquing resulted in turning slightly LESS than 1/4 turn.

 

[willbur]

I used regular cheap permatex anti seize. The plugs said to torque 1/4 turn after bottoming. I did that on one bank. For the second bank, I tried torquing to spec of 18 lbft for giggles. Torquing resulted in turning slightly LESS than 1/4 turn.

Interesting. Maybe Permatex is correct after all in recommending normal torque when using that AZ?

 

[tcp71]

I use just the slightest bit of 1600 degree anti seize. Never a problem and make removal a piece of cake.

 

[Marcozi]

Steel sparkplugs and an aluminum head are a recipie for removal issues. I put a tiny dab of copper anti-seize on the threads, and then use a clean paper towel, wrapped tightly around the threads, to spread the compound evenly, and remove any excess.