I've seen loads of youtubers (mostly U.S.) greasing spark plugs with anti seize compound prior to install. NGK have an article that says not to do this, due to risk of damaging plugs as it's possible to over-torque when greased, potentially damaging plug. I've read that you don't need to grease plugs with a shiny thread. NGK say their shiny thread is a trivalent plating that acts against corrosion and also acts as a release agent.
I recently fitted spark plugs for first time and decided not to grease threads on my bosch FR78X'S (couldn't find any info about this from bosch, maybe just my poor searching though). I tightened plugs to 25Nm. They have a shiny metal thread. What's the thoughts here, was I right not to grease the threads?
Yes
Thanks Carolyn
Yeah I don't grease my spark plugs, if they are bad enough to get stuck in the head then they aren't being swapped out in the right intervals, they don't need to be massively torqued up as they have a sealing crush washer to seal the plug.
Cheers. Yeah - funny, most of the guys using the anti seize also said they didn't bother torquing, just "knew when it felt tight enough". Did wonder if maybe they'd used anti-seize after having a bad experience with a stuck plug, because they'd overtightened in the first place s:wink: :wink: s:wink: