Spark Plugs - Time Bound Maintenanace Interval ?

[paulo57509]

I've owned my '87 Acura for over 16 years and I never noticed this until a few days ago.



Not that I'm stressing over it, but why would Honda specify spark plug replacement based on time (...or mileage, which ever occurs first)? The only reason I can think of is removal difficulties may arise after long periods of time have elapsed; seized threads, etc. I've always based plug replacement intervals on mileage.

 

[tomcat27]

the interval should be based on mileage. I would imagine they have the "time" reference in there to simplify the chart for the items that DO consider time as a component of wear; and to ensure that they see your car and your money on a regular basis.

I have many cars that do not accumulate many miles, and I certainly use "miles" as a basis for replacing spark plugs. in fact, I just removed 22 year old motorcraft spark plugs from my cougar, and they looked great!

 

[deoxy4]

Think you are right about the concern about seizing. In my Honda manual it says to remove and reinstall at 60K miles and replace at 120K (?) miles. I later read somewhere that Honda doesn't put anti-seize on their plugs.

My plugs were in for just over 50K miles but 13 years. I ended up soaking the plugs overnight with half a teaspoon of penetrating oil and was very careful in removing. They were difficult to remove. I put anti-seize on them when I reinstalled. I will remove and reinstall more frequently in the future.

 

[mclasser]

I changed the original NGK plugs in my Accord at 166K miles. I was worried about seizing so I squirted some PB Blaster into the tubes overnight. Plugs came out easy-peasy and looked great for their age.

My Infiniti still has the original NGK's as well. At 14 yrs and 110K, they're due according to the manual. The back plugs are a PITA to access on these engines so I'm putting it off. Gas mileage is fine and the car idle's good so I may just wait til I get a misfire.

 

[BigCahuna]

Put a dab of never seize on the threads, and they'll come out without a problem next time you go to change them.,,,

 

[Mr_Joe]

Originally Posted By: BigCahuna
Put a dab of never seize on the threads, and they'll come out without a problem next time you go to change them.,,,


Yeah, but with many modern vehicles, after the one change the vehicle gets traded off before the 3rd set of plugs. Somewhere just under 100k miles is about my interval. I usually just get new and use the anti-seize.

 

[deoxy4]

Here is a photo of factory installed plugs at 116K miles in a Honda. Plugs look great. Thread don't look like they had any anti-seize on them.

http://www.bobistheoilguy.com/forums/ubbthreads.php/ubb/showflat/Number/2809346/Searchpage/3/Main/186447/Words/plugs/Search/true/Re:_Honda_K24Z1_Spark_Plugs_@_#Post2809346

 

[Leo99]

Put it together with Never-Seize and take it apart with guaranteed ease.

 

[CT8]

The plug threads are treated from the factory.

 

[Tosh]

from NGK:

Tech Bulletin -
Anti-Seize Compounds on Spark Plug Threads
Topic
The use of anti-seize compounds on spark plug threads that have a metal shell plating (i.e. Zinc or Nickel plating).
Issue
Applying anti-seize to the threads of spark plugs that have a metal plating allows the installer to mistakenly over-tighten the spark plug in the cylinder head; This stretches and fatigues the threads of the spark plugs, causing a much higher probability that the plug will break during installation or in some cases upon removal.
Example of 10mm thread spark plug broken during installation due to the use of anti-seize leading to over-tightening. (Note that plug gasket has been completely compressed, anti-seize can be seen on threads, and the break is in the direction of tightening).
Solution
For spark plugs with special metal plating simply do not use anti-seize on initial
Installation; All NGK Spark Plugs are manufactured with a special trivalent Zinc-chromate shell plating that is designed to prevent both corrosion and seizure to the cylinder head; Thus eliminating the need for any thread compounds or lubricants.
Additional Information
NGK recommends only using spark plugs with metal plating on all aluminum head applications to prevent damage to the head and plug. Metal shell plating acts as a “lubricant” which breaks away from the main body of the spark plug during removal, preventing damage to the spark plug and or threads in the cylinder head.

Summary
NGK Spark Plugs (U.S.A.), Inc. – Aftermarket Division
46929 Magellan Drive - Wixom, Michigan 48393
All spark plugs that have a blackened or dull appearance on the metal body offer no protection against seizing or bonding to the cylinder head and so it is with these spark plugs that anti-seize would be required. A spark plug that has a shiny silver appearance on the metal body usually indicates that the plug is manufactured with metal shell plating and therefore will not require anti-seize.

 

[paulo57509]

Originally Posted By: Tosh
from NGK:

Tech Bulletin -
Anti-Seize Compounds on Spark Plug Threads
Topic
The use of anti-seize compounds on spark plug threads that have a metal shell plating (i.e. Zinc or Nickel plating).
....


Thanks. We know this already.

 

[Stewie]

I think back then, they did not have iridium spark plugs

 

[deoxy4]

Thanks! I will admit that I did not know not to use anti-seize on the threads of NGK plugs. I have in the past used anti-seize and reduced install torque to 75% of recommendation so as not to over torque.

 

[slacktide_bitog]

Originally Posted By: deoxy4
Thanks! I will admit that I did not know not to use anti-seize on the threads of NGK plugs. I have in the past used anti-seize and reduced install torque to 75% of recommendation so as not to over torque.


Denso also says no anti-seize.