View Full Version : Anti-seize on spark plugs?
vwhugger
01-21-2018, 09:05 PM
On another forum there was a discussion about whether or not to put anti-seize on the spark plug threads when replacing them.
I have 2 Yaris' and have replaced the plugs once on the 2012 and three times on the 2008 and have never put anything on the threads and have never had any problems (seizing or stripping the threads). I've used Iridium plugs of different manufacturers (can't remember the brands).
Most comments on the other forum was that most people do put something on the threads.
Anyone want to comment on this and share your experiences?
I might add, the plugs have always been changed at about 120k intervals and have never been removed in between those intervals.
alanwagen
01-21-2018, 09:22 PM
If you use NGK plugs, they say NO. They have plated the threads. http://www.ngksparkplugs.com/about-ngk/spark-plug-101/5-things-you-should-know-about-spark-plugs
bronsin
01-21-2018, 10:21 PM
In my experience if you leave the original plugs in for 120,000 miles when you go to take them out they will be stuck. So I use anti-seize to prevent that
tmontague
01-21-2018, 11:33 PM
Anti seize all the time. I plating or coating that companies use in my experience doesn't work well at all. At the end of the day the owner of the one who is sol if they seize not the company.
You don't need to use a lot just a little goes a long way
zoidberg444
01-22-2018, 12:38 AM
Mine has regular copper core Denso plugs. I change them every 20,000 miles. I never bother. Normally just put a tiny toot of WD40 down when I break them loose. Then wipe the residue away with a rag before i put the new ones in. I find a bit of carbon builds up on the threads and they are very... dry. But i don't bother with anti seize. Never had an issue.
alanwagen
01-22-2018, 06:18 AM
My experience is that NGK make excellent plugs and believe they know what they are talking about. Over-torquing could be a disaster as anti-seize changes the whole dynamic for torque specs.
komichal
01-22-2018, 08:35 AM
I respect the manufacturer recommendation. NGK says no anti-seize.
Never had a problem. But I can imagine someone may have different experience.
bronsin
01-22-2018, 10:05 AM
If you take the plugs out regularly say every 20,000 miles and reinstall them after gapping and checking them, you probably won’t have a problem. Of course the plugs will usually last 120,000 miles (usually) but if you want to change them at $40 a pop that’s your call. That’s for iridium plugs. But I would bet the two dollar plugs would also last 120,000 miles. No lead in gasoline and fuel injection will see to that.
My advice is take The originals out at 20,000 miles and anti-seize them lightly and reinstall and leave them there till you change them at 120 K. It’s true the anti-seize will change the torque value the plug sees if you use a torque wrench so I go by feel.:headbang:
89GLH
01-22-2018, 12:09 PM
My experience is that NGK make excellent plugs and believe they know what they are talking about. Over-torquing could be a disaster as anti-seize changes the whole dynamic for torque specs.I was told the same thing about anti-sieze on lugnuts, too. If you use air to put em on the anti-sieze acts like lube and can fire them on tighter than torque specs would specify. I hate fighting with mine, so I still use it. I only use air to get em off, I put them back on by hand and use a torque wrench. Shrug.
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bronsin
01-22-2018, 01:28 PM
I agree!
tmontague
01-22-2018, 01:37 PM
I was told the same thing about anti-sieze on lugnuts, too. If you use air to put em on the anti-sieze acts like lube and can fire them on tighter than torque specs would specify. I hate fighting with mine, so I still use it. I only use air to get em off, I put them back on by hand and use a torque wrench. Shrug.
Sent from my VS995 using Tapatalk
I really hope no one is using air tools to fire on spark plugs:eek:.
Yes anti seize changes torque specs. However, corrosion and various metal wear and tear does as well so technically unless you are torquing a new nut in a new bolt the torque will never be the same as what the factory recommends so it becomes a moot point that always gets thrown around. Try this with never antiseized lug nuts/bolts and you'll see what I mean. You hit the 76ft/lbs way too early then a brand new or anti seized set up.
I never actually use my torque wrench for plugs so I always lightly anti seize them and hand snug them down. I typically will pull iridium's after every summer season to check how they look
white89gt
01-22-2018, 03:45 PM
The reason NGK and Motorcraft (and probably other manufacturers) have recommended no anti-seize is that effects the torque values, as mentioned. Over-torquing is bad in aluminum heads.
esse10
01-23-2018, 12:16 PM
Using anti-sieze does not change the torque value. It might make the threads go a little farther in because of the lubrication. 10 foot pounds is still 10 foot pounds.
example; if you torque a nut to 10 foot pounds and it stops at 12 oclock on the scale, if you lube the threads and torque the exact same nut then it will stop at around 2 oclock on the scale, but it's still 10 foot pounds. :thumbsup:
It's minimal difference I've used a little anti-sieze since day one with no issues.
alanwagen
01-23-2018, 05:56 PM
Using anti-sieze does not change the torque value. It might make the threads go a little farther in because of the lubrication. 10 foot pounds is still 10 foot pounds.
example; if you torque a nut to 10 foot pounds and it stops at 12 oclock on the scale, if you lube the threads and torque the exact same nut then it will stop at around 2 oclock on the scale, but it's still 10 foot pounds. :thumbsup:
It's minimal difference I've used a little anti-sieze since day one with no issues.
NGK disagrees with you: Anti-seize compound can act as a lubricant altering torque values up to 20 percent, increasing the risk of spark plug thread breakage. You and I are not qualified to contest their claim.
malibuguy
01-23-2018, 06:10 PM
I anti-seize everything that has threads. Including spark plugs. Dont need much on them since tbey really do not see any outside elements. I do it on spark plugs more for not tearing up the threads
SirDigby
01-23-2018, 10:44 PM
Mine has regular copper core Denso plugs. I change them every 20,000 miles. I never bother.
i find this interesting that you do not have problems with pre-detonation. on my honda i tried to run silver plugs and had all kinds of issues. the computer controlled ignition has the dwell resistance programmed in for platinum/iridium, and silver/copper core have almost no resistance resulting in an early spark. idk
on the anti-seize: the main reason i believe they don't want you using anti-seize is that people slop it all over and it can short out the electrode and drip into the cylinder and cause other issues. it is usually conductive, and could cause electrical issues.
saying that, i have always used anti-seize on spark plugs. i put a tiny drop on the threads of a plug, then i take a second plug and spin it around the threads if the first plug spreading the anti-seize all over the threads of both plugs in a very thin layer. never had an issue. i have however had to remove a seized,broken, and stripped plugs from a head. i'll take the risk.
xdarkxfirex
01-27-2018, 09:38 AM
No need to use antiseize on most plugs. Some heads like ford Triton have short threads and spark plugs tend to strip easily but not these cars.
vwhugger
01-30-2018, 04:18 PM
OK, thanks for all the comments. I think I'll continue to not use anything on the plug threads and we'll see what happens.
bronsin
01-30-2018, 04:23 PM
OK but do not leave them in for 120k without removing them to clean, gap, etc. on a regular basis.
Billiam
01-30-2018, 09:31 PM
I've never used AS on any spark plug ever. And I've changed a few in my nearly 34 years of driving. Never an issue
robkay
09-18-2018, 04:31 PM
NGK disagrees with you: Anti-seize compound can act as a lubricant altering torque values up to 20 percent, increasing the risk of spark plug thread breakage. You and I are not qualified to contest their claim.
Exactly. The torque value is based on the friction between the mating threads. Apply a lubricant and you change that. I would not do it on spark plugs.
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