[Aredubjay]

Ah, found it. Posted 6/17/00 on the Yahoo board.


Sorry for the long story but I'm trying to save y'all some frustration. Concerning lubricants and anti-seizing compounds being applied to sparkplug threads.... If you go to NGK's website, somewhere in the FAQ's you will find their statement as to why they don't recommend anything on the threads. I don't recall it well enough to repeat it. Subaru does not recommend it because we have attributed misfire codes in the 2.5l motors, and had misfires in the 3.3l motor due to high resistance at the spark plug threads.
I don't currently endorse it, but at one time I did. When I started in this business 22 years ago (can that be possible?? I'm not that old!!!)The old guys that I worked with used neverseize to slather their spark plugs. Especially when aluminum headed motors became popular. I of course followed suit. Having been taught that not coating a steel spark plug in an aluminum head would mean the end of the free world. I religiously followed this procedure until 1990 when I went to work for my first Subaru dealer. Everyone in the subie shop followed the same notion. Except 1 guy who swore by atf on the threads. Anyway, as the turbo loyales got older we started having problems getting the spark plugs out. But we didn't see the same problem on the 1.8l mpfi xt. Even though it uses the same heads. Same plugs. Less heat, no turbo. Then I noticed that all these plugs that we had slathered in never-seize or atf had a brown sticky residue on the threads of the plugs ( on the turbo's, not the n.a.'s). I suspected that the compounds were "coking up". And contacted NGK. Eventually a rep from NGK showed up, Looked at my enormous collection of Spark plugs, some sticky, some not. He shook is head. And said," Do you have any idea how much money we spend in research every year?" I told him that I did not. "We roll the threads and apply a coating, there is no further attention needed. Quit putting never-seize on and your troubles will be over." I was skeptical but tried it. Over the next few years I was the only one in the shop not using a coating, and I was the only one in the shop that was not repairing spark plug holes or replacing cylinder heads on cars that I had previously tuned. Then the svx came out. We had some misfire problems after the first plug changes, not common, but it would happen. Subaru tracked the problem down to never-seize in most cases. On a side note, about half the old timers in my shop still wont buy it and believe they need to slather those plugs. And they do a lot of thread repair because of it. You can lead a horse to water......
danny