With aluminum heads, I find the plugs come out best when warm.
The threads are looser when they are expanded a bit.
The threads are looser when they are expanded a bit.
Question about anti-seize on spark plugs?
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Originally Posted By: Kiwi_ME
Originally Posted By: mechtech2
Too much AS can also alter the heat transfer of the plug to the head, and change the heat range - it can run too hot.
I can't imagine any scientific analysis that would support that suggestion. The AS is not going to keep the threads from touching.
Instead of thread to thread contact, there is thread to substance to thread.
Pretty scientific, isn't it?
When I worked at Mercedes, they cautioned against anti seize for this reason.
Originally Posted By: mechtech2
Too much AS can also alter the heat transfer of the plug to the head, and change the heat range - it can run too hot.
I can't imagine any scientific analysis that would support that suggestion. The AS is not going to keep the threads from touching.
Instead of thread to thread contact, there is thread to substance to thread.
Pretty scientific, isn't it?
When I worked at Mercedes, they cautioned against anti seize for this reason.
Quote:
Instead of thread to thread contact, there is thread to substance to thread
True but copper and nickel both have heat conductive properties, like heat sink to CPU compound.
I never has any issues in 38 yrs using it almost daily. I have had a lot more issues with stuck plugs over the years though.
Just a thought.
Instead of thread to thread contact, there is thread to substance to thread
True but copper and nickel both have heat conductive properties, like heat sink to CPU compound.
I never has any issues in 38 yrs using it almost daily. I have had a lot more issues with stuck plugs over the years though.
Just a thought.
I've also seen the warnings against anti-seize grease from several plug manufacturers (and if my memory's correct, Porsche as well), and I'm sure it's for a good reason (compromising the plug's electrical ground would be an obvious complication). That said, I'll never forget an experience in the 1980s when I wrestled with a seized spark plug for an hour on my mom's 1970 Mercury wagon, and I swore then-and-there that I'd NEVER install another plug without grease. Never had a problem since then using lube. If it makes ya feel any better, I have a Haynes repair manual at home that specifically recommends spark plug lube, so it's not a "freaky deaky" habit (to steal a line from Austin Power's Dr. Evil). I also use only anti-seize products that specifically mention spark plug applications, although that may or may not be truly necessary. Short version: I wouldn't even consider installing a plug without an anti-seize compound.
This is a bit interesting:
http://forums.audiworld.com/showthread.php?t=1491041
Would of been nice if he had heat cycled it a few times to see if it changed conductivity though.
http://forums.audiworld.com/showthread.php?t=1491041
Would of been nice if he had heat cycled it a few times to see if it changed conductivity though.
I have been using anti-seize on plugs for the last 25 years with zero problems. They seem much easier to change when it comes time. As long as you don't slop it on I wouldn't expect problems. A little dab will do ya.
Originally Posted By: doitmyself
My Caravan specifies Champion or NGK plugs. Both recommend not to use anti seize. Yet, my factory service manual DOES recommend to use anti seize.
This NGK bulletin http://www.ngkplugpro.ca/content/contentfiles/pdf/NGKSP-0907-1R-Anti-SeizeonSparkPlugs.pdf recommends no anti seize on "shiny, plated spark plugs", but DOES recommend anti seize on plain steel, non plated plugs. So, if the "bad" effects of anti seize can be avoided in one scenario, why not the other?
This difference of opinion will never be resolved, but I am gently being tugged to the no anti seize camp now that all mfg. seem to state this. Next plug change will be interesting.
FWIW, Honda also says to use a light amount of anti-seize and torque to 13 ft-lbs. Usually, with dry threads, one would torque to 18 ft-lbs for the same size plug - so their recommended torque spec is about 25% less.
Regardless, NGK states to use no anti-seize, so there's a dilemma there. Denso makes no recommendation as far as I know. I installed a set of plugs last night with anti-seize (Denso SKJ20DR-M11) and I did not care for the feel of the threads at all...in fact I thought it was a bit nervewracking. I much prefer the progressive, solid feel of clean and dry threads when torquing spark plugs.
My Caravan specifies Champion or NGK plugs. Both recommend not to use anti seize. Yet, my factory service manual DOES recommend to use anti seize.
This NGK bulletin http://www.ngkplugpro.ca/content/contentfiles/pdf/NGKSP-0907-1R-Anti-SeizeonSparkPlugs.pdf recommends no anti seize on "shiny, plated spark plugs", but DOES recommend anti seize on plain steel, non plated plugs. So, if the "bad" effects of anti seize can be avoided in one scenario, why not the other?
This difference of opinion will never be resolved, but I am gently being tugged to the no anti seize camp now that all mfg. seem to state this. Next plug change will be interesting.
FWIW, Honda also says to use a light amount of anti-seize and torque to 13 ft-lbs. Usually, with dry threads, one would torque to 18 ft-lbs for the same size plug - so their recommended torque spec is about 25% less.
Regardless, NGK states to use no anti-seize, so there's a dilemma there. Denso makes no recommendation as far as I know. I installed a set of plugs last night with anti-seize (Denso SKJ20DR-M11) and I did not care for the feel of the threads at all...in fact I thought it was a bit nervewracking. I much prefer the progressive, solid feel of clean and dry threads when torquing spark plugs.
The only dilemma is in our heads (maybe a pun?)
The 14 mm, tapered seat plug in aluminum head torque spec. in my Caravan FSM is 13 ft. lbs. with anti-seize. The back of my NGK box recommends 7 -14 ft. lbs. without anti seize. In my case, there is not the difference you exclaim above.
On their website, NGK DOES recommend anti seize for non plated (black, plain steel) plugs. This kind of shoots a hole in their defense of altering torque/plug breakage, electrical conductance, and heat transfer.
I am 2 hours away from installing new NGK's in my Caravan. Since you have swayed to the dark side in trying the anti seize, maybe I will do likewise and NOT use it! I have already gone out on a limb using NGK instead of the "Chrysler loved Champions"
FSM's rules are meant to be broken. When I was a young pup, I remember questioning my father in law (diesel mechanic) about using regular lithium bearing grease on my '82 Escort....Ford FSM recommends ONLY 3% moly grease. I, and the Escort survived, despite the tongue lashing from my FIL.
IF/when I use antiseize on plugs, it doesn't even fill the thread valleys....very tiny amount (none on the tapered seat).
Sorry, Mr. Critic. You can attempt to top my OCD, but you will fail.
The 14 mm, tapered seat plug in aluminum head torque spec. in my Caravan FSM is 13 ft. lbs. with anti-seize. The back of my NGK box recommends 7 -14 ft. lbs. without anti seize. In my case, there is not the difference you exclaim above.
On their website, NGK DOES recommend anti seize for non plated (black, plain steel) plugs. This kind of shoots a hole in their defense of altering torque/plug breakage, electrical conductance, and heat transfer.
I am 2 hours away from installing new NGK's in my Caravan. Since you have swayed to the dark side in trying the anti seize, maybe I will do likewise and NOT use it! I have already gone out on a limb using NGK instead of the "Chrysler loved Champions"
FSM's rules are meant to be broken. When I was a young pup, I remember questioning my father in law (diesel mechanic) about using regular lithium bearing grease on my '82 Escort....Ford FSM recommends ONLY 3% moly grease. I, and the Escort survived, despite the tongue lashing from my FIL.
IF/when I use antiseize on plugs, it doesn't even fill the thread valleys....very tiny amount (none on the tapered seat).
Sorry, Mr. Critic. You can attempt to top my OCD, but you will fail.
Someone did a test concerning AS, and posted it on BITOG.
Having the lube on threads warranted a bit less torque, but any lube on the FACINGS of a nut REALLY warranted less torque.
It depends on where you put the AS, to some extent.
Also, the amount.
Having the lube on threads warranted a bit less torque, but any lube on the FACINGS of a nut REALLY warranted less torque.
It depends on where you put the AS, to some extent.
Also, the amount.
^^^I agree. Most plugs already have a specific coating designed to prevent seizing, so in most cases AS is not necessary.
But a small amount correctly applied is unlikely to hurt much either!
But a small amount correctly applied is unlikely to hurt much either!
Quote:
My Caravan specifies Champion or NGK plugs. Both recommend not to use anti seize. Yet, my factory service manual DOES recommend to use anti seize. shrug
http://store.wagaero.com/product_info.php?products_id=14255
From Autolite..
Quote:
Spark Plug Installation
New plugs should be installed using a thin film coating of high temperature nickel anti-seize on the ground electrode shield. DO NOT coat the ground strap. (see illustration 4)
It seems the manufacturers cant agree on this either.
IMO if you don't live in the salt belt or a high corrosion environment then it's probably not necessary
In the salt belt some plugs get so stuck your lucky you don't pull the threads or break the plug off so its a good practice to use it and apply it properly.
If the plug came out easy and is dry then you probably don't need to bother but if it was difficult to remove or squealed and screeched coming out then use it.
My Caravan specifies Champion or NGK plugs. Both recommend not to use anti seize. Yet, my factory service manual DOES recommend to use anti seize. shrug
http://store.wagaero.com/product_info.php?products_id=14255
From Autolite..
Quote:
Spark Plug Installation
New plugs should be installed using a thin film coating of high temperature nickel anti-seize on the ground electrode shield. DO NOT coat the ground strap. (see illustration 4)
It seems the manufacturers cant agree on this either.
IMO if you don't live in the salt belt or a high corrosion environment then it's probably not necessary
In the salt belt some plugs get so stuck your lucky you don't pull the threads or break the plug off so its a good practice to use it and apply it properly.
If the plug came out easy and is dry then you probably don't need to bother but if it was difficult to remove or squealed and screeched coming out then use it.
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