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Spark Plug "Antisiez"??

Vans101

Well Known Member
Hey there,

I have Lightspeed Plasma III ignition systems that use automotive spark plugs so the installation needs and adapter to size down from the airplane sized plug to the automotive plugs.

I have been using the aluminum colored anti-sieze lubricant on my spark plug threads however I am not too happy with the results.

After running the engine for 30 hours or so it seems like the sparkplugs are all REALLY tight and super hard to get out and they make a horrible binding noise as they get unscrewed. Often times the spark plug and the adapter come out together so that is frustrating.

Has anyone else experienced this issue?

Got a better product to use?

WD-40?

Not use anything and just brush the threads?

THANKS for the advice!!!
 
NGK says to put them on dry.

https://ngksparkplugs.com/en/resources/5-things-you-should-know-about-spark-plugs

5 THINGS YOU SHOULD KNOW ABOUT SPARK PLUGS

1. Anti-seize

NGK spark plugs feature 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 lubrication or anti-seize.

Anti-seize can act as a lubricant, altering torque values up to 20 percent, increasing the risk of spark plug thread breakage and/or metal shell stretch. Thread breakage can sometimes involve removing the cylinder head for repair. Metal shell stretch changes the heat rating of the spark plug and can result in serious engine damage caused by pre-ignition. Do not use anti-seize or lubricant on NGK spark plugs. It is completely unnecessary and can be detrimental.

2. Corona stain

Corona stain is a light brown or tan discoloration on the outside of the ceramic insulator above the metal shell/hex. Corona stain is created by the high voltage traveling thru the plug that attracts the dirt or oil particles surrounding the exposed ceramic insulator between the wire/coil boot and spark plug metal shell. Corona stain is completely normal and should not be mistaken for exhaust gas blow-by or a broken seal inside the spark plug.

3. Gapping fine-wire spark plugs

While most NGK spark plugs are pre-gapped, there are occasions when the gap requires adjustment. Care must be taken to avoid bending or breaking off the fine-wire electrodes. NGK recommends a round wire-style or pin gauge gap tool to measure the gap. If the gap must be adjusted, use a tool that only moves the ground electrode and does not pry between or against the electrodes. NGK also recommends adjusting the gap no more than +/- 0.008” from the factory preset gap.

4. Torque

Torque is crucial in the ability of the plug to dissipate heat and perform properly. Always follow the manufacturer recommended torque specification. An under-torqued spark plug can lead to excessive vibration and improper heat dissipation, causing spark plug and/or engine damage. Over torquing may cause any of the following: thread damage/breakage, compromised internal seals leading to gas leakage, metal shell stretch leading to poor heat dissipation and pre-ignition.

5.“Copper spark plugs”

“Copper spark plugs” is a term often used to describe a standard material spark plug. However, this terminology is incorrect, as standard material plugs do not have electrodes made from copper. Copper is soft with a low melting point and cannot be used for electrodes, as they would wear very quickly. A standard material spark plug uses a nickel-alloy that may include a small copper core. The copper core has nothing to do with the electrical performance of the spark plug. A copper core is used to increase heat dissipation and durability by lowering the electrode temperatures. Nearly all NGK spark plugs, including precious metal iridium and platinum plugs, have a copper core to increase the electrode durability. Special nickel alloys, platinum, and iridium electrodes, along with copper cores are all used to enhance durability – durability meaning how long a spark plug will last before it needs to be replaced.
 
It's a good point Mickey. As usual, there can be conflicting information. This from the OP's Lightspeed manual:

• Install adaptors in cylinder head using the supplied copper washer. Torque to 35 - 45 ft-lbs using anti-seize compound.
• Install automotive style spark plugs with their washer. Torque to 20 ft-lbs using anti-seize compound.


Rotax specifies heat sink compound on plug threads.

The Whizzer scooter manual specified weasel grease.

(Ok, I made up the last one.)

Vans 101, what procedure are you using?
 
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I have been using nickel based anti-seize with good results. Engine oil alone didn't do anything for me, removing those plugs was not fun. Have thought about seeing how copper works though as that is the one recommended.
 
Antiseize aside . . .

After running the engine for 30 hours or so it seems like the sparkplugs are all REALLY tight and super hard to get out and they make a horrible binding noise as they get unscrewed. Often times the spark plug and the adapter come out together so that is frustrating.

Do you chase the plug thread bore at every removal?

I have been doing this for a few decades as the combustion pressures pulse in/out of the thread cavities and allow carbon to form in there. This builds until the plugs stick. The tool is a Lisle 20200 thread chaser. If it is an odd size filing some grooves in a removed plug will serve as a throwaway tool.

I do this w or w/o anti-seize. I concur on copper type for spark plugs.
 
It's a good point Mickey. As usual, there can be conflicting information. This from the OP's Lightspeed manual:

• Install adaptors in cylinder head using the supplied copper washer. Torque to 35 - 45 ft-lbs using anti-seize compound.
• Install automotive style spark plugs with their washer. Torque to 20 ft-lbs using anti-seize compound.


Rotax specifies heat sink compound on plug threads.

The Whizzer scooter manual specified weasel grease.

(Ok, I made up the last one.)

Vans 101, what procedure are you using?

True.... But NGK is not the recommended plug for LSI.
 
True.... But NGK is not the recommended plug for LSI.

Which plug does LSI recommend? Here's a Denso FAQ which does not recommend "grease", but does not address a specific "anti-seize":

https://www.denso-am.eu/news/20180315_f2_spark-plug-frequently-asked-questions

Should I apply grease to the spark plug thread?

If a thread lubricant such as grease is coated on the thread, tightening of the spark plug increases when applying the same torque; this can cause damage to the spark plug. Subsequently, vibrations may cause the plug to come loose. Because of this, DENSO recommends not using a thread lubricant.

Only in a few exceptional cases (such as with some LPG-powered forklifts) may a small amount of grease be required. In such cases, the spark plug will be supplied pre-lubricated.

I have no idea what the right thing to do is, just providing some data that I found when researching this question myself.

One complication is that when we use auto plugs we often have the 18mm-14mm adapter, and what might be right between the adapter and the head might not be right between the plug and the adapter.

Champion says "use a little bit":

http://www.championaerospace.com/assets/technical/90-4.pdf

90-4.png
 
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I change a lotta plugs on a lotta airplanes and I don't use anything on the threads. They spin right out clean as they were installed. Will never use antiseize again. Doesnt do anything but gum up the threads.
 
Graphite vs Copper

Just to add more confusion to the mix, anyone ever notice Champion and Tempest recommend/sell graphite based anti-seize.........AND........Lycoming says "DO NOT" (their emphasis, not mine) use graphite anti-seize, use copper based anti-seize (Lycoming Service Instruction 1042 AH).

WRT rocketbob's comment: sorry, going with the engine makers recommendation, and using one of these if I can't spin the plug in by hand.
https://www.aircraftspruce.com/catalog/topages/1201683.php
 
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I change a lotta plugs on a lotta airplanes and I don't use anything on the threads. They spin right out clean as they were installed. Will never use antiseize again. Doesnt do anything but gum up the threads.

same here, though only a few planes and a lot of cars. Unless you plan to chase the threads regularly, I wouldn't use it. Had a few occassions where there was a bit of carbon on the first thread or two, but definately not difficult to get out; just extra resistance.

Larry
 
ATS2612 from Spruce

So far no mention of ATS2612 graphite? Copper does get really viscous and feels like your pulling threads removing the plug. This graphite stuff is very thin and plugs do come out easily. Heat transfer should be better or equal to Copper Goo.

Any input from you engine experts ?
 
So far no mention of ATS2612 graphite? Copper does get really viscous and feels like your pulling threads removing the plug. This graphite stuff is very thin and plugs do come out easily. Heat transfer should be better or equal to Copper Goo.

Any input from you engine experts ?

question is will it still be really thin after being exposed to 350-400* for 100 hours. Any of it that is on threads exposed to the combustion chamber will see 1500*+ I like to consider myself well experienced with engines and I see no need for it. Don't think I have ever seen a sparkplug siezed in a head. Suspension is a different story. Certainly would consider rocket bob to be highly experienced and he doesn't use it. If you think it helps in some way, use it. If not, don't. Very few in the auto engine world use it, if that means anything to you and their sparkplug threads sees the same temps we do, at least the bottom half. Heat transfer without compounds is quite effective, so no need to improve that. At 20 ft lbs with well formed threads, steel has very good thermal transfer.

Larry
 
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I bet no antiseize would work fine.. it’s a steel plug in a stainless thread insert. Besides we should be removing plugs once a year or every 100 hours, right? In the auto world, the plugs stay in for years and years.. plus they are in bare aluminum.. it’s a different animal.

I have good luck wire wheeling the plugs clean and using a light wipe of the copper stuff. The plugs come out fine. I think the people who use the thin stuff with the “fingernail” brush and don’t wirewheel the threads every time can experience the build up that gets sticky..
 
Well, part of this discussion has gone a bit off the rails (from the original post), so I may as well drive it a bit further.

everyone gets to choose. I certainly hope you are not running LOP, as lycoming recommends against it.

Larry

Sure, one of the coolest things about experimental aviation is "everyone gets to choose." But with that comes the added task of understanding what is being chosen and why. None of us knows all of the reasons a manufacturer recommends certain technical information about their product. Presumably they have test data and field experience. Choosing something other than what a manufacturer recommends, or an industry standard, or a best practice doesn't change the physics of what is happening in the part assembly, in this case a spark plug thread joint.

Even with a mechanical background and time wrenching on bikes, cars and an airplane, I do not know why Lycoming says "Use a copper-based anti-seize compound or engine oil on spark plug threads starting two full threads from the electrode, but DO NOT use a graphite-based compound." Sure, it has been demonstrated that aircraft plugs can be installed dry and removed without thread galling. My best guess (and it is only a guess without calling Lycoming tech support for the answer) is that the copper anti-seize or engine oil may be doing something other than providing an anti-seize function. It may be used to provide a more consistent thread friction, in turn providing a more consistent bolt pre-load when torquing the plug into the head. (Spark plug torque....kind of an important thing.) As for the no graphite call, that's likely a corrosion avoidance issue since graphite and aluminum do not play well together.

So my answer to this particular "don't know what I don't know" problem is to stick with the Lycoming Service Instruction. I'd rather be flying than trying to chase this one down. Also, I'd rather go with whatever their testing/data/field experience says rather than a that looks about right approach. Not knocking anyone's experience on this, it is what it is. Just saying there may be more to the story. (And seriously, one tub of the copper based stuff will probably last me 10 airplane lifetimes, not just the one I have. :) )

As for running LOP, the answer is no. Carb'd engine. Have not had research this one. Yep, read the articles and understand the arguments for it and have looked at engine data from those running LOP....just never had to push this one any farther. And, I suspect Lycoming (for reasons known only to them) will NEVER explain their position, technically....but that's something for another thread.
 
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... Sure, one of the coolest things about experimental aviation is "everyone gets to choose." But with that comes the added task of understanding what is being chosen and why. None of us knows all of the reasons a manufacturer recommends certain technical information about their product. Presumably they have test data and field experience. Choosing something other than what a manufacturer recommends, or an industry standard, or a best practice doesn't change the physics of what is happening in the part assembly, in this case a spark plug thread joint.
...
Steve, I could not agree more, and strongly recommend the same.

As you know, the challenge comes when the various suppliers give inconsistent advice. In the case of electronic ignitions using auto plugs in an aviation application, we have Lycoming, the ignition supplier, and the spark plug supplier not fully aligned. The good news is that I have not heard of too many aircraft falling out of the sky using no anti-sieze, copper, nickel, motor oil, or graphite, so it does sound like a simple matter of personal experience.

One thing I have read is that if you use some lubricant on the threads, it changes (reduces) the required torque, so it's up to the person putting in the plug to do it right.
 
Regarding auto plug inserts

Some potentially useful observations:

Copper on the the BRONZE threads of the insert and the larger diameter encourage the insert to stay in the engine more often than not.

Graphite on the smaller diameter plug in the BRONZE insert come out easily when installed per Emag instructions
 
As it happens, just last week I spoke to a Lycoming contact regarding the no-graphite prohibition in SI 1042AH. Can't share details (management likes everything vetted via official channels), but I can say the rationale would not apply to the interface between an auto plug and a brass or bronze adapter.

That said, I use copper base on the auto plug, and have seen no reason to quit. I'm not the only fella who ignores the NGK advice to install bare. For example, Honda specifies anti-seize for quite a few of their automobiles.

BTW, my bottle of antiseize dates back to VW beetles and airhead BMWs. Check out this instruction from a 1972 VW manual:
 

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As you know, the challenge comes when the various suppliers give inconsistent advice.

Mickey,

True. I think we have all run into this somewhere in the EAB world. That was my point in my original “anyone ever notice the plug makers graphite vs. engine maker copper” recommendation difference. Scratched my head over that for a while until deciding the engine maker ($$$$$$$ product) had the inside track over the plug makers ($$ product).

Maybe should have also mentioned in my case, standard massive plugs in a Lycoming head. Have not had to figure out the whole threaded plug adapter/auto plug interface thing. Someday, maybe.
 
As it happens, just last week I spoke to a Lycoming contact regarding the no-graphite prohibition in SI 1042AH. Can't share details (management likes everything vetted via official channels), but I can say the rationale would not apply to the interface between an auto plug and a brass or bronze adapter.

That said, I use copper base on the auto plug, and have seen no reason to quit. I'm not the only fella who ignores the NGK advice to install bare. For example, Honda specifies anti-seize for quite a few of their automobiles.

BTW, my bottle of antiseize dates back to VW beetles and airhead BMWs. Check out this instruction from a 1972 VW manual:

Dan,

I’d be really interested in what Lycoming says, if they ever decide to make it public.

Also, cool info from the VW manual! Wasn’t in my version of the Hayes manual for my 74 superbeetle. I don’t recall anything about plug thread lube/anti-seize in there. But, back then I’m not sure I knew what any of that stuff was. :) Good times.
 
Hi All,

I have not been able to get back online to see the responses until now...work happens.

It does seem that people are often amazed at the depth of my ignorance.

I was using the aluminum anti-seize because it is pointed out in the Light Speed manual.

I think the strategy moving forward will be to brush off the caked on material from the spark plug threads and then just go without the "lube" and see how that goes.

As always...Thanks for the advice!!!
 
>All I see in the LSE manuals is to use an anti-seize, without a specific one being called out.

Before this thread I thought that there was only one...the aluminum type that gets everywhere.
 
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