Decision time - what anti seize for spark plugs in Aluminum Honda engine?

[JHZR2]

I’ve never understood being OK with using copper antiseize in an aluminum application.

Yet I see a lot of recommendations to use it on spark plugs.

Today I’m stuck in this situation. OE spark plugs came out crunchier than I’d like from our 100k odyssey 3.5L V6.

That’s kind of the range of what I saw. A rusty colored finish on the threads in a range of brown tones.

Even chasing threads and loosely putting in a new plug, it came out dirty.

So, I’m stuck in the impasse - NGK says no antiseize the threads are coated with zinc chromate. Honda FSM says to use some. Doesn’t say what kind.

What should I do?

And what kind of anti seize? I have marine grade, silver, copper, and nickel.

Industrial Metal Service shares this chart;

Ugh, what to do???

 

[The Lube Guy]

Clean the threads as well as you can. Use a little bit of anti seize towards the tip of the spark plug, make sure none gets on the washer, otherwise it will throw off the torque spec. As to what kind of anti seize to use, I will leave that up to you. Personally, I wouldn't use copper in an aluminum head.

 

[JHZR2]

Clean the threads as well as you can. Use a little bit of anti seize towards the tip of the spark plug, make sure none gets on the washer, otherwise it will throw off the torque spec. As to what kind of anti seize to use, I will leave that up to you. Personally, I wouldn't use copper in an aluminum head.

My gut says no too but I’ve seen a lot of folks say it’s better because of markedly better electrical conductivity (like 10x).

The Cu-Al conundrum has me stalled…

 

[burbguy82]

Is the torque spec lubed or not lubed?

I have wondered this myself in the past, and decided against using the stuff. The reason why is: when you put the stuff on, and screw it in, and later remove the plug, some antiseize, years later is crusted up on the threads, and unless you chase the threads, and vacuum out the holes, some of that crud has to get into the combustion chamber. Which I am sure is not good.

I suppose that Honda says to is to protect the head from dielectric corrosion, and NGK say not to because of the zinc on the threads.

In your situation, I would not. But if you do, copper seems to work better in the long run, this is a subjective observation.

 

[GMBoy]

Rule of thumb is shiny plug threads = no anti-sieze. NGK and most other plugs are coated and no anti seize is needed. Your Honda manual may be spec'ing anti seize due to the stock plug not being coated. Over the years I have used tiny amounts of anti seize on all plugs and it was VERY hard for me to change the practice but I finally gave in when I started changing NGK and others at the 100k mark that came out just fine and never had anti seize. So - I don't use it if the plugs are already coated. The cheaper plugs like a basic autolite copper or similar with black oxide style threads still get a dab of anti seize.

 

[The Lube Guy]

My gut says no too but I’ve seen a lot of folks say it’s better because of markedly better electrical conductivity (like 10x).

The Cu-Al conundrum has me stalled…

Copper conducts electricity better than Aluminum, however, in can withstand heat better.

This would be the correct anti seize paste to use for your applicaton: https://www.permatex.com/products/l...ubricants/permatex-anti-seize-lubricant-1-oz/

It's a heavy duty blend of aluminum, copper and graphite lubricants in a petroleum base, and it will not evaporate or harden in extreme temperatures.

 

[The Lube Guy]

The Cu-Al conundrum has me stalled…

My apologies, there is also this if you wish to avoid copper contamination: https://www.napaonline.com/en/p/PTX...L7Aqm8aAiPeEALw_wcB&gclsrc=aw.ds&gad_source=1

 

[Nukeman7]

I have been putting Nickel anti-seize paste on NGK plugs in Honda 4 and 6 cylinder engines since 1980 and contrary to what NGK states, I have NEVER experienced any detrimental effects.

The spark plugs have always come out normally and not rusted/corroded. I also believe the minute amount of lubrication that it provides doesn't alter the final torque value enough in this (or lug nut) applications to amount to a hill of beans. While this is all anecdotal evidence on my part, I have replaced over 300 NGK plugs without any issue at all. I use a fair amount of anti-seize on all the threads, but am careful to avoid the electrode areas.

 

[oldcodger]

I always put a small amount on plugs. I have seen too many plugs frozen in place and even broken off in the head when they were being removed.

 

[JHZR2]

My apologies, there is also this if you wish to avoid copper contamination: https://www.napaonline.com/en/p/PTX...L7Aqm8aAiPeEALw_wcB&gclsrc=aw.ds&gad_source=1

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View attachment 221190

I have all kinds. Silver, nickel, copper, marine non metallic. All in my stock.

Copper and aluminum don’t seem right to me from a galvanic perspective. But in reality I don’t know if it matters…

 

[JHZR2]

I always put a small amount on plugs. I have seen too many plugs frozen in place and even broken off in the head when they were being removed.

What kind??

 

[JHZR2]

I have been putting Nickel anti-seize paste on NGK plugs in Honda 4 and 6 cylinder engines since 1980 and contrary to what NGK states, I have NEVER experienced any detrimental effects.
View attachment 221198
The spark plugs have always come out normally and not rusted/corroded. I also believe the minute amount of lubrication that it provides doesn't alter the final torque value enough in this (or lug nut) applications to amount to a hill of beans. While this is all anecdotal evidence on my part, I have replaced over 300 NGK plugs without any issue at all. I use a fair amount of anti-seize on all the threads, but am careful to avoid the electrode areas.

I think I read someplace that Ni type may be the Honda product implied in the FSM.

The OE plugs come out golden but not dirty from antiseize. IMO.

That’s the worst one. The rest are more golden.

@Trav, what kind of antiseize do you run on plugs going into Al heads?

 

[twX]

Use a little bit of anti seize towards the tip of the spark plug, make sure none gets on the washer, otherwise it will throw off the torque spec.

Even just applying anti-seize to the threads will increase the force on the threads at a given torque. Sometimes there will be a recommended torque reduction published on the anti-seize spec sheet. Reducing torque to 20% below the spec is a good rule of thumb.

 

[3783-KC1]

Believe you can use motor oil in a very small quantity as an anti-seize.

 

[twX]

Believe you can use motor oil in a very small quantity as an anti-seize.

You can, but it lubricates so well that it requires a large torque reduction, around 40-50%, compared to 15-30% for anti-seize.

 

[Dave9]

If forced to choose, I'd go with nickel, but on any platinum or better plug already plated with nickel, I usually put 'em in dry, unless I had a bear of a time getting the old nickel plated plugs out which isn't often. If they won't budge, warming up the engine a bit usually helps. YMMV.

I highly doubt that electrical conductivity is going to matter, not when you have resistive plugs, resistive wires, and the torque on the plug is going to get you some (near enough) metal on metal contact.

 

[flanso]

Some 40 years ago, my neighbor, was a salesman for Dow Corning, a manufacturer of anti-seize products. He told me to use anti-seize with a base dissimilar to the metals to which it is being applied.

 

[paulo57509]

I've been using Champion 2612 anti-seize (graphite) for close to 3 decades without spark plug removal issues. One observation is that the 2612 carrier does tend to "bead" when applied to threads.

 

[JHZR2]

Well, this is what I’m going with.

First, I’m chasing the threads with some oil on a cut bolt.

Then I’m very sparingly adding nickel anti-seize on a fraction of the upper threads.

These plugs are notionally going to be in there for another 100k. I’d rather it be done right, but since there apparently is none, I hope this is good enough.

 

[Donald]

People could crack and then tighten the spark plugs at say 50K miles to make sure they will come easily at 100K miles.