Rust/corrosion on spark plug threads

[Mosey]

Hi everyone. I just finished changing the spark plugs on my 2021 PB with 59560 miles. The plugs took a bit of force to break free due to rust/corrosion on the threads (see photos). The new ones threaded right in and were torqued to 18 ft/lbs. I did not use anti-seize.

I paid attention to the clocking of each plug and they all installed with the gap at approx 90 degrees from the intake. I was expecting better than that, but it is acceptable but I would have been happier if they faced directly at the intake. They are in the same relative clock position as the old ones.

Old plugs in the correct order with #1 lower left. Note the “rust” on the threads.

All the plugs showed about the same color. I measured the gap at 30 thou. The new plugs measured at 28 thou.

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[Dizz]

I’m a big believer in anti-seize it actually comes in an aluminum or copper formula
Have you heard it’s a bad idea?
I also have not heard of adjusting where they end up it must be a new thing

 

[Mosey]

I’m a big believer in anti-seize it actually comes in an aluminum or copper formula
Have you heard it’s a bad idea?
I also have not heard of adjusting where they end up it must be a new thing

Starting mid 2021 Ford went to indexed plugs.

 

[RcFlyer330]

I’m a big believer in anti-seize it actually comes in an aluminum or copper formula
Have you heard it’s a bad idea?
I also have not heard of adjusting where they end up it must be a new thing

With copper antiseize never use it on aluminum heads. Most spark plug manufactures recommend not to use anything on the threads. The only time i have used aluminum/nickle antiseize on spark plugs is in a seadoo where brp/rotax recommends it. The threads on the plugs above do not look rusted or corroded to me it just looks like normal used spark plugs. My best guess is the discoloration is carbon from buring gasoline. The carbon is tracking up the threads and being stopped by the copper sealing washer. This is why they are hard to remove the carbon acts like a thread locker.

 

[Dizz]

Well that makes sense
I always use the silver AS in everything from the lawnmower to everything
One important thing I see all the YouTube mechanics miss
When you crack a spark plug loose you always end up with some flaky rust around the base of the plug
I always hit it with the air hose
Then remove plug
The ASeize slows this down
Just remove a plug and shine a light and look
I had a groove in cylinder on a Civic I rebuilt and saw it and it always had lower compression
Just takes a second
I’ve learned a couple things here about the new type of plugs and I guess my 22 with the 2.7 has these plugs
I’ll have to see how they can be rotated
Thanks

 

[Dizz]

Another thing about the copper reactive to aluminum
I put a new transom wood core in my boat
Years ago treated wood used arsenic in some minute amounts to treat the wood along with other chemicals
It was outlawed at some point and guess what they use now?
Copper so I was unable to use it because it would destroy the aluminum
Marine plywood if you can find it is super $$$
I went another route
Crazy

 

[Mosey]

Well that makes sense
I always use the silver AS in everything from the lawnmower to everything
One important thing I see all the YouTube mechanics miss
When you crack a spark plug loose you always end up with some flaky rust around the base of the plug
I always hit it with the air hose
Then remove plug
The ASeize slows this down
Just remove a plug and shine a light and look
I had a groove in cylinder on a Civic I rebuilt and saw it and it always had lower compression
Just takes a second
I’ve learned a couple things here about the new type of plugs and I guess my 22 with the 2.7 has these plugs
I’ll have to see how they can be rotated
Thanks

Another thing I discovered. The copper washer is NOT a crush washer. When you torque the plugs to 18ft/lbs that is really as far as they will go in.

 

[FaaWrenchBndr]

Anti seize compound has not been recommended on spark plugs for about the last 25 years. The major brands have a coating on the threads that act as an anti-seize finish. It is also been stated that Nana sees can affect the spark plugs Performance due to heat transfer and electrical grounding or bonding.

Keep in mind it also changes the torque. It creates a what torque versus a dry torque. What torque calculations must be lowered approximately 22% to take account for the reduced friction of the threads.

So yeah, long story short bad idea for these engines

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