Spark Plugs

[freddie_ray]

What do you guys think about using anti-seize on the spark plug threads? I use just a lil dab from a stick when I change the plugs on my 12 FLHTK. I haven't had any problems yet.

freddie_ray

[Pirsch Fire Wagon]

Use it all the time.

[jls 64]

Use it all the time.

Me to.

[Hossamania]

Yep.

[JW113]

Many do. Even though spark plug manufacturers say DON'T. Silly spark plug manufacturers, what the hell do they know about spark plugs?



-JW

[smoserx1]

"A little dab 'ill do ya."  Remember that commercial?  Yea, I use it too, before antisieze I lightly oiled the  threads.  You sure don't want to be removing material from the head when you take them out.

[PoorUB]

I use anti-seize on spark plugs on every engine I own. It takes only one time to pull the threads, or have a seized spark plug before you realize it is a great idea.

I owned a Ford F150 with a 300. They were famous for the spark plugs to seize in the head. I have seen guys use a 1/2" breaker bar and a piece of pipe to remove spark plugs from a 300. A dab of anti-seize and they come out with a 3/3" ratchet and one hand.

[wildchild]

When using anti seize don't be heavy handed and put to much on, you only need a light smear on the first few threads as it will work around threads when the plugs are screwed in.

I use Permatex anti seize and tighten plugs to 12-18 ft-lbs (16.3-24.4 Nm).

Other options:
Loctite Anti-Seize 37617 also in a Silver Grade.
Typical Applications: For easy removal of spark
plugs, cylinder head and exhaust head bolts.

Loctite Anti-Seize 37616 in a Copper Grade.
Typical Applications: Spark plug threads installed
in aluminum, exhaust manifold bolts, engine bolts,
thermostat housing bolts, oxygen sensors, battery
cable connections.

[guido4198]

I was unaware that plug manufacturers advise against it. Does anyone know what their rationale is for that..??
For myself...I never go without it. I'm using Permatex Silver since the 1970's. No issues. When I install a plug, after applying the little dab to the threads...I sort of smear it into the threads just a little, then screw the plug in, and back out (just by hand...no tools..) to get the anti-seize uniformly distributed on the threads before screwing it back in and torquing it down.

[Skin]

I always dab a spot of Copper anti seize on spark plug threads on every service. New plugs, re- gapped plugs. its good for the job.

[smoserx1]

I was unaware that plug manufacturers advise against it. Does anyone know what their rationale is for that..??

I was also unaware of that but I can think of a couple of reasons they might say that.  One being too much antisieze being used could potentially cause the excess to migrate to the electrode area during installation with subsequent fouling or residue cooking during operation.  The other would be heat transfer.  A spark plug cools itself to some extent by being screwed into the head with the shoulder taper (or crush washer) being in intimate contact with the metal of the head (at least I think I read this somewhere, may be total BS).  Anyway I could see if maybe excess antisieze could impede this function.  However, either scenario would be unlikely unless the installer used way too much.  Use just a little, I like the copper.  And anytime I have needed to remove the plugs to service something I don't put more back on when reinstalling them.  The original application seems to stay on the threads just fine.

[wood02]

I use copper anti seize on spark plugs.

[Hossamania]

I use silver because I bought a jar 25 years ago and I still have at least a 1/4 left of it. Turns out, it still gets everywhere when I just look at it, much less actually use it.

[calif phil]

Modern spark plugs have thread coatings to prevent galling, no need for anti seize. 

[Dan89flstc]

I was unaware that plug manufacturers advise against it. Does anyone know what their rationale is for that..??

The spark plug manufacturers rationale is that they coat the threads with a sacrificial coating, making anti seize unnecessary, sounds reasonable to me.

There is no requirement for anti seize on spark plug threads in the 2019 M8 service manual.

[Geezer_Glider]

Champion 2612 spark plug anti-seize, I believe it is Graphite based. Use this or any other like it, no problems.
R Meyer

[Boe Cole]

I was unaware that plug manufacturers advise against it. Does anyone know what their rationale is for that..??
For myself...I never go without it. I'm using Permatex Silver since the 1970's. No issues. When I install a plug, after applying the little dab to the threads...I sort of smear it into the threads just a little, then screw the plug in, and back out (just by hand...no tools..) to get the anti-seize uniformly distributed on the threads before screwing it back in and torquing it down.

I'm certainly not an engineer or spark plug expert but I was under the impression that rationale for not using antisieze caused the knock sensing to not operate as it should.  Could be an old wifes tale for all i know.  BTW - I always use a dab of antisieze when installing plugs - better safe than sorry......

[hattitude]

FWIW... From NGK website:

1. Anti-seize

NGK spark plugs feature what is known as trivalent plating. This silver- or chrome-colored finish on the threads is designed to provide corrosion resistance against moisture and chemicals. The coating also acts as a release agent during spark plug removal. NGK spark plugs are installed at the factory dry, without the use of anti-seize. NGK tech support has received a number of tech calls from installers who have over-tightened spark plugs because of the use of anti-seize. Anti-seize compound can act as a lubricant altering torque values up to 20 percent, increasing the risk of spark plug thread breakage.

I've read that most spark plug makers these days have a similar coating...

I still put a dab on my plugs, but just a little. If I use anti-seize, I "snug" them up, don't torque them at OEM specs due to the risk of overtightening..

[kd]

FWIW... From NGK website:

1. Anti-seize

NGK spark plugs feature what is known as trivalent plating. This silver- or chrome-colored finish on the threads is designed to provide corrosion resistance against moisture and chemicals. The coating also acts as a release agent during spark plug removal. NGK spark plugs are installed at the factory dry, without the use of anti-seize. NGK tech support has received a number of tech calls from installers who have over-tightened spark plugs because of the use of anti-seize. Anti-seize compound can act as a lubricant altering torque values up to 20 percent, increasing the risk of spark plug thread breakage.[/color]

[PoorUB]

Well, duh! Most people way over tighten spark plugs anyway.  I "choke up" on the ratchet and just snug. Never had one loosen.

[SixShooter14]

Well, duh! Most people way over tighten spark plugs anyway.  I "choke up" on the ratchet and just snug. Never had one loosen.

same with lug nuts. And I'm guilty of it too.

[plumberglen]

Is it better to remove plugs from a warm engine ? Or a cold engine ?

[SP33DY]

In an aluminum head you should remove and replace the spark plugs cold. If the plug gets harder to turn as you are backing it out, spray some penetrating oil on the threads and let it soak to loosen the carbon build up. Forcing it when it doesn't want to turn can ruin the threads in the head.

[ziggy24]

Champion 2612 spark plug anti-seize, I believe it is Graphite based. Use this or any other like it, no problems.
R Meyer

Read on..... [attach=0]

[Dan89flstc]

Let`s read on some more...

The 2019 Service Manual says threads to be clean and dry.

From a legitimate Factory Service Manual, 2019: